ABSTRACT
BACKGROUND:
Post-Traumatic Stress Disorder (
PTSD) is characterized by distinct behavioral and physiological changes. Given the significant impairments related to
PTSD, examination of the
biological underpinnings is crucial to the development of
theoretical models and improved
treatments of
PTSD.
METHODS:
We used an attentional interference task using emotional distracters to test for top-down versus bottom-up dysfunction in the interaction of cognitive-control circuitry and
emotion-processing circuitry. A total of 32
women with
PTSD (based on an interpersonal
trauma) and 21 matched controls were tested. Event-related
functional magnetic resonance imaging was carried out as participants directly attended to, or attempted to ignore,
fear-related stimuli.
RESULTS:
Compared to controls,
patients with
PTSD showed hyperactivity in several
brain regions, including the
amygdala, insula, as well as dorsal lateral and ventral PFC regions.
CONCLUSIONS:
These results are consistent with previous studies that have higher
amygdala and insular activation in
PTSD subjects. However, inhibition of
suppression of PFC regions is inconsistent with the
fear circuitry model hypothesized by prior
research. We suggest that the specific emotional conflict task used appears to target implicit or automatic
emotional regulation instead of explicit or effortful
emotional regulation. This is particularly relevant as it posited that emotional regulatory difficulties in
anxiety disorders such as
PTSD appear to occur in implicit forms of
emotion regulation.
