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Memory is better for emotional rather than neutral events or materials (emotional enhancement of memory; EEM). Evidence suggests that this memory benefit remains intact in schizophrenia, but conflicting findings present the need for further research to understand how and when this process occurs. Here, we examine whether different encoding methods for learning emotional faces may result in different EEM patterns in those with schizophrenia spectrum disorders (SSD). A patient group (n = 28) and healthy comparisons (n = 29) encoded faces in two conditions that manipulated attentional focus to promote direct (emotion judgements) or indirect (sex discrimination) processing of emotional content. Based on literature in schizophrenia showing selective emotion perception deficits on tasks of direct processing but relatively intact emotion perception on indirect processing tasks, we hypothesized that patients would show greater EEM effects when faces were encoded indirectly. This hypothesis was not supported, and the patient group instead showed a similar intact EEM for angry and fearful faces to healthy comparisons in both encoding conditions. Further, using the Remember/Know paradigm, we demonstrated that the EEM in SSD appears selective to recollection-based memory, which helps to explain inconsistencies in past literature that has not differentiated between recognition domains. These findings have important implications for improving emotional memory and functional outcomes in SSD; future research should establish how the EEM for facial expressions may relate to social functioning.

Previous work has shown recognition of emotional facial expressions may differentially relate to task demands, such as whether one indirectly or directly encodes the emotional information. Given gender differences in emotion processing and memory, we assessed whether participant gender might moderate these encoding task effects. Using a between-subjects design with a sample of 100 undergraduates, participants made judgments about the gender (indirect) or emotion (direct) of facial stimuli displaying fearful, angry, happy, and neutral expressions. Different task-related effects were observed by gender for faces accompanied by recollection, as measured with the Remember-Know paradigm. Namely, women demonstrated better memory discrimination for emotional facial expressions only for remember responses following indirect encoding, whereas this effect was not significant for men. These results highlight the importance of considering participant gender, type of encoding task, and level of recollection on emotional memory for faces. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Posttraumatic stress disorder (PTSD) is a prevalent psychiatric disorder that can result from experiencing traumatic events. Accurate diagnosis and optimal treatment strategies can be difficult to achieve, due to the heterogeneous etiology and symptomology of PTSD, and overlap with other psychiatric disorders. Advancing our understanding of PTSD pathophysiology is therefore critical. While functional connectivity alterations have shown promise for elucidating the neurobiological mechanisms of PTSD, previous findings have been inconsistent. Eleven patients with PTSD in our first cohort (PTSD-A) and 11 trauma-exposed controls (TEC) underwent functional magnetic resonance imaging. First, we investigated the intrinsic connectivity within known resting state networks (eg, default mode, salience, and central executive networks) previously implicated in functional abnormalities with PTSD symptoms. Second, the overall topology of network structure was compared between PTSD-A and TEC using graph theory. Finally, we used a novel combination of graph theory analysis and scaled subprofile modeling (SSM) to identify a disease-related, covarying pattern of brain network organization. No significant group differences were found in intrinsic connectivity of known resting state networks and graph theory metrics (clustering coefficients, characteristic path length, smallworldness, global and local efficiencies, and degree centrality). The graph theory/SSM analysis revealed a topographical pattern of altered degree centrality differentiating PTSD-A from TEC. This PTSD-related network pattern expression was additionally investigated in a separate cohort of 33 subjects who were scanned with a different MRI scanner (22 patients with PTSD or PTSD-B, and 11 healthy trauma-naïve controls or TNC). Across all participant groups, pattern expression scores were significantly lower in the TEC group, while PTSD-A, PTSD-B, and TNC subject profiles did not differ from each other. Expression level of the pattern was correlated with symptom severity in the PTSD-B group. This method offers potential in developing objective biomarkers associated with PTSD. Possible interpretations and clinical implications will be discussed.

Background Insomnia is a major predictor of adverse outcomes in mild traumatic brain injury (mTBI), including concussion; although insomnia symptoms may be due to various sleep disorders, those related to circadian rhythm sleep-wake disorders (CRSWDs) require specific assessment and treatment. The objective of the current study was to determine the prevalence of CRSWD in a sample of treatment-seeking people with chronic insomnia symptoms after an mTBI. Methods Participants aged 17-65 years who had experienced an mTBI and reported chronic insomnia were recruited from diverse community clinics in Ontario 3-24 months after their injury to participate in this cross-sectional observational study. Potential participants were screened by both telephone and intake interview. Exclusion criteria were alcohol or substance use disorders, preexisting brain disorder or previous neurosurgery, recent travel across more than 2 time zones or shift work. Assessments included a clinical interview, questionnaires, 2 weeks of actigraphy and a sleep diary, and a dim-light melatonin onset test. The main outcome measure was the proportion of patients with CRSWDs. Results Of the 50 participants (32 [64%] female; median age 39.5 yr), 13 (26% [standard deviation 12%]) had an CRSWD. The most common circadian diagnosis was delayed sleep-wake phase disorder (10 participants [20%]). Interpretation The prevalence of CRSWDs may be exceptionally high among people with chronic insomnia symptoms following mTBI. Proper detection and treatment of CRSWDs in this population is essential to facilitate recovery. The findings emphasize the relevance of a diagnostic circadian assessment in patients with mTBI presenting with chronic insomnia symptoms.

Hoarding disorder is characterized by difficulty discarding objects and excessive clutter. The relationship between hoarding and claustrophobia, reactions to severely cluttered spaces, and clutter preferences are all areas that are yet to be investigated. The present study used a novel virtual reality (VR) platform to examine these domains. Two groups (i.e., with hoarding disorder

Paranoia exists on a continuum with normal experience. Worry has been identified as a risk variable for paranoid thinking within non-clinical populations; however, studies have focused exclusively on the association between worry and persecutory beliefs, despite paranoia encompassing other domains (interpersonal sensitivities, mistrust, ideas of reference). Further, it is possible that worry-related processes account for more variance in paranoia than does the general tendency to worry. This study examined the associations of worry, intolerance of uncertainty (IU), and negative urgency (NU) to the four aforementioned domains of paranoia. N = 311 undergraduate students completed self-report measures. Worry, IU, and NU were most strongly correlated with ideas of social reference and interpersonal sensitivities. Only IU and NU emerged as significant unique correlates of all domains of paranoid thinking when controlling for worry. Results suggest that the associations between worry and paranoia may be better explained by underlying processes, particularly IU. Future research should examine the association of other worry-related processes to paranoia, as well as the interactions between these processes and other diatheses (e.g., negative beliefs about self and others) in the generation of paranoia.

Background: Posttraumatic stress disorder (PTSD) is associated with abnormal hippocampal activity; however, the functional connectivity (FC) of the hippocampus with other brain regions in PTSD and its relations with symptoms warrants further attention. We investigated subregional hippocampal FC in PTSD during a resting state compared with a trauma-exposed control (TEC) group. Based on extant research, we targeted the FCs of the anterior and posterior hippocampal subregions with the amygdala, medial prefrontal cortex (mPFC), and the posterior cingulate (PCC). Methods: Resting-state functional magnetic resonance images were acquired from 11 individuals with PTSD and 13 trauma-exposed controls. Anterior and posterior hippocampal FC was compared between groups. Within the PTSD and TEC groups, subregional hippocampal FC was correlated with scores on the Clinician-Administered PTSD Scale (CAPS) at time of scan and 4 months post-scan. Results: Those with PTSD had significantly greater FC compared with the TEC group between the left posterior hippocampus and the bilateral PCC (g’s > .96). Direct contrasts of the Fisher z-transformed coefficients indicated that the correlations between CAPS scores 4 months post scan and the FC between the left hippocampal head and the right PCC (z = − 2.07, p = .039) as well as the FC between the right hippocampal tail and the right mPFC (z = − 2.19, p= .029) were significantly greater in the PTSD group compared to the TEC group. Conclusions: These results support between-group differences in posterior hippocampal FC and different relations with PTSD future symptoms, underscoring associations with the anterior and posterior hippocampus. These findings enrich our understanding of PTSD pathophysiology and provide support for future investigations of imaging biomarkers predictive of disease progression. Keywords: Posttraumatic stress disorder, Functional magnetic resonance imaging, Hippocampus, Trauma symptoms, Resting state connectivity

Different strategies may be spontaneously adopted to solve most navigation tasks. These strategies are associated with dissociable brain systems. Here, we use brain-imaging and cognitive tasks to test the hypothesis that individuals living with Schizophrenia Spectrum Disorders (SSD) have selective impairment using a hippocampal-dependent spatial navigation strategy. Brain activation and memory performance were examined using functional magnetic resonance imaging (fMRI) during the 4-on-8 virtual maze (4/8VM) task, a human analog of the rodent radial-arm maze that is amenable to both response-based (egocentric or landmark-based) and spatial (allocentric, cognitive mapping) strategies to remember and navigate to target objects. SSD (schizophrenia and schizoaffective disorder) participants who adopted a spatial strategy performed more poorly on the 4/8VM task and had less hippocampal activation than healthy comparison participants using either strategy as well as SSD participants using a response strategy. This study highlights the importance of strategy use in relation to spatial cognitive functioning in SSD. Consistent with a selective-hippocampal dependent deficit in SSD, these results support the further development of protocols to train impaired hippocampal-dependent abilities or harness non-hippocampal dependent intact abilities.

Background and objectives Delusions of reference are thought to reflect abnormally heightened attributions of salience to mundane events or stimuli that lead to convictions that they are personally significant or directed at the observer. Recent findings highlight abnormal recruitment of brain regions associated with self-referential processes among patients with referential delusions. Given the inherent overlap of emotion, incentive salience, and self-relevance, as well as with aberrant thought processes in psychosis, this study investigated the implicit relations between participants’ perception of the emotional valence of stimuli on neural correlates of self-referent judgments among schizophrenia-spectrum patients with referential delusions. Methods During fMRI scanning, participants indicated whether sentences describing personal characteristics seemed to refer specifically to them. Subsequently, participants rated their perceived emotional valence of each statement. Results Regression analyses revealed differential relations between groups across regions associated with self-referential processing, including prefrontal regions, anterior cingulate, insula, precuneus, and dorsal striatum. Within these regions, greater activation related to sentences rated as more positive among healthy comparison participants and more negative among patients. Limitations The current results warrant replication and extension with larger and longitudinal samples to assess potential moderating relations of clinical and demographic individual differences. Conclusions These findings support aberrant brain activation associated with emotional and salience brain networks in schizophrenia and highlight the importance of considering specific emotional attributes (valence) in discrete domains of delusional thought (self-referential communication).

HIV continues to be a stigmatized disease, despite significant advances in care and concerted effort to reduce discrimination, stereotypes, and prejudice. Living with HIV is often associated with a multitude of overlapping and intersecting experiences which can, in and of themselves, also be stigmatized, and which may exacerbate HIV-related stigma. The consequences of these stigmatizing experiences are particularly impactful when the stigmatizing individual is a health care provider, as this can influence access to and quality of care. The current study empirically investigates a model of overlapping stigmas (homophobia, racism, sexism, stigma against injection drug use and stigma against sex work) potentially held by health care provider trainees in Canada to determine how these constructs overlap and intersect, and to assess whether HIV-related stigma may have unique attributes. Understanding overlapping stigmas can help inform targeted, stigma-informed training for health care trainees in order to provide effective, compassionate care for people living with HIV.

In this paper, we examine the dynamic nature of the resilience process as an interaction between individuals and their larger socio-ecological context. We introduce a novel, multi-systems model of resilience that addresses limitations within existing models, clarifies ambiguity brought on by heterogeneous definitions of resilience, and recognizes resilience as a process across the lifespan. This model includes intra-individual, interpersonal, and socio-ecological variables, and highlights the interactive process of resilience that is dynamic and multi-dimensional in nature.

Why are some people more religious than others? According to one hypothesis, people who strongly seek definitive explanations for situations with incomplete information are more likely to be religious. According to a different hypothesis, individuals with smaller "prediction error" responses to unexpected stimuli are more likely to discount evidence contradicting religious beliefs, predisposing them to maintain such beliefs. We sought neurophysiological evidence for these hypotheses using the N400 event-related potential (ERP), which is smaller to more contextually expected stimuli, reflecting prediction of probable completions for meaningful situations. We recorded ERPs from participants viewing category definitions followed by high-typicality category exemplar (HTE), low-typicality exemplar (LTE), or non-exemplar (NE) words. As expected, N400s were largest for NEs, intermediate for LTEs, and smallest for HTEs. Religiosity correlated with smaller N400 amplitude differences between HTEs and both LTEs and NEs. Less strong prediction of probable stimuli based on prior information may predispose to religiosity.

Spatial memory is core to wayfinding and everyday memory. Interestingly, individuals with schizophrenia using spatial navigation strategies (cognitive mapping) are impaired, whereas those using response-based (e.g., single-landmark) strategies show relatively intact memory performance. We observed abnormal brain communication in schizophrenia participants who used a spatial strategy during a virtual-reality navigation task, particularly between temporal and frontal brain regions. In contrast, schizophrenia participants using a response strategy recruited similar brain systems to healthy participants, but to a greater extent to support memory performance. These findings highlight that strategy use is an important consideration for understanding memory systems and navigation in schizophrenia.

Repetitive transcranial magnetic stimulation (rTMS) is thought to modulate brain function through methods of electromagnetic induction. Over the last few decades, a large body of studies have investigated the clinical applications of rTMS in a variety of patient populations for a diverse range of symptoms from depressive symptomology to post-stroke motor functioning. There is still no clear consensus, however, on how rTMS influences cognitive functioning in the healthy brain. We conducted a quantitative meta-analysis in order to evaluate whether offline rTMS (the delivery of rTMS when not actively engaged in a cognitive task) influences cognition in healthy adults. More specifically, we examined studies that applied rTMS to the dorsal lateral prefrontal cortex (DLFPC) and that tracked cognitive outcomes both before and after a prescribed period of rTMS. Fifteen studies met our inclusion criteria. Cognitive performance was pooled and examined across studies for four cognitive domains (working memory, executive functioning, episodic memory, and visual perception) and under two types of stimulation conditions (excitatory and inhibitory rTMS). Whereas excitatory rTMS was associated with statistically reliable effects for improving executive functioning, inhibitory rTMS was associated with statistically reliable effects for improving episodic memory and visual perception. However, the magnitude of these effects was small and no other significant effects were observed. Though future studies are still needed, our findings suggest that offline forms of rTMS may have limited utility in affecting cognitive functioning when applied to the DLPFC in healthy adults, irrespective of cognitive domain or stimulation type.

Recent research has shown complementary engagement of the hippocampus and medial prefrontal cortex (mPFC) in encoding and retrieving associations based on pre-existing or experimentally-induced schemas, such that the latter supports schema-congruent information whereas the former is more engaged for incongruent or novel associations. Here, we attempted to explore some of the boundary conditions in the relative involvement of those structures in short-term memory for visual associations. The current literature is based primarily on intentional evaluation of schema-target congruence and on study-test paradigms with relatively long delays between learning and retrieval. We used a continuous recognition paradigm to investigate hippocampal and mPFC activation to first and second presentations of scene-object pairs as a function of semantic congruence between the elements (e.g., beach-seashell versus schoolyard-lamp). All items were identical at first and second presentation and the context scene, which was presented 500 ms prior to the appearance of the target object, was incidental to the task which required a recognition response to the central target only. Very short lags 2–8 intervening stimuli occurred between presentations. Encoding the targets with congruent contexts was associated with increased activation in visual cortical regions at initial presentation and faster response time at repetition, but we did not find enhanced activation in mPFC relative to incongruent stimuli at either presentation. We did observe enhanced activation in the right anterior hippocampus, as well as regions in visual and lateral temporal and frontal cortical regions, for the repetition of incongruent scene-object pairs. This pattern demonstrates rapid and incidental effects of schema processing in hippocampal, but not mPFC, engagement during continuous recognition.

With population aging and a projected exponential expansion of persons diagnosed with Alzheimer's disease (AD), the development of treatment and prevention programs has become a fervent area of research and discovery. A growing body of evidence suggests that music exposure can enhance memory and emotional function in persons with AD. However, there is a paucity of research that aims to identify specific underlying neural mechanisms associated with music's beneficial effects in this particular population. As such, this paper reviews existing anecdotal and empirical evidence related to the enhancing effects of music exposure on cognitive function and further provides a discussion on the potential underlying mechanisms that may explain music's beneficial effect. Specifically, this paper will outline the potential role of the dopaminergic system, the autonomic nervous system, and the default network in explaining how music may enhance memory function in persons with AD.

Background and objectives It is posited that the difficulty discarding in hoarding disorder (HD) is maintained by a process of negative reinforcement that occurs through avoidance of difficult emotions. Findings regarding the association between emotional experiences and hoarding symptoms have been inconsistent. This study examined relationships between hoarding severity and emotional components of HD using a virtual reality (VR) paradigm. Methods State and trait experiential avoidance (EA), emotional reactivity, and intensity were measured in an HD group (n = 36) and nonhoarding group (n = 40). Both groups underwent a negative or neutral mood induction, followed by a VR acquisition and discarding task. Results The HD group showed higher overall acquisition and greater increases in negative affect following the imagined discarding task than the nonhoarding group, but no differences in discarding patterns. There were no significant correlations between negative affect and acquiring/discarding patterns; nor were there differences related to emotional intensity during mood inductions. Limitations Specificity is limited due to the lack of a clinical comparison group. Conclusions EA may be more important in predicting symptoms than emotional intensity. Implications for cognitive-behavioral models of HD are discussed.

Introduction Working-memory (WM) is a core cognitive deficit among individuals with Schizophrenia Spectrum Disorders (SSD). However, the underlying cognitive mechanisms of this deficit are less known. This study applies a modified version of the Corsi Block Test to investigate the role of proactive interference in visuospatial WM (VSWM) impairment in SSD. Methods Healthy and SSD participants completed a modified version of the Corsi Block Test involving both high (typical ascending set size from 4 to 7 items) and low (descending set size from 7 to 4 items) proactive interference conditions. Results The results confirmed that the SSD group performed worse overall relative to a healthy comparison group. More importantly, the SSD group demonstrated greater VSWM scores under low (Descending) versus high (Ascending) proactive interference; this pattern is opposite to that of healthy participants. Conclusions This differential pattern of performance supports that proactive interference associated with the traditional administration format contributes to VSWM impairment in SSD. Further research investigating associated neurocognitive mechanisms and the contribution of proactive interference across other domains of cognition in SSD is warranted.

Pedophilia is a principal motivator of child molestation, incurring great emotional and financial burdens on victims and society. Even among pedophiles who never commit any offense,the condition requires lifelong suppression and control. Previous comparison using voxel-based morphometry (VBM)of MR images from a large sample of pedophiles and controls revealed group differences in white matter. The present study therefore sought to verify and characterize white matter involvement using diffusion tensor imaging (DTI), which better captures the microstructure of white matter than does VBM. Pedophilics ex offenders (n=24) were compared with healthy, age-matched controls with no criminal record and no indication of pedophilia (n=32). White matter microstructure was analyzed with Tract-Based Spatial Statistics, and the trajectories of implicated fiber bundles were identified by probabilistic tractography. Groups showed significant, highly focused differences in DTI parameters which related to participants’ genital responses to sexual depictions of children, but not to measures of psychopathy or to childhood histories of physical abuse, sexual abuse, or neglect. Some previously reported gray matter differences were suggested under highly liberal statistical conditions (p(uncorrected)

Background. In the chronic stages of moderate-severe traumatic brain injury (TBI), progressive hippocampal volume loss—continuing well after acute neurological insults have resolved—has now been well documented. Previous research in other populations suggests that elevated anxiety symptoms are associated with compromise to the medial temporal lobes. Objective. To examine whether higher anxiety symptoms predict greater hippocampal volume loss in moderate-severe TBI. Methods. We conducted an analysis of prospectively collected, longitudinal behavioral and magnetic resonance imaging (MRI) data from 5 to 12 to 30 months post-injury. Eighty participants were included in the study, with anxiety symptom and MRI data collected at a minimum of 2 time points. Correlational and bivariate latent difference score (with imputation) analyses were used to examine the relationship of Beck Anxiety Inventory scores with hippocampal volume loss, while controlling for depressive symptoms and total brain volume. Results. Analyses revealed that higher anxiety symptoms at 5 and at 12 months following moderate-severe TBI predicted significant later volume loss in the right hippocampal complex and the right hippocampal head. Right hippocampal volume and volume change did not predict subsequent anxiety scores or anxiety change scores. Conclusions. These novel findings implicate anxiety symptoms as a possible predictor of progressive hippocampal volume loss in the chronic stages of moderate-severe TBI.

All possible two-subtest combinations of the core Wechsler Adult Intelligence Scale–IV (WAIS-IV) subtests were evaluated as possible viable short forms for estimating full-scale IQ (FSIQ). Validity of the dyads was evaluated relative to FSIQ in a large clinical sample ( N = 482) referred for neuropsychological assessment. Sample validity measures included correlations, mean discrepancies, and levels of agreement between dyad estimates and FSIQ scores. In addition, reliability and validity coefficients were derived from WAIS-IV standardization data. The Coding + Information dyad had the strongest combination of reliability and validity data. However, several other dyads yielded comparable psychometric performance, albeit with some variability in their particular strengths. We also observed heterogeneity between validity coefficients from the clinical and standardization-based estimates for several dyads. Thus, readers are encouraged to also consider the individual psychometric attributes, their clinical or research goals, and client or sample characteristics when selecting among the dyadic short forms.

HIV stigma is a pressing concern for people living with HIV, and particularly when it is perpetuated by health care providers, as it may affect quality of life and access to health care services. The current study describes the development and initial validation of a contextually appropriate HIV stigma scale for health care providers in North America. A ground-up qualitative approach was used to develop the scale, and it was assessed psychometrically with health care trainees across Canada. The measure demonstrates excellent internal consistency reliability and test-retest reliability, as well as convergent and divergent validity. The study supports a tripartite model of HIV stigma consisting of stereotyping, prejudice and discrimination. The scale provides a new tool to assess HIV stigma in health care providers and can be used to inform training, intervention and self-evaluation of stigmatizing attitudes, beliefs and behaviors among providers.

Spatial memory is impaired among persons with schizophrenia (SCZ). However, different strategies may be used to solve most spatial memory and navigation tasks. This study investigated the hypothesis that participants with schizophrenia-spectrum disorders (SSD) would demonstrate differential impairment during acquisition and retrieval of target locations when using a hippocampal-dependent spatial strategy, but not a response strategy, which is more associated with caudate function. Healthy control (CON) and SSD participants were tested using the 4-on-8 virtual maze (4/8VM), a virtual navigation task designed to differentiate between participants' use of spatial and response strategies. Consistent with our predictions, SSD participants demonstrated a differential deficit such that those who navigated using a spatial strategy made more errors and took longer to locate targets. In contrast, SSD participants who spontaneously used a response strategy performed as well as CON participants. The differential pattern of spatial-memory impairment in SSD provides only indirect support for underlying hippocampal dysfunction. These findings emphasize the importance of considering individual strategies when investigating SSD-related memory and navigation performance. Future cognitive intervention protocols may harness SSD participants' intact ability to navigate using a response strategy and/or train the deficient ability to navigate using a spatial strategy to improve navigation and memory abilities in participants with SSD.

In these studies we examined whether dietary n-3 fatty acid (FA) deficiency in adult male rats was associated with effects on performance in the Morris water-maze and with the development of a conditioned place preference to low (0.5 mg/kg) and high (2.0 mg/kg) doses of amphetamine. The male rats used in these studies had been raised for two generations on n-3 deficient diets, which produced an n-6: n-3 FA ratio in brain lipids three times that of animals fed an n-3 adequate diet. Although the two groups did not differ on learning the position of the hidden platform in the Morris water-maze, the n-3 deficient rats did show deficits on a subsequent working memory version of this task, and swam longer distances to reach a visible platform. There were no differences between the groups on the development of a conditioned place preference although, during the initial conditioning cycle, the increase in activity in response to the high dose of amphetamine was apparent only in the n-3 deficient group. These findings provide preliminary support for effects of n-3 FA deficiency on working memory, but not on motivational processes as measured by response to a drug reward.

Introduction Neuroimaging and other studies have changed the common view that pedophilia is a result of childhood sexual abuse and instead is a neurologic phenomenon with prenatal origins. Previous research has identified differences in the structural connectivity of the brain in pedophilia. Aim To identify analogous differences in functional connectivity. Methods Functional magnetic resonance images were recorded from three groups of participants while they were at rest: pedophilic men with a history of sexual offenses against children (n = 37) and two control groups: non-pedophilic men who committed non-sexual offenses (n = 28) and non-pedophilic men with no criminal history (n = 39). Main Outcome Measure Functional magnetic resonance imaging data were subjected to independent component analysis to identify known functional networks of the brain, and groups were compared to identify differences in connectivity with those networks (or “components”). Results The pedophilic group demonstrated wide-ranging increases in functional connectivity with the default mode network compared with controls and regional differences (increases and decreases) with the frontoparietal network. Of these brain regions (total = 23), 20 have been identified by meta-analytic studies to respond to sexually relevant stimuli. Conversely, of the brain areas known to be those that respond to sexual stimuli, nearly all emerged in the present data as significantly different in pedophiles. Conclusion This study confirms the presence of significant differences in the functional connectivity of the brain in pedophilia consistent with previously reported differences in structural connectivity. The connectivity differences detected here and elsewhere are opposite in direction from those associated with anti-sociality, arguing against anti-sociality and for pedophilia as the source of the neuroanatomic differences detected.

We used the remember-know procedure (Tulving, 1985 ) to test the behavioural expression of memory following indirect and direct forms of emotional processing at encoding. Participants (N=32) viewed a series of facial expressions (happy, fearful, angry, and neutral) while performing tasks involving either indirect (gender discrimination) or direct (emotion discrimination) emotion processing. After a delay, participants completed a surprise recognition memory test. Our results revealed that indirect encoding of emotion produced enhanced memory for fearful faces whereas direct encoding of emotion produced enhanced memory for angry faces. In contrast, happy faces were better remembered than neutral faces after both indirect and direct encoding tasks. These findings suggest that fearful and angry faces benefit from a recollective advantage when they are encoded in a way that is consistent with the predictive nature of their threat. We propose that the broad memory advantage for happy faces may reflect a form of cognitive flexibility that is specific to positive emotions.

Investigation of "out-of-body experiences" (OBEs) has implications for understanding both normal bodily-self integration and its vulnerabilities. Beyond reported associations between OBEs and specific brain regions, however, there have been few investigations of neurochemical systems relevant to OBEs. Ketamine, a drug used recreationally to achieve dissociative experiences, provides a real-world paradigm for investigating neurochemical effects. We investigate the strength of the association of OBEs and ketamine use relative to other common drugs of abuse. Self-report data (N=192) from an online survey indicate that both lifetime frequency of ketamine use and OBEs during ketamine intoxication were more strongly related to the frequency of OBEs and related phenomena than other drugs. Moreover, the apparent effects of other drugs could largely be explained by associated ketamine use. The present results, consistent with the role of NMDA receptors in OBEs, should encourage future studies of the role of neurochemical systems in OBEs.

Spatial pattern separation (SPS) and spatial pattern completion (SPC) have played an increasingly important role in computational and rodent literatures as processes underlying associative memory. SPS and SPC are complementary processes, allowing the formation of unique representations and the reconstruction of complete spatial environments based on partial spatial information. We present two novel computerized navigational tasks as human analogs of well-established rat SPS and SPC tasks. Results from these tasks show that human participants are sensitive to increasing SPS and SPC demands. Specifically, memory accuracy decreased with decreasing separation distance between target and foil locations in the SPS task and with decreasing number of distal spatial cues in the SPC task. These tasks set the stage for valuable future directions, including the use of these tasks with imaging and clinical populations.

Objective Enhanced understanding of cognitive deficits, and the neurobiological abnormalities that mediate them, can be achieved through translational research that employs comparable experimental approaches across species. This study employed a multiple-systems framework derived from the rodent literature to investigate visual-spatial memory abilities associated with schizophrenia. Method Using the bin task, a human analog of rodent maze tasks, everyday objects were hidden in visually identical bins. Following a 1-min filled delay, participants with schizophrenia-spectrum disorders (n = 30) and healthy community controls (n = 30) were asked to identify both the object hidden and bin used on the basis of its spatial location. Three dimensions of visual-spatial memory were contrasted: (a) memory for spatial locations versus memory for objects, (b) allocentric (viewpoint independent) versus egocentric (body-centered) spatial representations, and (c) event (working) memory versus reference memory. Results Most pronounced was a differential deficit in memory for spatial locations under allocentric (p = .005, d = -0.77) but not egocentric viewing conditions (p = .298, d = -0.28) in the schizophrenia group relative to healthy controls. Similarly, schizophrenia-related spatial memory deficits were pronounced under demands for event memory (p = .004, d = -0.77) but not reference memory (p = .171, d = -0.33). Conclusions These results support a heuristic of preferential deficits in hippocampal-mediated forms of memory in schizophrenia. Moreover, the task provides a useful paradigm for translational research and the pattern of deficits suggests that persons with schizophrenia may benefit from mnemonic approaches favoring egocentric representations and consistency when interacting with our visual-spatial world.

Previously we reported a three-factor structure for hallucinations accompanying sleep paralysis (SP). These earlier analyses were, however, based on retrospective accounts. In a prospective study, 383 individuals reported individual episodes online providing further evidence for the three-factor structure as well as clearer conceptually meaningful relations among factors than retrospective studies. In addition, reports of individual episodes permitted a more fine-grained analysis of the internal structure of factors to assess predictions based on the hypothesis that a sensed or felt presence (FP) is a core experience affecting other SP hallucinations. Results were generally consistent with this hypothesis. In particular, associations among, and temporal stability of, sensory hallucinations were largely explained by their common association with FP. The findings are consistent with REM initiation of a threat activated vigilance system with pervasive effects on the SP experience and suggest a potential model for the thematic organization of nightmares and dreams more generally.

Nielsen [Nielsen, T. (2007). Felt presence: Paranoid delusion or hallucinatory social imagery? Consciousness and Cognition, 16(4), 975–983.] raises a number of issues and presents several provocative arguments worthy of discussion regarding the experience of the felt presence (FP) during sleep paralysis (SP). We consider these issues beginning with the nature of FP and its relation to affective-motivational systems and provide an alternative to Nielsen’s reduction of FP to a purely spatial hallucination. We then consider implications of the “normal social imagery” model. We can find only one specific empirical hypothesis articulated within this framework and it turns out to be one that we explicitly addressed in our original paper. We also review our position regarding the possible relation of FP during SP to a number of related anomalous experiences and contrast FP to anomalous vestibular-motor (V-M) phenomena. We review our position that the neuromatrix concept, in the light of available evidence, is more appropriately applied to V-M experiences than FP. Finally, we pursue speculations, raised in Nielsen’s commentary, on the wider implications of FP.

Purpose: Strategic and mnemonic abilities of person with schizophrenia (SCZ) were studied using a part-list cuing (PLC) task. In this task, presentation of retrieval cues in the form of a subset of studied words typically impairs recall of the remaining items. This impairment is thought to reflect a disruption of participants’ natural retrieval strategies. Methods: Participants with SCZ and healthy controls (ns=28) studied word lists with three different levels of semantic organization: (a) unrelated, (b) categorized, but presented in a random order, and (c) presented by category. For each type of list, participants recalled words under both free-recall and PLC conditions. Results: Consistent with SCZ-related impairment of strategic retrieval processes, the SCZ group was less disrupted by PLC interference than controls in the unrelated-list condition. Comparison of free recall across lists also indicated a consistent deficit in SCZ despite varying levels of difficulty and retrieval contexts. Nonetheless, the SCZ group demonstrated parallel improvement to the healthy group with increasing list organization. Conclusions: These results provide evidence of deficient retrieval processes in SCZ in a context placing maximal requirements for utilization of self-initiated, effortful, mnemonic strategies. Unlike most extant results demonstrating mnemonic impairment in persons with SCZ, the present results cannot be accounted for by task difficulty; SCZ participants’ recall was less disrupted by PLC than was that of healthy participants. Results also demonstrated that SCZ participants could benefit, in terms of recall and strategy use, from list organization when this structure was explicitly provided at test. D 2006 Elsevier B.V. All rights reserved.

Clinicians frequently use a crossover approach in switching antipsychotics, although historically there has been a lack of data addressing the question of switch strategies. To establish if there is now empiric evidence that may guide clinicians in this regard, a MEDLINE search to April 2004 was carried out to identify published, randomized and controlled trials that have addressed this topic. A total of 404 articles were identified in the search, which resulted in the identification of four reports meeting the criteria. The four studies evaluated switching strategies to one of three atypical antipsychotics: aripiprazole, olanzapine (two reports), and ziprasidone. The switching process itself could be subdivided as follows: discontinuation (abrupt vs. gradual); and, replacement (abrupt vs. gradual). Meta-analyses confirmed a lack of difference in outcome, regardless of approach. While a crossover approach does not appear to increase adverse events, the available empiric evidence does not support its clinical superiority on various outcome measures. The existing data therefore argue against the position that a crossover approach in switching antipsychotics represents a 'safer' means of preventing clinical deterioration during the switch.

Background: Previous work in our laboratory has shown that exposure to ethanol during the brain growth spurt impairs spatial short-term memory in rats on the delayed matching-to-place (DMP) version of the Morris water maze. The objectives of this study were to ascertain whether this impairment could: 1) be prevented by increasing the length of encoding time and 2) be related to hippocampal c-Fos expression. Methods: Using an artificial rearing model, male Long-Evans rats were fed 6.5g/Kg/day of ethanol from postnatal days 6-9, with controls fed an isocaloric amount of maltose dextrin. As adults, rats in each treatment condition were trained and subsequently tested on either the DMP version of the Morris water maze, or on a random platform version (RAN) that incorporated the same performance requirements, but disallowed spatial learning. Brains were processed for c-Fos expression. Results: Ethanol-exposed rats showed longer search trials during training and took longer to learn the DMP task. When the delay between search and recall trials was increased from 60 sec to 120 min, the performance of ethanol-exposed rats was impaired compared with that of controls after a 10 sec, but not after a 45 sec, encoding time. Brain c-Fos expression was increased in hippocampus, prefrontal cortex and visual cortex in rats trained on the DMP compared to the RAN task. Furthermore, in the DMP-trained rats, hippocampal c-Fos expression was lower in ethanol-exposed rats. Conclusions: These results suggest that the short-term memory impairment of ethanol-exposed rats 1) can be improved slightly by an increase in encoding time and 2) is related to a decrease in c-Fos expression in the hippocampus.

Spontaneously hypertensive rats (SHR) were used as an animal model of attention deficit hyperactivity disorder (ADHD). This study investigated whether, in comparison with its progenitor strain, Wistar-Kyoto rats (WKY), SHR would show deficits in spatial short-term memory in the delayed-matching-to-place (DMP) version of the Morris water maze and be more distracted by exposure to a novel stimulus during recall trials. It also addressed whether dietary supplementation with long-chain polyunsaturated fatty acids (LCPUFA) during development would increase brain docosahexaenoic acid (DHA) and improve SHR behavioral performance. Beginning at weaning (21 days), male SHR and WKY were fed either a control or LCPUFA supplemented diet [0.5% arachidonic acid (AA) and 0.9% DHA], and behavioral testing began at 8 weeks. The first three tasks comprised a series of problems, each consisting of an initial search trial and subsequent recall trials. The intertrial interval (ITI) between the search and recall trial was either 60 s or 60 min. Surprisingly, in contrast to SHR, WKY did not appear to use a spatial short-term memory strategy to solve the problem. Notwithstanding, the performance of both strains was affected by the delay, such that they showed longer path lengths at the long compared with the short ITI. There was no effect of dietary supplementation on DMP performance. SHR fed the control diet were less responsive to a novel stimulus introduced on the first recall trial than WKY, and this tended to increase with supplementation. Analysis of brain fatty acid composition indicated that supplementation did increase DHA in the phosphatidylethanolamine fraction in WKY; however, in SHR, there was either no change (phosphatidylethanolamine) or paradoxical decreases (phosphatidylcholine and phosphatidyserine/phosphatidylinositol). Further research is needed to determine whether SHR are an appropriate model for studying a possible relationship between dietary LCPUFA and the behavioral symptoms of ADHD. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 43: 57–69, 2003.

Previous studies from the human, rodent, and computational research have identified the hippocampus as a core structure mediating pattern separation. However, these investigations have generally focused on the role of distinct subregions of the hippocampus. Less well-understood is how the human hippocampus interacts with other brain regions to support pattern separation. The purpose of this study was to identify the functional networks connected to the hippocampus during delayed matching-to-sample pattern separation tasks promoting either spatial or temporal interference. Results revealed that the hippocampus was functionally connected to two distinct networks. The first network was characterized by correlated activation with the hippocampus primarily in bilateral temporal regions. This network was differentially related to spatial and temporal conditions, suggesting hippocampal connectivity to this network is modulated by interference type. A secondary network was characterized by correlations between the left hippocampus and several other sparsely distributed brain regions, including bilateral cerebellum and frontal and temporal cortices. This network was not modulated by interference type, suggesting that it may be a domain-general pattern separation network. We suggest that the hippocampus may play a role in integrating information from these networks to support performance on pattern separation tasks.

Background: There is concern that, in the absence of full-blown fetal alcohol syndrome, binge drinking during pregnancy might produce long-term cognitive deficits in offspring. Spatial working memory might be particularly vulnerable in this regard. This is the first study to address this issue in an animal model of binge exposure during the brain growth spurt using a delayed matching-to-place (DMTP) task in the Morris water maze. Methods: Infant male rats were gastrostomized and reared artificially from postnatal days (PD) 5 to 18. From PD 6 to 9 they were fed either 6.5 g . kg -1 . d -1 ethanol (EtOH) in a binge exposure model (BAC 302 mg/dl) or an isocaloric maltose-dextrin solution (MD). The study included a third suckled control group (SC) that was reared normally. The rats were tested on a series of problems in the DMTP task, first as juveniles (PD 35) and then twice again as adults. Each problem included an initial search trial and a subsequent test trial. The first two phases of testing used delays of either 0 sec or 60 sec between these two trials. The third phase increased this delay to 60 sec and 2 hr. In addition, the rats were tested on a cued task in the water maze. Results: EtOH rats were impaired relative to controls in their ability to relocate the hidden platform on the second trial, which followed the search trial. In Phases 1 and 2, there was no differential effect of ethanol on performance across the 0-sec and 60-sec delay conditions. However, EtOH rats were more affected by the longer 2-hr delay in Phase 3. There were no group differences on the search trial, in swimming speed, or cued-task performance. Conclusions: These findings establish that binge exposure to ethanol during the brain growth spurt results in a long-lasting impairment on the DMTP performance of rats in the water maze.

Spatial memory is impaired among persons with schizophrenia (SCZ). However, different strategies may be used to solve most spatial memory and navigation tasks. This study investigated the hypothesis that participants with schizophrenia-spectrum disorders (SSD) would demonstrate differential impairment during acquisition and retrieval of target locations when using a hippocampal-dependent spatial strategy, but not a response strategy, which is more associated with caudate function. Healthy control (CON) and SSD participants were tested using the 4-on-8 virtual maze (4/8VM), a virtual navigation task designed to differentiate between participants' use of spatial and response strategies. Consistent with our predictions, SSD participants demonstrated a differential deficit such that those who navigated using a spatial strategy made more errors and took longer to locate targets. In contrast, SSD participants who spontaneously used a response strategy performed as well as CON participants. The differential pattern of spatial-memory impairment in SSD provides only indirect support for underlying hippocampal dysfunction. These findings emphasize the importance of considering individual strategies when investigating SSD-related memory and navigation performance. Future cognitive intervention protocols may harness SSD participants' intact ability to navigate using a response strategy and/or train the deficient ability to navigate using a spatial strategy to improve navigation and memory abilities in participants with SSD.