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slower reaction times regardless of the hand they used in a
task. They suggested that because patients with RHD have
reduced behavioral evidence of activation, that RHD mediates
the activation process. Specifically, these authors suggest
that the left hemisphere prepares the right extremities for
action, whereas the right hemisphere prepares both sides of
the body for responding. Thus, according to this theory,
the decreased autonomic responding in the RHD group can be
explained by their deficit in global physiological readiness
to respond. The decreased SCRs in most of the LHD group can
not be explained by this theory.
Tranel and Damasio (1994) examined 36 patients with
brain damage who had detailed neuroanatomic evaluations of
their lesions. They found two areas in patients with
unilateral brain damage which affect SCR to positive and
negative emotional slides. One area was the cingulate gyrus
in either the right and left hemisphere. The other area was
the supramarginal gyrus and angular gyrus on the right side
only. In the present study, when subjects were divided into
anterior and posterior lesions, right hemisphere patients
with posterior lesions had smaller SCRs during the shock
condition compared to RHD subjects with anterior lesions.
The opposite trend was found in the LHD group. These trends
are consistent with the findings of Tranel and Damasio
regarding the supramarginal and angular gyri on the right.
The differences in responding in patients with lesions