Stress-Induced Deficits in Working Memory and Visuo-Constructive Abilities in Special Operations Soldiers

doi:10.1016/j.biopsych.2006.04.021

Biological Psychiatry

Volume 60, Issue 7, 1 October 2006, Pages 722-729

https://doi.org/10.1016/j.biopsych.2006.04.021 Get rights and content

Background

Pre-clinical and clinical studies have shown acute stress may impair working memory and visuo-spatial ability. This study was designed to clarify the nature of stress-induced cognitive deficits in soldiers and how such deficits may contribute to operational or battlefield errors.

Methods

One hundred eighty-four Special Operations warfighters enrolled in Survival School completed pre-stress measures of dissociation and trauma exposure. Subjects were randomized to one of three assessment groups (Pre-stress, Stress, Post-stress) and were administered the Rey Ostereith Complex Figure (ROCF). All subjects completed post-stress measures of dissociation.

Results

ROCF copy and recall were normal in the Pre- and Post-stress groups. ROCF copy and recall were significantly impaired in the Stress Group. Stress group ROCF copy performance was piecemeal, and ROCF recall was impaired. Symptoms of dissociation were negatively associated with ROCF recall in the Stress group. Baseline dissociation and history of traumatic stress predicted cognitive impairment during stress.

Conclusions

Stress exposure impaired visuo-spatial capacity and working memory. In rats, monkeys, and humans, high dopamine and NE turnover in the PFC induce deficits in cognition and spatial working memory. Improved understanding of stress-induced cognitive deficits may assist in identification of soldiers at risk and lead to the development of better countermeasures.

Section snippets

Subjects in the Study

A total of 184 of 200 consecutively recruited male, active duty personnel [mean age 23 years, standard deviation (SD) = 4.1] were the subjects of this study. One hundred thirty subjects (69.9%) were single, and 54 (29%) were married. Overall, 166 subjects were men; 18 were women. As designated by their military operational specialty, 92 subjects were Navy pilots, 14 subjects were Marine aviators, and 78 were air wing support personnel. Recruitment of subjects was conducted by the investigators

ROCF Copy Data

The mean ROCF Copy scores for the Pre-stress, Stress, and Post-stress groups were 35.8, 33.4, and 35.4, respectively. General linear model univariate ANOVA indicated there was a significant effect of group (F(1,2) = 52.04; p < .000). Post hoc analyses (Tukey) indicated that this effect was due to a significantly lower ROCF Copy score in the Stress group (mean difference between Stress and Pre-stress group = 2.40 [standard error (SE) = .25]; p < .001; mean difference between Stress group and

Discussion

Performance on the ROCF was within the normal range for the pre-stress and post-stress groups. However, exposure to realistic levels of acute stress resulted in significant alterations in both ROCF copy procedure and ROCF recall scores. Contrary to our hypothesis, nearly all subjects exhibited abnormalities in visuo-constructive abilities when copying the Rey figure immediately after stress exposure. The piecemeal strategy used by these adults resembles that observed in pre-pubescent children

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Original articleStress-Induced Deficits in Working Memory and Visuo-Constructive Abilities in Special Operations Soldiers

Background

Methods

Results

Conclusions

Section snippets

Subjects in the Study

ROCF Copy Data

Discussion

Trends Cognit Sci

Biol Psychiatry

Arch Neuropsychol

Psychoneuroendocrinology

Brain Res

Arch Clin Neuropsychol

Brain Res

Arch Clin Neuropsychol

Biol Psychiatry

Biol Psychiatry

Biol Psychiatry

Biol Psychiatry

Int J Psychiatry Law

Arch Clin Neuropsychol

Biol Psychiatry

Catecholamine regulation of pre-frontal cortex

J Psychopharmacol

The biology of being frazzled

Science

Locus coeruleus, stress, and PTSD: Neurobiological and clinical parallels

Working Memory

Sustaining Performance during Continuous Operations: The US Army’s Sleep Management System

Rey-Ostereith figure: Psychometric characteristics in a geriatric sample

Clin Neuropsychol

Measurement of dissociative states with the Clinician-Administered Dissociative States Scale (CADSS)

J Traumatic Stress

Original article
Stress-Induced Deficits in Working Memory and Visuo-Constructive Abilities in Special Operations Soldiers