Hostname: page-component-7c8c6479df-27gpq Total loading time: 0 Render date: 2024-03-28T20:02:10.640Z Has data issue: false hasContentIssue false

Positron emission tomographic imaging of neural correlates of a fear acquisition and extinction paradigm in women with childhood sexual-abuse-related post-traumatic stress disorder

Published online by Cambridge University Press:  29 September 2004

J. DOUGLAS BREMNER
Affiliation:
Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA Department of Radiology, Emory University School of Medicine, Atlanta, GA Emory Center for Positron Emission Tomography, Emory University School of Medicine, Atlanta, GA Atlanta VAMC, Decatur, GA
ERIC VERMETTEN
Affiliation:
Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA
CHRISTIAN SCHMAHL
Affiliation:
Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA
VIOLA VACCARINO
Affiliation:
Department of Internal Medicine (Cardiology), Emory University School of Medicine, Atlanta, GA Atlanta VAMC, Decatur, GA
MEENA VYTHILINGAM
Affiliation:
Mood and Anxiety Disorders Program, National Institute of Mental Health, Bethesda, MD, USA
NADEEM AFZAL
Affiliation:
Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA
CHRISTIAN GRILLON
Affiliation:
Mood and Anxiety Disorders Program, National Institute of Mental Health, Bethesda, MD, USA
DENNIS S. CHARNEY
Affiliation:
Mood and Anxiety Disorders Program, National Institute of Mental Health, Bethesda, MD, USA

Abstract

Background. In the conditioned fear paradigm, repeated pairing of an aversive unconditioned stimulus (US) (e.g. electric shock) with a neutral conditioned stimulus (CS) (e.g. bright light) results in a conditioned fear response to the light alone. Animal studies have shown that the amygdala plays a critical role in acquisition of conditioned fear responses, while the medial prefrontal cortex (including anterior cingulate), through inhibition of amygdala responsiveness, has been hypothesized to play a role in extinction of fear responses. No studies have examined neural correlates of fear conditioning and extinction in patients with post-traumatic stress disorder (PTSD).

Method. Women with early childhood sexual-abuse-related PTSD (n=8) and women without abuse or PTSD (n=11) underwent measurement of psychophysiological (skin conductance) responding as well as positron emission tomographic (PET) measurement of cerebral blood flow during habituation, acquisition and extinction conditions. During habituation subjects were repeatedly exposed to a blue square on a screen. During acquisition, exposure to the blue square (CS) was paired with an electric shock to the forearm (US). With extinction, subjects were again exposed to the blue squares without shock. On a different day subjects went through the same procedure with electric shocks administered randomly in the absence of the blue square.

Results. Skin conductance responding to the CS was consistent with the development of conditioned responses with this paradigm. PTSD patients had increased left amygdala activation with fear acquisition, and decreased anterior cingulate function during extinction, relative to controls.

Conclusions. These findings implicate amygdala and anterior cingulate in the acquisition and extinction of fear responses, respectively, in PTSD.

Type
Research Article
Copyright
© 2004 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)