Continuous Performance Test-Identical Pairs Research Articles

Neuroanatomical mapping of inhibitory attention and working memory with functional magnetic resonance imaging in healthy children

The objective is to produce an average brain activation mapping template in healthy children using functional magnetic resonance imaging (fMRI), with specific paradigms for activating inhibitory attention and working memory functions. A nutritional and neuropsychological evaluation was performed on 87 right-handed children. The inclusion criteria were met by 30 children (15 boys and 15 girls) between 9 and 11 years old, who were studied with fMRI in two inhibitory attention tests (Go/No Go), with food cues, a working memory test (Continuous Performance Test Identical Pairs) and measurement of anatomical volumes. These data were subsequently processed with the FSL-v5 program, with a threshold of p < 0.05 (cluster-wise). The brain areas activated were located using a standard Montreal Neurological Institute brain template and the Harvard-Oxford structural cortical atlas. The inhibitory attention tests showed activation frontal areas predominantly on the right, and the cingulate, parietal and occipital areas, with preponderance in occipital areas in the food cues test. In the Continuous Performance Test-Identical Pairs test, activation was obtained predominantly in the occipital, frontal and parietal areas. Brain activity mapping templates are obtained in healthy children with tests for inhibitory attention, food cues and working memory. The activation areas are mostly those reported in the literature. This provides baseline brain activation patterns for studying pathologies related to inhibitory attention, impulsivity and working memory.

Deep Depression Detection with Resting-State and Cognitive-Task EEG.

Depression is a common mental disorder that negatively affects physical health and personal, social and occupational functioning. Currently, accurate and objective diagnosis of depression remains challenging, and electroencephalography (EEG) provides promising clinical practice or home use due to considerable performance and low cost. This work investigates the capabilities of deep neural networks with EEG-based neural patterns from both resting states and cognitive tasks for depression detection. We collect EEG signals from 33 depressed patients and 40 healthy controls using wearable dry electrodes and build Attentive Simple Graph Convolutional network and Transformer neural network for objective depression detection. Four experiment stages, including two resting states and two cognitive tasks, are designed to characterize the alteration of relevant neural patterns in the depressed patients, in terms of decreased energy and impaired performance in sustained attention and response inhibition. The Transformer model achieves an AUC of 0.94 on the Continuous Performance Test-Identical Pairs version (sensitivity: 0.87, specificity: 0.91) and the Stroop Color Word Test (sensitivity: 0.93, specificity: 0.88), and an AUC of 0.89 on the two resting states (sensitivity: 0.85 and 0.87, specificity: 0.88 and 0.90, respectively), indicating the potential of EEG-based neural patterns in identifying depression. These findings provide new insights into the research of depression mechanisms and EEG-based depression biomarkers.

Sustained attention deficits in schizophrenia: Effect of memory load on the Identical Pairs Continuous Performance Test

BackgroundSustained attention and vigilance impairments are well documented in people with schizophrenia (PSZ). The processes implicated in this impairment remain unclear. Here we investigated whether vigilance performance varied as a function of working memory load, and also examined the role of attentional lapsing that might arise from a loss of task set resulting in mind wandering. MethodWe examined Continuous Performance Test Identical Pairs (CPT-IP) data from a cumulative sample of 247 (PSZ) and 238 healthy control (HC) participants collected over a series of studies. ResultsPSZ performed more poorly that HC across conditions with signal/noise discrimination (d′) decreasing with increasing working memory load across both groups However, there was a significant interaction of group and load suggesting that performance of PSZ was more negatively impacted by increasing load. We also found that PSZ has a significantly higher rate of attention lapsing than did HC. DiscussionOur results suggest that difficulties maintaining task set and working memory limitations are implicated in the impairments observed on the Identical Pairs CPT. Difficulties with task set maintenance appear to explain the majority of between-group variance, with a more subtle impact of increasing working memory load.

Sleep fragmentation and working memory in healthy adults.

IntroductionSleep is essential for performing cognitive function in humans. We have hypothesized that sleep fragmentation compared to sleep efficiency may have a negative impact on the working memory.Material and MethodsTwenty-eight healthy adults (18 males and 10 females; mean age 27.8±15.5 years) were enrolled in this study. We measured the total sleep time (TST), sleep efficiency, %stage wakefulness (W), %stage rapid eye movement (REM), %stage N1, %stage N2, %stage N3, wake after sleep onset (WASO), and arousal index using polysomnography. Working memory, executive function, and sustained attention of three domains of cognitive function were evaluated with the number of back task (N-back task), Wisconsin card sorting test (WCST), and continuous performance test-identical pairs (CPT-IP), respectively.ResultsThe percentage of correct answers on the 2-back task was significantly correlated with %stage REM, %stage N1, and %stage N2 (%stage REM: r=0.505, p=0.006; %stage N1: r=-0.637, p<0.001; %stage N2: r=0.670, p<0.001), and multiple regression analysis including the stepwise forward selection method revealed that %stage N2 was the most significant factor (%stage N2: β=0.670, p<0.001). The percentage of correct answers on the 2-back task was also significantly correlated with TST, sleep efficiency, WASO, and arousal index (TST: r=0.492, p=0.008; sleep efficiency: r=0.622, p<0.001; WASO: r=-0.721, p<0.001; arousal index: r=-0.656, p<0.001), and WASO was the significant factor (β=-2.086, p=0.007). The WCST category achievement and CPT-IP d-prime score were correlated with none of the sleep variables.ConclusionIncreased WASO and a decrease in %stage N2 were associated with worse working memory.

Cognitive function and alcohol use disorder: Path analysis for a cross-sectional study in Taiwan

Objective: Alcohol has cognitive impacts on patients with alcohol use disorder (AUD). In this study, we intended to study cognitive impairments in patients with AUD and their potential interrelationships. Methods: We enrolled 60 patients with AUD or alcohol intoxication in Taiwan. The severity of alcohol use was assessed using a copy for severity of alcohol dependence questionnaire (SADQ). Cognitive function was evaluated using Stroop color and word test, continuous performance test-identical pairs, trail making test, visual alternating and divided attention subscales of computerized everyday attention test, visual elevator subscale of test of everyday attention, Benton judgment of line orientation test, spatial perception subscale of visual object perception test, visual motor organization subscale of Loewenstein occupational therapy, thinking operations subscale of Loewenstein occupational therapy cognitive assessment, digit symbol coding subscale of Wechsler adult intelligence scale-third edition, as well as symbol digit modalities test. Moreover, we used a structural equation modeling (SEM) to link age, duration of alcohol use, SADQ, and cognitive impairments. Results: Patients with AUD had significantly impairments of “attention” (p

The effect of the AKT1 gene and cannabis use on cognitive performance in healthy subjects.

Evidence suggests that the AKT1 gene may modulate the degree to which cannabis use induces cognitive alterations in patients with a psychotic disorder. To examine the interplay between AKT1 and cannabis use in terms of the cognitive performance of the general population. Our sample consisted of 389 Spanish university students. Sustained attention was measured via the Continuous Performance Test-Identical Pairs, immediate and delayed verbal memory with the Logical Memory subtest of the Wechsler Memory Scale, and working memory with the Wisconsin Card Sorting Test. Lifetime cannabis use frequency was assessed and individuals were classified as cannabis users or non-users. Two single nucleotide polymorphisms of the AKT1 gene were genotyped and, according to previous studies, each subject was defined as a carrier of two, one or no copies of the haplotype (rs2494732(C)-rs1130233(A)). Multiple linear regressions were conducted to test the effect of the genetic variability and cannabis use (and their interaction) on cognitive performance. An effect of the AKT1 haplotype was found on attention scores: individuals with two copies of the haplotype performed better (β=0.18, p<0.001 (adjusted for false discovery rate)), while neither cannabis nor the AKT1-cannabis interaction was associated with attention. No effect of AKT1, cannabis or the AKT1-cannabis interaction was found on verbal memory or working memory. Our study provides additional evidence that AKT1 modulates cognitive performance. However, in our non-clinical sample, the previously reported interaction between cannabis use and the AKT1 gene was not replicated.

S176. A PRELIMINARY INVESTIGATION OF COMT GENE INVOLVEMENT IN COGNITIVE FLEXIBILITY AND ATTENTION IN SCHIZOPHRENIA SPECTRUM DISORDERS

BackgroundSchizophrenia spectrum disorders (SSD) are often characterised by a plateau or decline in cognitive abilities early in the prodrome. The cause of developmental alteration remains unknown, and investigation of genetic involvement in cognitive function in these disorders may assist the understanding of the underlying neurobiological mechanisms involved. Variation at two single nucleotide polymorphisms (SNPs) of the catechol-O-methyltransferase (COMT) gene have previously shown an influence on COMT protein levels and cognition; rs4680 and rs4818. Here we investigate the influence of the nonsynonymous “Val/Met” SNP rs4680 and a second functional SNP, rs4818, on tasks of cognitive flexibility and attention.MethodsThe sample comprised 48 healthy controls (HC; age = 31.95 ± 12.80; 25 males, 23 females), and 43 with a diagnosis of SSD (age = 41.64 ± 10.36; 26 males, 17 females). Measures of cognitive flexibility and attention included the Wisconsin Card Sorting Test (WCST), Continuous Performance Test-Identical Pairs version (CPT-IP), Trail Making Test (TMT), and the D-KEFS Colour Word Interference Test (CWIT). Due to small cohort sizes, in our preliminary analyses we chose to compare people who should be most severely affected because of inheriting COMT haplotypes associated with poor cognitive functioning (GG rs4818 / GG rs4680: G-G haplotype) to those with haplotypes associated with better cognitive functioning (CC rs4818 / AA rs4680: C-A haplotype). Multivariate analysis of variance factors included COMT haplotype, diagnosis (HC and SSD), and gender, with Bonferroni correction for multiple comparisons; age was included as a covariate. Analyses were also conducted based on a non-functional SNP of the COMT gene; rs165599, as a negative control.ResultsSSD exhibited reduced cognitive performance compared to HC; F(4, 75) = 8.810, p < .001. Investigation of C-A haplotype revealed an interaction with diagnosis on cognitive performance; F(8, 154) = 2.075, p = .041; SSD had reduced performance compared to HC for the WCST, CPT-IP, and TMT in C-A haplotypes (all p < .05). COMT haplotype also interacted with gender on cognitive performance (C-A haplotype; F(8, 154) = 2.315, p = .023, G-G haplotype; F(8, 154) = 2.706, p = .008). Males who were C-A non-carriers and /or G-G haplotype (high COMT activity groups) performed better on CPT-IP (both p < .05) and worse on CWIT (both p < .05) compared to females. Control SNP rs165599 revealed no main effects or significant interactions (all p > .05).DiscussionThe role of the COMT gene in the cognitive abilities of SSD remains contentious as gene expression does not differ from a healthy population. This preliminary analysis revealed an interaction between diagnosis and COMT haplotype, however, this only reached statistical significance for the C-A haplotype, where SSD with C-A haplotype and C-A non-carriers had reduced performance compared to HC on most tasks except TMT. The different effects found across the tasks, which probed various elements of cognitive flexibility and attention, supports a nuanced role of COMT in cognitive function. Further, high COMT activity was beneficial for males on CPT-IP but not CWIT compared to females. Gender interaction remains a significant consideration in studies of the COMT gene, likely involving the catechol-estrogens which are substrates of COMT. As expected there was no significant results with control SNP rs165599, indicating that findings were due to the influence of SNPs rs4680 and rs4818 on COMT activity.

The correlation between lipid level and cognitive function in first-episode schizophrenia patients with positive and negative symptoms

Objective To explore the characteristics of blood lipid level and cognitive impairment in first-episode schizophrenic patients with positive and negative symptoms, and their correlation. Methods Seventy inpatients with first-episode schizophrenia were enrolled in the hospital.Their psychiatric symptoms were assessed by positive and negative syndrome scale (PANSS). They were divided into two groups: positive symptoms group with 42 patients and negative symptoms group with 28 patients.All patients were assessed with the Chinese version of the measurement and treatment research to improve cognition in schizophrenia consensus cognitive battery (MCCB). The differences and characteristics of cognitive function between the two groups were compared.Body mass index (BMI), serum triglyceride, total cholesterol, low density lipoprotein and high density lipoprotein were recorded at admission, and the results were compared between the two groups.The correlation between cognitive assessment scores and metabolic indicators intra groups were analyzed using pearson correlation analysis. Results The scores of trail making test(TMT), brief assessment of cognition in schizophrenia-symbol encoding(BACS), Hopkins verbal learning test, maze and continuous performance test-identical pairs(CPT-IP) in positive group((27.13±6.89), (32.97±13.69), (35.70±7.52), (32.63±4.59), (33.35±11.10)) were higher than those in negative group ((12.90±14.72), (19.90±11.98), (25.80±5.44), (27.50±5.20), (19.89±11.29), all P<0.05). In terms of BMI and lipid metabolism indicators, the total cholesterol and low-density lipoprotein levels in the negative group ((5.03±1.42), (3.04±1.18)) were higher than those in the positive group ((4.18±0.78), (2.45±0.64)), and the difference was statistically significant (P<0.05). In negative group, total cholesterol and low density lipoprotein were negatively correlated with the scores of TMT(r=-0.469, -0.751), BACS(r=-0.517, -0.538) and CPT-IP(r=-0.495, -0.542) in cognitive function(all P<0.05). Conclusion First-episode schizophrenia patients with positive and negative symptoms have similar lesion dimensions in cognitive function, but patients with negative symptoms are more severely impaired.There are differences in lipid metabolism between first-episode schizophrenia patients with positive dominant symptoms and negative dominant symptoms, and the lipid metabolism of first-episode schizophrenia patients with negative dominant symptoms is related to cognitive function. Key words: First-episode schizophrenia; Negative symptom; Positive symptom; Cognitive function; Lipid metabolism

Effects of sleep-disordered breathing and hypertension on cognitive function in elderly adults

ABSTRACTPurpose: The prevalence of sleep-disordered breathing (SDB) increases with aging. SDB is a risk of hypertension, and both might lead to cognitive decline. However, the role of SDB and hypertension on the pathogenesis of age-related cognitive decline remains unclear. We examined the effects of these two diseases on cognitive function in elderly adults.Methods: Fifty-two elderly individuals (mean age, 69.6 ± 4.0 years) free from impairment in daily living activities participated in this study. Apnea/hypopnea index (AHI) and minimum oxygen saturation (SpO2) were assessed using a portable home monitoring device. We evaluated excessive daytime sleepiness with the Epworth sleepiness scale (ESS). Cognitive performance was assessed using the Wisconsin card sorting test (WCST), continuous performance test-Identical pairs (CPT-IP), and N-back task. Hypertension and diabetes mellitus were evaluated via questionnaire and blood pressure value.Results: The WCST category achievement was significantly lower in participants with minimum SpO2 <90% than those with minimum SpO2 ≥90%. The percentage of correct answer on the 0- and 1-back tasks was significantly lower in the hypertensives than normotensives. Minimum SpO2 was correlated with category achievement on the WCST. Multiple regression analysis including age, sex, body mass index, AHI, minimum SpO2, ESS, hypertension, and diabetes mellitus revealed that hypertension was the most significant factor for percentage correct answers on the 0- and 1-back tasks. There were no significant correlations between body mass index, ESS or diabetes mellitus and the parameters of WCST, CPT-IP, or N-back tasks.Conclusion: In elderly adults, nocturnal hypoxia and hypertension had a negative effect on cognitive function.

Meta-analysis of cognitive function in Chinese first-episode schizophrenia: MATRICS Consensus Cognitive Battery (MCCB) profile of impairment

BackgroundCompromised neurocognition is a core feature of schizophrenia. With increasing studies researching cognitive function of Chinese patients with first-episode schizophrenia (FES) using MATRICS Consensus Cognitive Battery (MCCB), it is not...

SA95 - INDEPENDENT GENETIC EVIDENCE LINKS STRIATAL-ENRICHED PROTEIN TYROSINE PHOSPHATASE (STEP) TO HUMAN ATTENTION AND SCHIZOPHRENIA-RELATED TRAITS

Background Genetic association and protein expression findings in humans and observations in animal models, have implicated the STriatal-Enriched protein tyrosine Phosphatase (STEP) in cognitive functioning and schizophrenia. Methods Here, we aimed to confirm the association between common genetic polymorphisms within PTPN5 encoding STEP, and sustained attention performance assessed with the Continuous Performance Test-Identical Pairs (CPT-IP) among healthy young males (n=1814) and individuals diagnosed with Schizophrenia (SZ; n=341) or Bipolar Disorder (BP; n=239). Moreover, self-rated schizotypal traits and subclinical Psychotic Experiences (PEs) were examined in healthy males, as well as symptom dimensions in an extended SZ data set (n=647). Results We observed that rs10766504, previously associated with increased CPT-IP omission errors among healthy females, predicted greater CPT-IP target detectability in both healthy males and SZ/BP patients (p Discussion These findings underscore PTPN5 as a highly promising candidate gene for sustained attention that merits further genetic and functional investigation. This study also suggests that PTPN5 exerts pleiotropic effects on attention performance and behavioral expressions, which have been linked to altered striatum activity.

Cognitive functions in smoking and non-smoking patients with schizophrenia: A systematic review and meta-analysis of comparative studies

The “Self-medication hypothesis” that has been developed to explain the effect of nicotine in improving aspects of cognitive impairment in schizophrenia remains controversial. This systematic review and meta-analysis compared cognitive functions between smoking and non-smoking schizophrenia patients. The PubMed, PsycINFO, EMBASE, Web of Science, and Cochrane Library databases were systematically and independently searched. Basic demographic and clinical characteristics, smoking history and cognitive performance were recorded. Seven of the 11 studies included in the study, had meta-analyzable data. Compared to non-smoking schizophrenia patients, their smoking counterparts showed significant deficits on the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS)-immediate memory (n = 739), the RBANS-total score (n = 739) and the Continuous Performance Test-Identical Pairs (n = 157). Two of the 4 studies without meta-analysable data did not report significant group difference in performance on the Wechsler Digit Span Task and the Beck Cognitive Insight Scale, while the other 2 studies found that non-smokers outperformed than smokers in problem solving and visual learning. In conclusion, this systematic review and meta-analysis found that smoking schizophrenia patients had worse performance in certain cognitive tasks than non-smoking patients, casting doubts on the validity of the “self-medication hypothesis” that needs to be further examined.

The Relationship Between Measures of Impulsivity and Clinical Characteristics of Patients With Alcohol Use Disorder

The current article presents findings on the interaction between impulsivity features and clinical characteristics of patients with alcohol use disorders (AUD). Patients (n = 88), who were completing detoxification program for the symptoms of AUD, were recruited for the study. They completed biographical questionnaire, Penn CravingScale (PACS), self-report screening measure of the symptoms of adult ADHD (ASRS v.1.1) and underwent a series of experimental tasks (Delay Discounting Task (DDT), Stroop Task, Continuous Performance Test-Identical Pairs (CPT-IP), Tower of London (ToL)). Two distinct groups of impulsivity features were identified using clusteranalysis. One group, which was comprised of DDT and ToL measures, described the level of impulsivity during the decision-making process. The second group included Stroop task and CPT-IP measures and expressed the level of response inhibition and interference control. In addition, the model of interaction between measuresof impulsivity and clinical characteristics of patients was developed. The self-report measure of inattention and hyperactivity had significant effect on the level of craving and the duration of remission. No significant relationships were observed between DDT clinical characteristics.&#x0D; Keywords: impulsivity, alcohol use disorder, delay discounting, stroop task, Tower of London, CPT-IP, craving, ASRS

Details of attention and learning change in first-episode schizophrenia

Impaired attention and learning functions are common in schizophrenia. The details of this impairment, and how these change across time, are not well known. We aimed to compare the parameters of well-known attention and learning neuropsychological tests in first-episode schizophrenia (FES) patients and healthy controls in a 2-year follow-up period. The performance of 28-25 FES patients and pairwise matched healthy controls on the Continuous Performance Test-Identical Pairs, the revised Hopkins Verbal Learning Test, and the revised Brief Visuospatial Memory Test was compared at baseline and 2 years later. The attention dysfunction of the FES group was driven by slow reaction time and a comparative failure to identify correct hits. The reaction time was reduced somewhat across time in the patient group. Regarding the learning tasks, both groups increased their number of correct answers across trials. However, at each trial, the patient group exhibited lower scores, with a trend towards better visual learning performance across time. In summary, the FES patients were impaired in most of the parameters of the attention and learning tasks. Across time, modest improvements in reaction time and visual learning were displayed in the FES group. However, this group never caught up with the control group.

The Impact of Medication Anticholinergic Burden on Cognitive Performance in People With Schizophrenia.

BackgroundCognitive deficits are prevalent in people with schizophrenia and associated with functional impairments. In addition to antipsychotics, pharmacotherapy in schizophrenia often includes other psychotropics, and some of these agents possess anticholinergic properties, which may impair cognition. The objective of this study was to explore the association between medication anticholinergic burden and cognition in schizophrenia.MethodsSeven hundred five individuals with schizophrenia completed a neuropsychological battery comprising Judgment of Line Orientation Test, Wechsler Abbreviated Scale of Intelligence Matrix Reasoning, Continuous Performance Test–Identical Pairs Version, and the Brief Assessment of Cognition in Schizophrenia. Cognitive g and 3 cognitive factor scores that include executive function, memory/fluency, and speed of processing/vigilance, which were derived from a previously published analysis, were entered as cognitive variables. Anticholinergic burden was computed using 2 anticholinergic scales: Anticholinergic Burden Scale and Anticholinergic Drug Scale. Duration and severity of illness, antipsychotic dose, smoking status, age, and sex were included as covariates.ResultsAnticholinergic burden was associated with poorer cognitive performance in cognitive g, all 3 cognitive domains and most cognitive tasks in multivariate analyses. The associations were statistically significant, but the effect sizes were small (for Anticholinergic Burden Scale, Cohen f2 = 0.008; for Anticholinergic Drug Scale, Cohen f2 = 0.017).ConclusionsAlthough our results showed a statistically significant association between medications with anticholinergic properties and cognition in people with schizophrenia, the impact is of doubtful or minimal clinical significance.

Benzodiazepine long-term administration is associated with impaired attention/working memory in schizophrenia: results from the national multicentre FACE-SZ data set

The effect of benzodiazepine long-term administration (BLTA) in cognitive functioning of subjects with schizophrenia (SZ) has been partially explored to date. The objective was to assess BLTA-associated cognitive impairment with a comprehensive cognitive battery in a non-selected multicentric/national community-dwelling sample of stabilized SZ subjects. 407 community-dwelling stabilized SZ subjects were consecutively included in the FondaMental Academic Centers of Expertise for Schizophrenia Cohort (FACE-SZ). Patients taking daily benzodiazepine were defined as BLTA+ as all patients examined by the Expert Center were clinically stabilized and under stable dose of treatment for at least 3months. Each patient has been administered a 1-day long comprehensive cognitive battery (including The National Adult Reading Test, the Wechsler Adult Intelligence Scale, the Trail Making Test, the California Verbal Learning Test, the Doors test, and The Continuous Performance Test-Identical Pairs). In the multivariate analyses, results showed that BLTA was associated with impaired attention/working memory (OR 0.60, 95% confidence interval 0.42-0.86; p=0.005) independently of socio-demographic variables and illness characteristics. Verbal and performance current IQ-[respectively, OR 0.98, 95% CI (0.96;0.99), p=0.016 and 0.98, 95% CI(0.97;0.99), p=0.034] but not premorbid IQ-(p>0.05) have been associated with BLTA in a multivariate model including the same confounding variables. BLTA is associated with impaired attention/working memory in schizophrenia. The BLTA benefit/risk ratio should be regularly reevaluated. Alternative pharmacological and non-pharmacological strategies for comorbid anxiety disorders and sleep disorders should be preferred when possible. It seems reasonable to withdraw BLTA before the start of cognitive remediation therapy, as soon as possible, to improve the effectiveness of this therapy. Limits: the delay between the last benzodiazepine intake and testing, as well as the specific class of benzodiazepines (long half-life vs. short half-life), and the number of benzodiazepine daily intakes have not been recorded in the present study. The precise motive for BLTA prescription and sleep disturbances have not been reported, which is a limit for the interpretation of the present results.

Adverse effects of obesity on cognitive functions in individuals at ultra high risk for bipolar disorder: Results from the global mood and brain science initiative.

The burden of illness associated with bipolar disorder (BD) warrants early pre-emption/prevention. Prediction models limited to psychiatric phenomenology have insufficient predictive power. Herein, we aimed to evaluate whether the presence of overweight/obesity is associated with greater cognitive decline in individuals at high risk (HR) or ultra high risk (UHR) for BD. We conducted a retrospective analysis to investigate the moderational role of body mass index (BMI) on measures of cognitive function. Subjects between the ages of 8 and 28 years with a positive family history of BD were compared to age-matched controls with a negative family history of BD. Subjects with at least one biological parent with bipolar I/II disorder were further stratified into UHR or HR status by the presence or absence, respectively, of subthreshold hypomanic, major depressive, attenuated psychotic, and/or attention-deficit/hyperactivity disorder symptoms. A total of 36 individuals at HR for BD, 33 individuals at UHR for BD, and 48 age-matched controls were included in the analysis. Higher BMI was significantly associated with lower performance on measures of processing speed (i.e. Brief Assessment of Cognition in Schizophrenia-symbol coding: r=-.186, P=.047) and attention/vigilance (i.e. Continuous Performance Test-Identical Pairs: r=-.257, P=.006). There were trends for negative correlations between BMI and measures of working memory (i.e. Wechsler Memory Scale-III Spatial Span: r=-0.177, P=.059) and overall cognitive function (i.e. Measurement and Treatment Research to Improve Cognition in Schizophrenia composite score: r=-.157, P=.097). Negative associations between BMI and cognitive performance were significantly stronger in the UHR group than in the HR group, when compared to controls. Individuals at varying degrees of risk for BD exhibit greater cognitive impairment as a function of co-existing overweight/obesity. Prediction models for BD may be substantively informed by including information related to overweight/obesity and, perhaps, other general medical conditions that share pathology with BD. Our findings herein, as well as the salutary effects of bariatric surgery on measures of cognitive function in obese populations, provide the rationale for hypothesizing that mitigating excess weight in individuals at elevated risk for BD may forestall or prevent declaration of illness.

Differential effects of physical activity and sleep duration on cognitive function in young adults

PurposeAlthough exercise and sleep duration habits are associated with cognitive function, their beneficial effects on cognitive function remain unclear. We aimed to examine the effect of sleep duration and daily physical activity on cognitive function, elucidating the neural mechanisms using near-infrared spectroscopy (NIRS). MethodsA total of 23 healthy young adults (age 22.0 ± 2.2 years) participated in this study. Exercise amount was assessed using a uniaxial accelerometer. We evaluated total sleep time (TST) and sleep efficiency by actigraphy. Cognitive function was tested using the N-back task, the Wisconsin Card Sorting Test (WCST), and the Continuous Performance Test–Identical Pairs (CPT-IP), and the cortical oxygenated hemoglobin levels during a word fluency task were measured with NIRS. ResultsExercise amount was significantly correlated with reaction time on 0- and 1-back tasks (r = −0.602, p = 0.002; r = −0.446, p = 0.033, respectively), whereas TST was significantly correlated with % corrects on the 2-back task (r = 0.486, p = 0.019). Multiple regression analysis, including exercise amount, TST, and sleep efficiency, revealed that exercise amount was the most significant factor for reaction time on 0- and 1-back tasks (β = −0.634, p = 0.002; β = −0.454, p = 0.031, respectively), and TST was the most significant factor for % corrects on the 2-back task (β = 0.542, p = 0.014). The parameter measured by WCST and CPT-IP was not significantly correlated with TST or exercise amount. Exercise amount, but not TST, was significantly correlated with the mean area under the NIRS curve in the prefrontal area (r = 0.492, p = 0.017). ConclusionExercise amount and TST had differential effects on working memory and cortical activation in the prefrontal area. Daily physical activity and appropriate sleep duration may play an important role in working memory.

Prioritizing schizophrenia endophenotypes for future genetic studies: An example using data from the COGS-1 family study

Past studies describe numerous endophenotypes associated with schizophrenia (SZ), but many endophenotypes may overlap in information they provide, and few studies have investigated the utility of a multivariate index to improve discrimination between SZ and healthy community comparison subjects (CCS). We investigated 16 endophenotypes from the first phase of the Consortium on the Genetics of Schizophrenia, a large, multi-site family study, to determine whether a subset could distinguish SZ probands and CCS just as well as using all 16.Participants included 345 SZ probands and 517 CCS with a valid measure for at least one endophenotype. We used both logistic regression and random forest models to choose a subset of endophenotypes, adjusting for age, gender, smoking status, site, parent education, and the reading subtest of the Wide Range Achievement Test. As a sensitivity analysis, we re-fit models using multiple imputations to determine the effect of missing values.We identified four important endophenotypes: antisaccade, Continuous Performance Test-Identical Pairs 3-digit version, California Verbal Learning Test, and emotion identification. The logistic regression model that used just these four endophenotypes produced essentially the same results as the model that used all 16 (84% vs. 85% accuracy).While a subset of endophenotypes cannot replace clinical diagnosis nor encompass the complexity of the disease, it can aid in the design of future endophenotypic and genetic studies by reducing study cost and subject burden, simplifying sample enrichment, and improving the statistical power of locating those genetic regions associated with schizophrenia that may be the easiest to identify initially.

Impaired cortical oxygenation is related to mood disturbance resulting from three nights of sleep restriction

Chronic sleep restriction adversely effects cognitive performance and mood, resulting in accidents and economic loss. We examined the effects of three nights of sleep restriction on cortical oxygenation, cognitive performance and mood. We studied 14 young adults. All subjects spent ≥8 h/night in bed prior to the study day (sufficient sleep), followed by <4 h/night in bed for 3 days (insufficient sleep). Oxyhemoglobin (oxyHb) levels were measured with near-infrared spectroscopy during a word fluency task, and subjects underwent a continuous performance test-identical pairs version (CPT-IP) and filled out the Profile of Mood States (POMS) questionnaire. Peak oxyHb levels after the first and third insufficient sleep nights were significantly lower than that after the sufficient sleep night. Sustained reaction time after the first and third insufficient sleep nights was significantly shorter than that after the sufficient sleep night. Correct response on the CPT-IP after the first and third insufficient sleep nights was significantly less than after the sufficient sleep night. POMS vigor scores after the first and third insufficient sleep nights were both significantly lower than that after the sufficient sleep night. Fatigue and total mood disturbance scores of POMS were significantly higher after the third insufficient sleep night than those after the sufficient sleep night. Three nights of sleep restriction reduced the cortical oxygenation response, and might impair cognitive performance and promote mood disturbance.