Initial Evidence of a Failure to Activate Right Anterior Insula During Affective Set Shifting in Posttraumatic Stress Disorder

Address correspondence and reprint requests to: Alan Simmons, PhD, E-mail: ansimmons{at}ucsd.edu.

	Abstract

Objective: Interoception is the sense of one's internal physiological, sensory, and emotional status. Extensive evidence supports a link between interoception and subjective experience. An altered ability to monitor or modulate interoception as it relates to subjective experience may provide a mechanistic explanation for the development of some forms of psychiatric illness. Methods: We investigated which neural networks are activated when anticipating a change in affective (and thus interoceptive) state, which we term "affective set-shifting," in 15 women with posttraumatic stress disorder (PTSD) related to intimate partner violence, and in 15 nontraumatized healthy volunteers. Results: Although both groups activated the dorsolateral prefrontal cortex during affective set shifting, the PTSD group showed significantly less activation in the right anterior insula than did the controls. Conclusions: These findings may suggest that although individuals with PTSD are cognitively aware of the impending shift in interoceptive state, they fail to appropriately activate neural circuitry involved in modulating interoceptive responses.

Key Words: Interoception, emotional set shifting, PTSD, insula, anticipation, DLPFC