Behavioral Laterality and Aging: The Free-Recall Dichotic-Listening Right-Ear Advantage Increases With Age.

The effect of aging on brain asymmetry was studied under consideration of possible confounding effects of known age-related decline in higher cognitive functioning. In a sample of 3,680 participants aged 20-79 years, laterality was assessed with a verbal, free-recall dichotic-listening paradigm with one stimulus pair presentation per trial, minimizing working-memory and cognitive-control demands during task performance. Laterality, reflected as right-ear preference for dichotic stimuli, was found to be increased in older age (above 60 years). This effect was due to a reduced report of left-ear stimuli, while the report of right-ear stimuli stayed on comparable levels across all ages.