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evoke emotional states in the laboratory. Thus, using an in
vivo situation in which nonverbal emotional stimuli do not
have to be interpreted would be useful in evoking emotion in
RHD patients. Ideally, it is crucial for positive and
negative emotions to be equally arcusing. Unfortunately, it
is difficult to equate in vivo positive and negative
emotional experiences in emotional arousal because highly
arousing negative emotional experience is much easier to
experimentally induce than highly arcusing positive
emotional experience.
It is important to define emotional experience and how
it can be measured. As mentioned above, emotional
experience is defined as a phenomenon which can be
indirectly measured using physiological measures (e.g., HR
and SCR), overt behavior (e.g., facial expression, in this
case measured using CEMG and ZEMG), and verbal report (e.g.,
paper and pencil assessment measures). In normal subjects
these three response systems have usually been found to be
concordant; however, discordant responses have been revealed
in pathological populations (Patrick, Bradley, & Lang,
1991). These discordant results may imply that the three
response systems are mediated by different subsystems. In
brain damaged patients discordance is often observed. For
example, patients with pseudobulbar laughter display overt
behaviors of emotion, but verbally deny feelings associated
with emotion (Heilman, Bowers, & Valenstein, 1993). These