Linguistic lateralization and asymmetries in interhemispheric transmission time.

The Interhemispheric Conduction Delay (ICD) theory of cerebral lateralization claims that longer interhemispheric transfer times (IHTT's) should result in greater functional lateralization for time-critical tasks. IHTT was estimated in 40 normal participants using both a visual and an auditory version of the Poffenberger (1912) paradigm. There was a significant response-hand by side-of-presentation interaction, and the length of IHTT for auditory information being transferred from the right to left hemisphere was significantly related to linguistic lateralization as assessed with a dichotic-listening task. These results support the ICD theory of cerebral lateralization.