Verbal-performance IQ discrepancy and perception of Rhythm and Timbre

The Seashore Rhythm Tests, Form A and Form B, and the Timbre Test, Form A were administered to 90 strongly right-handed subjects placed in one of three WAIS Verbal-Performance IQ discrepancy groups. Some dissociation of performance on these tests was expected. As predicted, for the Rhythm Test Form A the High Performance group obtained significantly lower scores than the Equal group, which in turn had reliably lower scores than the High Verbal group. Converse predictions of group differences on Rhythm Test Form B were not confirmed. However, the predicted superiority of the High Performance group over the High Verbal group on Timbre Test Form A was found though the Equal group performed as well as the High Performance group. Thirty per cent of the High Performance group obtained scores on Rhythm Test Form A below the clinical cutoff of this test as opposed to only 6% of the Equal group and 0% of the High Verbal group.