Hemispheric priming affects right-ear advantage in dichotic listening.

The effects of hemispheric preactivation on dichotic listening performance were investigated in a sample of 45 right-handed male adults. The dichotic stimuli (/ka/, /ta/, /pa/, /ga/, /da/ and /ba/) were presented under three conditions: prior to the test session and during test pauses subjects were confronted with (1) verbal or (2) spatial tasks, and (3) in a control session subjects received no prior task. It was shown that recall accuracy from the right ear was significantly increased when subjects performed verbal tasks prior to the experiment as compared to those experimental conditions in which subjects had to perform a spatial or no special task. Left ear scores were unaffected by these manipulations. The results suggest that verbal tasks performed prior to the dichotic listening experiment primes the hemisphere for verbal stimuli, resulting in a superior dichotic listening performance. Possible consequences for dichotic listening research are discussed.