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Background: It is widely accepted that borderline personality disorder (BPD) is associated with significant impairments in mentalization and theory of mind (ToM) which are considered as closely related concepts by many authors particularly in psychoanalytical circles. However, for understanding interpersonal difficulties in personality disorders, it is important to distinguish neuro-social cognitive impairment from the abnormal meta-social-cognitive style of patients. Methods: The current systematic review aimed to conduct separate meta-analyses of 'mentalization' [reflective functioning (RF] and different aspects of ToM in BPD. A literature search was conducted to locate relevant articles published between January 1990 to July 2021. Random-effect meta-analyses were conducted in 34 studies involving 1448 individuals with BPD and 2006 healthy controls. Results: A very large impairment in RF was evident in BPD [d = 1.68, confidence interval (CI) = 1.17–2.19]. In contrast, ToM impairment was modest (d = 0.36, CI = 0.24–0.48). BPD patients underperformed healthy controls in ToM-reasoning (d = 0.44, CI = 0.32–0.56) but not ToM-decoding. Increased HyperToM (d = 0.60, CI = 0.41–0.79) and faux pas recognition (d = 0.62, CI = 0.35–0.90) errors in BPD compared to healthy controls were most robust ToM findings in this meta-analysis. Conclusions: BPD is characterized by very severe deficits in RF and modest and selective abnormalities in ToM. Interpersonal problems and difficulties in processing social information in BPD can be best explained by patients' maldaptive meta-social cognitive style and top-down effects of these abnormalities rather than having a primary neuro-social cognitive deficit. [ABSTRACT FROM AUTHOR]

Minor physical anomalies (MPAs) are anatomical variations that are markers of aberrant early neurodevelopment. Schizophrenia is associated with increased MPA frequency, however, the frequency and distribution of MPAs exhibit substantial heterogeneity in schizophrenia and are not exclusive to this disorder. MPAs at different localizations might represent different developmental origins and might be related to latent genetic predisposition or vulnerability to develop full-blown psychosis. Therefore, we conducted a thorough review of minor physical anomalies (MPAs) in schizophrenia (Sch) and first-degree relatives (SchRel). Analyzing 52 studies published from January 1980 to October 2023, the meta-analysis compared MPA scores between 3780 schizophrenia patients and 3871 controls, as well as 1415 SchRel and 1569 controls. The total MPA score was significantly increased in schizophrenia compared to controls (g = 0.78 [0.63–0.93], p <0.001). In regional MPA meta-analyses, effect sizes ranged from 0.56 to 0.78. The difference between SchRel and controls was moderate (g = 0.44 [0.28–0.61], p <0.001). When individual MPA items were analyzed separately, fine electric hair, malformed ear, asymmetrical ear, curved 5th finger were anomalies that were shared between both schizophrenia and SchRel. Also, direct comparisons of the frequency of MPAs in schizophrenia and their relatives were conducted. Additionally, the early age of onset of schizophrenia was associated with mouth anomalies (Z =-2.13, p = 0.03), and ear anomalies were associated with a higher percentage of males in the schizophrenia group (Z = 2.64, p = 0.008). These findings support the notion that different MPAs might be associated with genetic susceptibility as well as vulnerability to developing full-blown psychosis. Studies investigating clinical and neurobiological correlates of MPAs in schizophrenia might be helpful in characterizing subtypes of psychoses that are associated with different developmental processes. [Display omitted] [ABSTRACT FROM AUTHOR]

Schizotypy is a multi-dimensional personality construct that putatively indicates an individual's liability to psychosis. Schizophrenia is associated with significant deficits in theory of mind (ToM). However, previous studies investigating the relationship between schizotypy and ToM provided inconsistent findings. Following the systematic review of all relevant schizotypy studies between January 1, 1980 and June 30, 2019, a meta-analysis of the relationship between ToM and schizotypy was conducted. Current meta-analysis included 24 studies consisting of 4162 healthy individuals. Overall, there was a significant but a small negative relationship between ToM and schizotypy (d = -0.23, CI = -0.14-0.33). Schizotypy scores were negatively associated with both reasoning (d = -0.24, CI = -0.11-0.38) and decoding (d = -0.21, CI = -0.09-0.32) aspects of ToM. The relationship between ToM and schizotypy was more significant in the studies using extreme-group design (d = -0.31, CI = -0.17-0.45) than non-extreme-group design (d = -0.17, CI = -0.04-0.29). ToM abnormalities were significantly related to both positive and negative schizotypy. Current findings support the continuum between schizotpy and schizophrenia. ToM abnormalities might be vulnerability markers for psychosis. [ABSTRACT FROM AUTHOR]

Background: Obsessive-compulsive disorder (OCD) has been associated with cognitive deficits, particularly with executive functions. These findings support fronto-striatal dysfunction in OCD. However, it is not certain whether these findings are trait features of OCD. In recent years, a number of studies have investigated cognitive functions in unaffected relatives of OCD (OCDrel) but the findings of these studies are contradictory. Methods: A systematic review in Pubmed and Scopus databases was performed until 18 March 2019, to locate the studies comparing cognitive functions of OCDrel with healthy controls and OCD patients (OCDpt). A random-effects meta-analysis was conducted. Results: Current meta-analysis included 16 studies including 527 OCDrel, 445 OCDpt and 639 healthy controls. Healthy controls overperformed OCDpt in all cognitive domains (d = 0.36–0.86). OCDrel underperformed healthy controls in inhibition (d = 0.58, CI = 0.29–0.86), planning (d = 0.45, CI = 0.28–0.63), decision-making (d = 0.58, CI = 0.19–0.98). OCDrel also had small-sized deficits in set-shifting (d = 0.37, CI = 0.04–0.69) and visual memory (d = 0.28, CI = 0.08–0.49). OCDpt underperformed OCDrel in visual memory (d = 0.45, CI = 0.22–0.67) and set-shifting (d = 0.23, CI = 0.04–0.42). Conclusions: Current findings suggest that abnormalities in inhibition, planning/problem solving and reward-based decision-making are shared features of OCDrel and OCDpt and might be trait markers related to vulnerability for developing OCD. Visual memory and set-shifting deficits might potentially be biomarkers of incipient illness or subthreshold OCD presentation among OCDrel. Further exploration of cognitive heterogeneity in OCDrel and investigating the effects of the subtypes of OCD in probands on cognitive impairment in OCDrel are needed. [ABSTRACT FROM AUTHOR]

Background: Schizophrenia is associated with significant cognitive impairment. However, the pathophysiological mechanisms underlying cognitive dysfunction in schizophrenia remain unclear. Brain-derived neurotrophic factor (BDNF) and C-reactive protein (CRP) are among the most commonly investigated peripheral markers of cognition in schizophrenia. Methods: A systematic review in PubMed and Scopus databases was performed until 31 January 2019 to assess the relationship between cognitive impairment, CRP and BDNF levels in schizophrenia. A random-effects meta-analysis was conducted. Results: Current meta-analysis included 21 studies including 2449 patients with schizophrenia-spectrum disorders. Overall, both BDNF [ r = 0.12, confidence interval (CI) 0.04–0.19] and CRP (r = −0.13, CI 0.08–0.18) levels were very modestly but significantly related to cognitive functioning in schizophrenia (r = 0.12, CI 0.04–0.19). In meta-analyses of cognitive domains, BDNF levels were significantly associated with verbal memory (r = 0.16, CI 0.09–0.23), working memory (r = 0.14, CI 0.06–0.22), processing speed (r = 0.18, CI 0.10–0.26) and verbal fluency (r = 0.09, CI 0–0.18) performances. Elevated CRP levels were related to all cognitive domains (r = −0.09 to −0.13) except for fluency. Subgroup analyses suggested that the relationship between cognitive and BDNF levels were more pronounced in chronic samples. Conclusions: Current findings suggest that cognitive impairment in schizophrenia is significantly related to elevated CRP and reduced BDNF levels in schizophrenia, particularly in chronic samples. However, small effect sizes of these correlations suggest that inflammation and decreased BDNF levels do not play a major role in cognitive dysfunction in most patients with schizophrenia. Further studies are needed to investigate the potential intermediating and confounding factors which can influence the level of relationship between inflammation, neurotrophic factors and cognition in schizophrenia. [ABSTRACT FROM AUTHOR]

Executive dysfunction and language impairment are the most prominent neuropsychological models of formal thought disorder (FTD) in schizophrenia. However, available studies have provided contradictory findings regarding the accuracy of these models. Furthermore, specific neurocognitive underpinnings of positive FTD (PosFTD) and negative FTD (NegFTD) are not clear. Following the systematic review of schizophrenia studies, a random-effects meta-analysis of the relationship between FTD and neurocognition/language in schizophrenia was conducted in 52 reports including 2805 patients. Neurocognition was significantly associated with both PosFTD (r = -0.21, CI = -0.14 to -0.27) and NegFTD (r = -0.24, CI = -0.18 to -0.30). Both PosFTD (r = ranged from -0.18 to -0.27) and NegFTD (r = ranged from -0.19 to -0.23) were significantly correlated with verbal memory, visual memory, attention, and processing speed. In meta-analyses of executive functions, PosFTD was significantly associated with working memory (r = -0.21), planning (r = -0.19), and inhibition (r = -0.21) and NegFTD was significantly associated with planning (r = -0.27), fluency (r = -0.27), and working memory (r = -0.24). In meta-analyses of linguistic variables, PosFTD was associated with deficits in syntactic comprehension (r = -0.27) and semantic processing (r = -0.18). In contrast, NegFTD was associated only with semantic comprehension (r = -0.21). Both PosFTD and NegFTD were significantly associated with executive dysfunction, neurocognitive deficits and semantic dysfunction but syntactic deficits were more specific to PosFTD. There were also some distinct patterns of relationships between the pattern of executive dysfunction and types of FTD. Fluency deficit was associated more strongly with NegFTD and poor inhibition was more specifically related to PosFTD. Current findings suggest that neurocognitive and linguistic correlates of PosFTD and NegFTD might be partly different. [ABSTRACT FROM AUTHOR]

Background: Individuals with bipolar disorder (BD) have a higher prevalence of obesity and metabolic syndrome (MetS) compared with the general population. Obesity and MetS are associated with cognitive deficits and brain imaging abnormalities in the general population. Obesity and components of MetS might potentially associate with neuroimaging and neurocognitive findings in BD. Methods: A literature search of studies investigating the association between obesity (and other components of MetS) and neurocognitive and neuroimaging findings in BD was conducted. In addition to a systematic review, a random-effects meta-analysis was conducted when sufficient data were available. Results: Twenty-three studies were included in the current systematic review. Overweight/obese patients were significantly associated with impaired neurocognition compared normal weight individuals with BD (d = 0.37). The most robust association between obesity and cognitive deficits in BD was observed in the cognitive subdomain of executive functions (d = 0.61). There was also evidence for a significant relationship between cognitive impairment in BD and other components of MetS including hypertension, dyslipidemia, and diabetes. Overweight/obese individuals with BD had more pronounced brain imaging abnormalities than normal weight individuals with BD. Conclusions: Obesity and related cardiovascular risk factors significantly are associated with more severe cognitive and brain imaging abnormalities in BD. Medical co-morbidities can potentially contribute to functional decline observed in some patients throughout the course of BD. [ABSTRACT FROM AUTHOR]

Abstract Neurological soft signs (NSS) are subtle deficits in motor coordination, sensory integration, and sequencing of complex motor acts. Increased NSS is a well-established feature of patients with schizophrenia but a relatively smaller number of studies have investigated NSS in bipolar disorder (BD). Some authors but not others suggested that NSS can distinguish schizophrenia from BD. We conducted a meta-analysis of 18 studies to quantitatively review NSS in BD in comparison to schizophrenia and healthy controls. The current meta-analysis compared NSS scores of 725 BD patients and 634 healthy controls, and 391 BD and 471 schizophrenia patients. Patients with BD had significantly higher NSS scores (d = 1.14, CI = 0.89–1.44) than healthy controls and increased scores in BD was evident in all aspects of NSS (d = 0.88–0.99). BD was associated with a less severe increase in NSS compared to schizophrenia, however, between-group difference was modest (d = 0.42, CI = 0.18–0.65). The results of this meta-analysis demonstrated that BD is characterized by a robust increase in NSS which is only moderately less severe than schizophrenia. Increased NSS is a common feature of both disorders. [ABSTRACT FROM AUTHOR]

Objective: There is a significant cognitive heterogeneity in bipolar disorder (BD). The aim of this systematic review was to examine the potential distinctive neuropsychological of features of clinical subgroups of BD. A literature search investigating cognitive differences between potential subtypes of BD was conducted.Methods: It was possible to conduct a meta-analysis of studies investigating the relationship between cognitive deficits and subgroups of DSM-IV BD (type I (BD-I) and type II (BD-II)), subgroups based on history of psychosis (PBD and NPBD). The cognitive domains investigated in this meta-analysis included verbal memory, visual memory, processing speed, executive functions speed (EF-speed), EF-accuracy, attention, working memory, social cognition. Current meta-analysis included 48 reports and compared cognitive performances of 1211 BD-I and 836 BD-II patients. It also compared cognitive functioning in 1017 PBD and 744 NPBD patients.Results: Both history of psychosis (d = 0.19) and BD-I (d = 0.17) diagnosis were associated with modestly more pronounced global cognitive impairment. In specific domains, BD-I significantly underperformed BD-II in verbal memory, processing speed, EF-speed, EF-accuracy (d = 0.15-0.26). PBD was associated with significantly impaired cognition compared to NPBD in verbal memory, processing speed, EF-speed, EF-accuracy, working memory and social cognition (d = 0.12-0.28).Conclusion: In BD, history of psychosis and full-manic episode are modestly associated with increased cognitive deficits. Neurocognitive differences between clinical subtypes of BD are quite subtle and are not distinctive. Furthermore, other factors reflecting differences in illness severity can explain observed between-group differences. Most of the cognitive heterogeneity in BD cannot be explained by proposed subtypes of BD. [ABSTRACT FROM AUTHOR]

Neurocognitive impairment is a well-established feature of first-episode psychosis (FEP). Neurotoxicity hypothesis of psychosis suggests that untreated psychosis before the initiation of first effective treatment is associated with loss of acquired cognitive abilities. However, the outcome of the studies investigating the relationship between duration of untreated psychosis (DUP) and cognitive impairment in FEP remains inconclusive. No previous meta-analysis investigating the relationship between DUP and cognitive impairment in FEP has been published. Following the systematic review of FEP studies, a random-effects meta-analysis of the relationship between DUP and neurocognition in schizophrenia was conducted. Current meta-analysis included 27 studies including 3127 patients with first-episode psychosis. Overall, DUP and cognitive abilities were not significantly related, with the exception of evidence for a weak relationship with a single cognitive domain. There was a very small but significant association between longer DUP and reduced performance in planning/problem-solving ability (r=-0.09, CI=-0.14 to -0.03). Current findings do not provide support for the neurotoxicity hypothesis of psychosis. [ABSTRACT FROM AUTHOR]

Social cognitive abilities are impaired in Alzheimer disease and other dementias. Recent studies suggested that social cognitive abilities might be also impaired in mild cognitive impairment (MCI). Current meta-analysis aimed to summarize available evidence for deficits in theory of mind (ToM) and emotion recognition in MCI. In this meta-analysis of 17 studies, facial emotion recognition and ToM performances of 513 individuals with MCI and 693 healthy controls were compared. Mild cognitive impairment was associated with significant impairments falling in the medium effect sizes range in ToM ( d = 0.63) and facial emotion recognition ( d = 0.58). Among individual emotions, recognition of fear and sadness were particularly impaired. There were no significant between-group differences in recognition of disgust, happiness, and surprise. Social cognitive deficits were more severe in multidomain MCI. There is a need for longitudinal studies investigating the potential role of social cognitive impairment in predicting conversion to dementia. [ABSTRACT FROM AUTHOR]

Historically, formal thought disorder has been considered as one of the distinctive symptoms of schizophrenia. However, research in last few decades suggested that there is a considerable clinical and neurobiological overlap between schizophrenia and bipolar disorder (BP). We conducted a meta-analysis of studies comparing positive (PTD) and negative formal thought disorder (NTD) in schizophrenia and BP. We included 19 studies comparing 715 schizophrenia and 474 BP patients. In the acute inpatient samples, there was no significant difference in the severity of PTD (d=-0.07, CI=-0.22-0.09) between schizophrenia and BP. In stable patients, schizophrenia was associated with increased PTD compared to BP (d=1.02, CI=0.35-1.70). NTD was significantly more severe (d=0.80, CI=0.52-0.1.08) in schizophrenia compared to BP. Our findings suggest that PTD is a shared feature of both schizophrenia and BP but persistent PTD or NTD can distinguish subgroups of schizophrenia from BP and schizophrenia patients with better clinical outcomes. [ABSTRACT FROM AUTHOR]

Background and aims: Deficits in social cognitive abilities including emotion recognition and theory of mind (ToM) can play a significant role in interpersonal difficulties observed in alcohol use disorder (AUD). This meta‐analysis aims to estimate mean effect sizes of deficits in social cognition in AUD and examines the effects of demographic and clinical confounding factors on the variability of effect sizes across studies. Methods: A literature review was conducted on research reports published from January 1990 to January 2016. Twenty‐five studies investigating ToM and facial emotion recognition performances of 756 individuals with AUD and 681 healthy controls were selected after applying inclusion and exclusion criteria. Weighted effect sizes (d) were calculated for ToM, decoding and reasoning aspects of ToM, total facial emotion recognition and recognition of each of six basic emotions. Results: Facial emotion recognition was significantly impaired [d = 0.65, 95% confidence interval (CI) = 0.42–0.89], particularly for disgust and anger. AUD was also associated with deficits in ToM (d = 0.58, 95% CI = 0.36–0.81). These deficits were evident in tasks measuring both decoding (d = 0.46, 95% CI = 0.19–0.73) and reasoning (d = 0.72, 95% CI = 0.37–1.06) aspects of ToM. The longer duration of alcohol misuse and more depressive symptoms were associated with more severe deficits in recognition of facial emotions. Conclusions: Alcohol use disorder appears to be associated with significant impairment in facial emotion recognition and theory of mind. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective Deficits in theory of mind (ToM), ability to infer mental states of others, can play a significant role in interpersonal difficulties and/or unawareness of illness observed in AN and other eating disorders including bulimia Nervosa (BN). Method Current meta-analysis aimed to summarize available evidence for deficits in ToM in AN and BN and examine the effects of number of study-level variables on observed findings. In this meta-analysis, 15 studies (22 samples with eating disorders) investigating ToM performances of 677 individuals with AN or BN and 514 healthy controls were included. Results AN was associated with significant deficits in ToM ( d = 0.59) which were more pronounced in the acute patients ( d = 0.67). Small sized deficits in ToM were observed in BN ( d = 0.34) and recovered AN ( d = 0.35). Both cognitive perspective-taking (ToM-PT) ( d = 0.99) and decoding mental states (ToM-decoding) ( d = 0.61) aspects of ToM were impaired in acute AN. ToM-decoding impairment in BN was modest. There was no evidence for significant ToM-PT deficit in BN. Several study-level variables including longer duration of illness, lower BMI, and depressive symptoms were associated with more severe deficits in ToM in AN. Discussion ToM deficits, particularly in ToM-PT, can be a specific feature of AN but not BN. ToM impairment can contribute to poor insight, treatment resistance, and social impairment in AN. © 2016 Wiley Periodicals, Inc. RESUMEN Meta análisis de la teoría de la mente en anorexia nervosa y bulimia nervosa ¿Un deterioro de la toma de perspectiva cognitiva en Anorexia Nervosa? Objetivo Las deficiencias en la teoría de la mente (ToM), la habilidad parar inferir los estados mentales de otros, pueden jugar una función significativa en las dificultades interpersonales y/o falta de reconocimiento de la enfermedad observada en Anorexia Nervosa (AN) y otros trastornos de la conducta alimentaria incluyendo la Bulimia Nervosa (BN). Método Los meta análisis actuales dirigidos a resumir la evidencia disponible sobre el déficit en ToM en AN y BN y examinar los efectos de un número de variables a nivel estudio en los resultados observados. En este meta análisis fueron incluidos 15 estudios (22 muestras con trastornos alimenticios) investigando la función de ToM de 677 individuos con AN o BN y 514 controles sanos. Resultados La AN fue relacionada con déficit significativo en ToM (d=0.59) los cuales fueron pronunciados en los pacientes agudos (d=0.67). Se observaron déficits de tamaño pequeño en BN (d=0.34) y AN recuperada (d=0.35). La toma de perspectiva cognitiva (ToM-PT) (d=0.99) y la descodificación de los procesos mentales (descodificación de ToM) (d=0.61) fueron deteriorados en la AN aguda. El deterioro en la descodificación de ToM en BN fue moderado. No se encontró evidencia significativa de déficit en ToM-PT en BN. Algunas variables a nivel estudio incluyendo la larga duración de la enfermedad, índice de masa corporal (IMC) bajo y síntomas depresivos fueron asociados con mayores déficit severos en ToM en AN. Discusión El déficit en ToM, particularmente en ToM-PT puede ser una característica específica en la AN pero no en la BN. El deterioro en la descodificación de ToM puede contribuir a mala percepción, resistencia al tratamiento y deterioro social en AN. © 2016 Wiley Periodicals, Inc.(Int J Eat Disord 2016; 49:739-749) [ABSTRACT FROM AUTHOR]

Objective: Cognitive dysfunction is a common characteristic of both schizophrenia and bipolar disorder (BP). While these deficits are more severe in schizophrenia, there is a significant overlap between conditions. However, it was hypothesized that social cognitive deficits might be more specific to schizophrenia.Methods: We conducted a meta-analysis of studies comparing facial emotion recognition and theory of mind (ToM) abilities in schizophrenia and BP. 26 studies comparing 1301 patients with schizophrenia and 1075 with BP were included.Results: Schizophrenia patients significantly underperformed compared with BP patients in both facial emotion recognition (d=0.39) and ToM (d=0.57). Neurocognitive deficits significantly contributed to schizophrenia-BP group differences for ToM. However, between-group differences for social cognition were not statistically more severe than neurocognition.Conclusion: Social cognitive impairment is more severe in schizophrenia in comparison to BP. However, between-group differences are modest and are comparable to other neurocognitive differences between schizophrenia and BP. There is significant overlap in social cognitive performance deficits observed in both schizophrenia and BP. [ABSTRACT FROM AUTHOR]

Objective There is increasing evidence suggesting that social cognitive abilities are impaired in temporal lobe epilepsy (TLE), the most common form of focal epilepsies. Methods In this meta-analysis, 31 studies investigating theory of mind (ToM) and facial emotion recognition performances of 1356 patients with TLE (351 postsurgery) and 859 healthy controls were included. Results Patients with TLE had significant deficits in ToM ( d = 0.73–0.89) and recognition of facial emotions. There were no significant differences in severity of social cognitive deficits between patients with TLE with or without medial temporal lobectomy. Earlier onset of seizures was associated with ToM impairment. Right-sided TLE was associated with more severe deficits in recognition of fear, sadness, and disgust. Conclusions Social cognitive information processing is impaired in TLE, and the potential role of these deficits in functional impairment needs to be further investigated. [ABSTRACT FROM AUTHOR]

Behavioral disturbances and lack of empathy are distinctive clinical features of behavioral variant frontotemporal dementia (bvFTD) in comparison to Alzheimer disease (AD). The aim of this meta-analytic review was to compare facial emotion recognition performances of bvFTD with healthy controls and AD. The current meta-analysis included a total of 19 studies and involved comparisons of 288 individuals with bvFTD and 329 healthy controls and 162 bvFTD and 147 patients with AD. Facial emotion recognition was significantly impaired in bvFTD in comparison to the healthy controls (d = 1.81) and AD (d = 1.23). In bvFTD, recognition of negative emotions, especially anger (d = 1.48) and disgust (d = 1.41), were severely impaired. Emotion recognition was significantly impaired in bvFTD in comparison to AD in all emotions other than happiness. Impairment of emotion recognition is a relatively specific feature of bvFTD. Routine assessment of social-cognitive abilities including emotion recognition can be helpful in better differentiating between cortical dementias such as bvFTD and AD. [ABSTRACT FROM AUTHOR]

Objective: Social cognitive deficits can contribute to risk for depression and to psychosocial impairment during depression. However, available evidence suggests that emotion recognition is only marginally impaired in major depressive disorder (MDD). Recent studies have investigated theory of mind (ToM) abilities, a cognitively more demanding aspect of social cognition.Methods: We conducted a meta-analysis of studies comparing ToM abilities in MDD and healthy controls. 18 studies comparing 613 patients with MDD and 529 healthy controls were included.Results: MDD patients significantly underperformed healthy controls in ToM (d=0.51-0.58). ToM impairment in MDD was evident in response to different types of ToM tasks (verbal/visual and cognitive/affective and reasoning/decoding). ToM impairment was significantly related to severity of depressive symptoms.Conclusion: Theory of mind abilities are impaired during depression and can potentially contribute to psychosocial difficulties during depression. There is a need to investigate ToM abilities in different subtypes and stages of depression, especially in remitted patients. [ABSTRACT FROM AUTHOR]

Neurocognitive impairment in Huntington’s disease (HD) frequently includes deficits in emotion recognition, and recent studies have also provided evidence for deficits in theory of mind (ToM). There have been conflicting reports regarding the extent of emotion recognition and ToM deficits before the onset of motor symptoms in HD. In this meta-analysis, ToM and emotion recognition performances of 2226HD or pre-manifest HD and 998 healthy controls were included in the meta-analysis. Meta-regression analyses were conducted to investigate the relationship between social cognition deficits and demographic, cognitive and clinical features in HD. HD patients were significantly less accurate than controls in ToM and across all emotions in response to both facial and vocal stimuli. ToM ( d = 1.72) and recognition of negative emotions ( d = 1.20–1.33), especially anger, disgust and fear ( d = 1.26–1.52) were severely impaired. Pre-manifest HD was also associated with impairment in social cognition. The severity of emotion recognition impairment was significantly associated with disease burden, proximity of onset of motor symptoms and cognitive impairment. Social cognition impairments are potential biomarkers of disease onset and progression in HD. [ABSTRACT FROM AUTHOR]

Non-motor symptoms of Parkinson’s disease (PD) include cognitive deficits and impairment in the recognition of emotions. Recently, a number of studies have investigated theory of mind (ToM) deficits in PD. In this meta-analysis of 18 studies, the ToM performance of 487 non-demented individuals with Parkinson’s disease (PD) was compared with 459 healthy controls. Meta-regression analyses were conducted to investigate the relationship between ToM deficits and demographical and clinical features in PD, including medication, stage of the illness and neurocognition. PD was associated with significant ToM impairment ( d = 0.83) in both verbal and visual tasks. In individual task analyses, PD patients performed worse than controls in both faux pas recognition ( d = 0.55) and reading the mind from the eyes ( d = 0.67) tests. Severity of ToM impairment was significantly associated with cognitive impairment. Impairments in social cognitive abilities, including ToM, may be important contributors to the functional impairments observed in PD. [ABSTRACT FROM AUTHOR]

Neurocognitive deficits are evident both in established schizophrenia and bipolar disorder (BP). However, it has been suggested that schizophrenia, but not BP, is characterized by neurodevelopmental abnormalities that can lead to cognitive deficits at the earliest stages of the illness. The aim of this meta-analytic review was to compare neurocognitive deficits in first-episode BP (FEBP) with healthy controls and first-episode schizophrenia (FES) patients. The current meta-analysis included a total of 22 adult studies and involved comparisons of 533 FEBP patients with 1417 healthy controls and 605 FEBP and 822 FES patients. FEBP patients were significantly impaired in all cognitive domains (d = 0.26- 0.80) and individual tasks (d = 0.22-0.66) investigated. FES patients significantly underperformed FEBP patients in most cognitive domains (d = 0.05-0.63) and on individual tasks (d = 0.13-0.77). Neuropsychological impairment, which is comparable to chronic BP, was evident in FEBP. Similar to chronic patients, cognitive functions in FEBP lie intermediate between FES and healthy controls. Neurodevelopmental factors are likely to play a significant role not only in schizophrenia but also in BP. [ABSTRACT FROM AUTHOR]

Cognitive dysfunction is a well-established feature of schizophrenia, and there is evidence suggesting that cognitive deficits are secondary to abnormal neurodevelopment leading to problems in acquiring such abilities. However, it is not clear whether there is also a decline in cognitive performance over, or after, the onset of psychosis. Our objective was to quantitatively examine the longitudinal changes in cognitive function in patients who presented with first-episode psychosis (FEP), ultra-high risk (UHR) for psychosis, and controls. Electronic databases were searched for the studies published between January 1987 and February 2013. All studies reporting longitudinal cognitive data in FEP and UHR subjects were retrieved. We conducted meta-analyses of 25 studies including 905 patients with FEP, 560 patients at UHR, and 405 healthy controls. The cognitive performances of FEP, UHR, and healthy controls all significantly improved over time. There was no publication bias, and distributions of effect sizes were very homogenous. In FEP, the degree of improvement in verbal working memory and executive functions was significantly associated with reduction in negative symptoms. There was no evidence of cognitive decline in patients with UHR and FEP. In contrast, the cognitive performances of both groups improved at follow-up. These findings suggest that cognitive deficits are already established before the prodromal phases of psychosis. These data support the neurodevelopmental model rather than neurodegenerative and related staging models of schizophrenia. [ABSTRACT FROM PUBLISHER]

Abstract: Theory of mind (ToM) deficit is a well-established feature of schizophrenia and has been suggested as a vulnerability marker of this disorder. However, as most of this evidence is based on studies in chronic patients, it is less clear whether ToM is impaired prior to or following the onset of a first-episode and whether it is evident in unaffected relatives of patients. In this meta-analysis, ToM performance of 3005 individuals with first-episode psychosis (FEP), individuals at ultra-high risk for psychosis (UHR) and unaffected relatives were compared with 1351 healthy controls. ToM was substantially impaired in first-episode psychosis (Cohen d =1.0) and this deficit was comparable to findings in chronic patients. ToM was also impaired in unaffected relatives (d =0.37) and UHR subjects (d =0.45) and performances of these groups were intermediate between FES and healthy controls. Severity of ToM deficits in unaffected relatives and UHR subjects was similar to other cognitive deficits observed in these groups. Longitudinal studies of clinical and genetic high-risk subjects are necessary to investigate the trajectory of development of ToM deficits in schizophrenia. [Copyright &y& Elsevier]

Abstract: Background: Voxel-based morphometry (VBM) has been widely used to quantify structural brain changes associated with Major Depressive Disorder (MDD). While some consistent findings have been reported, individual studies have also varied with respect to the key brain regions affected by the illness, and how these abnormalities are related to patients'' clinical characteristics. Here, we aimed to identify those brain regions that most consistently showed gray matter anomalies in MDD, and their clinical correlates, using meta-analytic techniques. Methods: A systematic search of VBM studies was applied in MDD. Signed differential mapping, a new coordinate based neuroimaging meta-analysis technique, was applied to data collated from a total of 23 studies comparing regional gray matter volumes of 986 MDD patients and 937 healthy controls. Results: Gray matter was significantly reduced in a confined cluster located in the rostral anterior cingulate cortex (ACC). There were also gray matter reductions in dorsolateral and dorsomedial prefrontal cortex and decrease in the latter region was evident in patients with multiple-episodes. Amygdala and parahippocampal gray matter volumes were significantly reduced in studies including patients with comorbid anxiety disorders, as well as in first-episode/drug free samples. Conclusions: Gray matter reduction in rostral ACC was the most consistent finding in VBM studies of MDD. The evidence for reductions in other regions within fronto-subcortical and limbic regions was less consistent. The associations between these gray matter anomalies and clinical characteristics, particularly measures relating to illness duration, suggest that chronic MDD has a robust and deleterious, albeit spatially focal, effect on brain structure. [Copyright &y& Elsevier]

Abstract: Despite an increasing number of published voxel based morphometry studies of schizophrenia, there has been no adequate attempt to examine gray (GM) and white matter (WM) abnormalities and the heterogeneity of published findings. In the current article, we used a coordinate based meta-analysis technique to simultaneously examine GM and WM abnormalities in schizophrenia and to assess the effects of gender, chronicity, negative symptoms and other clinical variables. 79 studies meeting our inclusion criteria were included in the meta-analysis. Schizophrenia was associated with GM reductions in the bilateral insula/inferior frontal cortex, superior temporal gyrus, anterior cingulate gyrus/medial frontal cortex, thalamus and left amygdala. In WM analyses of volumetric and diffusion-weighted images, schizophrenia was associated with decreased FA and/or WM in interhemispheric fibers, anterior thalamic radiation, inferior longitudinal fasciculi, inferior frontal occipital fasciculi, cingulum and fornix. Male gender, chronic illness and negative symptoms were associated with more severe GM abnormalities and illness chronicity was associated with more severe WM deficits. The meta-analyses revealed overlapping GM and WM structural findings in schizophrenia, characterized by bilateral anterior cortical, limbic and subcortical GM abnormalities, and WM changes in regions including tracts that connect these structures within and between hemispheres. However, the available findings are biased towards characteristics of schizophrenia samples with poor prognosis. [Copyright &y& Elsevier]

Background: We conducted a meta-analysis of gray matter abnormalities in bipolar disorder (BD) using voxel-based morphometry studies to help clarify the structural abnormalities underpinning this condition. Methods: A systematic review was conducted for voxel-based morphometry studies of patients with BD. Meta-analyses of gray matter differences between BD and control subjects were undertaken using “signed differential mapping,” a novel method that, in contrast to previously used techniques, allows inclusion of negative findings and ensures that single studies do not exert undue influence on the results. Meta-regression and subgroup analyses were used to examine the effect of moderator variables on gray matter abnormalities. Results: A total of 21 studies comparing gray matter volumes of 660 BD patients and 770 healthy control subjects were included. Gray matter reduction in left rostral anterior cingulate cortex (ACC) and right fronto-insular cortex was associated with BD. Fronto-insular cortex abnormality was not evident in early phases of the illness. In chronic patients, longer duration of illness was associated with increased gray matter in a cluster that included basal ganglia, subgenual ACC, and amygdala. Lithium treatment was associated with enlargement of ACC gray matter volumes, which overlapped with the region where gray matter was reduced in BD. Conclusions: The most robust gray matter reductions in BD occur in anterior limbic regions, which may be related to the executive control and emotional processing abnormalities seen in this patient population. Clinical factors such as illness duration and lithium treatment also impact on case-control comparisons of gray matter volume. [Copyright &y& Elsevier]

Background Cognitive functioning in affective psychosis and schizoaffective disorder is much less studied compared with schizophrenia. Aims To quantitatively undertake a meta-analysis of the available data that directly compares cognitive functioning across schizophrenia, schizoaffective disorder and affective psychosis. Method Following a thorough literature review, 31 studies that compared the performances of people with schizophrenia (1979 participants) with that of those with affective psychosis or schizoaffective disorder (1314 participants) were included. To determine the effect of demographic and clinical confounders, meta-regression and subgroup analyses were conducted. Results In 6 of 12 cognitive domains, people with schizophrenia performed worse than people with schizoaffective disorder or affective psychosis. However, the between-group differences were small and the distribution of effect sizes showed substantial heterogeneity. The between-group differences were driven by a higher percentage of males, more severe negative symptoms and younger age at onset of illness in the schizophrenia samples. Conclusions Neuropsychological data do not provide evidence for categorical differences between schizophrenia and other groups. However, a subgroup of individuals with schizophrenia who have more severe negative symptoms may be cognitively more impaired than those with affective psychosis/schizoaffective disorder. Declaration of interest None. [ABSTRACT FROM AUTHOR]

Abstract: There is now substantial evidence for Theory of mind (ToM) impairment in schizophrenia. Despite this, we know little about how dynamic (state) variables and broad clinical, cognitive and medication characteristics moderate the precise magnitude of the observed ToM deficit during task performance. Meta-analyses were conducted using 36 studies that reported continuous data regarding ToM performances of schizophrenia patients and healthy control subjects. These 36 studies included 1,181 (67% male) patients with schizophrenia and 936 (58.3% male) healthy control subjects. Individual analyses were also conducted for the Hinting and the Eyes tasks. The effects of moderator variables were studied by both subgroup and meta-regression analyses. The effect sizes (Cohen''s d) for overall ToM performance and the individual tasks were large (d =0.90–1.08). In “remitted” patients, the degree of ToM impairment was less pronounced than non-remitted patients (d =1.21) but it was still significant (d =0.80). Moreover, the distribution of effect sizes was more homogeneous for the individual tasks, especially in “remitted” patients. General intellectual deficits observed in schizophrenia patients contributed to their ToM impairment only in the remission phase of the illness. While state variables and task specific differences explain a large degree of the heterogeneity of the ToM findings observed in previous studies, the persistence of ToM deficits in “remitted” patients suggests there are trait related mentalising impairments in schizophrenia. Our review also suggests that future research should consider the potential moderating influence of IQ deficits on ToM performance in “remitted” patients, as well as the potential effects of residual symptoms. [Copyright &y& Elsevier]

Abstract: Background: Our aim was to delineate neuropsychological deficits related to genetic susceptibility, illness process and iatrogenic factors in bipolar disorder (BD). Methods: Following an extensive publication search on several databases, meta-analyses were conducted for 18 cognitive variables in studies that compared performances of euthymic BD patients (45 studies; 1423 subjects) or first-degree relatives of BD patients (17 studies; 443 subjects) with healthy controls. The effect of demographic variables and confounding factors like age of onset, duration of illness and medication status were analysed using the method of meta-regression. Results: While response inhibition, set shifting, executive function, verbal memory and sustained attention deficits were common features for both patient (medium to large effect sizes) and relative groups (small to medium effect sizes), processing speed, visual memory and verbal fluency deficits were only observed in patients. Medication effects contributed to psychomotor slowing in BD patients. Earlier age of onset was associated with verbal memory impairment and psychomotor slowing. Limitation: Data related to some confounding variables was not reported in a substantial number of extracted studies. Conclusions: Response inhibition deficit, a potential marker of ventral prefrontal dysfunction, seems to be the most prominent endophenotype of BD. The cognitive endophenotype of BD also appears to involve fronto-temporal and fronto-limbic related cognitive impairments. Processing speed impairment is related, at least partly, to medication effects indicating the influence of confounding factors rather than genetic susceptibility. Patterns of sustained attention and processing speed impairments differ from schizophrenia. Future work in this area should differentiate cognitive deficits associated with disease genotype from impairments related to other confounding factors. [Copyright &y& Elsevier]