Page 281 - MEGIN Book Of Abstracts - 2023

National Intrepid Center of Excellence, Walter Reed National (Spearman rs = -0.38, p = 0.016). PCL-5 scores were also
Military Medical Center, Bethesda, MD, United States; Behav- negatively correlated with the recognition accuracy for
ioral Biology Branch, Walter Reed Army Institute of Research, original images (rs = -0.37, p = 0.02). Increases in theta
503 Robert Grant Ave, Silver Spring, MD 20910, United States. and gamma power and decreases in alpha and beta
Electronic address: [email protected] power were observed over distributed brain networks
during memory encoding. Higher PCL-5 scores were
ABSTRACT We studied the relationship between elec- associated with less suppression of beta band power
trophysiological markers of memory encoding, subse- in bilateral ventral and medial temporal regions and in
quent recognition performance, and severity of PTSD the left orbitofrontal cortex. These regions also showed
symptoms in service members with combat exposure positive correlations between the magnitude of sup-
(n = 40, age: 41.2 ± 7.2 years) and various levels of PTSD pression of beta power during encoding and subse-
symptom severity assessed using the PTSD Check List quent recognition accuracy. These findings indicate
for DSM V version (PCL-5). Brain activity was recorded that the lower recognition performance in participants
using magnetoencephalography during a serial presen- with greater PTSD symptom severity may be due in
tation of 86 images of outdoor scenes that were stud- part to ineffective encoding reflected in altered modu-
ied by participants for an upcoming recognition test. lation of beta band oscillatory activity.
In a second session, the original images were shown
intermixed with an equal number of novel images Keywords: Beta band oscillations, Magnetoencephalogra-
while participants performed the recognition task. Par- phy, Memory encoding, Post-traumatic stress disorder
ticipants recognized 76.0% ± 12.1% of the original im-
ages and correctly categorized as novel 89.9% ± 7.0% NeuroImage. Clinical (2020), Vol. 25 (31951934) (4
of the novel images. A negative correlation was present citations)
between PCL-5 scores and discrimination performance

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