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Sensory processing differences are common in autistic individuals as well as people who experience symptoms similar to psychosis. Social anxiety is also reported to be common in autistic people and people who experience psychotic-like symptoms. In addition to this, other research has suggested that psychological distress is common in autistic people and in individuals who experience psychotic-like symptoms, which some research has suggested could be related to sensory processing. As a result, this current research aimed to explore sensory processing, autistic traits, and psychotic-like symptoms in the general population, to investigate how much they explain experiences of social anxiety and psychological distress. Furthermore, although there is some research that has explored social anxiety in autism, it is not known how common it is for autistic individuals to experience social anxiety and what additional impact this has on other aspects of mental health and daily functioning. The first part of this thesis aimed to review previous research on social anxiety in autistic adults to firstly assess how common it is, and to secondly explore the additional impact on mental health and functioning. A total of 19 studies were identified after a literature search and were included in the literature review. Five of these studies assessed how common social anxiety is in autism, finding an overall rate of 76%. Studies also found higher levels of depression and anxiety, and lower levels of well-being in autistic people who experience social anxiety. Some studies also suggested that alexithymia (difficulties in recognising emotions) and camouflaging (masking autistic traits) may increase the risk of social anxiety. There are several limitations in this part of the thesis which are described in detail below. Clinical implications and future research are also discussed in the main body of the thesis. The second part of this thesis aimed to explore sensory processing, autistic traits, and psychotic-like symptoms in the general population, to investigate how much they explain experiences of social anxiety and psychological distress. An online survey was created and shared among social media platforms and with some mental health and autistic charities. The survey included questions on demographics, autistic traits, psychotic-like experiences, sensory processing, social anxiety, and mental health. In total, 273 people completed the survey and were included in the analysis. The results found that, in the general population, autistic traits, psychotic-like symptoms and sensory processing are all important in explaining the experience of both social anxiety and psychological distress. In addition, autistic traits, sensory processing, and psychotic-like symptoms were all significantly related to each other. Furthermore, 52 people who took part reported a formal diagnosis of autism; these people scored significantly higher on all measures used in the study (autistic traits, sensory processing, psychotic-like experiences, social anxiety, and psychological distress). However, the results of the study should be interpreted with caution due to the limitations of the research. The implications of the findings and suggestions for future research can be found in more detail below.

The objective of this thesis is to explore the effect of phrase frequency, word frequency and phonetic complexity (and their interactions) on production fluency in both children and adults. We explore firstly whether the previous findings for independent effects of phrase frequency, word frequency and word complexity on phrase production hold when using phrases that are simultaneously manipulated for all three factors, and secondly how the effects of these properties interact. In particular we aim to explore whether children's phonological learning, like that of adults, involves phonological/motor chunking. This refers to the idea that frequent sequences are represented in phonological working memory as a single unit which can be accessed directly, rather than having to be formed on the fly during production. Therefore, words that are difficult to say when first encountered become easier to articulate due to practice. An interaction between phrase/word frequency and complexity, where complex items are produced more fluently when they are also more frequent, would indicate that phonological/motor chunking is taking place. We also test the secondary prediction that phrase and word frequency will affect (promote or suppress) each other's effect on accuracy. In chapter 3 and 4 we asked children to repeat phrases manipulated for phrase frequency, word frequency and complexity, while chapter 5 uses the same stimuli in adults. We found that, overall, children do use phonological/motor chunking, but only for phrases where they have robust conceptual and phonological knowledge. Furthermore, we found that this effect was driven solely by word frequency in our stimuli - there was no effect of phrase frequency on production in children. Using the same stimuli, we found that adults also showed evidence of phonological/motor chunking for words which were high in frequency, although we found evidence of competition between word frequency and phrase frequency effects that was not seen in the children. Finally, Chapter 6 reports on 2 experiments which use a training session to manipulate non-word sequences for phrase frequency and word frequency. Again, we found that word frequency drives phonological/motor chunking during production. The results from these experiments suggest that young children and adults do undergo phonological/motor chunking. However, importantly, this effect is driven by word frequency - the phrase frequency effects seen elsewhere in the literature must be attributed to other mechanisms (e.g. long term memory associations between the constituent lemmas contained in high frequency phrases).

Literature Review – A Systematic Review Examining the Relationship Between Domain-Specific Self-Discrepancies, Depression, and Anxiety. Higgins' (1987) self-discrepancy theory proposes that discrepancies between specific selfstates are predictive of distinct emotional difficulties. Specifically, this theory states that actual-ideal self-discrepancies are predictive of dejection-related emotions whereas actualought self-discrepancies are predictive of agitation-related emotions. This has been empirically explored in relation to general self-discrepancies, with inconsistent support observed for this theory. The current review proposed to examine the relationship with domain-specific self-discrepancies and two psychological difficulties, depression and anxiety, to establish whether these relationships demonstrated more consistent results for SDT. 21 studies were identified following a systematic search process and the results were synthesised using a narrative approach. Similar to previous findings, results provided inconsistent and partial support for self-discrepancy theory. However, potentially important implications for the theory, including the importance of specific domains and measures of affect, are discussed. Overall, this review provides a rationale for further research to potentially support the development of self-discrepancy theory and considers the implications domain-specific self-discrepancies may have for clinical practice. Service-Related Project - Clinician Perspectives on the Use of Videoconferencing in Clinical Work with People with Intellectual Disabilities: Barriers and Benefits. This study describes a service evaluation conducted within an NHS Trust to explore clinicians' perspectives on the clinical use of videoconferencing with people with intellectual disabilities (PWID) during the COVID-19 pandemic. The aim of this project was to explore clinician's views on the barriers and benefits to the use of telehealth modality for PWID, in order to inform service-level decision making regarding the need to continue providing face-to-face support to this client group during the pandemic. In total, 21 clinicians working with PWID completed an online survey about their use of videoconferencing. A thematic analysis was conducted and identified barriers to the use of videoconferencing consisting of three main themes: "practical issues with modality", "client-related factors", and "clinician-related factors". Identified benefits consisted of two main themes: "practicalities" and "positive client feedback". Based on these findings, recommendations were made to address the modifiable barriers and facilitate the use of videoconferencing within the trust. This project concluded that whilst modifications may support the use of videoconferencing with PWID, there does appear to be a clinical need to continue providing face-to-face assessment and intervention. Hence, it may be beneficial for the service to incorporate both videoconferencing and face-to-face support in its ongoing clinical work with PWID. Main Research Project – Exploring the Roles Human Values and Self-Discrepancies in Postnatal Depression in First-Time Mothers. Human values and self-discrepancies have been empirically associated with general depression, anxiety, and subjective wellbeing, though their relationship with postnatal depression has not been explored. Schwartz's (1992) theory of human values and Higgins' (1987) self-discrepancy were used as theoretical frameworks within the current study, which examined the relationships between higher-order value importance, subjective value fulfilment, self-discrepancies, and postnatal depression. First-time mothers who had given birth within the last six months and self-reported as experiencing low mood/postnatal depression (N=80) completed the study. Actual-ought self-discrepancies, but not actualideal self-discrepancies, predicted postnatal depression. Neither value importance nor subjective value fulfilment was found to significantly correlate with postnatal depression, though the potential role of conservation values is explored. Furthermore, the potential impact of societal narratives on maternal actual-ought self-discrepancies is discussed, alongside the theoretical and clinical implications of these findings.

Hydrocephalus is a disorder when an excessive amount of cerebrospinal fluid (CSF) accumulates inside the subarachnoid space, which can lead to an enlargement of the ventricular system of the brain and increase the pressure inside the head. Paediatric population, adults, and most elderly ones can be affected by hydrocephalus. This neurological condition can have an excellent diagnosis if treated. However, it also can be life threatening if not treated correctly. With the increasing roll-out of 'digital hospitals', electronic medical records, new data capture and analysis technologies, as well as a digitally enabled health consumer, the healthcare workforce is required to become digitally literate to manage the significant changes in the healthcare landscape. In this study, Machine learning techniques are employed for the long-term follow-up for hydrocephalus patients, for which a data set of 3,262 records of ICP signals of shunted patients from Alder Hey Hospital, was used. Six popular machine-learning based classifiers have been evaluated for the classification of monitoring shunted patients and produce the required risk assessments to follow up shunted patients within a supervised learning setting, which are Ensemble Bagged Tree, Ensemble Boosted Tree, Fine Tree, Quadratic SVM, Gaussian SVM and Cubic SVM. The classifier Ensemble Boosted Tree achieved the highest aggregate performance outcomes of accuracy 98.90, sensitivity 100, specificity 100 and precision of 100. The study concludes that using machine learning techniques represents an alternative procedure that could assist healthcare professionals, as well as the specialist nurse and junior doctor to improve the quality of care and follow-up with hydrocephalus disorder.

A recent upsurge in the study of time perception in autism spectrum disorders (ASD) has suggested that atypical temporal processing may contribute to both phenotypical and clinically-defining aspects of ASD. The work presented in this thesis aimed to evaluate if atypical temporal processing does impact behaviour in autism and in particular whether it relates to core features of ASD. In the first part, we sought to establish whether time perception was indeed atypical in autism using a psychophysical short durations comparison task, and found that whilst a number of participants performed the task typically, a high proportion of autistic adults experienced difficulties to perform the task above-chance. In the second part, we turned our attention to temporal aspects of speech and gesture coordination in naturalistic productions. Focusing on a first set of data, we provided a progressive characterisation of successive levels of temporal organisation in communication, finding that autistic and non autistic adults differ mainly in terms of the structure of speech and pauses on the one hand, and gesture and holds on the other hand. Specifically, autistic adults showed similar asynchrony between speech and gesture (absolute delay between an event in speech and an event in gesture), but increased coupling (dependency between the speech and gesture signals) and diminished mutual information (repetition of patterns in the different communication channels), compared to their typically developing counterparts. Importantly, we showed that distinct temporal aspects of communication relate to phenotypical aspects (quality of communication ratings) and clinical severity (scores on the ADOS). Using machine learning algorithms, we found mixed evidence that acoustic and kinematic features of communication can predict a diagnosis of autism with high accuracy. However, an identical analysis on a second set of data failed to replicate the group differences at any level of the temporal structure of speech and gesture. We conclude with some recommendations for the most promising directions to explore in future research.

Depression and obesity are highly comorbid disorders, which are both characterised by chronic, low-grade inflammation. Chronic inflammation increases the risk for adverse health outcomes in patients with depression and obesity, but it is unclear whether excess weight or depressive symptoms are the driving factor contributing to increased inflammation. Research shows that the atypical depression subtype is associated with weight gain and metabolic abnormalities, and it has been hypothesised that atypical depressive symptoms may increase inflammation and exacerbate comorbid depression and obesity. Further highlighting the bidirectional relationship between depression and obesity, studies of obese patients with depression undergoing bariatric surgery have found that the rapid weight loss induced by surgery is associated with a dramatic improvement in depressive symptoms. However, other studies of bariatric patients have suggested that a pre-operative depression diagnosis is a contraindication for successful weight loss after bariatric surgery. Given the putative role of inflammation in the vicious cycle between depression and obesity, it is possible that inflammation may influence weight loss and changes in depression symptoms following bariatric surgery. My PhD thesis investigated the role of inflammation in association with depression, excess weight, obesity and bariatric surgery in four separate stages. Inflammatory markers included high-sensitivity C-Reactive Protein (hsCRP) and cytokines, such as interleukin-6 (IL-6) and interleukin-2 (IL-2), measured in blood samples. Anti-inflammatory markers included cytokines interleukin-4 (IL-4) and interleukin-10 (IL-10) measured in blood samples, and the stress hormone cortisol measured in saliva samples. Firstly, I investigated hsCRP and cortisol levels in a cross-sectional study of overweight and normal weight individuals, with and without depression. Secondly, I investigated hsCRP levels, cytokines and cortisol levels in association with depression in bariatric surgery candidates prior to surgery. Thirdly, I investigated changes in weight loss, depressive symptoms and hsCRP levels in bariatric patients 6 months after surgery. Fourthly, I identified baseline predictors of clinical outcomes (weight loss and depression) after bariatric surgery, by combining pre-operative and post-operative data from bariatric patients. In the cross-sectional study of depression and excess weight, overweight patients with depression had significantly higher hsCRP levels compared with overweight controls (p=0.042), normal weight depressed patients (p<0.001) and normal weight controls (p<0.001). Overweight patients with depression were at a significantly increased risk of having clinically elevated hsCRP levels ≥3 mg/L (odds ratio: 2.44, p < 0.001), relative to all other groups (all p > 0.1). No differences in cortisol levels were observed among groups. In the study of bariatric candidates prior to surgery, candidates with depression had significantly higher hsCRP, IL-6, IL-6/IL-10 ratio, lower IL-4, abnormal IL-2 levels and lower cortisol levels compared with control bariatric candidates (all p < 0.05). Atypical depression symptoms were associated with lower cortisol levels (p=0.02), but were not associated with higher hsCRP, IL-6, IL-6/IL-10 ratio, or lower IL-4 levels (all p > 0.05). In the follow-up study of bariatric patients 6 months after surgery, 19 patients (65.5%) with depression at baseline no longer met the clinical criteria for depression at follow-up. There were no differences in rates of weight loss or hsCRP levels at follow-up between patients with a pre-operative diagnosis of depression and control patients (both p > 0.1). Patients with atypical depression showed a trend for the greatest improvement in depressive symptoms at follow-up, compared with non-atypical patients with depression (p=0.08). Longitudinal analyses of bariatric patients showed that higher hsCRP levels prior to surgery predicted attenuated weight loss 6 months after bariatric surgery (β = -0.3, p=0.006). However, higher inflammation and attenuated weight loss were not associated with depression outcomes after surgery. Rather, higher depression severity prior to surgery and childhood emotional abuse were found to predict higher depression severity 6 months after bariatric surgery (β = 0.81, p < 0.001 and β = 0.31, p=0.001, respectively). Interestingly, higher atypical symptoms prior to surgery predicted a greater improvement in depression symptoms after bariatric surgery (β = -0.36, p=0.008). In conclusion, my findings provided evidence that depression significantly contributes to higher levels of peripheral inflammation, beyond the effects of excess weight and obesity. Moreover, my results suggested that higher inflammation is one of the driving factors predicting attenuated weight loss following bariatric surgery, rather than depression. My findings also raised the possibility that atypical depression is not associated with increased inflammation, but bariatric patients with atypical depression may be most likely to experience the greatest psychological benefit after bariatric surgery. Further research is needed to confirm these findings and investigate whether anti-inflammatory treatments may help to improve clinical outcomes after bariatric surgery and break the vicious cycle between depression and obesity.

Background: Eating disorders are mental illnesses characterised by persistent disturbance of eating or eating-related behaviour. Incidence and prevalence of eating disorders peak during late adolescence and emerging adulthood (~16-25 years of age), yet there are indications that this age-group's treatment needs are not well met. Emerging adulthood is a life-stage associated with distinctive characteristics (e.g. identity, autonomy and brain development; proliferation of life-events and transitions) and "developmentally-informed care" (i.e. service models and treatments adapted to meet developmental needs) may improve care for this age-group. Aims: This thesis aimed to assess current approaches to developmentally-informed care for emerging adults with eating disorders, and to explore directions for continued innovation of such service models. Methods: The thesis adopted a mixed-method approach (i.e. utilised both quantitative and qualitative methods). Chapter 1 outlines i) the rationale for innovation in eating disorder services for emerging adults, and ii) the concept of care informed by the developmental theory of emerging adulthood. Chapter 2 comprises a systematic scoping review of existing knowledge of eating disorders during emerging adulthood (e.g. epidemiology, aetiology, treatment approaches). Chapters 3 and 4 report qualitative evaluations of First Episode Rapid Early Intervention for Eating Disorders (FREED), a developmentally-informed service model for emerging adults with eating disorders. Chapters 5 and 6 comprise investigations of the relationship between distinctive characteristics of emerging adulthood (i.e. identity development; life-events) and eating disorder symptoms. Chapter 7 is a discussion of the thesis' findings and their clinical implications, its strengths and limitations, and suggestions for future research. Results: Findings indicated that the concept of emerging adulthood has yet to be widely adopted in eating disorder research. Some tentative evidence of associations between emerging adulthood's unique characteristics (e.g. identity exploration) and eating disorders symptoms exists. There is a dearth of current approaches to developmentally informed care for emerging adults, such that just one existing service model - FREED - adapts care to the developmental needs of emerging adults with eating disorders (Chapter 2). Emerging adults experienced FREED treatment as helpful and believed that FREED's focus on their developmental needs (e.g. managing life-transitions; balancing inclusion of family/friends with self-sufficiency) had been integral to psychological and behavioural changes (Chapter 3). Delayed help-seeking remains an issue in the FREED model, and development-related influences (e.g. life-events; preference for selfsufficiency) on help-seeking were evident amongst emerging adults (Chapter 4). Scarce high-quality research has explored relationships between identity development and eating disorder symptoms, but there is some low-quality evidence of bidirectional relationships between these variables (Chapter 5). Negative life-events were not associated with eating disorder recovery amongst emerging adults (Chapter 6). There was some preliminary evidence that positive life-events may increase the likelihood of recovery. Conclusions: Developmentally-informed care for emerging adults with eating disorders is in its infancy. However, one such service model (FREED) has produced promising results. Support with life-transitions, identity-focused work and the sensitive inclusion of family or friends in treatment may be particularly impactful developmental adaptations. There is a clear need for more high-quality research to further guide developmental adaptations to standard evidence-based services and treatments for eating disorders.

Depression and autoimmune diseases are frequently comorbid, and longitudinal studies indicate a bi-directional relationship. The mechanisms driving the bi-directionality are poorly understood, but shared genetic factors may contribute. The aim of this thesis was to investigate pleiotropy, the sharing of risk alleles, between depression and autoimmune diseases. Using data from the Psychiatric Genomics Consortium (PGC) and the UK Biobank (UKB), we identified affected individuals and applied a range of statistical genetics techniques to test for shared genetic influences. First, we investigated genetic variation within the Major Histocompatibility Complex, a region robustly associated with autoimmune diseases. We imputed Human Leukocyte Antigen (HLA) alleles, and Complement Component 4 (C4) haplotypes and tested the imputed variants for association with depression in affected individuals from the PGC and UKB. We found no strong evidence for association, indicating that any HLA or C4 variants associated with depression either are rare or have very modest effect sizes. With the objective of increasing the sample size for our subsequent studies, we next developed a genetically-informed framework for identifying individuals affected by depression in the UKB. We calculated the number of depression measures endorsed, including hospital episode statistics, interview data, and the gold-standard Composite International Diagnostic Interview (CIDI) completed by a third of participants. SNP-based heritability and variance explained by depression polygenic risk scores (PRS) increased with degree of endorsement. The genetic contribution to cases defined by at least two non-CIDI measures of depression approximated that for CIDI-defined cases. We conclude that multiple endorsements can serve as a reliable approximation where the CIDI is not available, and that our framework can be extended to identify other complex traits with increasing validity. Adopting our genetically informed framework, we next identified individuals affected by any of fourteen autoimmune diseases or depression in the UKB. We confirmed that depression was more common in autoimmune diseases, and vice-versa. Cross-trait PRS analyses were performed to test for pleiotropy, i.e. we tested whether PRS for depression could predict autoimmune disease status, and vice-versa. There was some evidence for association, but analyses showed weak effects, indicating that shared genetic factors do not play a major role in the observed comorbidity. Finally, we extended the project scope to apply PRS in an industrial setting. Using clinical trial data, we tested whether PRS for schizophrenia and correlated psychiatric traits were associated with treatment response to a novel compound developed for treatment-resistant schizophrenia. There was evidence for an association between treatment response and PRS for schizophrenia and bipolar disorder in the discovery sample, although the results were not replicated. Continued collaboration and data sharing will be required to achieve the sample sizes required to elucidate the common genetic basis of pharmaceutical treatment response. This work has demonstrated how the scale and breadth of large-scale biobank resources can be used to optimise the sample size and validity of complex traits, including depression and autoimmune diseases. Our findings indicate that shared genetic factors are not a primary driver of the bi-directional relationship, and future research should focus on identifying alternative risk factors involved in comorbid depression and autoimmune diseases.

Aim: To ascertain the association between antidepressant and suicidal ideation, self-harm, suicide attempt or death by suicide (ideation and death by suicide) and self-harm) within a secondary psychiatric healthcare setting. Methods: A mental healthcare database with appended text-mined data was used for analyses (including validation exercises and an exploratory study). A retrospective cohort study was carried out, in patients who received a diagnosis of depression during their first referral to psychiatric care services, in a series of studies aimed at understanding factors influencing antidepressant use, factors associated with new instances of suicidal ideation, self-harm, suicide attempt or death by suicide, identifying common antidepressant treatments and assessing the role of antidepressants in future instances of recorded suicidal ideation, self-harm, suicide attempt or death by suicide. Main analysis: Sensitivity and specificity tests were conducted to evaluate text-mining applications. Logistic regression analyses were conducted to determine factors associated with antidepressant treatment and suicidal ideation, self-harm, suicide attempt or death by suicide. Cox regression analyses were conducted to longitudinally assess associations between antidepressants with future recorded suicidal ideation, self-harm, suicide attempt or death by suicide. Results: For the text-mining applications, I found a precision of 91.7% and 82.8% for identifying suicide ideation and suicide attempt, respectively. The study ascertaining factors associated with antidepressant treatment found indications of comorbidity were associated with newer antidepressant use (e.g. SNRIs or mirtazapine). Different depressive symptom clusters were associated differently with antidepressant treatment use, suggesting clinicianpatient communication. In addition, in patients older than 25 years, past suicide attempts were associated with increased use of fluoxetine relative to sertraline. The prevalence of new suicidal ideation, self-harm and deaths by suicide were observed in 8.76%, 1.67% and 0.24% of the cohort, respectively. All three clusters of depressive symptoms - affective, somatic and cognitive - were associated with increased risk of suicidal ideation, self-harm, suicide attempt or death by suicide, compared to their patients who did not experience these symptoms. In terms of the longitudinal association of specific antidepressant treatment with suicidal ideation, self-harm, suicide attempt or death by suicide, results were found to be in line with current literature but also novel: i) There was no association of most of the specified antidepressants with suicidal ideation, self-harm, suicide attempt or death by suicide in young or older adults; ii) however, results suggest that compared to citalopram, mirtazapine and sertraline may be associated with increased risk of suicidal ideation in young people (HR 5.99; 95% CI 1.30 - 27.70; p-value 0.021 and 4.66; 1.52 - 14.24; 0.007, respectively), who experience cognitive symptoms (i.e. helplessness, worthlessness and hopelessness) during antidepressant treatment, iii) whereas mirtazapine (0.46; 0.22 - 0.95; 0.04) or dual combinations of antidepressant treatment (0.40; 0.18 - 0.90; 0.025) is protectively associated with ideation in adults, who experience cognitive symptoms, iv) contrastingly compared to citalopram, mirtazapine may increase the risk of self-harm in adults (23.7; 1.42 - 394.8; 0.02) who experience cognitive symptoms while and v) collectively, the results suggest a general role for mirtazapine increasing the risk of ideation compared to citalopram in adults, in the presence of certain symptoms. Hence, no direct evidence was found between antidepressants and suicidal ideation, self-harm, suicide attempt or death by suicide however there may be an indirect role via depressive symptoms. Conclusions: The current study is one of the first studies to use a naturalistic clinical psychiatric database in research studying the potential role of antidepressants in treatmentemergent suicidal ideation, self-harm, suicide attempt or death by suicide (suicidal ideation, self-harm and death by suicide) (See Chapter 2 and 7). The study calls for attention on patient symptom profiles over the course of mirtazapine treatment in secondary mental healthcare (Chapter 8). The limitations faced in this study (Chapter 5 and 6) requires all conclusions to be interpreted with caution and primarily calls for further studies to validate the current findings in particular dictated by substantial qualitative work given the inconsistencies in clinical text (Chapter 9).

A small group of men are responsible for most violent crimes, resulting in considerable interpersonal and societal costs. They meet diagnostic criteria for Conduct Disorder (CD) in childhood and Antisocial Personality Disorder (ASPD) in adulthood. Approximately one-third meet criteria for an additional diagnosis of psychopathy (ASPD+P), exhibiting callous unemotional (CU) traits from early in life, engaging in a broader range of offending behaviours, and responding less well to treatments than those without psychopathy (ASPD-P). Those with ASPD+P show particular deficits in empathic processing, while both ASPD+P and ASPD-P share deficits in decision-making. Evidence demonstrates that these clinical and neurocognitive differences may be explained by some shared, but some differential neurobiological underpinnings. However, the neurochemical underpinnings remain relatively under-researched. One neurochemical of particular interest is oxytocin- a neuropeptide shown to modulate empathic processing and decision-making in healthy populations. However, no study to date has examined its effect on neural processing of these functions in ASPD+/-P. The neurochemical underpinnings of shared decision-making deficits in ASPD+/-P also remain under-researched. One important consideration is regulation of striatal input into decision-making by Glutamate and GABA, which has not yet been examined in ASPD+/-P. In this thesis, I sought to address these gaps in the literature. Firstly, using a double-blinded, placebo controlled design, I explored similarities and differences in i) an important component of empathic processing (neural response to facial emotional expressions) and ii) decision-making in violent men with ASPD+/-P (n= 26 across studies), compared to healthy non-offenders (NO; n= 21 across studies), with placebo and after acute application of intranasal oxytocin, using functional Magnetic Resonance Imaging (fMRI). Secondly, I investigated differences in striatal excitatory/inhibitory (E/I) balance between groups, as measured by Glutamate:GABA ratio, using Magnetic Resonance Spectroscopy (MRS). Subjects were classified using Psychopathy Checklist PCL-R scores. In the first fMRI study, in the placebo condition, the ASPD+P group showed reduced responsivity to fearful faces in in bilateral cingulate cortex, compared to ASPD-P. Further, oxytocin abolished these differences and enhanced activity in ASPD+P, in these regions and also in bilateral insula. In the second fMRI study, there were no significant behavioural findings. While the task elicited an overall effect across the sample in bilateral cerebellum (offer phase) and anterior cingulate cortex (decision phase), there were no effects of group or oxytocin. In the MRS study, both ASPD+P and ASPD-P had lower Glutamate:GABA ratios than NO, though there was no significant difference between ASPD+P and ASPD-P. Glutamate:GABA ratio correlated significantly with a reward-based decision metric from a neuropsychological task ('Now or Later' task). Taken together, my findings provide further support for a model of some shared, but some differential neurocognitive deficits in ASPD+P and ASPD-P. They build on previous research supporting stratification of ASPD into subcategories of ASPD+P and ASPD-P. Importantly, for the first time, I have also demonstrated normalising effects of oxytocin in empathic processing in ASPD+P. This finding is a particularly important step forward towards developing targeted and effective interventions for this especially challenging patient population.

Gambling disorder (GD) is the most widely studied behavioural addiction (BA), however there is still an unmet need for more effective treatment strategies. With the aim to improve the understanding of transcranial direct current stimulation (tDCS) as a potential treatment intervention for GD, four experiments were conducted using different protocols and participant samples to measure neuromodulation effects during gambling-related task performance. In Experiments I and II, the effects of tDCS were investigated in low impulsive (LI) and high impulsive (HI) participants. Different high definition (HD) tDCS montages were used to target right dorsolateral prefrontal cortex (rDLPFC) and ventromedial prefrontal cortex (vmPFC), brain areas associated with decision-making and reward processing, respectively. Results revealed effects of tDCS on gambling task performance, but no difference on tDCS effects between rDLPFC and vmPFC targets, or between participant groups. In Experiment III, the potential cumulative effects of rDLPFC tDCS combined with cognitive behavioural therapy (CBT) were investigated across eight sessions, in two patients diagnosed with GD. The intervention combining tDCS and CBT resulted in reductions in gambling severity and cravings, but this effect was also seen in the sham tDCS case. In Experiment IV, physiological data, including electrodermal activity (EDA), electrocardiogram (ECG) and electroencephalogram (EEG), was used to investigate rDLPFC tDCS effects on the autonomous nervous system (ANS), in LI and HI gamblers. Results showed that real stimulation was associated with increased sympathetic activation compared with sham, which was higher during gambling-related wins compared with losses, and in HI compared with LI. There were significant correlations between gambling severity, cognitive outcomes and physiological variables, which helped to identify biological markers associated with GD. These results helped refine the knowledge of specific cognitive and physiological underpinnings of reward processing in different participant samples, and contributed to the development of novel treatment interventions for GD.

Psychologists, Counsellors and Psychotherapists have always had to manage risk of suicide. In the mental health context of the UK today the assessment and management of suicide risk holds an expectation that the psychotherapist will predict and prevent suicides. Working with someone that is suicidal evokes a myriad of responses in therapists and can impact them profoundly both professionally and personally in many different ways. This experience holds both the immediacy and urgency of facing a human being who feels unable to live, as well as the expectations in a wider context that they ought to be able to predict and prevent the suicides. This research study explored eight psychotherapists (three Counsellors, three Psychotherapists, and two Counselling Psychologists) experience of working with suicidal clients. Employing an Interpretative Phenomenological Analysis (IPA) methodology and utilising semi-structured interviews as the method of data collection. Analysing the transcripts according to the method recommended in IPA, three supraordinate themes (traditionally known as 'master themes') emerged: 'Emotional labour', which refers to how working with suicide risk impacts the participants; 'Navigating through the risk', which looks at how the participants understand and navigate the risk work; and 'What makes or breaks', which discusses the structures and processes that facilitate or impede this work for them. The themes are explored in relation to the existing literature on working with suicidality. The possible implications for clinical practice are discussed.

Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder that starts in early childhood and continues throughout the lifetime. The main symptoms of ADHD are inattention and hyperactivity/impulsivity. Even though substance misuse is one of the main comorbid conditions of ADHD, it has been an exclusion criterion in most studies of ADHD. The limited number of studies on ADHD and substance misuse measured ADHD as a whole, but in this thesis, the two main symptoms of ADHD have been divided to investigate the relationship between each symptom and developing alcohol, cannabis, and nicotine use. Studies show that individuals with ADHD and comorbid substance misuse become drug addicted at a younger age, use higher amounts of drugs, relapse is more common among them and ADHD medication treatments are less effective in them. There are common personality traits and impairments in individuals with the symptoms of ADHD and those who use alcohol, cannabis and nicotine. The studies of this thesis investigated the role of different facets of Executive Functions (EF), facets of impulsivity, emotional regulation, bipolar disorder and sleep quality in the relationship between each ADHD symptom and alcohol, cannabis, and nicotine use in typically developing participants. The results of Study 1 showed that hyperactivity/impulsivity explained additional variance after accounting for the facets of EF. Study 2 showed that inattention explained additional variance over and above the facets of impulsivity. Additionally, in studies 3, 4 and 5, emotional regulation, bipolar disorder and sleep quality were partial mediators between each ADHD symptom and some alcohol, cannabis and nicotine use scores, which are presented in detail in the next chapters.

Children and young people who experience domestic abuse, are at greater risk of a range of negative outcomes in adult life. Yet, all children and young people have the right to protection from violence and abuse, access to appropriate social, emotional and educational opportunities, and the right to access meaningful recoveries from harm. Despite this, there is a paucity of research exploring the mechanisms in place to support them. In Wales, an emphasis is placed on multiagency response to domestic abuse and there is growing interest in the role of schools in prevention and intervention for children and young people. A mixed-methods design was subsequently adopted, to explore professionals' views on the response to domestic abuse, with a grounding in the school system. Questionnaires were completed by 36 schools in Wales and a series of focus groups were held with children and young people's workers from specialist domestic abuse settings, school staff and social work staff. Data was analysed using descriptive statistics and thematic analysis; four overarching themes were developed. The findings illustrate, that whilst there are a variety of interventions and support available to children and young people, effective response is impacted on by the systems in place to respond to it. It is argued that current practice contributes to the maintenance of the issue, requiring radical consideration, if meaningful change is to take place for children, young people and their families. Implications for practice are discussed, including the role of the Educational Psychologist.

Speech and language therapists (SLTs) have a unique role in identifying and supporting children with autism spectrum disorders (ASD). Previous research outside the UK indicated that SLTs reported minimal training with this client group and knowledge of autism was lacking. In the light of adult learning theories identifying the key components of competence as knowledge, skills and experience, this research investigates how SLTs develop competence to work with children with ASD in the UK. This multi-phased mixed-methods research was designed in three sequential phases from different perspectives. Phase 1 consists of two parts: a comparative study of guidance of regulating bodies for pre-registration SLT training, and a search of autism content in training courses for SLTs across the UK. In Phase 2 semi-structured interviews were conducted with seven experienced specialist SLTs (experts) to investigate their views of how their own competence developed and how they support junior colleagues. Phase 3, utilising an online questionnaire including both open and closed questions, gathered the views of 119 newly qualified practitioners (NQPs) about their training. The results of the research showed that whilst awareness of the features of autism was generally reported to be included in pre-registration courses, the views of experts and NQPs were that training in the practical skills of assessment and treatment interventions was lacking and experience of working directly with children with ASD was limited, despite NQPs reporting that they were frequently required to work with this client group early on in their first posts and that they lacked confidence to do so. Recommendations are proposed to address the issues raised including revising the course content, improving the consistency and quality of continuing professional development through the use of a competency framework, thinking creatively about clinical placements, designing novel qualifications and developing an apprenticeship model of training.

This paper is made up of three distinct parts: Part 1 presents an introduction to the concept of autism, an introduction to the research around girls with autism and their diagnosis in adolescence, a focus upon the theoretical understandings of self-concept and social identity, and the way that these are viewed through a relativist ontology. Next there is a turn towards the use of discursive and social constructionist paradigms and a focus upon the prominent discourses around autism. Finally, this focusses into a review of the literature into the self-concept and social identity of autistic adolescents and culminates with a focus upon the area of enquiry and the research questions that emerged. Part 2 presents an empirical paper that sets out the research rationale, methodology and results for the study. Findings are discussed, followed by consideration of strengths and limitations, and implications for further research. Part 3 is a reflective and reflexive critical appraisal of the research process and the role of the researcher. It starts with a narrative account of the way the research subject was selected, and how the ontological and epistemological positionality of the researcher impacted the aims, orientation, methodology and data analysis undertaken in this work. It ends with a focus upon the contribution to knowledge and practice that this research makes.

Autism Spectrum Disorder is a lifelong neurodevelopmental condition associated with large lifetime costs to services, the individuals and their families. To develop appropriate support, a unified account of the condition needs to be found to provide a framework for research to build on. This thesis focuses on testing one of the recently proposed theories - the theory of High Inflexible Precision of Prediction Errors in Autism (HIPPEA), which interprets autism through a predictive coding perspective. The predictive coding framework argues that through experience, the brain forms predictions about the incoming sensory information, which it then compares with the actual input. Mismatches produce prediction errors which are weighed in comparison to the prediction, and if enough weight is assigned to the precision of the prediction error, a change in the prediction or the action is enacted. HIPPEA poses that autism arises from a difference in the tuning of this general neurocognitive mechanism whereby attention leads to the invariably high precision setting of prediction errors. This, in turn, leads to the creation of narrow prediction models that are based on infrequent contingencies and noise. This PhD aims to contribute research results and paradigm designs that investigate precision weight setting of prediction errors in autism. This thesis presents three behavioural and one neuroimaging experiments, and one meta-analysis. Each experiment modulates attention and expectation under different experimental paradigms allowing for the investigation of these two factors in multiple contexts. Chapter 2 makes use of an established apparent motion paradigm. In this chapter, endogenous attention is controlled allowing the investigation of the differences in prediction establishment and prediction error processing in neurotypical and autistic individuals. Moving forward, to establish the viability of using biological motion stimuli as an effective way to measure differences between autistic and non-autistic individuals, Chapter 3 presents a large-scale meta-analysis of behavioural, eye-tracking, EEG and fMRI studies investigating biological motion perception and interpretation in autism. Chapter 4 presents two studies that look at the effects of autistic traits in a task that orthogonally modulates attention and expectation by explicitly instructing participants about the statistical regularity of events and by providing implicit cuing using a human point-light kicker or a coherent dot-motion display. Finally, Chapter 5 presents a proof-of-concept study, which examines the feasibility of a modification in a recently developed EEG paradigm of hierarchical frequency tagging of bottom-up and top-down signals using dynamic human biological motion. This paradigm allows the investigation of the representation of low- and high-level components of the human point-light display, along with their integration in the brain while modulating attention and expectation through task instruction. The results from this thesis indicate that like neurotypical participants, autistic individuals can create and benefit from the development of predictions either through illusory motion or through the explicit establishment of expectations. In line with HIPPEA, this indicates that it is not the establishment of predictions that is the cause of the traits observed in autism. Moreover, what we see is that unpredictable events are treated differently, suggesting disproportionate amplification of unpredictable events, as suggested by HIPPEA. However, we do not see support for the 'inflexible' part of the HIPPEA theory. Instead, this thesis concludes that prediction errors show some special treatment in autism, but that is context-dependent. For research to move forward, it is paramount that attention is a controlled factor, and that context-dependent precision weight setting of prediction errors is incorporated in a reviewed version of the HIPPEA theory.

There is currently no evidence base for prescribing antidepressants or antipsychotics in young people with eating disorders. There is a need for greater understanding of psychotropic prescribing in individuals with anorexia nervosa (AN) to provide guidance for their use in clinical practice. The aim of this PhD was to explore and describe the drug utilisation and effectiveness of psychopharmacotherapy in individuals with AN. First, a systematic review was conducted to review the current literature. Next, pharmacotherapy in individuals with AN was explored by three means; 1) through self-reported questionnaires by child and adolescent eating disorder (CAED) psychiatrists on their prescribing practices in AN, 2) using The Health Improvement Network (THIN) database by reporting on AN patterns and describing prescribing patterns in AN in primary care, and 3) in multisite specialised child and young people eating disorder services (CYP EDS) within secondary healthcare settings by describing AN population and examining the effects of psychotropic treatment on weight change. Findings from my review fail to provide strong evidence for any increase in weight associated with the use of psychotropic drugs in adolescents with AN and show some evidence of harmful effects associated with their use. Studies in this thesis have shown there is a high use of psychotropics in AN treatment, with around half of individuals in the primary and secondary care study having a record for psychotropic prescriptions, of which olanzapine and fluoxetine are the most common. No serious adverse events were found in any of the studies. After six months of pharmacotherapy, the mean BMI of those individuals on antipsychotics was greater than the mean BMI of those on antidepressants or no medication, despite having a lower starting BMI upon diagnosis. This thesis found that although a lack of strong existing evidence, psychotropic medications are often prescribed for the treatment of young people with AN.

Huntington's disease (HD) is a genetic neurodegenerative disorder caused by a CAG repeat expansion in the huntingtin (HTT) gene that results in movement disorders and cognitive and psychiatric decline. To better track disease onset and progression, biomarkers that precede irreversible structural changes are needed. Alterations in metabolic processes detectable using magnetic resonance imaging (MRI) and other MR approaches may provide such biomarkers but need characterisation in HD mouse models to improve their clinical translatability. The aim of this thesis was to develop imaging biomarkers in transgenic R6/2 and knock-in zQ175 mice, two commonly used HD mouse models. To undertake the most comprehensive time-course analyses of metabolite concentrations in these models so far, proton magnetic resonance spectroscopy (1H-MRS) was acquired in selected brain regions throughout disease progression. Significant metabolic alterations were observed in zQ175 and R6/2 mice, with fluctuations at early disease stages. These changes suggested diminished neuronal integrity and reactive gliosis, which were confirmed using histology. Brain regions also exhibited specific metabolic profiles, many of said profiles being observed across both mouse models (albeit with some discrepancies). Chemical Exchange Saturation Transfer (CEST), which ought to overcome the limited sensitivity of 1H-MRS, was also acquired. However, we show CEST is not sensitive to HD pathology and do not recommend it for biomarker development in HD. Lastly, we acquired diffusion-weighted MRS (DW-MRS) in zQ175 mice to assess the diffusion of metabolites confined to cell-specific compartments. We found no changes in metabolite diffusion properties, but given the experimental nature of the protocol we used, DW-MRS needs further investigation in the context of HD. Overall, we have moved the field of HD forward by evaluating in detail the metabolic consequences of the disease in two mouse models that are widely used to investigate HD pathogenesis and evaluate therapeutic targets.

Research has shown evidence of the capacity for mentalizing being compromised in individuals with Borderline Personality Disorder (BPD) whilst there is evidence of the positive effects of treatments that focus on repairing the mentalizing capacity in this group of patients, such as Mentalization-Based Treatment. As emotional regulation in close personal relationships is an area that is particularly impacted in individuals with BPD, this paper aims at exploring the therapeutic process in Mentalization-Based Treatment Group paying particular attention to how mentalization may be generated through this process. This is achieved through a review of the existing theoretical and research literature around this topic. This review aims to provide further knowledge to therapists and clinicians in the area and also to identify possible gaps in the literature and possibilities for further empirical studies.

Epilepsy is one of the most common neurological disorders, estimated to affect 70 million people worldwide (Ngugi et al., 2010). Around 20 % of people with Idiopathic Generalised Epilepsy (IGE) continue to have seizures despite treatment with antiepileptic medication (Brodie et al., 2012). The mechanisms of epilepsy drug resistance remain poorly understood. Previous studies have primarily investigated potential cellular or genetic explanations for drug resistance. Epilepsy is regarded as a network disorder in which seizures arise via transient, abnormal, hypersynchronous activity of large-scale neuronal brain networks. An increasing body of literature demonstrates that people with epilepsy have different resting state networks than people without epilepsy. This thesis aims to investigate whether network alterations are also implicated in drug resistance. Resting state networks in people with well-controlled IGE, drug resistant IGE, and healthy controls were compared using spectral power analysis and graph theoretical analysis of data derived from EEG and fMRI. Converging evidence from the results demonstrated large-scale network alterations in people with IGE compared to controls. In particular, in IGE, there was a suggestion of greater cortical hyperexcitability and an alteration in the topology of the network, which had a more regular configuration. One of the studies also suggested that network topology in well-controlled IGE differed from controls, but not between controls and drug resistant IGE. We posit that this is due to a drug induced network alteration in people who respond to medication which stabilises the network, rendering it less susceptible to the seizure state. The cause of drug resistance in some people with IGE remains unknown, but may involve a complex interplay between multifarious brain networks, influenced by inherent epilepsy severity. The results of this thesis are of potential importance in furthering knowledge of how drug resistance arises and as a possible basis for an epilepsy biomarker.

The predictors of postoperative seizure freedom are not clearly defined in the literature. The proposed predictive variables, e.g., age at seizure onset, duration of epilepsy and gender, have not been uniformly agreed upon as useful prognostic tools and there is a need for a large-scale study to identify suitable predictors. An understanding of such predictors would be useful in counselling patients in the preoperative work-up, with a view to create an economically efficient healthcare service in which patients have optimal post-operative outcomes. Many scientific papers reduce postoperative outcomes to seizure freedom exclusively, with limited papers evaluating the impact of epilepsy surgery on depression and anxiety, which can also have profound impacts on quality of life. Epilepsy surgery grants researchers an opportunity to assess how brain functions are affected in the absence of particular cerebral structures. Knowledge of how brain function is affected by a lobectomy is important when consenting patients before surgery and informing them of possible post-operative deficits. One brain region in particular, the mesial temporal lobe, is of particular interest given it houses several structures that are alleged to help in memory formation and spatial cognition. However, there is contrasting evidence about the role of the mesial temporal lobe and the extent to which the mesial temporal lobe is involved in representing the environmental layout, the objects within in, as well as binding to the former to the latter (known as feature binding). In particular, it is not clear whether impairments of visual working memory are specifically spatial or rather generalize across visual feature dimensions (e.g., location, colour and shape) following focal temporal lobe lesions. This thesis attempts to address aforementioned gaps in the literature. Firstly, I provide a comprehensive literature review of epilepsy, including the role of epilepsy surgery in its management. Thereafter, I provide a systematic review of the literature exploring postoperative psychiatric and neuropsychological outcomes in patients who undergo epilepsy surgery in the absence of any pre-operative lesion/s on structural magnetic resonance imaging. Subsequently, I present original data showing the factors that predict post-operative seizure freedom in patients who have undergone resective surgery for epilepsy. The following chapter looks at the predictors of post-operative anxiety and depression in patients who have undergone resective epilepsy surgery. The penultimate chapter explores the factors that predict post-operative changes in working, visual and verbal memory in patients who have undergone resective epilepsy surgery. Finally, in a bench-side study conducted in Saudi Arabia, I studied a cohort of patients who had undergone temporal lobectomies for medically resistant temporal lobe epilepsy to establish whether impairments of visual working memory binding are specifically spatial or generalise across visual feature dimensions following focal mesial temporal lobe lesions. With regards to seizure freedom, I found that pre-operative generalised seizures are less likely to exhibit seizure-freedom than patients without pre-operative generalised seizures. I also found that patients with temporal lobectomies were more likely to exhibit seizure-freedom than patients with extra-temporal. Patients with a unilateral local focus on electroencephalogram and those with a lower frequency of pre-operative seizures were more likely to be seizure free at two years. With regards to anxiety, I showed that postoperative anxiety is improved if patients were female, underwent right-sided cerebral resections or had lateral temporal lobe resections. With regards to depression, patients with pre-operative generalized seizures were less likely to exhibit depression than patients with other seizure types. Patients with left-sided hemisphere laterality were more likely to manifest postoperative depression than patients with right-sided hemisphere laterality. Finally, pre-operative non-generalised seizures were associated with an improved post-operative verbal memory whilst no pre-operative factors were independently associated with improved visual or working memory. With regards to the bench-side study, we showed that mesial temporal lobe pathology is associated with binding impairments that are spatially specific. Our results were in keeping with the idea that the left rather than right mesial temporal lobe structures were specifically involved in spatial binding.

Autism Spectrum Disorders (ASD) and Attention Deficit Hyperactivity Disorder (ADHD) are co-occurring neurodevelopmental disorders emerging early in development. Molecular genetics research suggests that common sensory vulnerabilities underlie the emergence of both disorders, yet no research examined the same sensory markers as potential infant predictors of ASD or ADHD traits in toddlerhood. This thesis examines the early development of sensory perception in infants at elevated likelihood of ASD and/or ADHD and infants at typical likelihood of the disorders. Chapters 1-2 present, respectively, a theoretical introduction and methodological considerations for the investigation of sensory perception in these conditions. Chapter 3 presents evidence from an EEG tactile repetition suppression task administered to 10-month-old infants, prospectively re-assessed at 24 months. Results indicate that reduced repetition suppression is a marker of ASD in infancy and predicts ASD traits in toddlerhood. Results further suggest that early enhanced parent-reported tactile sensory seeking mitigates the association between tactile atypicality and later ASD traits. Chapter 4 presents evidence from an EEG visual task administered to 10-month-old infants, prospectively re-assessed at 24 months. Results indicate that enhanced responsiveness to visual input is a marker of ASD or ADHD in infancy and predicts concurrent parent-reported visual sensory seeking. Results further indicate that enhanced responsiveness to incoming stimulation in infants with later higher ASD traits results from reduced prioritization of ongoing information. Chapter 5 presents a proof-of-concept demonstration that variation in responsiveness to visual input also reflects variation in engagement with ongoing information in an independent cohort of 10-month-old infants at typical likelihood of the conditions. Chapter 6 adopts an individual differences approach and reports on the concurrent/longitudinal associations between markers of information prioritization emerged from Chapter 5 and parent-reported sensory seeking, ASD and ADHD traits in the same participant sample, prospectively re-assessed at 16 months. Chapter 7 discusses contributions and implications for research on the early development of sensory perception in ASD and ADHD.

Here we examined the sensory and motor consequences of Carpal Tunnel Syndrome (CTS), the most common nerve injury, caused by the entrapment of the median nerve at the wrist level. Patients experience impaired hand function, including diminished tactile sensitivity and impaired fine motor skills, and difficulty manipulating objects. The problematics reported by patients can partially be explained by tactile impairments. However, sensorimotor research underlines the importance of digit proprioception to perform 'smooth' and fluid hand movements. In Chapter 2, we assessed if CTS affects the anticipatory features of grasping movement towards real objects, with and without visual feedback. CTS patients showed preserved grip and speed scaling according to object size and distance, regardless of visual condition, slower movement in the absence of vision, and no increased movement variability. The results of Chapter 2 can be explained by impaired tactile sensitivity. However, as a consequence of the nerve entrapment caused by CTS, we assumed that digit proprioception is likely to be impaired. Therefore, in Chapter 3 we assessed if digit proprioception is impaired in CTS by asking patients and healthy controls to perform a haptic size-discrimination task to measure the sensitivity of opening of the unseen thumb and index finger. Contrary to our prediction, digit proprioception was not impaired in CTS patients. Considering the difficulties entitled in the assessment of digit proprioception and the lack of 'good' clinical tests, in Chapter 4 we developed a new tool to assess digit proprioception, the block-difference test. Overall, our results indicate that CTS preserves the anticipatory features of grasping movement and does not impair digit proprioception. Further, we underlined the importance of creating a better tool to assess digit proprioception and the challenges involved. The implication and limitation of these results are discussed with reference to both theoretical and clinical application.

Autism spectrum disorder (ASD) is a neuro-developmental disorder categorised by impairments in social communication and restrictions in behaviours and thought patterns. Applied behaviour analysis (ABA) is the applied branch of the science of behaviour analysis and is considered an evidence-based practice (EBP) for providing interventions for individuals diagnosed with ASD who are in need of support. In order to be suitably qualified to design and implement programs utilising the principles of ABA, an individual should be qualified as a Board Certified Behaviour Analyst (BCBA). When comparing the number of individuals with ASD who require support with the number of individuals qualified to BCBA level outside of the United States (US), the numbers of are scarce. This often results in individuals with ASD receiving interventions that are not considered an EBP. Secondly, those who deliver such interventions often have little training in the principles of behaviour analysis. Due to the high demand of individuals seeking a professional with a BCBA credential, BCBAs or those working towards the credential often experience a high rate of burn-out due to high service demands and the challenges that lack of effective supervision might pose. There is a huge need to investigate alternative delivery models that can facilitate BCBAs delivering services to those individuals with limited access to a qualified professional. One potential delivery platform is telehealth. Telehealth is the use of video conferencing software to connect individuals to a clinician within a wide range of health-related services. This thesis investigated the use of telehealth to provide behaviour analytic interventions effectively and efficiently and was done in three ways. Firstly, a systematic literature review was conducted to examine the current literature employing telehealth as a platform to deliver behaviour analytical interventions to individuals with ASD. Secondly, gaps highlighted within the systematic review were addressed in the main study. The main study utilised telehealth to train professionals in the principles of ABA and used live coaching telehealth sessions to assist in the acquisition of functional living skills in children with ASD. Finally, a follow-up study extending the current knowledge of conducting functional analysis (FA) and functional communication training (FCT) via telehealth was conducted. Each individual study within the thesis has contributed to the existing knowledge on the use of telehealth to provide behaviour analytic interventions to individuals with ASD. Recommendations for clinicians seeking to employ a telehealth platform and future research directions are discussed.

1) Systematic Review: A review of the usefulness and psychometric properties of the Parental Stressor Scale: Neonatal Intensive Care Unit (PSS: NICU) for measuring stress in parents of infants hospitalised in intensive care units across countries. The purpose of this study was to review publications which have examined the psychometric properties of the Parental Stressor Scale: Neonatal Intensive Care Unit (PSS:NICU), a self-report situation specific assessment for parents of hospitalised infants. The methodological quality of the psychometric measurement properties was assessed using the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) checklist. A narrative synthesis was conducted across studies to synthesise the psychometric properties examined, PSS:NICU scores, and descriptive data. 2) Empirical Study: Parents of Premature Infants: Exploring Experiences & Parent-Infant Relations. A Thematic Analysis. The purpose of this qualitative study was to explore primary caregivers' experiences of having an infant born prematurely (28-32 weeks gestation). In particular, the study aimed to explore the developing parent-infant relationship 12-30 months since birth and the developing parent identity whilst their infant was hospitalised and following discharge. Semi-structured interviews comprised open-ended questions and visual stimuli which consisted of photographs brought by participants and word selection techniques. Transcripts were analysed using Braun & Clarke's (2013) thematic analysis procedure and the data were managed using NVivo-12 software.

Psychopathic and sadistic patients share several common characteristics, such as emotional detachment from the suffering of the others and proneness to instrumental modes of aggression and crime. Despite voluminous literature the aetiology of psychopathy and sadism remain largely unknown, whereas psychological treatments for psychopaths and sadists are marked by therapeutic pessimism, as these patients appear intransigent to any therapeutic intervention. The aim of this thesis is to explore the early environmental antecedents that contribute to the development of psychopathy and sexual sadism and investigate how they are related to violent, sexually violent and sadistic behaviour. Further, the study examines the association between psychopathy and sexual sadism. This research followed a mixed-method design involving paper-based questionnaires, behavioural scales and semi-structured interviews. The results indicate that psychopathy is significantly associated with sexual sadism. The two constructs, however, follow distinct developmental pathways. Both psychopathy and sexual sadism were significantly correlated with early aversive experiences. The findings of the study showed that psychopathic and sadistic patients experienced more traumatic experiences, such as neglect, abuse and parental humiliation than the non-psychopathic and non-sadistic ones. Overall, the study findings indicate that these early traumatic experiences contribute to the development of psychopathy and sexual sadism and are specifically associated with severe forms of aggression.

Emotions play critical role in our lives. Communicating emotion is essential in building and maintaining relationships. Misunderstanding them or being unable to express them clearly may lead to problems in communication. People communicate their emotional state not just with the words they use, but also in how they say them. Changes in the rate of speech, energy and pitch all help to convey emotional states like 'angry', 'sad', and 'happy'. People with dysarthria, the most common speech disorder, have reduced articulatory and phonatory control. This can affect the intelligibility of their speech. However, producing less intelligible speech may not be the only problem affecting their communication; having dysarthria may make it hard to convey emotions in their speech in a way that can be perceived and understood clearly by listeners. Recent research shows some promise on automatically recognising the verbal part of dysarthric speech. However, we know very little about the ability of people with dysarthria to convey their emotional state through nonverbal cues. This thesis investigates the ability of people with dysarthria, caused by cerebral palsy and Parkinson's disease, to communicate emotions in their speech, and the feasibility to automatically recognise these emotions. Recognising emotions from speech is by itself a challenging problem. In the case of disordered speech, this may exacerbate the problem more as the speakers often have less control of the signifying features. A survey was designed and distributed to achieve a better understanding of different aspects related to emotion communication by people with dysarthria. A parallel multimodal, dysarthric and typical emotional speech database, which is a first of its kind, was collected and will be made publicly available. The ability of people with dysarthria to make systematic changes to their speech to convey their emotional state is investigated through analysing a set of potential acoustic features which are subsequently compared to those made by typical speakers. Their ability is also assessed perceptually and human listening performance on the collected database is reported. Two main approaches investigating the ability of automatically classifying emotions in dysarthric speech are followed: using models trained on dysarthric (speaker-dependent, matched) and typical (speaker-independent, unmatched) speech. The results of these investigations show it is possible to automatically recognise the emotional state of a speaker with dysarthria with a high degree of accuracy for some speakers. The work in this thesis shows that despite some speakers with dysarthria having a more limited articulatory and prosodic control, they can make systematic changes in their speech that help in the communication of their emotions. These changes are shown to be successfully perceived by human listeners as well as by automatic emotion recognition models. These findings demonstrate the potential for improved, more expressive voice input communication aids.

Depression is a leading cause of disability worldwide. Depression rates increase in adolescence with many new cases emerging at this juncture. Adolescent-onset, compared to adult-onset, depression is associated with more recurrences and an increased risk of chronicity. The long-lasting and severe outcomes associated with adolescent depression might be prevented through intervening earlier. Given gaps in evidence-based youth interventions and resource-stretched settings, innovations in this field are important. Cognitive mechanisms research suggests that dysfunctional mental imagery and overgeneral memory could be promising intervention targets for depression. The overarching aim of this project was to develop brief school-based psychological interventions to target these mechanisms in adolescents as well as pre-adolescent children (a time before the maximal age of incidence).

Symptoms of anxiety and depression are common and debilitating emotional problems, experienced by both adults and children. Described collectively as 'internalising' problems, they share much of the same genetic aetiology and typically co-occur in individuals. Robust evidence exists for the clustering of internalising problems in families, as symptoms in parents are associated with symptoms in offspring. Many questions remain as to the pathways underpinning such familial risk. Parent-offspring associations could reflect causal pathways, whereby parents' symptoms directly influence child symptoms, and vice versa. However, associations could be non-causal if the same genes influence symptoms in both parents and offspring. Understanding these processes can help to shed light on the pathways that shape our mental health and ultimately help to refine intervention targets to prevent the development of psychiatric problems. In this thesis I use genetically informative research designs to approximate and control for genetic effects in intergenerational associations involving parent and offspring internalising symptoms. Results help us to understand whether it is ever reasonable to draw causal inferences about the influence of parent and offspring internalising symptoms on one another. I present five studies to contribute both clinically relevant and methodological lessons. Specifically, I seek to explore the possibility of transactional effects or co-development between parent and offspring symptoms across time; seek ways to improve generalisability of findings by including data from a wider pool of participants; and attend to questions surrounding statistical power to detect genetic effects in families. In my first study I conduct a meta-analysis to show that concurrent associations between parent anxiety and offspring internalising problems withstand correction for genetic confounding, while associations involving prenatal exposure to maternal anxiety do not. In my second study I use data from a longitudinal adoption cohort to show prospective prediction from child anxiety symptoms to mother anxiety symptoms during middle childhood; and prospective prediction from father anxiety symptoms to child anxiety symptoms. In my third study I show that associations between parental criticism and adolescent internalising problems withstand correction for genetic confounding, using an extended Children-of-Twins design. I present power analyses for the detection of genetic confounding using this design and explore the possible direction of causation between generations. In my fourth study I introduce a novel approach to combining developmental methods with a statistically powerful Multiple-Children-of-Twins/Siblings model. I show that mothers' internalising symptoms do not co-develop with offspring temperament during early childhood, although baseline stability in mothers' symptoms is associated with baseline stability in offspring emotionality, via both genetic and non-genetic pathways. In the final chapter I discuss the findings and limitations of these approaches, alongside possible avenues for future research.

There is a sharp increase in depression in girls in mid-adolescence, but we do not understand why this occurs. Cognitive theories suggest that people with depression have more dysfunctional attitudes and negative biases in social information processing (perceiving, interpreting, and remembering their social environment). In my thesis, I tested the hypothesis that these negative cognitions contribute to the gender difference in depression during adolescence. I examined whether girls have more negative biases in social information processing and dysfunctional attitudes than boys, and whether biases are associated with depressive symptoms in early and mid-adolescence. I collected data from 331 young and 268 mid-adolescents (aged 11-13 and 13-15 years). In chapter 3, I tested whether learning about social evaluation differed across genders or age groups. I then developed and validated computational models of learning about social evaluation in chapter 4. In chapter 5, I tested whether recall biases were more negative in young and mid-adolescent girls and were associated with depressive symptoms. In these chapters, I found that negative biases in learning about social evaluation and recall were associated with increased depressive symptoms in young and mid-adolescents. There was no strong evidence for gender differences in social information processing. In chapter 6, I tested whether there were gender differences in different domains of dysfunctional attitudes. I found that perfectionism was associated with more severe depressive symptoms across adolescence and girls had higher perfectionism than boys in mid-adolescence. My findings suggest that social information processing is not more negatively biased in girls than boys during adolescence, although girls may have more perfectionism than boys. Negative biases in learning about social evaluation, recall of social evaluation, and perfectionism were associated with depressive symptoms from early adolescence. These negative biases may be a risk factor for depression and present a good candidate for future longitudinal studies.

When solving syllogisms, people can adopt either a spatial strategy, where spatial representations are used to illustrate relations between terms, or a verbal strategy where the problem is represented in terms of letters and relational rules (Ford, 1995). People with dyslexia tend to adopt a spatial strategy when solving syllogisms while people without dyslexia tend to adopt a verbal strategy (Bacon, Handley & McDonald, 2007). But how fixed are these strategic approaches? This thesis examines whether training that focuses on verbal or spatial representations of the problems affected performance for people with and without dyslexia, and whether the effectiveness of this training varied according to whether the syllogisms were categorised as those easiest to solve for verbal reasoners, easiest for spatial reasoners, and equally difficult for both types of reasoners, based on Ford's (1995) results. Five studies were conducted to compare the performance of people with dyslexia to people without dyslexia to examine 1) individual differences in spontaneous reasoning strategies, 2) effects of figure and belief bias, 3) performance after being taught a verbal strategy, 4) performance after being taught a spatial strategy, and 5) the pattern of eye movements to observe where attention is focused while solving the syllogisms. The results supported previous research that people do tend to reason spontaneously with a verbal or spatial strategy but failed to find evidence of a difference between participants with dyslexia and participants without dyslexia. The studies further showed that participants with dyslexia are affected by the figure of the syllogism (the placement of the middle term in relation to the end terms). Training was effective in encouraging all participants to switch solution strategies, but this appears independent of dyslexic status. Teaching a spatial strategy impacted learning but did not promote problem solving and was not particularly helpful for the participants with dyslexia. It appears to make problems that are easier with a verbal strategy harder to solve. Examination of eye movements revealed that the focus of attention during problem solving was more on the terms in the premises than the quantifiers. The pattern of eye fixations was the same regardless of the figure or problem type. There was an interaction between problem type x AOI, indicating a longer processing time for premise 2 for problems that are difficult to solve with a verbal or spatial strategy. Overall, the studies suggest that there is a burden on participants with dyslexia in problem solving that is not alleviated by training in either spatial or verbal strategies, but that particular problems might be easier or harder to solve according to whether a spatial or verbal strategy is spontaneously used by the participant, and that these differences in problem type are marked by eye fixation patterns during problem solving.

Public visibility of autistic people has increased significantly since the early 1990s. Diagnosis rates of autism have risen in Western countries, whilst cultural representations of autistic people have proliferated across various forms of media. This period has also seen the emergence of the neurodiversity movement which views autism in terms of difference rather than defects and politically organises to challenge disablist oppression. This thesis explores the ways in which autistic people have been represented as sexual and gendered subjects in the United Kingdom from the early 1990s to the present day and analyses the implications of such representations for autistic people's lives. It considers how influential representations of autistic people, for example, pop cultural portrayals of autistic people as male geeks, have been challenged by autistic self-advocates who argue that such framings fail to recognise autistic people's diverse experiences. Over the course of this thesis, I combine critical theoretical work from across the humanities and social sciences with empirical analysis of a selection of texts in order to develop a multifaceted account of how autistic people are represented as gendered and sexual subjects in the contemporary moment. I analyse a range of texts exploring autistic people's experiences of gender and sexuality, with my sample including self-help books, academic publications, television shows, and autistic self-advocacy writing. Drawing upon theoretical work from neurodiversity studies, disability studies, feminist theory, and queer theory I intervene in ongoing debates and controversies surrounding representations of autistic people as gendered and sexual subjects, for example, the moral panic over the public visibility of young autistic gender variant people. I demonstrate the complex ways in which framings of autistic experience produced within scientific research inform popular media texts, as pathologising, essentialist, and infantilising medical and psychological terms are troubled and reproduced by such texts. I show how texts produced by autistic people challenge biomedical and psychological framings, offering more inclusive representations which recognise autistic people's gender and sexual diversity. These texts highlight the role of social factors in shaping autistic people's lives and provide platforms for the perspectives of autistic women, gender variant people, and LGBTQ people. I argue that these works can inform future academic research within the social sciences and humanities, offering more sociological and critical accounts of autistic people's experiences, and can encourage alternative representations of autistic people in popular culture. Writing as an autistic scholar concerned with issues of disability, gender, and sexuality, the thesis synthesises existing theoretical and original empirical work in order to develop a sociological analysis of biomedical, psychological, and cultural representations which affect autistic people's lives. In this way, the thesis contributes to the growing field of neurodiversity scholarship within academic research.

There has been increased scrutiny of occupations who less obviously experience adverse impacts from indirect exposure to trauma. This thesis aimed to understand occupational distress in non-traditional professions, who might similarly experience secondary trauma through exposure to traumatogenic material; legal profession and law enforcement. Literature Review: A systematic literature review explored the prevalence and predictors of secondary trauma in legal professions. Repeated exposure to clients who have experienced trauma comprises a significant part of lawyers', attorneys', solicitors' and judges' roles. The search elicited ten articles for review. Quality appraisal showed significant methodological limitations in the studies. Still, results showed a high prevalence of secondary trauma, compared to population groups and other professional groups. Predictors included gender, work experience, personal trauma and level of exposure. Findings and conclusions are discussed and indicate that the significant variability between studies suggest a need for conceptually consistent and scientifically robust studies in the future. Research Report: The research report examined secondary trauma prevalence and predictors in English and Norwegian investigative interviewers, as well as the potential role of empathy in the development of secondary trauma. Police officers whose work task involved investigative interviewing were invited to complete an online survey, consisting of questionnaires measuring psychological distress, secondary trauma, empathy and perceived organisational support. The results indicated moderate levels of distress and secondary trauma, which were found to be higher than reported national and international norms. Secondary trauma was found to correlate with wider psychological morbidity, and predictive models of distress and resilience were suggested. Findings emphasised the need to implement organisational support structures and resilience-building schemes to sustain police officers in key roles to ait the vulnerable and secure prosecutions.

Interventions for Work-related Distress Among Paediatric Nurses: A Systematic Review. Objective: To critically appraise the empirical evidence regarding effectiveness of psychosocial interventions for the mitigation of work-related distress (WRD) among nurses working in paediatric settings. Methods A systematic search was performed across six bibliographic databases; a narrative framework for synthesis was employed. Results Seven studies were elicited for review: these evaluated interventions with diverse foci, utilising highly heterogenous measures to evaluate effectiveness. Whilst five of the studies reported statistically significant improvements on measures of WRD, and another a statistically significant increase on a WRD construct within one group of participants, the only RCT reported no significant effects of the intervention. Conclusions Given the infancy of research, heterogeneity and variable quality, specific recommendations are precluded from findings to date. Further research is required to build an evidence-based case to guide policy and resource allocation. Concordance of the SCQ and ADOS in Identifying Autism Symptomatology in Genetic Syndrome Groups. Objective: To assess the performance of an autism screening tool, the Social Communication Questionnaire (SCQ) in relation to the more "gold-standard" Autism Diagnostic Observation Schedule (ADOS) within genetic syndrome populations, in which social, communication and behavioural difficulties, and levels of intellectual disability, are also commonly present. Methods Using archival data, performance of the SCQ was examined in relation to ADOS classifications in genetic syndrome groups via ROC curve, sensitivity, and specificity analyses. Results At established cut-off the SCQ achieved a sensitivity value of 63.91% and specificity of 61.39%. Analyses by genetic syndrome group suggested uneven test performance, however confidence intervals were wide, with considerable overlap between groups. Conclusions Findings suggested the SCQ may perform less well for ASD associated with genetic syndromes than for idiopathic ASD. This may have implications, both clinical and theoretical, for identifying ASD in these groups.

The experiences of autistic females, particularly those of adult women are not well understood. The way that autism has been conceptualised traditionally has contributed to knowledge being largely extrapolated from experiences of autistic men and children. Lived experience research provides a valuable resource for understanding hard to reach voices, such as those of autistic women without intellectual disabilities. Existing research has examined the impact of "autism" on the person diagnosed with it, the impact of autistic people on others, and how culture may impact on how autism is understood. However, we have rarely questioned how culture has impacted on autistic people. This becomes more pertinent as the aetiology for sex differences in autism remain unclear, and we start to consider the role of gendered socialisation on how autistic women may present. This study aimed to examine how autistic women have made sense of their lived experiences in the context of the culture they are embedded within. This was achieved through an Interpretative Phenomenological Analysis with eight autistic women with no diagnosis of intellectual disabilities. Three core themes emerged highlighting the pervasive impact of socio-cultural values on participants, followed by how they have individualised as autistic women, and finally reflecting on the importance of staying connected with society for them. By understanding autistic women in their contexts, a more representative portrayal of their relationships with others, strengths and needs was also offered. These have implications for the continued need to shift attitudes in society through dissemination of knowledge; and clinical implications for cultivating identity development and the building of meaningful connections with society for autistic women.

Intrusive memories represent a hallmark symptom of post-traumatic stress disorder (PTSD). Cognitive theories of PTSD hypothesize that intrusive memories result from disruptions in information processing during traumatic memory encoding. The affective, cognitive, and behavioural reactions taking place during trauma have been termed peritraumatic reactions. These include reactions such as peritraumatic dissociation and tonic immobility. Experimental evidence has supported the theoretical claims concerning the role of peritraumatic reactions in the development of intrusive memories. This literature, however, presents a number of limitations. First, it relies on a conceptualisation of peritraumatic reactions based largely on quantitative measures with a large degree of conceptual overlap. Secondly, the identification of peritraumatic reactions has relied on clinical expertise, theory, and animal models, rather than on systematic investigations of survivors' lived experience. Finally, studies on peritraumatic reactions and intrusive memories, have generally assessed peritraumatic reactions for the entire trauma rather than for the specific moments experienced as intrusive memories. This thesis set out to address these limitations. Firstly, I investigated the factorial structure of the six most widely used peritraumatic measures. This led to the identification of a psychometrically validated model comprising five distinct peritraumatic reactions. Secondly, I explored using a largely inductive analytical framework the lived experienced of peritraumatic reactions spontaneously reported in interviews. Finally, building on these findings, I confirmed the theory-informed claims that the specific moments of a trauma experienced as intrusive memories would be characterised by higher levels of peritraumatic reactions compared to moments from the same trauma that did not intrude. All research was conducted among earthquake survivors. The current findings hold various implications for the conceptualisation of peritraumatic reactions and intrusive memories. Additionally, they have a number of practical implications for the prevention and management of intrusive memories as well as for the wellbeing of disaster survivors more generally.

This thesis details the rationale and methods for compiling a large individual patient data (IPD) dataset of adults treated for depression in primary care, for the purpose of identifying predictors of prognosis independent of treatment. I present a narrative review of the knowledge of factors associated with prognosis for adults with depression, a narrative review of the merits and difficulties of utilising IPD data, and a protocol for a series of systematic reviews with IPD meta-analyses seeking to meet the above aim. I then present three such IPD meta-analyses. These focus on the associations between depressed patient's pre-treatment characteristics, and i) prognosis independent of a range of treatments for depression in primary care, and ii) attrition from treatment. The first of these IPD meta-analyses is centred on depressive symptom severity and a group of factors that are associated with the degree of severity of a patient's experience of depression, but which are separate from depressive symptoms, (I refer to these as indicators of depressive 'disorder severity'). The second is centred on perceived social support. The third is centred on adverse life events in the six months prior to starting treatment, socio-demographics (age, gender, ethnicity, marital status, employment status, financial wellbeing, housing tenancy, and the highest level of educational attainment), and comorbid long-term physical health conditions. The thesis finishes with a critical review of the implications of these analyses, consideration of future directions and implications for clinical practice.

Huntington's Disease (HD) is a fatal, dominantly inherited neurodegenerative disorder caused by abnormal expansion of CAG trinucleotide repeats in the huntingtin gene. Here, we established two Drosophila melanogaster HD variants expressing either the Full-length (FL) or the Exon1 fragment (Ex1) of the human HTT gene. A series of behavioural experiments demonstrated that both these transgenic lines recapitulated the age-associated human HD symptoms. In recent years, altered miRNA expression has been increasingly recognised in human HD. MicroRNAs (miRNAs) are small non-coding RNA molecules that are involved in post transcriptional regulation of gene expression. Using bioinformatics, a subset of these differentially expressed human miRNAs that were evolutionary conserved with Drosophila were identified. Comparing the expression pattern of these miRNAs in human and Drosophila HD, it was discovered that few miRNAs displayed comparable change in expression. These results demonstrated that flies expressing Ex1 constructs were sufficient to replicate molecular and behavioural symptoms that were similar to the changes displayed by FL Drosophila and human HD patients. From the expression analysis, it was identified that miR-10 displayed a consistent expression in diseased HD flies and human HD model. An overexpression of miR-10 in non-HD flies led to severe locomotor defects which suggested that miR-10 is a part of the genetic elements that cause HD pathogenesis. Our results suggest that there might be a link between miR-10, locomotion and HD pathogenesis such that, if we reduce the upregulation of miR-10 in HD flies then we might restore the locomotor decline. miR-10 mutant and sponges were used for this investigation. We demonstrated that both the FL and the Ex1 constructs displayed modest improvement in locomotor abilities. It was also observed that the expression of miR-10 sponge was able to recover the survival rate of HD flies, suggesting that miR-10 expression in HD condition is associated with locomotion as well as survival. To explore the regulatory mechaimsms responsible for the altered miR-10 expression in HD flies, we short-listed transcription factors that were also differentially expressed in HD. The overall picture of data is valuable for investigating the role of miRNAs in HD condition.

Difficulty with certain areas of pragmatic language, for example engaging in back and forth conversation, are part of the diagnostic criteria for autism. That said, not all autistic children display every symptom described within these criteria. In addition, pragmatic language comprises a relatively heterogeneous set of skills. Hence, an impairment may not be present across all pragmatic language abilities for autistic individuals. Where difficulty does exist, the associated cognitive underpinnings are unclear. This thesis mainly focuses on one key pragmatic language skill, verbal reference, that is, the ability to identify the entity that is currently of interest between interlocutors via spoken language. In Chapter 2, broader pragmatic ability in autistic children is also examined using a parent report measure (the CCC-2). The findings of chapter 3, 4 and 5 indicate that autistic children are less able than well-matched typically developing peers to produce verbal reference that is tailored to listener needs. Chapters 3 and 4, however, suggest aspects of verbal reference interpretation are intact. Finally, chapters 2, 4 and 5 indicate that pragmatic language difficulties in autism, in particular the production of verbal reference, may be more related to executive functioning than social cognition ability. In sum, pragmatic language impairment might not be uniform within all areas of pragmatic language in autism. Categorising pragmatic abilities based upon the cognitive skills they recruit may improve understanding of areas of autistic strength and weakness in this diverse skill set.