Altering risky decision-making: Influence of impulsivity on the neuromodulation of prefrontal cortex

Abstract

The prefrontal cortex (PFC) subserves complex cognitive abilities, including risky decision-making; the modulation of this brain area is shown to alter the way people take risks. Yet, neuromodulation of the PFC in relation to risk-taking behavior remains relatively less well-studied. Moreover, the psychological variables that influence such neuromodulation remain poorly understood. To address these issues, 16 participants took part in 3 experimental sessions on separate days. They received: (i) left anodal–right cathodal transcranial direct current stimulation (tDCS); (ii) left cathodal–right anodal stimulation; or (iii) sham stimulation while they completed two risk-taking tasks. They also measured on several cognitive–affective abilities and personality traits. It was revealed that left cathodal–right anodal stimulation led to significantly reduced risk-taking under a context of haste. The reduction of risk-taking (relative to sham) correlated with state and trait impulsivity, such that the effect was larger in more impulsive individuals. For these individuals, the tDCS effect size was considered to be large (generalized partial η² > .17). The effect of prefrontal-neuromodulation in reducing risk-taking was influenced by baseline impulsivity, reflecting a state-dependent effect of neuromodulation on the PFC. The results of this study carry important insights into the use of neuromodulation to alter higher cognition.

KEYWORDS:

• Transcranial direct current stimulation
• Risky decision-making
• Frontal lobe
• Stroop
• Barratt Impulsivity Scale

No potential conflict of interest was reported by the author.

Additional information

Funding

This work was supported by the May Endowed Professorship of The University of Hong Kong and the Research Grant Council Humanities and Social Sciences Prestigious Fellowship [grant number HKU703-HSS-13]. The funder had no roles in study design, data collection and analysis, decision to publish, or preparation of the manuscript.