Table 1.

Percent damage to amygdala and orbital prefrontal cortex in the four operated subjects

CaseAmygdalaOrbital prefrontal
HemispherePercent damageHemispherePercent damage
Op1L (first)42.9R (second)65.5
Op2L (second)34.9R (first)73.3
Op3R (first)95.3L (second)57.1
Op4R (second)28.4L (first)41.1
  • The hemisphere in which each lesion was placed (left, L; right, R) and the order in which the surgeries were conducted are indicated. For example, case Op1 received a neurotoxic amygdala lesion in the left hemisphere before beginning behavioral testing and a lesion of the orbital prefrontal cortex in the right hemisphere, with forebrain commissurotomy in the same surgery, to complete the disconnection. See Figure 1 for a schematic of the behavioral testing sequence.