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changes in the reported experience of valence in normal
individuals (Greenwald et al., 1989).
Further, those patient studies that have examined
psychophysiological indices of arousal in response to
emotional stimuli have typically used perceptual stimuli
(i.e., affective scenes) which must be accurately
"interpreted" in order to induce emotion. Patients with RHD
are known to have an array of visuoperceptual and
hemispatial attentional scanning difficulties which can
potentially interfere with their interpretation of such
stimuli. Consequently, findings that RHD patients are
autonomically hypoaroused in response to emotional scenes
may, in part, be secondary to difficulties in interpreting
these stimuli.
To avoid such confounding, the present study used "in
vivo" situations to elicit negative and positive emotions
among focal lesion patients. An anticipatory anxiety
paradigm adopted from Reiman et al. (1989) was used to
induce negative emotion (i.e., anxiety). In this paradigm,
subjects are told that they would sometimes receive a mild
shock. Findings with normals reveal changes in autonomic
arousal during the period that the subject is awaiting shock
in conjunction with self reports of increased levels of
anxiety (as measured by the State-Trait Anxiety Inventory).
An anticipatory reward paradigm was used to induce positive
emotion. Here, subjects were told that they would sometimes