A pilot study to investigate the induction and manipulation of learned helplessness in healthy adults

Abstract

Eliminating the controllability of a noxious stimulus may induce a learned helplessness (LH) that resembles aspects of depression and post-traumatic stress disorder (PTSD). This study examined whether repetitive transcranial magnetic stimulation (rTMS) of the left dorsolateral prefrontal cortex (DLPFC) promotes resilience in an aversive stimulus model of LH. All 55 participants were told that an undisclosed sequence of button presses would terminate an aversive stimulus on their forearm. In truth, only half had control (+C). The other half had no control (-C). All participants received real (R) or sham (S) left DLPFC rTMS during the paradigm (+C/R, -C/S,+C/S,-C/R). We evaluated the cognitive effects of LH using an anagram task. The LH paradigm successfully reduced perceived control in the -C groups. As predicted, the +C/R and +C/S groups tended to give up less quickly and take less time to solve each anagram than did the -C/S group. Superior anagram performance in the -C/R group approached statistical significance. Our preliminary results suggest that manipulating the controllability of an aversive stimulus may induce an LH effect that manifests as impaired anagram performance. Further research is needed to refine this model and determine if DLPFC rTMS mitigates any LH effects.

Keywords: Depression; Learned helplessness; Post-traumatic stress disorder; Prefrontal cortex; Stress; rTMS.