Sympathectomy disrupts feedback from the viscera

Researchers have examined the role of autonomic feedback in emotional experience using the heartbeat detection paradigm. Katkin et al. (1982) found that some normal subjects can accurately detect their heartbeats, and it was those individuals who had a stronger emotional response to negative slides as determined by self-report (hantas et al. 1982)
Experiments in animals demonstrate that sympathectomy may retard aversive conditioning (DiGusto and King, 1972) most likely because sympathectomy reduces fear.
In order for feedback to occur, there must be a means for the viscera and autonomic nervous system to become activated.

Clinical Neuropsychology

By Kenneth M. Heilman, Edward Valenstein

Published by Oxford University Press US, 2003

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