Executive functioning and lateralized semantic priming in older adults

Normal aging is associated with a number of cognitive deficits, including changes in executive functioning. Research suggests that hemispheric asymmetry during certain tasks becomes less pronounced in the elderly, reflected in greater bilateral patterns of cortical activation among older adults. Forty-two younger adults and thirty-five older adults were administered a battery of neuropsychological tests sensitive to frontal functioning. In addition, they completed a lexical decision task to assess lateralized implicit priming at two stimulus onset asynchronies (50 and 750 ms). Results of accuracy and reaction time data support Cabeza's model of reduced asymmetry in older adults completing a semantic priming task. Analysis of the contribution of executive functioning revealed its importance in semantic memory processing.