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involving the cingulate gyrus could not be examined in the
present sample because few patients had lesions involving
that area.
Limitations of the Study
There are several limitations of the present study.
First, both normal and brain damaged subjects did not show
the normal orienting and habituation in the
psychophysiological screening. As a consequence, it can not
be said that the RHD patients in this study have a specific
deficit in electrodermal arousal, as measured by SCR.
Tranel and Damasio found that some stroke patients have
deficits in orienting and emotional arousal, whereas others
have deficits in emotional arousal alone. Other
researchers, however, have found patients with RH strokes
show normal orienting, but abnormal emotional arousal
(Meadows and Kaplan, 1994). The orienting procedure used
by Meadows and Kaplan differed from the present study in
that they used much louder tone (100 db), whereas the
present authors used tones of 60 db. This difference in the
intensity of the tones may account for the discrepancy
between the current findings and those revealed by Meadows
and Kaplan.
Second, none of the psychophysiological measures
accurately distinguish the reward from the control
situation. Because this suggests that the reward condition
was problematic, the global and bivalent models could not be