Neurophysiological influence of musical training on speech perception

Abstract

Does musical training affect our perception of speech? For example, does learning to play a musical instrument modify the neural circuitry for auditory processing in a way that improves one's ability to perceive speech more clearly in noisy environments? If so, can speech perception in individuals with hearing loss (HL), who struggle in noisy situations, benefit from musical training? While music and speech exhibit some specialization in neural processing, there is evidence suggesting that skills acquired through musical training for specific acoustical processes may transfer to, and thereby improve, speech perception. The neurophysiological mechanisms underlying the influence of musical training on speech processing and the extent of this influence remains a rich area to be explored. A prerequisite for such transfer is the facilitation of greater neurophysiological overlap between speech and music processing following musical training. This review first establishes a neurophysiological link between musical training and speech perception, and subsequently provides further hypotheses on the neurophysiological implications of musical training on speech perception in adverse acoustical environments and in individuals with HL.

Keywords: EEG; MEG; auditory cortex; hearing loss; musical training; neuroplasticity; speech in noise; speech perception.

Figure 1

Auditory-evoked potentials (AEPs). AEP waveform for piano tone at the frontal channel Fz for 34 participants (averaged over musicians and non-musicians). The Na–Pa–Nb–P1 complex represents the middle latency response (MLR) originating in primary auditory cortex (A1). The N1 and P2 components represent activity originating in the surrounding belt areas of A1. Based on data from Shahin et al. (2003).

Figure 2

P2 indexes spectral complexity and is enhanced in musicians. (A) Temporal (top) and spectral (bottom) profiles of Pure, Piano 0, Piano 2, and Piano 8 tones. The pure tone had only the fundamental frequency (f₀, C4 notation), and Piano 0, Piano 2, and Piano 8 have the f₀, f₀+ first 2 harmonics, and f₀+ first 8 harmonics, respectively. Piano 0, Piano 2, and Piano 8 have the temporal envelope of the Piano C4 notation. (B) Root mean square (RMS) of auditory-evoked potential (AEP) waveforms for all channels (32; averaging across all stimuli) for musicians and non-musicians. (C) P2 RMS peak values for musicians and non-musicians for all stimuli. Based on data from Shahin et al. (2005). The error bars depict 1 SE.

Figure 3

P2 indexes pitch and is enhanced in musicians. Left, scalp current density topography for the P2 component occurring at about 185 ms. Right, amplitude of the P2 response is shown for pure tone in the musicians (n = 20) and non-musicians (n = 14). The error bars depict 1 SE. Based on data from Shahin et al. (2003).