Interhemispheric inhibition, intrahemispheric activation, and lexical capacities of the right hemisphere: A tachistoscopic, divided visual-field study in normal subjects

This study proposes that the lexical-semantic capacities of the right hemis phere (RH) are underestimated in normal subjects and reexamines them in a " dynamic model" framework. As expected, overloading the left hemisphere by c ombining a lexical-decision task presented in divided visual field with a c oncurrent heavy verbal memory load, and activating the RH by combining the lexical-decision task with a concurrent visuo-imaged memory load, lead to e nhanced left visual field-RH lexical performance. The RH appears to support a larger lexical-semantic network than suggested in the literature, includ ing representations for long and nonimageable words, and the accessibility threshold for the representations stored therein is modulated by hemispheri c activation-inhibition mechanisms. (C) 2000 Academic Press.