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Neural signatures of conditioning, extinction learning, and extinction recall in posttraumatic stress disorder: a meta-analysis of functional magnetic resonance imaging studies

Published online by Cambridge University Press:  01 July 2019

Benjamin Suarez-Jimenez*
Affiliation:
Department of Psychiatry, Columbia University Medical Center, New York, USA New York State Psychiatric Institute, New York, USA
Anton Albajes-Eizagirre
Affiliation:
FIDMAG Germanes Hospitalàries, CIBERSAM, Sant Boi de Llobregat, Barcelona, Spain
Amit Lazarov
Affiliation:
Department of Psychiatry, Columbia University Medical Center, New York, USA New York State Psychiatric Institute, New York, USA School of Psychological Sciences, Tel Aviv University, Tel Aviv, Israel
Xi Zhu
Affiliation:
Department of Psychiatry, Columbia University Medical Center, New York, USA New York State Psychiatric Institute, New York, USA
Ben J. Harrison
Affiliation:
Department of Psychiatry, Melbourne Neuropsychiatry Centre, The University of Melbourne and Melbourne Health, Victoria, Australia
Joaquim Radua*
Affiliation:
FIDMAG Germanes Hospitalàries, CIBERSAM, Sant Boi de Llobregat, Barcelona, Spain Institute of Psychiatry, King's College London, De Crespigny Park, London, UK Department of Clinical Neuroscience, Centre for Psychiatric Research and Education, Karolinska Institutet, Stockholm, Sweden Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), CIBERSAM, Barcelona, Spain
Yuval Neria
Affiliation:
Department of Psychiatry, Columbia University Medical Center, New York, USA New York State Psychiatric Institute, New York, USA
Miquel A. Fullana
Affiliation:
FIDMAG Germanes Hospitalàries, CIBERSAM, Sant Boi de Llobregat, Barcelona, Spain Department of Psychiatry, Universitat Autònoma de Barcelona, Barcelona, Spain
*
Author for correspondence: Benjamin Suarez-Jimenez, E-mail: bs3021@cumc.columbia.edu and Joaquim Radua, E-mail: joaquim.radua@kcl.ac.uk
Author for correspondence: Benjamin Suarez-Jimenez, E-mail: bs3021@cumc.columbia.edu and Joaquim Radua, E-mail: joaquim.radua@kcl.ac.uk

Abstract

Background

Establishing neurobiological markers of posttraumatic stress disorder (PTSD) is essential to aid in diagnosis and treatment development. Fear processing deficits are central to PTSD, and their neural signatures may be used as such markers.

Methods

Here, we conducted a meta-analysis of seven Pavlovian fear conditioning fMRI studies comparing 156 patients with PTSD and 148 trauma-exposed healthy controls (TEHC) using seed-based d-mapping, to contrast neural correlates of experimental phases, namely conditioning, extinction learning, and extinction recall.

Results

Patients with PTSD, as compared to TEHCs, exhibited increased activation in the anterior hippocampus (extending to the amygdala) and medial prefrontal cortex during conditioning; in the anterior hippocampus-amygdala regions during extinction learning; and in the anterior hippocampus-amygdala and medial prefrontal areas during extinction recall. Yet, patients with PTSD have shown an overall decreased activation in the thalamus during all phases in this meta-analysis.

Conclusion

Findings from this metanalysis suggest that PTSD is characterized by increased activation in areas related to salience and threat, and lower activation in the thalamus, a key relay hub between subcortical areas. If replicated, these fear network alterations may serve as objective diagnostic markers for PTSD, and potential targets for novel treatment development, including pharmacological and brain stimulation interventions. Future longitudinal studies are needed to examine whether these observed network alteration in PTSD are the cause or the consequence of PTSD.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 2019

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Footnotes

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References

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Neural signatures of conditioning, extinction learning, and extinction recall in posttraumatic stress disorder: a meta-analysis of functional magnetic resonance imaging studies
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