Impulsivity and frontal asymmetry in substance-dependent individuals.
Right-frontal cortical activity at rest has been associated with impulsive and aggressive behaviors. Impulsivity has also been shown to play an important role in substance dependence as an antecedent and consequence of drug use. Past research has suggested that impulsivity is a multi-dimensional construct, with characteristic factors observed throughout different stages of a drug abuse trajectory. The present study sought to investigate frontal asymmetry in impulsive versus not-impulsive substance-dependent individuals receiving rehabilitation treatment. Eighteen male substance-dependent individuals (impulsive = 10) receiving treatment were recruited to participate in a resting EEG paradigm to assess frontal cortical activity. Results from a mixed-design ANOVA analysis showed a trend for impulsive individuals towards increased right relative to left frontal cortical activity compared to non-impulsive individuals. This effect was observed at mid-frontal electrode sites. Results suggest that increased right frontal cortical activity could be associated to impulsivity manifested during the abstinent/rehabilitation stage of drug abuse.