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Attention allocation in posttraumatic stress disorder: an eye-tracking study

Published online by Cambridge University Press:  26 February 2021

Amit Lazarov*
Affiliation:
School of Psychological, Tel-Aviv University, Tel-Aviv, Israel Department of Psychiatry, Columbia University Irving Medical Center, New York, NY, USA
Benjamin Suarez-Jimenez
Affiliation:
Department of Neuroscience, The Del Monte Institute for Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA Department of Psychiatry, Columbia University Irving Medical Center and New York State Psychiatric Institute, New York, NY, USA
Xi Zhu
Affiliation:
Department of Psychiatry, Columbia University Irving Medical Center and New York State Psychiatric Institute, New York, NY, USA
Daniel S. Pine
Affiliation:
Section on Developmental Affective Neuroscience, National Institute of Mental Health, Bethesda, MD, USA
Yair Bar-Haim
Affiliation:
School of Psychological Sciences and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
Yuval Neria
Affiliation:
Department of Psychiatry, Columbia University Irving Medical Center and New York State Psychiatric Institute, New York, NY, USA
*
Author for correspondence: Amit Lazarov, E-mail: [email protected]

Abstract

Background

Eye-tracking-based attentional research implicates sustained attention to threat in posttraumatic stress disorder (PTSD). However, most of this research employed small stimuli set-sizes, small samples that did not include both trauma-exposed healthy participants and non-trauma-exposed participants, and generally failed to report the reliability of used tasks and attention indices. Here, using an established eye-tracking paradigm, we explore attention processes to different negatively-valenced cues in PTSD while addressing these limitations.

Methods

PTSD patients (n = 37), trauma-exposed healthy controls (TEHC; n = 34), and healthy controls (HC; n = 30) freely viewed three blocks of 30 different matrices of faces, each presented for 6 s. Each block consisted of matrices depicting eight negatively-valenced faces (anger, fear, or sadness) and eight neutral faces. Gaze patterns on negative and neural areas of interest were compared. Internal consistency and test-retest reliability were evaluated for the entire sample and within groups.

Results

The two trauma-exposed groups dwelled longer on negatively-valenced faces over neutral faces, while HC participants showed the opposite pattern. This attentional bias was more prominent in the PTSD than the TEHC group. Similar results emerged for first-fixation dwell time, but with no differences between the two trauma-exposed groups. No group differences emerged for first-fixation latency or location. Internal consistency and 1-week test-retest reliability were adequate, across and within groups.

Conclusions

Sustained attention on negatively-valenced stimuli emerges as a potential target for therapeutic intervention in PTSD designed to divert attention away from negatively-valenced stimuli and toward neutral ones.

Type
Original Article
Copyright
Copyright © The Author(s), 2021. Published by Cambridge University Press

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