Emotional activation of obese and normal women due to imagery and food content of verbal stimuli in a memory task

Abstract

The aim of this study is to look for correlation between a physiological variable (skin conductance, SCL) and cognitive variables (reaction time, RT and productivity score) obtained in a memory task. Subjects were 17 females, including 7 patients and 10 controls. Patients were recruited among women who went to a clinic for alimentary disorders because of obesity and volunteered for this study; controls were normal women of comparable age without any alimentary problem. Tonic variations of SCL were recorded by a computerized polygraph during the execution of the cognitive task, which consisted of a computerized presentation of frequent, everyday used words evenly divided according to an alimentary/nonalimentary content and to a high/low imagery quality. The acquisition session was followed by an immediate recognition session where subjects were asked to identify the previously presented words among an equal number of similar words not included in the acquisition list. The two session series (acquisition and recognition) were repeated three times to evaluate the learning curve and habituation. This same procedure was separately performed with high imagery alimentary/nonalimentary words and with another list of low imagery alimentary/nonalimentary words. During the recognition tasks, both RT and productivity scores were recorded. A correlation analysis between cognitive and physiological variables was carried out to explore how subjects with different attitudes to food react in cognitive and somatic terms when exposed to verbal stimuli concerning this topic and to neutral verbal stimuli. Results show that obese patients have a different emotional activation in front of these verbal stimuli where both the cognitive activity and the somatic responses are affected by their involvement with the verbal stimuli. On the contrary, the imagery effect does not seem to be influenced by the content and by the idiosyncratic reactions to it of the specific groups of subjects.