Gaze strategies during planning in first-episode psychosis

Eye movements were measured during the performance of a computerized Tower of London task to specify the source of planning abnormalities in patients with 1st-episode schizophrenia or schizoaffective disorder. Subjects viewed 2 arrays of colored balls in the upper and lower parts of the screen. They were asked to plan the shortest sequence of moves required to rearrange the balls in the lower screen to match the upper arrangement. Compared with healthy controls, patients made more planning errors, and decision times were longer. However, the patients showed the same gaze biases as controls prior to making a response, indicating that they understood the requirements of the task, approached the task in a strategic manner by identifying the nature of the problem, and used appropriate fixation strategies to plan and elaborate solutions. The patients showed increased duration of long-gaze periods toward both parts of the screen. This suggests that the patients had difficulty in encoding the essential features of the stimulus array. This finding is compatible with slowing of working memory consolidation.     

HIV, Cognition and Women

Although the incidence of HIV in the United States is higher among men compared to women, the global proportion of women versus men who are infected has been approximately 50% since the late 1990s. Women have been under-represented in neuropsychological studies of HIV. A small number of studies have reported a significantly higher prevalence of neurocognitive impairment among HIV+ women compared to HIV− controls regardless of symptom status and with or without an AIDS diagnosis. Impairment was most evident on psychomotor tasks. The risk of neuropsychological impairment was increased among HIV+ women not on antiretroviral therapy. Age and depressive symptoms also increase neurocognitive risk. New neurocognitive studies of ovarian steroid hormones, PTSD and other psychiatric conditions are critical for addressing potential female-specific aspects of HIV-Associated Neurocognitive Disorder. Such studies will also address questions regarding involvement of the hippocampus and verbal memory, which may be of particular significance among HIV+ women.

Neuroanatomical correlates of intelligence

With the advancement of image acquisition and analysis methods in recent decades, unique opportunities have emerged to study the neuroanatomical correlates of intelligence. Traditional approaches examining global measures have been complemented by insights from more regional analyses based on pre-defined areas. Newer state-of-the-art approaches have further enhanced our ability to localize the presence of correlations between cerebral characteristics and intelligence with high anatomic precision. These in vivo assessments have confirmed mainly positive correlations, suggesting that optimally increased brain regions are associated with better cognitive performance. Findings further suggest that the models proposed to explain the anatomical substrates of intelligence should address contributions from not only (pre)frontal regions, but also widely distributed networks throughout the whole brain.