Temporal sequence effects in auditory oddity discrimination

The oddity method was used in assessing pitch, loudness, simultaneous tone, successive tone, and speech sound discrimination in 35 normal children and 15 children with learning problems. With this method three auditory stimuli are presented, two of which are identical, and the S is required to indicate the temporal position of the odd stimulus. For both groups, discrimination was most accurate when the odd stimulus was in the third position. These results could be explained by assuming that the oddity response was based upon successive Same-Different judgments of the first and second stimuli and the second and third stimuli, since a correct response to third-position oddity would require only a Same judgment of the first and second stimuli. Other findings were not as easily explained by this simple model, and alternative hypotheses are discussed.