right temporal and parietal regions (e.g., Bowers et al.,

1987), whereas studies of emotional mood have implicated the

frontal lobes (e.g., Davidson, 1984).

 Heller (1990) has interpreted the literature in terms

 of type of emotional processing, such that "cold" or

 nonexperienced emotional processing is modulated by the

 right posterior region. In addition, she posited that

 "warm" or experienced positive emotion is processed

 predominantly by the left hemisphere, whereas "warm or

 experienced negative emotion is processed predominantly by

 the right hemisphere. According to Helier, the majority of

 evidence in support of the right hemisphere model of emotion

 comes from studies which have investigated cognitive

 processing of information in brain damaged and normal

 subjects, whereas most evidence in support of the bivalent

 models cf emotion has been derived from lateralization of

 mood states. Heller suggested that there is no reason to

 assume that because a hemisphere is associated with a

 particular mood state, that it must be specific for

 cognitive representations of that emotion.

 In order to distinguish among the ability of the global

and bivalent models nc explain emotional experience, it is

necessary to evoke emccion with both positive/approach and

negative/withdrawal emotions. Because RHD patients have

difficulty interpreting emotional stimuli, including faces

and prosody (e.g., Bowers et al., 1987), it is difficult to