TY - JOUR
T1 - Response inhibition failure to visual stimuli paired with a "single-type" stressor in PTSD patients
T2 - An fMRI pilot study
AU - Brunetti, Marcella
AU - Sepede, Gianna
AU - Ferretti, Antonio
AU - Mingoia, Gianluca
AU - Romani, Gian Luca
AU - Babiloni, Claudio
PY - 2015/5/1
Y1 - 2015/5/1
N2 - Previous neuroimaging evidence has shown an abnormal activation of the amygdala and prefrontal cortex in PTSD patients during fear conditioning and extinction. Nevertheless, the effects of a single-type adverse stressor on that circuit remain poorly explored. We tested the hypothesis that a single-type adverse episode is able to affect the prefrontal cortex and amygdala response to conditioned stimuli. To test this hypothesis, fMRI recordings were performed in PTSD patients and trauma-exposed controls during the observation of neutral and negative paired or non-paired pictures with an adverse stimulus by means of a single association. Results showed that left amygdala activation during negative reinforced stimuli was correlated with the score of PTSD clinical scale across all subjects. Furthermore, in the traumatized non-PTSD group, the activation of the dorso-medial prefrontal cortex and bilateral amygdala was lower during the observation of the reinforced (CS+) versus non-reinforced pictures (CS-) in response to emotionally negative stimuli. This was not the case in the PTSD patients. These results suggest that in PTSD patients, a single-episode conditioning unveils the failure of an inhibitory mechanism moderating the activity of the prefrontal cortex and amygdala in response to adverse and neutral stimuli.
AB - Previous neuroimaging evidence has shown an abnormal activation of the amygdala and prefrontal cortex in PTSD patients during fear conditioning and extinction. Nevertheless, the effects of a single-type adverse stressor on that circuit remain poorly explored. We tested the hypothesis that a single-type adverse episode is able to affect the prefrontal cortex and amygdala response to conditioned stimuli. To test this hypothesis, fMRI recordings were performed in PTSD patients and trauma-exposed controls during the observation of neutral and negative paired or non-paired pictures with an adverse stimulus by means of a single association. Results showed that left amygdala activation during negative reinforced stimuli was correlated with the score of PTSD clinical scale across all subjects. Furthermore, in the traumatized non-PTSD group, the activation of the dorso-medial prefrontal cortex and bilateral amygdala was lower during the observation of the reinforced (CS+) versus non-reinforced pictures (CS-) in response to emotionally negative stimuli. This was not the case in the PTSD patients. These results suggest that in PTSD patients, a single-episode conditioning unveils the failure of an inhibitory mechanism moderating the activity of the prefrontal cortex and amygdala in response to adverse and neutral stimuli.
KW - Amygdala
KW - Conditioning
KW - Emotion
KW - Functional magnetic resonance imaging (fMRI)
KW - Post-traumatic stress disorder (PTSD)
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U2 - 10.1016/j.brainresbull.2015.03.001
DO - 10.1016/j.brainresbull.2015.03.001
M3 - Article
C2 - 25791360
AN - SCOPUS:84925447542
VL - 114
SP - 20
EP - 30
JO - Brain Research Bulletin
JF - Brain Research Bulletin
SN - 0361-9230
ER -