Deficits in visual working-memory capacity and general cognition in African Americans with psychosis

Cocktail-party listening and cognitive abilities show strong pleiotropy

Introduction

The cocktail-party problem refers to the difficulty listeners face when trying to attend to relevant sounds that are mixed with irrelevant ones. Previous studies have shown that solving these problems relies on perceptual as well as cognitive processes. Previously, we showed that speech-reception thresholds (SRTs) on a cocktail-party listening task were influenced by genetic factors. Here, we estimated the degree to which these genetic factors overlapped with those influencing cognitive abilities.

Methods

We measured SRTs and hearing thresholds (HTs) in 493 listeners, who ranged in age from 18 to 91 years old. The same individuals completed a cognitive test battery comprising 18 measures of various cognitive domains. Individuals belonged to large extended pedigrees, which allowed us to use variance component models to estimate the narrow-sense heritability of each trait, followed by phenotypic and genetic correlations between pairs of traits.

Results

All traits were heritable. The phenotypic and genetic correlations between SRTs and HTs were modest, and only the phenotypic correlation was significant. By contrast, all genetic SRT-cognition correlations were strong and significantly different from 0. For some of these genetic correlations, the hypothesis of complete pleiotropy could not be rejected.

Discussion

Overall, the results suggest that there was substantial genetic overlap between SRTs and a wide range of cognitive abilities, including abilities without a major auditory or verbal component. The findings highlight the important, yet sometimes overlooked, contribution of higher-order processes to solving the cocktail-party problem, raising an important caveat for future studies aiming to identify specific genetic factors that influence cocktail-party listening.

Prevalence of COVID 19 Positive Cases Presenting to a Psychiatric Emergency Room

To explore the prevalence of SARS-CoV2 infection in the psychiatric emergency room setting. A Cross-sectional retrospective chart review was used to determine the point-prevalence of SARS-CoV2 infection and the characteristics of those infected. Of the patients tested for SARS-CoV2, 23/1057 (2.2%) were positive. Most of these patients were homeless (living on the street) or came from congregate living settings. The high percentage of SARS-CoV2 positive psychiatric patients coming from congregate living settings stresses the importance of asymptomatic screening in this vulnerable population.

Cognitive impairment from early to middle adulthood in patients with affective and nonaffective psychotic disorders

BACKGROUND

Cognitive impairment is a core feature of psychotic disorders, but the profile of impairment across adulthood, particularly in African-American populations, remains unclear.

METHODS

Using cross-sectional data from a case-control study of African-American adults with affective (n = 59) and nonaffective (n = 68) psychotic disorders, we examined cognitive functioning between early and middle adulthood (ages 20-60) on measures of general cognitive ability, language, abstract reasoning, processing speed, executive function, verbal memory, and working memory.

RESULTS

Both affective and nonaffective psychosis patients showed substantial and widespread cognitive impairments. However, comparison of cognitive functioning between controls and psychosis groups throughout early (ages 20-40) and middle (ages 40-60) adulthood also revealed age-associated group differences. During early adulthood, the nonaffective psychosis group showed increasing impairments with age on measures of general cognitive ability and executive function, while the affective psychosis group showed increasing impairment on a measure of language ability. Impairments on other cognitive measures remained mostly stable, although decreasing impairments on measures of processing speed, memory and working memory were also observed.

CONCLUSIONS

These findings suggest similarities, but also differences in the profile of cognitive dysfunction in adults with affective and nonaffective psychotic disorders. Both affective and nonaffective patients showed substantial and relatively stable impairments across adulthood. The nonaffective group also showed increasing impairments with age in general and executive functions, and the affective group showed an increasing impairment in verbal functions, possibly suggesting different underlying etiopathogenic mechanisms.

Clinical correlates of subsyndromal depression in African American individuals with psychosis: The relationship with positive symptoms and comorbid substance dependence

Patients with psychosis exhibit subsyndromal depressive symptoms during the course of illness and yet the clinical correlates of these symptoms remain under-investigated. We aimed to investigate the clinical correlates of subsyndromal depression in psychosis including the extent to which they mediate commonly observed comorbid substance dependence. We developed a model of depression in a non-clinical sample recruited via Amazon's Mechanical Turk (N = 266), and confirmed that model in a locally recruited African-American clinical sample comprising psychotic and non-psychotic individuals (N = 256). Using scores from this model we tested: the strength of relationships between depressive symptomatology and positive, negative and disorganized symptoms in a range of psychotic disorders; whether depressive symptoms were higher in individuals with affective psychoses versus schizophrenia; and if depressive symptomatology mediated the relationship between psychosis and substance dependence. Subsyndromal depressive symptomatology was significantly higher in individuals with psychosis than without psychosis, but did not significantly differ between affective and non-affective psychotic groups. Depressive symptomatology was significantly related to positive (but not negative or disorganized) psychotic symptoms, and mediated the relationship between psychosis and substance dependence. The present study underlines the importance of assessing subsyndromal depression in patients with psychosis, and generates a number of testable predictions for future work. In particular, the examination of the relationships between comorbid psychopathology, namely depression and substance abuse, may improve insight into the neurobiology of psychosis.

Two good reasons to say 'change!' - ensemble representations as well as item representations impact standard measures of VWM capacity

Visual working memory (VWM) is a central bottleneck in human information processing. Its capacity is most often measured in terms of how many individual-item representations VWM can hold (k). In the standard task employed to estimate k, an array of highly discriminable colour patches is maintained and, after a short retention interval, compared to a test display (change detection). Recent research has shown that with more complex, structured displays, change-detection performance is, in addition to individual-item representations, supported by ensemble representations formed as a result of spatial subgroupings. Here, by asking participants to additionally localize the change, we reveal indication for an influence of ensemble representations even in the very simple, unstructured displays of the colour-patch change-detection task. Critically, pure-item models from which standard formulae of k are derived do not consider ensemble representations and, therefore, potentially overestimate k. To gauge this overestimation, we develop an item-plus-ensemble model of change detection and change localization. Estimates of k from this new model are about 1 item (~30%) lower than the estimates from traditional pure-item models, even if derived from the same data sets.