Deficient fear extinction memory in posttraumatic stress disorder

• Verfasst von: Wicking, Manon [VerfasserIn]
• Verfasst von: Ruttorf, Michaela [VerfasserIn]
• Verfasst von: Schad, Lothar R. [VerfasserIn]
• Verfasst von: Flor, Herta [VerfasserIn]
• Titel: Deficient fear extinction memory in posttraumatic stress disorder
• Verf.angabe: Manon Wicking, Frauke Steiger, Frauke Nees, Slawomira J. Diener, Oliver Grimm, Michaela Ruttorf, Lothar R. Schad, Tobias Winkelmann, Gustav Wirtz, Herta Flor
• E-Jahr: 2016
• Jahr: December 2016
• Umfang: 11 S.
• Fussnoten: Gesehen am 11.04.2019 ; Available online 26 September 2016
• Titel Quelle: Enthalten in: Neurobiology of learning and memory
• Ort Quelle: Orlando, Fla. : Academic Press, 1995
• Jahr Quelle: 2016
• Band/Heft Quelle: 136(2016), Seite 116-126
• ISSN Quelle: 1095-9564
• DOI: doi:10.1016/j.nlm.2016.09.016
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: Amygdala
• Sach-SW: Fear conditioning
• Sach-SW: Hippocampus
• Sach-SW: Posttraumatic stress disorder (PTSD)
• Sach-SW: Renewal
• Sach-SW: Safety learning
• K10plus-PPN: 1663144583

Abstract

Background - Posttraumatic stress disorder (PTSD) might be maintained by deficient extinction memory. We used a cued fear conditioning design with extinction and a post-extinction phase to provoke the return of fear and examined the role of the interplay of amygdala, hippocampus and prefrontal regions. - Methods - We compared 18 PTSD patients with two healthy control groups: 18 trauma-exposed subjects without PTSD (nonPTSD) and 18 healthy controls (HC) without trauma experience. They underwent a three-day ABC-conditioning procedure in a functional magnetic resonance imaging scanner. Two geometric shapes that served as conditioned stimuli (CS) were presented in the context of virtual reality scenes. Electric painful stimuli were delivered after one of the two shapes (CS+) during acquisition (in context A), while the other (CS−) was never paired with pain. Extinction was performed in context B and extinction memory was tested in a novel context C. - Results - The PTSD patients showed significantly higher differential skin conductance responses than the non-PTSD and HC and higher differential amygdala and hippocampus activity than the HC in context C. In addition, elevated arousal to the CS+ during extinction and to the CS− throughout the experiment was present in the PTSD patients but self-reported differential valence or contingency were not different. During extinction recall, differential amygdala activity correlated positively with the intensity of numbing and ventromedial prefrontal cortex activity correlated positively with behavioral avoidance. - Conclusions - PTSD patients show heightened return of fear in neural and peripheral measures. In addition, self-reported arousal was high to both danger (CS+) and safety (CS−) cues. These results suggest that a deficient maintenance of extinction and a failure to identify safety signals might contribute to PTSD symptoms, whereas non-PTSD subjects seem to show normal responses.