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 the CONS. During the shock trials, however, the RHD and LHD

 group had fewer responses than the CONS, whereas there were

 no group differences during the no-shock trials. Subjects

 demonstrated greater magnitude of responding during the

 shock compared to the no shock condition. Also, there was a

 significantly greater magnitude during block 1, than blocks

 2, 3, and 4. Additionally, the shock tone produced

 significantly greater magnitude of responding when compared

 to the no-shock tone during blocks 1 and 4. Also, during

 shock anticipation the RHD group had significantly smaller

 responses than the CONS, whereas the LHD group did not

 significantly differ from any of the other groups.

 Facial electromyography (EMG). Ipsilateral corrugator

EMG (CEMG), left zygomatic EMG (ZGL), and right zygomatic

EMG (ZGR) were analyzed separately using change from

baseline as the dependent variables. Repeated measures

ANOVAs were employed. Group was the between subject factor

(LHD, LH NCS, RHD, RH NCS). Block (one to four) and

condition (high and low) were the within subject factors.

Results of the analyses revealed no significant main effects

or interactions for either CEMG or ZGR. The mean change

scores by group for each variable are presented in the Table

4-4 below. The ANOVA tables, Table C-31 and C-32 are

presented in Appendix C.