Cognitive performance and cigarette smoking in first-episode psychosis

The purpose of this study is to describe possible differences in cognitive functioning between smoking and non-smoking patients with first-episode psychosis and to determine whether there is a better cognitive profile associated with smoking. We assessed 61 first-episode psychosis patients with a neuropsychological battery that included computerized measurements of attention, working memory, and executive functioning. Patients were grouped into two categories: non-smokers (0 cigarettes/day; n = 30) and smokers (≥20 cigarettes/day; n = 31). No significant differences were detected in sociodemographic and clinical data between the two groups. For attention tasks, smokers exhibited shorter reaction times in the sustained attention test than non-smokers (P = 0.039) and needed less time to complete the Stroop interference test (P = 0.013). In the working memory task, smokers exhibited shorter reaction times (P = 0.029) and presented a significantly lower percentage of omission (P = 0.002) and commission errors (P = 0.020) than non-smokers. For executive functioning, no differences were detected between groups in performance on the Wisconsin Card Sorting Test. Results indicate that first-episode psychosis patients who are nicotine users have better cognitive functioning in the areas of attention and working memory than patients who are not nicotine users. This study supports the cognitive approach to the self-medication hypothesis, to explain the high rates of cigarette smoking among psychosis patients. These results may be relevant for developing new strategies involving nicotinic receptors for cognitive enhancement in psychosis.     

Chronic depressive symptomatology and CSF amyloid beta and tau levels in mild cognitive impairment

Objectives

To investigate the association between chronic subsyndromal symptoms of depression (SSD), cerebrospinal fluid (CSF) biomarkers, and neuropsychological performance in individuals with mild cognitive impairment (MCI).

Methods

Participants included 238 older adults diagnosed with MCI from the Alzheimer's Disease Neuroimaging Initiative repository with cognitive and CSF amyloid beta (Aβ_1–42), total tau (t‐tau), and phosphorylated tau (p‐tau) data. The Neuropsychiatric Inventory identified individuals with chronic endorsement (SSD group N = 80) or no endorsement (non‐SSD group N = 158) of depressive symptoms across timepoints. CSF biomarker and cognitive performance were evaluated with linear regression models adjusting for age, education, gender, APOE genotype, global cognitive status, and SSD group.

Results

As compared to the non‐SSD group, the SSD group displayed lower CSF Aβ_1–42 levels (β = ?24.293, S.E. = 6.345, P < 0.001). No group differences were observed for CSF t‐tau (P = 0.497) or p‐tau levels (P = 0.392). Lower CSF Aβ_1–42 levels were associated with poorer performance on learning (β = 0.041, S.E. = 0.018, P = 0.021) and memory (β = ?0.012, S.E. = 0.005, P = 0.031) measures, whereas higher CSF t‐tau levels were associated with poorer performance on measures of global cognition (β = 0.022, S.E = 0.008, P = 0.007) and language (β = ?0.010, S.E = 0.004, P = 0.019). SSD was independently associated with diminished global cognition, learning and memory, language, and executive function performance over and above the effects of CSF biomarkers (all P < 0.05).

Conclusions

MCI participants with SSD displayed diminished CSF Aβ_1–42 levels but did not differ from non‐SSD controls in CSF tau levels. Additionally, CSF biomarkers and SSD independently accounted for variance in cognitive performance, suggesting that these factors may uniquely confer cognitive risk in MCI.     

Do complaints of everyday cognitive failures in high schizotypy relate to emotional working memory deficits in the lab?

BackgroundIndividuals high on schizotypy complain of increased cognitive failures in everyday life. However, the neuropsychological performance of this group does not consistently indicate underlying ability deficits. It is possible that current neuropsychological tests lack ecological validity. Given the increased affective reactivity of high schizotypes, they may be more sensitive to emotional content interfering with cognitive ability. This study sought to explore whether an affective n-back working memory task would elicit impaired performance in schizotypy, echoing complaints concerning real world cognition.Methods127 healthy participants completed self-report measures of schizotypy and cognitive failures and an affective n-back working memory task. This task was varied across three levels of load (1- to 3-back) and four types of stimulus emotion (neutral, fearful, happy, sad). Differences between high (n = 39) and low (n = 48) schizotypy groups on performance outcomes of hits and false alarms were examined, with emotion and load as within-groups variables.ResultsAs expected, high schizotypes reported heightened vulnerability to cognitive failures. They also demonstrated a relative working memory impairment for emotional versus neutral stimuli, whereas low schizotypes did not. High schizotypes performed most poorly in response to fearful stimuli. For false alarms, there was an interaction between schizotypy, load, and emotion, such that high schizotypy was associated with deficits in response to fearful stimuli only at higher levels of task difficulty. Inclusion of self-reported cognitive failures did not account for this.ConclusionThese findings suggest that the “gap” between subjective and objective cognition in schizotypy may reflect the heightened emotional demands associated with cognitive functioning in the real world, although other factors also seem to play a role. There is a need to improve the ecological validity of objective assessments, whilst also recognizing that self-reported cognitive failures tap into a range of factors difficult to assess in the lab, including emotion. Cognitive interventions for at-risk individuals will likely be more beneficial if they address emotional processing alongside other aspects of cognition.     

Neuropsychological functioning in early-onset first-episode psychosis: comparison of diagnostic subgroups

The aims of this study were to examine the nature and extent of cognitive impairment in first-episode early-onset psychosis (FE-EOP) soon after their stabilisation and to search for potential differences according to specific diagnostic sub-groups of patients. As part of a Spanish multicentre longitudinal study, 107 FE-EOP patients and 98 healthy controls were assessed on the following cognitive domains: attention, working memory, executive functioning, and verbal learning and memory. Three diagnostic categories were established in the patient sample: schizophrenia (n = 36), bipolar disorder (n = 19), and other psychosis (n = 52). Patients performed significantly worse than controls in all cognitive domains. The three diagnostic sub-groups did not differ in terms of impaired/preserved cognitive functions or degree of impairment. FE-EOP patients show significant cognitive impairment that, during this early phase, seems to be non-specific to differential diagnosis.     

Social cognition according to cognitive impairment in different clinical phenotypes of multiple sclerosis

The objective of this study is to evaluate the relationship between social cognition (SC) and cognitive impairment in persons with multiple sclerosis (PwMS). A prospective study was conducted in 60 PwMS, 30 with relapsing-remitting MS (RRMS), 15 with secondary progressive MS (SPMS) and 15 with primary progressive MS (PPMS), and in healthy subjects (HS). All subjects were assessed by the Bordeaux Social Cognition Evaluation Protocol (PECS-B) (facial emotion recognition, theory of mind, emotional awareness and cognitive and affective alexithymia), by a large neuropsychological battery and by questionnaires (depression and anxiety). 43.3% of PwMS were impaired for at least one SC test. The proportion of PwMS with at least two impaired SC tests was similar in all three phenotypes (20%). Mean scores differed significantly between PwMS and HS only for the Reading the Mind in the Eyes Test, a test of Theory of Mind (ToM). ANOVA analyses showed an effect of phenotype on emotional awareness scores with lower scores in PPMS as compared to RRMS. ToM performance was significantly correlated (r ² = 0.56) with executive functions, working memory and episodic memory scores. SC impairment was found in all phenotypes and was more prominent in cognitively impaired MS patients. Executive functions, and working and episodic memory performance accounts for approximately 50% of ToM performance. Emotional awareness is more impaired in progressive MS.     

Cognitive alterations in patients with non-affective psychotic disorder and their unaffected siblings and parents

Meijer J, Simons CJP, Quee PJ, Verweij K, GROUP Investigators. Cognitive alterations in patients with non‐affective psychotic disorder and their unaffected siblings and parents. Objective: The purpose of this study was to examine a range of cognitive measures as candidate phenotypic liability markers for psychosis in a uniquely large sample of patients with psychosis, their unaffected relatives and control subjects. Method: Patients with non‐affective psychosis (n = 1093), their unaffected siblings (n = 1044), parents (n = 911), and controls (n = 587) completed a comprehensive cognitive test battery. Cognitive functioning was compared using tests of verbal learning and memory, attention/vigilance, working memory, processing speed, reasoning and problem solving, acquired knowledge, and social cognition. Age‐ and gender‐adjusted z‐scores were compared between groups using mixed‐model analyses of covariance. Clinically relevant impairment (?1 and ?2 SD from control mean) was compared between subject groups. Results: Patients performed significantly worse than controls in all cognitive domains (z‐range ?0.26 to ?1.34). Siblings and parents showed alterations for immediate verbal learning, processing speed, reasoning and problem solving, acquired knowledge, and working memory (z‐range ?0.22 to ?0.98). Parents showed additional alterations for social cognition. Prevalence of clinically relevant impairment in relatives ranged from 50% (?1 SD criterion) to 10% (?2 SD criterion). Conclusion: Cognitive functioning is a candidate intermediate phenotype given significant small to large alterations in patients and intermediate alterations in first‐degree relatives.     

NeuroCog FX: Computerized screening of cognitive functions in patients with epilepsy

NeuroCog FX, a computerized neuropsychological screening instrument for serial examinations of patients with epilepsy and other neurological diseases, was developed to fill the gap between unspecific ratings and comprehensive assessments. Eight subtests address attention, working memory, verbal and figural memory, and language. The test duration is less than 30 min. In research contexts, the test can be applied at multiple sites by nonacademic personnel. Normative data were recorded from healthy subjects (N = 244, age range = 16–75 years; retest: N = 44; validation: N = 40) and unselected patients from an epileptology unit (N = 212; retest: N = 94; validation: N = 126). Psychometric analyses confirmed sufficient reliability and concurrent validity, particularly in patients. NeuroCog FX memory and overall performance scores showed “fair” to “good” diagnostic utility with respect to deficits revealed by established tests. NeuroCog FX provides reliable and valid measures of cognitive performance and may be used in clinical and research contexts as a screening instrument.     

Emotion–cognition interactions in schizophrenia

Abstract

Objectives. Negative emotion exerts a considerable influence on cognitive processes. This may have clinical implications in mental illnesses, such as schizophrenia, where negative emotions often prevail. Experimentally this influence can be studied by using olfactory emotion induction. Methods. Fourteen schizophrenia patients and 14 healthy volunteers were investigated with functional magnetic resonance imaging with respect to the neural correlates of emotion–cognition interactions. Emotion was induced by odorants during an n-back working memory task. Results. Similar detrimental effects of negative stimulation on working memory performance were observed in patients and control subjects. Among the neural correlates modulating this interaction a decreased activation emerged in patients in the anterior cingulate and the medial superior frontal cortex and increased activation in the medial orbitofrontal and middle frontal area. Conclusions. During emotion–cognition interaction hypoactivations were found in regions crucial for the monitoring/control of ongoing processes but also for emotion regulation. Decreased activations may reflect failure to adapt to higher task requirements. In contrast, increased activations could be indicative of a greater emotional response and irritation induced by the odour. These patterns may represent the neural correlates of an inefficient control of emotional influences on cognitive processes in patients with schizophrenia.     

The relevance of social anxiety for understanding social functioning and facial emotion recognition in individuals at clinical high-risk for psychosis

Aim

Individuals at clinical high risk (CHR) for psychosis often experience poor social functioning and impaired facial emotion recognition (FER); however, the impact of frequently comorbid symptoms upon these processes is underexplored. In particular, social anxiety is characteristic of this population and also related to poor social functioning and FER biases, such as misinterpreting neutral faces as negative or threatening; however, little is known about how social anxiety relates to these processes in CHR individuals. The present study examined the overlap of social anxiety, social functioning, and FER accuracy and bias.

Method

Participants (CHR N = 62, healthy controls N = 52) completed the self-report Social Interaction Anxiety Scale (SIAS), Penn Emotion Recognition-40 (ER-40) behavioural task, and interviewer-rated Global Functioning Scale-Social (GFS-S). The ER-40 was used to assess both FER accuracy (e.g., overall number of correct responses) and bias (e.g., mislabelling neutral faces as angry).

Results

Consistent with previous research, relative to controls, CHR participants had more social anxiety (d = −1.07), poorer social functioning (d = −1.62), and performed more poorly on the FER task (e.g., d = −.37). Within CHR participants, social anxiety was related to an anger detection bias (r = .28), above and beyond positive symptom severity, which in turn was related to FER accuracy (r = .26) and social functioning (r = −.28).

Conclusion

These findings suggest that ongoing work examining social processes within CHR individuals needs to account for social anxiety and that social anxiety may be a useful preventive intervention target.     

Social Isolation,Loneliness, and Cognitive Performance in Older Adults: Evidence From the ELSI-Brazil Study

BackgroundThe association between social isolation and cognitive performance has been less investigated in low-to-middle-income countries (LMIC) and the presence of depression as a moderator on this association has not been examined. The authors examined the associations of social isolation and perceived loneliness with cognitive performance in the Brazilian Longitudinal Study of Aging.MethodsIn this cross-sectional analysis, social isolation was evaluated by a composite score including marital status, social contact, and social support. The dependent variable was global cognitive performance, which considered memory, verbal fluency, and temporal orientation tests. Linear and logistic regressions were adjusted for sociodemographic and clinical variables. The authors added interaction terms of depressive symptoms with social isolation and loneliness to examine whether depression, measured through the Center for Epidemiologic Studies-Depression Scale, modified these associations.ResultsAmong 6,986 participants (mean age = 62.1 ± 9.2 years), higher levels of social connections were associated with better global cognitive performance (B = 0.02, 95%CI: 0.02; 0.04). Perceived loneliness was associated with worse cognition (B = −0.26, 95%CI = −0.34; −0.18). Interactions of depressive symptoms with social connections scores were found on memory z-score and with loneliness on global and memory z-scores, suggesting a weaker association between social isolation or loneliness and cognition among those with depressive symptoms.ConclusionIn a large sample from an LMIC, social isolation and loneliness were associated with worse cognitive performance. Surprisingly, depressive symptoms decrease the strength of these associations. Future longitudinal studies are important to assess the direction of the association between social isolation and cognitive performance.     

Cognitive performance and smoking in first-episode psychosis: the self-medication hypothesis

The self-medication hypothesis attempts to explain the extraordinary high levels of cigarette smoking in schizophrenia; patients may smoke in an attempt to reduce their cognitive deficits, symptoms, or the side effects of antipsychotics. In a previous report, we detected beneficial performance in attention and working memory in patients with first-episode psychosis who smoked compared to non-smoking patients soon after stabilization. In the present study, we examine differences in the course of those deficits 12 months after the initiation of antipsychotic treatment. We also explore the association between smoking and symptoms and side effects of medication. Neuropsychological assessments were performed at baseline, month 6 and month 12 using a computerized battery that included measures of sustained attention (Continuous Performance Test CPT-O), selective attention (Stroop interference task) and working memory (CPT-XO). Patients met the criterion of fitting in the same smoking category throughout the study: non-smoker (n = 15; 0 cigarettes/day) and smoker (n = 26; >15 cigarettes/day). The non-smoking patients showed significant cognitive improvements, whereas smoking patients lost their superior baseline performance, which was probably obtained through nicotinic stimulation, at the 6- and 12-month assessments due to a static course of deficits. Smokers did not obtain any cognitive benefit after instauration of treatment and worsen their symptoms over the first year. These results suggest that smoking may constitute a marker of a more severe illness. Smoking was not associated with fewer extrapyramidal side effects. Smoking might improve attention and working memory to a similarly modest extent as atypical antipsychotics and could reflect an effort to ameliorate these cognitive dysfunctions previous to treatment instauration.     

Avatar Assistant: Improving Social Skills in Students with an ASD Through a Computer-Based Intervention

This study assessed the efficacy of FaceSay, a computer-based social skills training program for children with Autism Spectrum Disorders (ASD). This randomized controlled study (N = 49) indicates that providing children with low-functioning autism (LFA) and high functioning autism (HFA) opportunities to practice attending to eye gaze, discriminating facial expressions and recognizing faces and emotions in FaceSay’s structured environment with interactive, realistic avatar assistants improved their social skills abilities. The children with LFA demonstrated improvements in two areas of the intervention: emotion recognition and social interactions. The children with HFA demonstrated improvements in all three areas: facial recognition, emotion recognition, and social interactions. These findings, particularly the measured improvements to social interactions in a natural environment, are encouraging.     

The effect of sleep disturbance on social cognition in drug-naïve children with attention deficit and hyperactivity disorder

BackgroundA wide variety of psychiatric conditions are associated with social cognitive deficits. The relationship between social cognition and many factors, especially executive functions (EF), has been examined, but there is no study examining sleep and social cognition in children with attention deficit activity disorder (ADHD). It is important to find new approaches and intervention areas to improve their social cognitive skills. The main hypothesis of our study was that sleep disturbance would predict lower social cognition scores. We hypothesized that sleep disturbances and EF impairment could predict lower social cognitive performance.MethodsEighty-five children aged 7–12 years with drug-naïve ADHD were included in the study. Reading the Mind in the Eyes Test (RMET) and Faux Pas Recognition Test (FPRT) were used for social cognition performance; Stroop test was used for executive function performance. Sleep disturbance was evaluated with Children's Sleep Habits Questionnaire (CSHQ), ADHD severity with Conners Parent Rating Scale (CPRS). Hierarchical multiple regression analyses were performed to determine predictive factors of the FPRT and RMET.ResultsAge, gender, and comorbidity were included at step 1, CPRS-RS score was included at step 2, Stroop test part V score was included at step 3, CSHQ total score and sleep duration were included at step 4. Lower sleep disturbance score on CSHQ was associated with higher social cognition FPRT score (p = 0.014). There was no significant relationship between CSHQ and social cognition RMET score. Lower EF score on Stroop test part V was associated with higher social cognition FPRT score (p = 0.002) and higher social cognition RMET score (p < 0.001).ConclusionThese results showed that sleep disturbance and EF are both associated with social cognitive impairment, sleep particularly with the cognitive component. Identifying sleep problems in children with ADHD may provide helpful information in understanding and treating social cognitive impairments. This study is the first to draw attention to the relationship between sleep and social cognition.     

A longitudinal study of neurocognitive function in individuals at-risk for psychosis

IntroductionClinically defined prodromal diagnostic criteria identify at-risk individuals with a 35–40% likelihood of developing a psychotic disorder within a year. The time course and predictive value of cognitive deficits in the development of psychosis has not been established.MethodsA comprehensive neurocognitive battery and clinical assessments were administered to 37 subjects meeting Criteria of Prodromal States (COPS) criteria for being at risk for psychosis, and two comparison groups: 59 first episode and 47 healthy subjects. Subjects were also evaluated at 6-month and 1-year follow-up periods. Primary analyses used a neurocognitive composite score derived from individual neurocognitive measures, including measures of vigilance, verbal memory, working memory, and processing speed.ResultsAt-risk subjects performed more poorly than healthy subjects (t = 2.93, P = 0.01), but better than first episode subjects (t = 4.72, p < 0.0001). At-risk subjects were particularly impaired on measures of vigilance and processing speed. Cognitive composite scores were significantly lower in at-risk subjects who progressed to psychosis (N = 11; z = − 1.2), while those at-risk subjects who did not progress to psychosis (N = 17) performed better (z = − 0.5), and not significantly different from controls. Poor CPT performance combined with better WAIS-R digit symbol performance predicted progression to psychosis. Severity of neurocognitive deficits was not related to duration of prodrome or to time to development of psychosis and neurocognitive function improved in all subjects except those who progressed to psychosis.ConclusionNeurocognitive impairment emerges early in the course of psychotic illness. Performance on tests of neurocognition may prove to be an early risk predictor for subsequent development of psychotic disorders.     

Emotion Perception in Music in High-Functioning Adolescents With Autism Spectrum Disorders

Individuals with Autism Spectrum Disorders (ASD) succeed at a range of musical tasks. The ability to recognize musical emotion as belonging to one of four categories (happy, sad, scared or peaceful) was assessed in high-functioning adolescents with ASD (N = 26) and adolescents with typical development (TD, N = 26) with comparable performance IQ, auditory working memory, and musical training and experience. When verbal IQ was controlled for, there was no significant effect of diagnostic group. Adolescents with ASD rated the intensity of the emotions similarly to adolescents with TD and reported greater confidence in their responses when they had correctly (vs. incorrectly) recognized the emotions. These findings are reviewed within the context of the amygdala theory of autism.     

Reproducibility of brain‐cognition relationships using three cortical surface‐based protocols: An exhaustive analysis based on cortical thickness

People differ in their cognitive functioning. This variability has been exhaustively examined at the behavioral, neural and genetic level to uncover the mechanisms by which some individuals are more cognitively efficient than others. Studies investigating the neural underpinnings of interindividual differences in cognition aim to establish a reliable nexus between functional/structural properties of a given brain network and higher order cognitive performance. However, these studies have produced inconsistent results, which might be partly attributed to methodological variations. In the current study, 82 healthy young participants underwent MRI scanning and completed a comprehensive cognitive battery including measurements of fluid, crystallized, and spatial intelligence, along with working memory capacity/executive updating, controlled attention, and processing speed. The cognitive scores were obtained by confirmatory factor analyses. T₁‐weighted images were processed using three different surface‐based morphometry (SBM) pipelines, varying in their degree of user intervention, for obtaining measures of cortical thickness (CT) across the brain surface. Distribution and variability of CT and CT‐cognition relationships were systematically compared across pipelines and between two cognitively/demographically matched samples to overcome potential sources of variability affecting the reproducibility of findings. We demonstrated that estimation of CT was not consistent across methods. In addition, among SBM methods, there was considerable variation in the spatial pattern of CT‐cognition relationships. Finally, within each SBM method, results did not replicate in matched subsamples. Hum Brain Mapp 36:3227–3245, 2015. © 2015 Wiley Periodicals, Inc.     

Repetitive Transcranial Magnetic Stimulation (rTMS) Improves Facial Affect Recognition in Schizophrenia

ObjectiveFacial affect recognition, a basic building block of social cognition, is often impaired in schizophrenia. Poor facial affect recognition is closely related to poor functional outcome; however, neither social cognitive impairments nor functional outcome are sufficiently improved by antipsychotic drug treatment alone. Adjunctive repetitive transcranial magnetic stimulation (rTMS) has been shown to enhance cognitive functioning in both healthy individuals and in people with neuropsychiatric disorders and to ameliorate clinical symptoms in psychiatric disorders, but its effects on social cognitive impairments in schizophrenia have not yet been studied. Therefore, we evaluated the effects of sham-controlled rTMS on facial affect recognition in patients with chronic schizophrenia.MethodInpatients (N = 36) on stable antipsychotic treatment were randomly assigned to double-blind high-frequency (10 Hz) rTMS or sham stimulation for a total of ten sessions over two weeks. In the verum group, each session consisted of 10 000 stimuli (20 trains of 5 s) applied over the left dorsolateral prefrontal cortex at 110% of motor threshold. Facial affect recognition was assessed before (T0) and after (T1) the ten sessions.ResultsFacial affect recognition improved significantly more after rTMS (accuracy change: mean = 8.9%, SD = 6.0%) than after sham stimulation (mean = 1.6%, SD = 3.5; Cohen's d = 1.45). There was no correlation with clinical improvement.ConclusionOur results indicate that prefrontal 10 Hz rTMS stimulation may help to ameliorate impaired facial affect recognition in schizophrenia.     

Multi-networks connectivity at baseline predicts the clinical efficacy of left angular gyrus-navigated rTMS in the spectrum of Alzheimer's disease: A sham-controlled study

Introduction

Neuro-navigated repetitive transcranial magnetic stimulation (rTMS) is effective in alleviating cognitive deficits in Alzheimer's disease (AD). However, the strategy for target determination and the mechanisms for cognitive improvement remain unclear.

Methods

One hundred and thirteen elderly subjects were recruited in this study, including both cross-sectional (n = 79) and longitudinal experiments (the rTMS group: n = 24; the sham group: n = 10). The cross-sectional experiment explored the precise intervention target based on the cortical–hippocampal network. The longitudinal experiment investigated the clinical efficacy of neuro-navigated rTMS treatment over a four-week period and explored its underlying neural mechanism using seed-based and network-based analysis. Finally, we applied connectome-based predictive modeling to predict the rTMS response using these functional features at baseline.

Results

RTMS at a targeted site of the left angular gyrus (MNI: −45, −67, 38) significantly induced cognitive improvement in memory and language function (p < 0.001). The improved cognition correlated with the default mode network (DMN) subsystems. Furthermore, the connectivity patterns of DMN subsystems (r = 0.52, p = 0.01) or large-scale networks (r = 0.85, p = 0.001) at baseline significantly predicted the Δ language cognition after the rTMS treatment. The connectivity patterns of DMN subsystems (r = 0.47, p = 0.019) or large-scale networks (r = 0.80, p = 0.001) at baseline could predict the Δ memory cognition after the rTMS treatment.

Conclusion

These findings suggest that neuro-navigated rTMS targeting the left angular gyrus could improve cognitive function in AD patients. Importantly, dynamic regulation of the intra- and inter-DMN at baseline may represent a potential predictor for favorable rTMS treatment response in patients with cognitive impairment.     

Altered resting-state connectivity in subjects at ultra-high risk for psychosis: an fMRI study

Background  

Individuals at ultra-high risk (UHR) for psychosis have self-disturbances and deficits in social cognition and functioning. Midline default network areas, including the medial prefrontal cortex and posterior cingulate cortex, are implicated in self-referential and social cognitive tasks. Thus, the neural substrates within the default mode network (DMN) have the potential to mediate self-referential and social cognitive information processing in UHR subjects.     

Multivariate patterns of brain-cognition associations relating to vulnerability and clinical outcome in the at-risk mental states for psychosis

Background: Neuropsychological deficits are a core feature of established psychosis and have been previously linked to fronto‐temporo‐limbic brain alterations. Both neurocognitive and neuroanatomical abnormalities characterize clinical at‐risk mental states (ARMS) for psychosis. However, structure–cognition relationships in the ARMS have not been directly explored using multivariate neuroimaging techniques. Methods: Voxel‐based morphometry and partial least squares were employed to study system‐level covariance patterns between whole‐brain morphological data and processing speed, working memory, verbal learning/IQ, and executive functions in 40 ARMS subjects and 30 healthy controls (HC). The detected structure–cognition covariance patterns were tested for significance and reliability using non‐parametric permutation and bootstrap resampling. Results: We identified ARMS‐specific covariance patterns that described a generalized association of neurocognitive measures with predominantly prefronto‐temporo‐limbic and subcortical structures as well as the interconnecting white matter. In the conversion group, this generalized profile particularly involved working memory and verbal IQ and was positively correlated with limbic, insular and subcortical volumes as well as negatively related to prefrontal, temporal, parietal, and occipital cortices. Conversely, the neurocognitive profiles in the HC group were confined to working memory, learning and IQ, which were diffusely associated with cortical and subcortical brain regions. Conclusions: These findings suggest that the ARMS and prodromal phase of psychosis are characterized by a convergent mapping from multi‐domain neurocognitive measures to a set of prefronto‐temporo‐limbic and subcortical structures. Furthermore, a neuroanatomical separation between positive and negative brain–cognition correlations may not only point to a biological process determining the clinical risk for disease transition, but also to possible compensatory or dysmaturational neural processes. Hum Brain Mapp 33:2104–2124, 2012. © 2011 Wiley Periodicals, Inc.