peripheral autonomic denervation affects fear and arousal

States of peripheral autonomic arousal are represented within brain regions that overlap those implicated in emotion Critchley et al. 2000a, Critchley et al. 2000b, Critchley et al. 2001a, Critchley et al. 2001b and Critchley et al. 2001c. Moreover, activity within areas involved in central autonomic control is modulated by feedback of peripheral autonomic responses (Critchley et al., 2001a). These autonomic arousal states bias emotional behavior and influence processes such as memory (e.g., Damasio et al. 1990,Cahill et al. 1994 and Cahill and McGaugh 1998). For example, amygdala is associated with memory enhancement for emotional material, a process thought to be mediated through the influence of states of arousal on amygdalo-hippocampal functional connectivity Cahill et al. 1994, Cahill and McGaugh 1998 and Cahill et al. 1999. Peripheral autonomic arousal may also influence conditioning, as suggested by pharmacological and motivational manipulations in animals Young et al. 1995 and Maren et al. 1994.
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