An ERP study of attentional bias to drug cues in heroin dependence by using dot-probe task

Abstract

Electroencephalogram (EEG) contains a wealth of information of the brain cognitive activities. Previous studies have provided that the behavioral data of reaction time (RT) is the main evidence of the attentional bias (AB) to drug cues in the heroin dependence. It is the primary method of measuring AB among the addicts. In this paper, RT is used to test the AB of the heroin addict towards heroin-related cues by using the dot-probe task. Meanwhile, event-related potentials (ERPs) are used to compare the differences between heroin addicts and normal controls. The heroin-related dot-probe task is performed on the heroin addicts (n = 22) and health normal controls (n = 22). The results show that heroin addicts have more expeditious response when the dot located on the heroin-related picture (valid) compared with on the neutral picture (invalid). Meanwhile, it is opposite to controls. At onset of the images, the average amplitude of P1 and P2 show obvious differences between addicts and controls at FCz. When at onset of the dot, an increased N2 is elicited under the valid condition compared with the invalid condition, which appeared in heroin addicts and controls. The latency of P3 of the controls is longer than that of addicts at Pz. These findings suggest that heroin addicts have differences when processing heroin-related cues compared to controls.