Age differences in intention to left and right hemispace using a dichotic listening paradigm.
This study assessed the influence of age (younger women and elderly women living in communities) on cerebral laterality using dichotic listening. Previous research has purported to show a relative right cerebral decline with age. To date, however, research on the right hemiaging hypothesis has provided mixed findings. It is possible that these mixed findings are caused by use of simple versus complex dichotic listening tasks. As a test of this hypothesis, older women were expected to have a heightened right ear advantage (REA) for phonemic speech sounds and greater difficulty switching intention to the left ear when instructed to focus to either the left or the right ear. No age difference was found using the traditional presentation of concurrent phonemes. However, the right hemiaging hypothesis was supported on the intentional task, in which older women were less able to switch intention to the left but not to the right ear. Implications for right hemiaging are discussed.