The Effects of Vocal Intonation in Digit Span Testing

Abstract

”Digit Span” subtests appear on many individual measures of intellectual and cognitive functioning and typically are interpreted as a reflection of individual skills. However, variations in the presentation of stimuli may affect results on these measures. Intonation, the drop in pitch of the examiner's voice, may influence performance by serving to signal the end of a digit series and to cue initiation of recall strategies. Eighty-two normal adults responded to two equivalent digit span sets. The recorded sets differed in presentation: continued monotone vs. a drop in pitch for final digits. Repeated measures ANOVA revealed a main effect for the experimental condition of intonation. The level of recall was significantly greater in the presence of a drop in voice at the end of a digit series (p < .0006). A comparison of marginal means revealed significantly better performance on digits forward vs. reversed (p < .0001). Precision in assessment practices and implications for the significance of cuing in intervention strategies are discussed.