Heroin impairs map-picture-following and memory tasks dependent on gender and orientation of the tasks

Male and female heroin-dependent patients (HDPs) matched with "normal" people were tested on 4 topographical orientation tasks: schematic map-following, map-memory, schematic picture-following, and picture-memory tasks. The results showed that, in general, female HDPs demonstrated greater performance deficits in map-following and map-picture-memory tasks than did other participants. In the map-picture-following tasks, participants showed a preference for turning right versus turning left, reflected by lower correct scores and longer latencies in completing left-oriented tasks. In contrast, no difference in orientation preference was found for participants in memory tasks, except for female HDPs. Asymmetric dopamine receptor distribution in the brain, sex steroidal hormone, brain areas related to motor functioning and working memory, and gender-dependent lateralization may be involved in the different effects of heroin and rightward bias between men and women.