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4. During prize anticipation, zygomatic EMG reactivity will

 be similar or greater for LHD compared to NHD patients,

 whereas RHD patients will show smaller zygomatic EMG

 compared to NHD patients. For LHD and NHD groups,

 zygomatic EMG will be greater for prize compared to no

 reward trials. However, differences in zygomatic EMG

 will be attenuated between prize and no prize control

 trials in RHD patients.

B) Bivalent Emotion Model: According to this view, patients

with RHD should demonstrate attenuated anxiety during the

shock anticipation condition (relative to NHD controls), and

either normal or enhanced pleasant feelings during

anticipatory reward condition. In contrast, patients with

LHD should demonstrate attenuated pleasant feelings during

the anticipatory reward condition (relative to NHD subjects)

and either normal or enhanced negative feelings during the

anticipatory shock task. These results may be most

pronounced in patients with anterior-extending lesions.

Specific predictions are as follows:

1. During shock anticipation, the LHD subjects will have

 greater or similar HR responding compared to the NHD

 group, whereas RHD subjects will have smaller HR

 responding relative to NHD subjects. Additionally, LHD

 and NHD patients will display greater HR responding

 during shock relative to no shock trials, whereas HR

 responding in RHD patients will not differ between