Affective Influences on Cognitive Control in High-fear and Phobic Individuals

Résumé du livre

ABSTRACT: High-fear or phobic individuals show abnormal perceptual and psychophysiological responses to fear-evoking stimuli. Recent evidence showsthat such abnormalities may manifest as up-stream impairments in the ability to disengage attentional processes, reflecting an abnormal bias toward processing threat-related stimuli. Recent animal studies suggest that low-level motivational brain structures (e.g., amygdala) may function to take the prefrontal cortex offline during conditions of high emotional activation (e.g., stress), lending behavior to low-level automatic, prepotent processes and impairing high-level executive cognitive control functions. Two recent human studies have corroborated this hypothesis, demonstrating that prefrontal cortex activity during working memory is differentially influenced by emotionally salient stimuli. The present research examines behaviorally the influence of affective stimulation on two prefrontally-mediated cognitive-control processes--working memory (WM) and inhibition of prepotent responses in healthy and high-fear subjects, with the ultimate aim of creating an affective-cognitive probe to study the neuroanatomical bases of fear-related cognitive dysfunction. The task used is a modification of the AX-CPT paradigm that uses affective interfering stimuli of varying valence content pleasant, neutral, unpleasant and clinically-relevant unpleasant. By introducing affective.