This investigation was designed to test the hypothesis that ear
advantage on a dichotic listening (DL) task of pitch discrimination
reflects asymmetries in the metabolic activities of the temporal lobes.
Fourteen normal subjects, with either a left-ear advantage (LEA) (n = 9) or
a right-ear advantage (REA) (n = 5) on the DL task, underwent measurements
of regional cerebral blood flow (rCBF) during a resting baseline condition
and during performance on the DL task. For both groups, the DL task was
associated with selective and significant increases in rCBF to the
contralateral posterior temporal lobe. Our finding of selective rCBF
activation with dichotic stimulation may have potential implications for an
understanding of the functional organization of the cerebral
hemispheres.Abstract Teaser