Tap your hand if you feel the beat: differential effects of tapping in melodic intonation therapy

Abstract

ABSTRACT Background Melodic Intonation Therapy (MIT) is a structured, intensive therapy for recovery of verbal output in people with nonfluent, Broca’s type, aphasia. Stemming from the observation that people with nonfluent aphasia can sometimes sing fluently, MIT was developed with two distinctive “musical” features. The first is intonation of phrases, typically over a two-pitch interval, in a chant-like connected form. The second is pacing syllable initiation with a steady rhythmic tapping of the client’s hand on a table. Aims Research has suggested that people with aphasia may have a higher-than-typical prevalence of rhythm processing deficits. The present study investigates whether these deficits might affect therapeutic results from MIT. We hypothesized that a comparison of treatment with and without tapping would show positive treatment effects from the inclusion of tapping. We further hypothesized that the effect of tapping may be different, or even opposite, for people with rhythm processing deficits. Methods & Procedures The study included three participants who underwent treatment with MIT in two 5-week treatment blocks: one with tapping, and one without. Three sets of phrases were balanced for phonetic complexity, syntactic structure, and baseline performance. A set was assigned to each treatment condition, and the third set remained untrained. Spoken repetition ability across all sets was tested at baseline, between blocks, at the close of therapy, at 5-week follow up, and in probes each week throughout treatment. Propositional speech was also assessed at baseline and milestone testing points. Outcomes & Results Results showed that two participants who were assessed as having an intact ability to tap to the beat of music – intact entrainment – realized stronger treatment effects with rhythmic tapping. The third participant, who was assessed as having impaired entrainment, showed greater treatment effects from treatment without tapping. Conclusions These results suggest that testing individual MIT candidates for the ability to tap along to music, and modifying clinical treatment protocols accordingly, may result in greater therapeutic effectiveness of MIT for entrainment-impaired clients.