Correlation between Performance-Based and Interview-Based Cognitive Measurements in Patients with Schizophrenia

OBJECTIVE

The Measurement and Treatment Research to improve Cognition in Schizophrenia Consensus Cognitive Battery (MCCB) is used to measure the cognitive function of patients with schizophrenia. In some situations, interview-based measures such as the Schizophrenia Cognition Rating Scale (SCoRS) may be appropriate. In this study, we analyzed the correlation between performance- and interview-based measurements in patients with schizophrenia.

METHODS

Fifty-six clinically stable patients were recruited. To evaluate cognitive function, we used the MCCB performance-based measure and the SCoRS interview-based measure. Measurements were taken at baseline, and 2 weeks and 3 months later. Spearman correlations were computed between each SCoRS item's interviewer rating and each MCCB score.

RESULTS

The correlation between the MCCB overall T score and the SCoRS global score was the strongest (r=-0.52), while the SCoRS total score and the MCCB Speed of Processing score also correlated (r=-0.48). The SCoRS global score showed statistically significant correlations with all seven MCCB domains and the overall T score.

CONCLUSION

This study reveals correlations between MCCB domains and SCoRS items. Since we find that interview-based measurements are highly correlated with performance-based measurements, we suggest them as a useful cognitive function evaluation tool that can easily be applied in clinical settings.

Associations between dehydroepiandrosterone sulphate (DHEAS) and cognitive function in 5,061 older men and women in the English Longitudinal Study of Ageing

Despite extensive observational and intervention research, the association between concentrations of dehydroepiandrosterone sulfate (DHEAS) and cognition at older ages remains unclear. This study investigated cross-sectional and longitudinal relationships between plasma DHEAS and cognitive function in a large nationally-representative cohort of men and women aged 50 and older. Data were analysed from 5061 participants (mean age 65.1, standard deviation 8.61) who completed memory, verbal fluency and processing speed tests at baseline and two years later. Age, education, marital status, paid employment, depressive symptoms, mobility impairment, coronary heart disease and diabetes were included as covariates, and analyses were stratified by gender. We found positive associations at baseline between DHEAS concentration and aggregate cognition after adjustment for covariates in men (β = 0.049, standard error (s.e.) 0.020, p = 0.015). Longitudinally, DHEAS at baseline predicted cognition two years later in men (β = 0.052, s.e. 0.020, p = 0.010), but not after baseline cognition was taken into account (β = 0.022, s.e. 0.016, p = 0.17), indicating that DHEAS was not associated with rate of cognitive decline. Similar associations were recorded at 6 year follow-up. No significant relationships between DHEAS and cognition were observed among women. We conclude that greater DHEAS concentrations are associated with cognition level at older ages in men, but are unlikely to play a functional role in cognitive decline.

Intellectual functioning and behavior in Dravet syndrome: A systematic review

BACKGROUND

Dravet syndrome (DS) is a developmental and epileptic encephalopathy with onset in the first year of life. At onset, the child displays normal development, but during the second year of life, stagnation/slowing of neurodevelopment is seen. In addition to difficulties with intellectual development, many children display behavioral problems including autistic features, and difficulties with attention and hyperactivity.

AIM

The aim of the present study was to systematically review studies that have focused on the prevalence of cognitive/developmental quotients (DQs) consistent with intellectual disability (ID), deficits in adaptive behavior, autism spectrum disorder (ASD), attention-deficit hyperactivity disorder (ADHD), and behavioral difficulties. A secondary aim was to consider possible factors associated with intellectual and behavioral outcomes in individuals with DS.

METHOD

A systematic review using PubMed and Scopus following the Preferred Reporting Items for Systematic Review (PRISMA) guidelines was conducted on the 24th of September 2019. Study quality was rated by two researchers using the National Institutes of Health (NIH) Quality assessment tools.

RESULT

Twenty-nine studies met inclusion criteria. The pooled prevalence of ID was 86% (range across studies: 50%-100%). The pooled prevalence for ASD was 31%. The mean level of adaptive behavior was more than 2 standard deviations (SDs) below average. The prevalence of behavioral difficulties on standardized instruments ranged between 37% and 100%. The only factor consistently associated with lower cognitive scores was age with older children having significantly lower cognitive scores than younger children. For behavioral difficulties, the most consistent association was with low health-related quality of life (HRQoL) with better HRQoL associated with fewer behavioral difficulties. Study quality was almost universally poor or fair - 15/29 studies were rated 'poor', 13/29 studies were 'fair', and 1 was 'good'.

DISCUSSION

The prevalence of cognitive scores consistent with ID is very high in DS. Many patients also have significant deficits in adaptive behavior highlighting that the majority of patients with DS will meet criteria for ID. The prevalence of ASD would also appear to be higher than the general population but studies show a wide range. Behavioral difficulties are common, but most studies have not used instruments adapted to patients with low intelligence quotient/DQ (IQ/DQ). No study used standardized instruments to assess ADHD. Few studies have used comprehensive statistical methods to evaluate possible factors associated with worse cognitive and behavioral outcome.

CONCLUSION

It should be routine to screen for cognitive and behavioral difficulties for all patients with DS. There is a need for more robust studies regarding intellectual and behavioral disorders in patients with DS. These should be large population-based or multinational studies that employ standardized instruments.

Examining Self-Reported Thought Disorder: Continuous Variation, Convergence with Schizotypy, and Cognitive Correlates

When measured from the perspective of a clinician, the severity of 'objective' thought disorder (TD) has been found to vary continuously between people with and without psychosis-related diagnoses, and has been linked with semantic and executive dysfunctions in people with psychosis. Measures of 'subjective' TD that are derived from a first-person perspective have also been produced, but their relationships with objective TD and cognition are unclear. The aims of the current study were: to determine whether responses on a self-report TD questionnaire correspond with responses to a self-report measure of schizotypal disorganization; and to explore the association between these self-reported subjective TD severities and cognitive performance. Data was collected from a sample of 33 people without psychiatric diagnoses and 38 people diagnosed with schizophrenia or schizoaffective disorder evincing mild symptomatology, and this data was pooled for analysis in accordance with the continuum model. Self-reported TD frequencies were associated with the endorsement of disorganized schizotypal experiences. Moreover, self-reported TD frequencies showed relationships with measures of semantic and executive functioning. Thus, at mild severities, self-reported TD shows continuous variation and is associated with altered cognitive function.

Exploration of the Association Between Obesity and Cognitive Impairment in Chinese Children with Mild or Moderate Obstructive Sleep Apnea-Hypopnea Syndrome

PURPOSE

To explore the association between obesity and cognitive impairment in children with mild or moderate obstructive sleep apnea-hypopnea syndrome (OSAHS).

DESIGN AND METHODS

A total of 71 children with obesity and 71 age- and sex- matched children who were non-obese were included. The Wechsler Intelligence Scale for Children fourth edition (WISC-IV) was adopted to evaluate the cognition of the participating children. Pearson and partial correlation analysis were performed to investigate the relationships between neurocognitive functions and demographic and polysomnography parameters. Two-way Analysis of Variance was performed to evaluate the effect of obesity and apnea-hypopnea index (AHI) on cognitive functions.

RESULTS

Full-scale intelligence quotient (FSIQ, 92.4 ± 12.3 vs. 98.6 ± 13.1; P < 0.01), verbal comprehension index (VCI, 92.8 ± 10.8 vs. 98.7 ± 10.9; P < 0.01), working memory index (WMI, 92.6 ± 11.3 vs. 96.5 ± 11.0; P = 0.04) and perceptual reasoning index (PRI, 93.8 ± 12.1 vs. 99.2 ± 12.5; P < 0.01) were significantly lower in the children with obesity compared with those in the control group. Partial correlation analysis showed that FSIQ were negatively and significantly correlated with body mass index (BMI, r = -0.347, P < 0.01) and AHI (r = -0.304, P < 0.01). Two-way ANOVA revealed that both obesity and AHI had independent effects on FSIQ (both P < 0.05). The interaction between the effect of obesity and AHI on cognitive functions was not significant, indicating that obesity is a risk factor of cognitive impairment independent of AHI.

CONCLUSIONS

Obesity aggravates cognitive impairment in children with mild or moderate OSAHS.

PRACTICE IMPLICATIONS

Children diagnosed with OSAHS and obesity are recommended to control their body weight for the prevention, management and treatment of cognitive impairment.

Orexin and Alzheimer's Disease: A New Perspective

Orexin's role in human cognition has recently been emphasized and emerging evidences indicate its close relationship with Alzheimer's disease (AD). This review aimed to demonstrate recent research on the relationship between orexin and AD. Orexin's role in stress regulation and memory is discussed, with significant findings related to sexual disparities in stress response, with potential clinical implications pertaining to AD pathology. There are controversies regarding the orexin levels in AD patients, but the role of orexin in the trajectory of AD is still emphasized in recent literatures. Orexin is also accentuated in the context of tau pathology, and orexin as a potential therapeutic target for AD is frequently discussed. Future directions with regard to the relationship between orexin and AD are suggested: 1) consideration for AD trajectory in the measurement of orexin levels, 2) the need for objective measure such as polysomnography and actigraphy, 3) the need for close observation of cognitive profiles of orexin-deficient narcolepsy patients, 4) the need for validation studies by neuroimaging 5) the need for taking account sexual disparities in orexinergic activiation, and 6) consideration for orexin's role as a stress regulator. The aforementioned new perspectives could help unravel the relationship between orexin and AD.

Montreal Cognitive Assessment for evaluating the cognitive impairment in patients with schizophrenia: A systematic review

OBJECTIVE

This study aims to systematically review the evidence on the accuracy of the Montreal Cognitive Assessment (MoCA) test for evaluating the presence of cognitive impairment in patients with schizophrenia and to outline the quality and quantity of research evidence available about the accuracy of MoCA in this population.

METHODS

We conducted a systematic literature review, searching four databases from inception until April 2020.

RESULTS

We identified only three cross-sectional studies, two case - control studies, three studies comparing MoCA with Mini-Mental State Examination (MMSE) and four prevalence studies that met the inclusion criteria. Publication period ranged from 2012 to 2020.

CONCLUSIONS

In patients with schizophrenia, the MoCA test provides information about general cognitive functioning disturbances. A lower threshold than the original cut-off of 26 is probably more useful for optimal screening, as it lowers false positive rates and improves diagnostic accuracy. Nonetheless, more studies are necessary in this direction.

Neuropsychological features in patients with severe mental disorders and risk of violence: A prospective multicenter study in Italy

In Severe Mental Disorders (SMDs) the most important cognitive deficits involve the Executive Functions (EFs). In this study we examined the association between EFs and aggressive behaviour in outpatients with SMDs. We included a total of 247 outpatients divided into two groups: 'cases', patients with a history of violence (N=126) and 'non-violent' (N=121). We compared their EFs score and then categorized the participants into four groups (Pathological Non-Violent comparison group; Non-Pathological Non-Violent comparison group; Pathological Violent cases and Non-Pathological Violent cases), based on the scores of a subtest assessing processing speed (i.e., Symbol-coding task) of the Brief Assessment of Cognition in Schizophrenia (BACS). We followed the 4 groups during a 1-year follow-up (FU) monitoring violent behaviour with the Modified Overt Aggression Scale (MOAS). According to the classification based on the BACS-Symbol Coding Task we found no statistically significant differences between subgroups in MOAS scores. We only found that the trend curve for PV was almost consistently over the other group curves in the MOAS 'aggression against people'. Our results suggested a worse performance in the violent compared to non-violent group in EFs. Despite this evidence, the score on the processing speed task was not associated with aggressive behaviour during FU.

Act now before its too late: Copper exposure drives chemo-ecology of predator-prey dynamics of freshwater common spiny loach, Lepidocephalichthys thermalis (Valenciennes, 1846)

Due to the extensive use of copper (Cu) in various commercial products, its existence in aquatic bodies (freshwater and marine) is not unusual. Cu is well known for its effect on the olfactory physiology of fish. However, there are limited studies on the effect of Cu on important ecological functions in fish (predator-prey dynamics) that are primarily influenced by olfaction. In a series of experiments, we studied the effect of Cu exposure on the chemoreceptive behavior of the prey fish, Lepidocephalichthys thermalis. Prey fishes were exposed to an environmentally relevant concentration (5 μg/L) of Cu for 3 h and the anti-predator responses against native (Channa gachua) and alien predatory fish (tilapia) were quantified using an ethological assay. Cu exposed prey fishes did not recognize the native predator and had a lower survival rate than control (unexposed) fishes in predation trials. Cu exposed prey fishes have failed to learn associatively to detect a non-native predator resulting in higher mortality in prey population in direct encounters with tilapia. However, such a lack of predator recognition was found to be short-term and the treated prey fishes recovered anti-predator responses within 72 h. In addition, Cu inactivated the alarm cue which acts as a signal for the presence of predators and ensures associative learning and therefore it was considered to be an 'info-disruptor' in the present study. These outcomes together demonstrate that even at low concentration, Cu influences ecological decisions and survival against predators. Owing to the ubiquitous occurrence of Cu in water bodies, the present investigation will contribute to the knowledge of how environmental stressors alter the crucial ecological decisions of prey individuals in aquatic ecosystems. In addition, we suggest that freshwater reservoirs containing high levels of Cu could be unsuitable for the long-term survival of prey fishes and freshwater biodiversity.

Neuropsychological Alterations in Narcolepsy with Cataplexy and the Expression of Cognitive Deficits

OBJECTIVES

The objective of our study was to assess attention processes and executive function in patients with narcolepsy with cataplexy (NT1). To do so, we compared the results with those of a control group from the general population using an extensive neuropsychological test battery.

METHODS

We studied 28 patients with NT1 and 28 healthy control participants matched for age, gender, and educational level. They all completed questionnaires on sleepiness, anxiety, and depression symptoms. In addition, they underwent neuropsychological tests. The ability to maintain attention was assessed using three computer tasks with different levels of complexity.

RESULTS

Patients had significantly more daytime sleepiness than controls. A significant negative correlation between depression and disease duration was found in NT1 patients. The results of the anxiety questionnaire correlated with the presence of sleep paralysis. There were significant differences in information processing speed subtasks. Patients made significantly more omissions and generally reacted slower and more variably than controls in computerized tasks. As for executive function, patients performed worse in phonologic fluency tasks than controls. However, when the influence of processing speed on fluency tasks was statistically controlled, part of this significant difference disappeared.

CONCLUSIONS

Our results indicate that the negative correlation between depression and disease duration probably reflects progressive adaptation to the functional burden of the disease. Information processing speed plays a fundamental role in the expression of cognitive deficits. We emphasized the need to control the influence of processing speed and sustained attention in the neuropsychological assessment of NT1 patients.

Effects of prenatal exposure to NO2 on children's neurodevelopment: a systematic review and meta-analysis

The neurotoxicity of NO₂ exposure is well-known and potentially causes impaired of neural functions. This review aimed to estimate associations between prenatal NO₂ exposure and neurodevelopment for children. Articles published until May 2019 reported prenatal NO₂ exposure and children's cognition, psychomotor, language, attention, IQ, and behavior function were searched according to all related terms. The main databases we retrieved included PubMed, Web of Science, Embase, and Cochrane Library. Coefficient was extracted, conversed, and synthesized by random effects meta-analysis. Meanwhile, qualitatively describe would be used for some studies which cannot be synthesized quantitatively for lack of quantity or methods inconsistency. Finally, a total of 3848 citations were searched, and only 10 studies were included. We estimated that per 10 μg/m³ increase of NO₂ during pregnancy was associated with a - 0.76 point decrease in global psychomotor (95% CI, - 1.34, - 0.18) and a - 0.62 point decrease in fine psychomotor for children (95% CI, - 1.09, - 0.16). But no significant association found in general cognitive and language. In addition, through the literature review, it seemed that prenatal exposure to NO₂ might cause adverse impacts on children's attention, IQ, and different behaviors, but this requires confirmation from further researches. Our study indicated that prenatal exposure to NO₂ seems to be associated with impaired neural development for children, especially for fine psychomotor. However, further studies are needed for determining the effects of prenatal air pollution exposure on attention, IQ, and behavior.

Neuro-Cognitive Profile of Morning and Evening Chronotypes at Different Times of Day

BACKGROUND

Chronotype is the circadian time preference for sleep-wake timings. However, its impact on cognitive performance is least explored.

OBJECTIVE

The present study investigated the effect of chronotype (morning "M" vs. evening "E") on cognitive measures as a function of time of the day. In addition, the correlation between electroencephalogram (EEG) waves and subjective/objective cognitive measures were investigated.

METHOD

Cognitive status of 28 adult male subjects (15 "M" and 13 "E") was assessed objectively through event-related potential (ERP) by administering visual odd ball paradigm test and subjectively through Montreal Cognitive Assessment questionnaire. In addition, 20 to 30 min of resting EEG was recorded. Recordings were done from 8 to 10 am and from 4 to 6 pm on a single day. Power spectral analysis of EEG for alpha and beta waves at PZ and FZ cortical sites was done after subjecting selected epochs to fast Fourier transformation. Also, latency and amplitude of P300 potential from event-related potential record were measured. Appropriate statistical tests were applied for analysis.

RESULTS

Higher alpha and beta power was observed in "E" at PZ in the evening. "M" showed increased P300 latency and amplitude during evening session for frequent and rare stimuli and vice versa in "E."' Significant negative correlation was seen between latency of rare stimuli and alpha and beta power at FZ site during evening in "E" chronotype only.

CONCLUSION

Result indicates better attention and alertness during evening hours in evening chronotypes and vice versa in morning chronotypes. The findings could be implemented to schedule the mental performance/cognitive load according to individual chronotype.

Finding Suitable Clinical Endpoints for a Potential Treatment of a Rare Genetic Disease: the Case of ARID1B

There is a lack of reliable, repeatable, and non-invasive clinical endpoints when investigating treatments for intellectual disability (ID). The aim of this study is to explore a novel approach towards developing new endpoints for neurodevelopmental disorders, in this case for ARID1B-related ID. In this study, twelve subjects with ARID1B-related ID and twelve age-matched controls were included in this observational case-control study. Subjects performed a battery of non-invasive neurobehavioral and neurophysiological assessments on two study days. Test domains included cognition, executive functioning, and eye tracking. Furthermore, several electrophysiological assessments were performed. Subjects wore a smartwatch (Withings® Steel HR) for 6 days. Tests were systematically assessed regarding tolerability, variability, repeatability, difference with control group, and correlation with traditional endpoints. Animal fluency, adaptive tracking, body sway, and smooth pursuit eye movements were assessed as fit-for-purpose regarding all criteria, while physical activity, heart rate, and sleep parameters show promise as well. The event-related potential waveform of the passive oddball and visual evoked potential tasks showed discriminatory ability, but EEG assessments were perceived as extremely burdensome. This approach successfully identified fit-for-purpose candidate endpoints for ARID1B-related ID and possibly for other neurodevelopmental disorders. Next, results could be replicated in different ID populations or the assessments could be included as exploratory endpoint in interventional trials in ARID1B-related ID.

Controlled sleep deprivation as an experimental medicine model of schizophrenia: An update

In recent years there has been a surge of interest and corresponding accumulation of knowledge about the role of sleep disturbance in schizophrenia. In this review, we provide an update on the current status of experimentally controlled sleep deprivation (SD) as an experimental medicine model of psychosis, and also consider, given the complexity and heterogeneity of schizophrenia, whether this (state) model can be usefully combined with other state or trait model systems to more powerfully model the pathophysiology of psychosis. We present evidence of dose-dependent aberrations that qualitatively resemble positive, negative and cognitive symptoms of schizophrenia as well as deficits in a range of translational biomarkers for schizophrenia, including prepulse inhibition, smooth pursuit and antisaccades, following experimentally controlled SD, relative to standard sleep, in healthy volunteers. Studies examining the combination of SD and schizotypy, a trait model of schizophrenia, revealed only occasional, task-dependent superiority of the combination model, relative to either of the two models alone. Overall, we argue that experimentally controlled SD is a valuable experimental medicine model of schizophrenia to advance our understanding of the pathophysiology of the clinical disorder and discovery of more effective or novel treatments. Future studies are needed to test its utility in combination with other, especially state, model systems of psychosis such as ketamine.

MOG-antibody-associated hypertrophic pachymeningitis

BACKGROUND

The clinical spectrum of myelin oligodendrocyte glycoprotein (MOG)-antibody-associated disease is expanding.

OBJECTIVE

To describe an unusual case of MOG-antibody-associated hypertrophic pachymeningitis (HP).

METHODS

Case study.

RESULTS

A 57-year-old female presented with a generalised seizure on a background of 3 months history of progressive cognitive decline and behavioural changes. Brain Magnetic Resonance Imaging (MRI) revealed widespread pachymeningeal enhancement and hyperintense signal in both hippocampi. Cerebrospinal Fluid (CSF) examination was normal. The patient was found positive for MOG-antibody. She clinically improved with steroids and the MRI abnormalities completely resolved.

CONCLUSIONS

Clinicians might consider testing for MOG-antibody in cases with HP.

Clinical and cognitive correlates of childhood attention-deficit/hyperactivity disorder in first-episode psychosis: A controlled study

The relationship between childhood attention-deficit/hyperactivity disorder (c-ADHD) and psychosis has been understudied. Cognitive dysfunction is a core feature of both disorders, but no previous study has investigated whether first-episode psychosis (FEP) with c-ADHD (FEP-ADHD⁺) presents a different cognitive profile than FEP without c-ADHD (FEP-ADHD^-). One hundred and thirty-three FEP outpatients were screened for c-ADHD through a diagnostic interview and underwent a comprehensive clinical and cognitive assessment with the MATRICS Consensus Cognitive Battery (MCCB). Cognitive differences among FEP groups, and a group of 65 healthy controls (HCs) were analysed by multivariate analysis of covariance. Nearly 25% of FEP fulfilled criteria for c-ADHD. Both FEP groups performed worse than HCs in speed processing, executive function and social cognition, but only the FEP-ADHD⁺group was significantly more impaired than the HC group in attention (F = 4.35; p = 0.04). Only the Trail Making Test A (TMT-A) (F = 6.99; p = 0.01) within the domain of processing speed and the Neuropsychological Assessment Battery (NAB) (F = 6.46; p = 0.01) within the domain of executive function reliably differentiated the two clinical groups. The FEP groups did not differ in the severity of psychopathology, but the FEP-ADHD⁺reported fewer years of education than the FEP-ADHD^- and were more likely to use tobacco and cannabis and to require higher doses of antipsychotics to achieve a clinical response. In conclusion, we found a gradient of severity in cognitive performance between groups, with FEP-ADHD⁺ having the greatest cognitive impairment. Our results suggest that FEP-ADHD⁺ represents a subgroup with a worse prognosis than FEP-ADHD^-.

Psychotic depressive subtype and white mater hyperintensities do not predict cognitive side effects in ECT: A systematic review of pretreatment predictors

BACKGROUND

Most studies regarding cognitive side-effects following ECT for treating depression report transient forms of cognitive disturbances. However, a growing number of studies also report considerable differences among individual patients.

OBJECTIVE

The aim of this systematic review was to identify pretreatment patient characteristics for predicting the risk of developing cognitive side-effects following ECT.

METHODS

Online databases PubMed/Medline, Embase, and PsycINFO were searched for articles published from 2002 through May 2019, using the following relevant search terms: #cognitive deficits AND #Electro Convulsive Therapy. Inclusion and exclusion criteria were applied for full-text inclusion. PRISMA guidelines were used.

RESULTS

Our initial search yielded 2155 publications; 16 studies were included. A total of 16 possible predictive factors were identified. Two factors, psychotic features and white matter hyperintensities, were conclusively found to not predict cognitive side-effects following ECT; the remaining 14 factors were inconclusive.

CONCLUSIONS

There is robust evidence that psychotic features and white matter hyperintensities are not predictive of cognitive side-effects following ECT. None of the other 14 factors examined were predictive, however these levels of evidence were weak and therefore inconclusive. Additional studies focusing primarily on pretreatment patient characteristics for predicting cognitive side-effects following ECT are needed, including demographic, clinical, physiological, neurobiological, and genetic factors. Finally, we provide suggestions for future research.

Amphetamine improves rat 5-choice continuous performance test (5C-CPT) irrespective of concurrent low-dose haloperidol treatment

RATIONALE

Cognitive dysfunction mediates functional impairment in patients with schizophrenia, necessitating the timely development of pro-cognitive therapeutics. An important initial step in this process is to establish what, if any, pro-cognitive agents and associated mechanisms can be identified using cross-species translational paradigms. For example, attentional deficits-a core feature of schizophrenia-can be measured across species using the 5-choice continuous performance test (5C-CPT). The psychostimulant, amphetamine, improves human and rodent 5C-CPT performance.

OBJECTIVE

Here, we tested whether amphetamine would similarly improve 5C-CPT performance in the presence of dopamine D2 receptor blockade, since pro-cognitive treatments in schizophrenia would virtually always be used in conjunction with D2 receptor antagonists.

METHODS

We established the dose-response effects of amphetamine (0, 0.1, 0.3, or 1.0 mg/kg) and haloperidol (0, 3.2, 10, or 32 μg/kg) on 5C-CPT performance in Long Evans rats, and then tested an amphetamine (0.3 mg/kg) × haloperidol (10 μg/kg) interaction; the low dose was chosen because higher doses exerted deleterious non-specific effects on performance.

RESULTS

Amphetamine improved 5C-CPT performance in poorly performing rats by increasing target detection, independent of haloperidol pretreatment.

CONCLUSIONS

The pro-attentional effects of amphetamine were most likely mediated by dopamine release at D1-family receptors, since they persisted in the presence of acute D2 blockade. Alternative explanations for these findings are also discussed, as are their potential implications for future pro-cognitive therapeutics in schizophrenia.

The Effects of Low-Risk Drinking on Neurocognition Among Older Persons Living With HIV as Compared to Those Without HIV

BACKGROUND

Heavy alcohol use negatively impacts neurocognition, but some studies report neurocognitive benefits associated with light drinking among HIV-seronegative (HIV-) older persons, suggesting a nonlinear or an inverted "J-shaped" association of alcohol consumption on neurocognition. Alcohol use is common among people with HIV (PWH); however, the association between recent "low-risk" alcohol consumption and neurocognition among PWH is poorly understood.

METHODS

Participants included 310 PWH and 89 HIV- older (≥50 years) adults who reported alcohol abstinence or "low-risk" drinking, defined per the National Institute on Alcohol Abuse and Alcoholism criteria (i.e., ≥15 drinks/wk or ≥5 drinks/d for men; ≥8 drinks/wk or ≥4 drinks/d for women). Neurocognition was measured using global and domain-specific demographically corrected T-scores. Multiple linear regressions examined the interaction between total drinks in the last 30 days (linear and quadratic terms) and HIV serostatus on neurocognition, covarying for age, sex, lifetime major depressive disorder, lifetime nonalcohol substance use disorders, and lifetime alcohol use disorder.

RESULTS

Total drinks consumed in the last 30 days did not differ by HIV serostatus (p = 0.202). Among HIV- older adults, quadratic effects of total drinks on neurocognition occurred such that optimal neurocognition (i.e., global function, executive function, learning, delayed recall, and motor skills) was detected at intermediate levels of "low-risk" drinking (~20 to 40 drinks), with poorer performance at the lower and higher ranges of "low-risk" consumption. In PWH, total drinks did not exhibit linear or quadratic associations with neurocognition.

CONCLUSIONS

In HIV- "low-risk" drinkers, intermediate levels of recent alcohol use were associated with better neurocognition, consistent with the inverted J-shaped association. The same nonlinear effect of recent alcohol consumption on neurocognition was absent in PWH, indicating there may be no beneficial or deleterious effects of low-risk alcohol consumption on neurocognition among PWH. Future research is warranted to examine associations between alcohol consumption and HIV-related biopsychosocial disadvantages that may supersede the neurocognitive benefits of alcohol.

Efficacy and safety of valproic acid in dementia: A systematic review with meta-analysis

INTRODUCTION

The neuroprotective effect of valproic acid has been observed in the animal models of neurodegeneration, which suggests it as a potential candidate for clinical trials. In this paper, we aimed to systematically analyze the efficacy and safety of valproic acid in the treatment of dementia.

METHODS

We searched the electronic databases PubMed, EMBASE, CINAHL, Cochrane Library and China National Knowledge Infrastructure until March 2020 for the eligible randomized controlled trials, as well as the unpublished and ongoing trials. We pooled the results using a random-effects model.

RESULTS

We included seven studies with 770 randomized patients with dementia, which compared valproic acid with placebo. Indeed, there were no significant differences found in the scores of Mini-mental State Examination, Cohen-Mansfield Agitation Inventory and number of patients with adverse events. Valproic acid is generally well-tolerated in patients with dementia, even in long-term therapy for 24 months.

CONCLUSION

Insufficient evidences are found to support valproic acid in the treatment of dementia for cognitive, psychiatric symptoms or disease-modifying. The anticipations for a success in the trial of valproic acid for dementia in the future look not optimistic based on the available evidence.

Association between cognition and suicidal ideation in patients with major depressive disorder: A longitudinal study

BACKGROUND

Suicidal ideation (SI) is common in patients with major depressive disorder (MDD) and often related to cognitive deficits. Limited longitudinal study has shown that cognitive improvement is associated with reduced SI. However, the comparatively study in Chinese depressed patients is still absent. The objective of this study was to explore the specific cognitive deficits in Chinese MDD with SI and investigate the relationship between changes in cognition and change in SI across antidepressant treatment.

METHODS

Three hundred and five patients with MDD received four weeks of antidepressant treatment. The 17-item Hamilton Depression Rating Scale (HAMD-17) and four domains of the MATRICS Consensus Cognitive Battery (MCCB), including speed of processing, working memory, visual learning and verbal learning were measured at baseline and four-week follow-up.

RESULTS

One hundred and thirty patients (42.6%) expressed suicidal ideation. Suicidal patients performed worse on verbal learning than non-suicidal patients. Change in speed of processing domain was negatively associated with change in suicidal scores over time. Logistic regression analysis showed that reduction of SI was associated with improvement of speed of processing.

LIMITATION

The major limitation was that there was no healthy control group in the current study, which might limit the interpretation of cognitive deficits in depressed patients with SI.

CONCLUSIONS

Our findings suggest that suicidal patients performed worse on verbal learning which can potentially serve as a cognitive biomarker of suicide risk in MDD. Moreover, reduced suicidal ideation was associated with improved speed of processing.

Structured Sequence Learning: Animal Abilities, Cognitive Operations, and Language Evolution

Human language is a salient example of a neurocognitive system that is specialized to process complex dependencies between sensory events distributed in time, yet how this system evolved and specialized remains unclear. Artificial Grammar Learning (AGL) studies have generated a wealth of insights into how human adults and infants process different types of sequencing dependencies of varying complexity. The AGL paradigm has also been adopted to examine the sequence processing abilities of nonhuman animals. We critically evaluate this growing literature in species ranging from mammals (primates and rats) to birds (pigeons, songbirds, and parrots) considering also cross-species comparisons. The findings are contrasted with seminal studies in human infants that motivated the work in nonhuman animals. This synopsis identifies advances in knowledge and where uncertainty remains regarding the various strategies that nonhuman animals can adopt for processing sequencing dependencies. The paucity of evidence in the few species studied to date and the need for follow-up experiments indicate that we do not yet understand the limits of animal sequence processing capacities and thereby the evolutionary pattern. This vibrant, yet still budding, field of research carries substantial promise for advancing knowledge on animal abilities, cognitive substrates, and language evolution.

Pioglitazone alleviates maternal sleep deprivation-induced cognitive deficits in male rat offspring by enhancing microglia-mediated neurogenesis

Maternal sleep disturbance in pregnancy causes cognitive impairments and emotional disorders in offspring. Microglia-mediated inflammatory processes contribute to prenatal stress-induced neurodevelopmental deficits. Peroxisome proliferator-activated receptor gamma (PPARγ) activation underlies the switching of microglial activation phenotypes, which has emerged as a pharmacological target for regulating neuroinflammatory responses in the treatment of neuropsychiatric disorders. Here we investigated the effects of PPARγ-dependent microglial activation on neurogenesis and cognitive behavioral outcomes in male rat offspring exposed to maternal sleep deprivation (MSD) for 72 h from days 18-21 of pregnancy. In the Morris water maze test, male MSD rat offspring needed more time than control offspring to escape to the hidden platform and spent less time in the target quadrant when the hidden platform was removed. In MSD rat offspring, microglial density as determined by immunofluorescence was higher, microglia showed fewer and shorter processes, and neurogenesis in the hippocampus was significantly reduced. Levels of mRNA encoding pro-inflammatory markers IL-6, TNFα, and IL-1β were higher in male MSD offspring, whereas levels of anti-inflammatory markers Arg1, IL-4, and IL-10 were lower, as was PPARγ expression in the hippocampus. PPARγ activation by pioglitazone (30 mg/kg/day, i.p., 7 d) mitigated these negative effects of MSD, rescuing hippocampal neurogenesis and improving cognitive function. The PPARγ inhibitor GW9662 (1 mg/kg/day, i.p., 7 d) eliminated the effects of pioglitazone. Conditioned medium from pioglitazone-treated microglia promoted proliferation and differentiation of neural progenitor cells. These results suggest that MSD-induced deficits in spatial learning and memory can be ameliorated through PPARγ-dependent modulation of microglial phenotypes.

Dataset on sociability, cognitive function, gene and protein expression of molecules involved in social behavior, reward system and synapse function following early-life status epilepticus in Wistar rats

Early-life status epilepticus produces deficit in social interaction and vocalization, enhances anxiety, no cognitive impairment and alters functional connectivity within the hippocampus (CA3-CA1) and between the hippocampus and prefrontal cortex [1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], but the underlying mechanisms remain unknown. This data article contains behavioral and molecular data of the adult male Wistar rats subjected to early life pilocarpine-induced seizures. Animal's behaviors were assessed to social memory and social motivation, working and reference memories and cognitive flexibility. The brain tissues (hypothalamus, hippocampus, amygdala, and striatum) were probed to gene and protein expression of molecules related to social behavior, reward system and synaptic function.