Autonomic Arousal and Decision Making in Huntington's

Stout, Julie

Abstract

In a recent reports using a simulated gambling task, Bechara, Damasio, and their colleagues propose that in a risky decision making context, people employ somatic guidance to facilitate selection of advantageous response alternatives. As a central piece of evidence, they demonstrate thatsubjects with ventromedial frontal lobe (VMF) damage perform poorly on the gambling task, and that in contrast to healthy subjects, VMF subjects have diminished anticipatory skin conductance responses (SCRs) prior to making disadvantageous selections. These findings have provoked a great deal of interest because they suggest a model for studying how problems in decision making might be linked to failures to integrate affective influences into decision processes. The utility of the gambling task/SCR paradigm in VMF-lesioned subjects is limited because of the rarity of these frontal lobe subjects, the complexity of interpreting gambling task outcomes, and the plethora of cognitive processes that play into a complex decision-making task. The goal of the pilot study proposed in the B/START application is to expand this model of decision making by extending the model to Huntington's disease (HD). HD affects subcortical structures which, in turn, alter functioning of the VMF circuit. Similar to subjects with VMF damage, HD is associated with problems in daily life associated with poor decision making. HD is also associated with deficits in gambling task performance. The proposed study will determine whether gambling task performance is linked to SCRs in HD. The study will provide essential data, such as effect sizes, for designing a more extensive study of the interplay between psychophysiological, neurobehavioral, and cognitive processes in decision making. Improved understanding of the interplay between emotion and cognition is important given evidence of risky behaviors and deficits in judgement in a variety of psychopathological and neurological conditions.