Elderly Adults Became Aggressive than Younger Adults in a Simulated Traffic Jam: Enhanced Left Frontal Brain Activity Associated with Approach Motivation

Abstract

Previous studies suggest that left-superior asymmetry in brain activity reflects the approach motivation of anger, i.e., when people get upset asymmetry increases. It is unclear whether this asymmetry of brain activity reflects blood flow as evidenced by near-infrared spectroscopy (NIRS). This asymmetry may be greater in elderly adults than in younger adults because of their weaker inhibitory potential in the frontal lobe. The present study showed that elderly participants exhibited left-superior brain activity (front-dorsolateral area) in response to a traffic jam created by a driving simulator, whereas the young adults did not. In addition, slowing down of driving speed in response to unknown car trouble did not yield asymmetric brain activity in the frontal lobe in either younger or older adults. These results suggest that (1) only elderly adults experience subjective anger in a stimulated traffic jam, and (2) elderly adults exhibit left-superior frontal brain activity as evidenced by their NIRS scores. This seems to reflect increased approach motivation (i.e., anger), which suggests vulnerability in the inhibitory potential of elderly adults.