Neural Generators of the N2 Component for Abstinent Heroin Addicts in a Dot-Probe Task

Target-elicited N2 component of event-related potential (ERP) has been considered to be involved in target detection in the attentional processes. We aim to link the target-elicited N2 in a dot-probe task and the drug-related attention bias in heroin dependence and further estimate the brain regions involved in the generation of the target-elicited N2. We recorded 64-channel electroencephalograms (EEG) from 17 abstinent heroin addicts (AHAs) and 17 healthy controls (HCs) during the dot-probe visual task. Individual N2 sources were localized using exact low-resolution electromagnetic tomography (eLORETA). Compared to HCs, AHAs generated larger N2 amplitude in both congruent and incongruent conditions, suggesting that target detection processing in AHAs might require more attention resources. Moreover, N2 component was mainly generated in the Brodmann areas (BAs) 7, 23, 24, 31, 30, 32, and 40, implying that the frontoparietal cortex played a critical role in target detection processes.