Central Executive Dysfunction and Deferred Prefrontal Processing in Veterans with Gulf War Illness.

Gulf War Illness is associated with toxic exposure to cholinergic disruptive chemicals. The cholinergic system has been shown to mediate the central executive of working memory (WM). The current work proposes that impairment of the cholinergic system in Gulf War Illness patients (GWIPs) leads to behavioral and neural deficits of the central executive of WM. A large sample of GWIPs and matched controls (MCs) underwent functional magnetic resonance imaging during a varied-load working memory task. Compared to MCs, GWIPs showed a greater decline in performance as WM-demand increased. Functional imaging suggested that GWIPs evinced separate processing strategies, deferring prefrontal cortex activity from encoding to retrieval for high demand conditions. Greater activity during high-demand encoding predicted greater WM performance. Behavioral data suggest that WM executive strategies are impaired in GWIPs. Functional data further support this hypothesis and suggest that GWIPs utilize less effective strategies during high-demand WM

Using Priming to Study Social Categorization

Do people spontaneously categorize stereotypically masculine and stereotypically feminine trait and job labels according to gender? The present experiment provided a methodologically stringent test of automatic gender-based categorization using a modification of a semantic priming methodology. Subjects processing goals were manipulated by asking questions about primes that either did or did not require semantic processing. Results provide support for a spontaneous gender-based categorization of trait labels regardless of the processing goals. However, semantic processing goals appear to be necessary for a spontaneous gender-based categorization of job labels