The effects of acute anticipatory stress on frontal executive functions in healthy females

Abstract

Objective Results from previous studies show effects of stress hormones (cortisol) on cognitive functions, particularly those mediated by the hippocampus, but little research has examined the effects of cortisol on frontal executive functions, despite a preponderance of cortisol receptors in the frontal lobes. Existing research has focused on traditional measures of executive functions and the findings are inconsistent. The aim of the present study was to examine the effects of acute stress on frontal executive function using traditional tasks, and a more ecologically-valid task, the Zoo Map Test, which measures planning. Methods 40 healthy female undergraduates participated in the experiment. Stress was induced in the experimental condition through anticipation of a public speech, which would be evaluated by two psychologists, after which performance on the Verbal Fluency Test (VFT), Cognitive Estimation Test (CET), and Zoo Map Test (ZMT) was measured. Physiological (skin conductance and heart rate) and subjective measures of stress were assessed. Results Stress was successfully induced in the experimental condition. However, no significant differences were found between the stressed and unstressed groups on the traditional tests of executive function or on the ZMT. A trend towards the experimental group performing more quickly on the ZMT was observed.

Conclusions Acute anticipatory psychosocial stress in young, healthy females does impact on performance on the VFT, CET or ZMT. Stress hormones may simply not have an effect on frontal executive functions or, the stress induced was not sufficient to disrupt performance, or the great variability on the ZMT performance meant that significant differences could not be detected in this sample size due to insufficient power.