Left-hemispheric activation and self-infiltration:: Testing a neuropsychological model of internalization

Two studies examined self-infiltration (as indexed by a tendency toward false self-ascription of assigned tasks) and its relationship to the activation of the two hemispheres of the human brain. Unilateral muscle contractions of each hand were performed by participants to activate the contralateral hemisphere and influence self-infiltration (confusing assigned tasks as self-selected in memory). In both studies, self-infiltration was observed after right-hand muscle contractions (left-hemispheric activation) and was absent after left-hand muscle contractions (right-hemispheric activation). In addition, Study 2 replicated the relationship between self-infiltration and left-hemispheric activation using a line drawing task to estimate participants' relative hemispheric dominance.