Beat synchronization predicts neural speech encoding and reading readiness in preschoolers

Abstract

Temporal cues are important for discerning word boundaries and syllable segments in speech; their perception facilitates language acquisition and development. Beat synchronization and neural encoding of speech reflect precision in processing temporal cues and have been linked to reading skills. In poor readers, diminished neural precision may contribute to rhythmic and phonological deficits. Here we establish links between beat synchronization and speech processing in children who have not yet begun to read: preschoolers who can entrain to an external beat have more faithful neural encoding of temporal modulations in speech and score higher on tests of early language skills. In summary, we propose precise neural encoding of temporal modulations as a key mechanism underlying reading acquisition. Because beat synchronization abilities emerge at an early age, these findings may inform strategies for early detection of and intervention for language-based learning disabilities.

Keywords: auditory processing; cABR; rhythm; speech envelope; temporal processing.

Fig. 1.

The ability to synchronize to a beat relates to neural encoding of speech and prereading language metrics. Data for Synchronizers are shown in red, data for Non-synchronizers in black. (A and B) Phase histograms (blue) of representative participants’ drum hits across a drumming session relative to stimulus (0°). (A) The Non-synchronizer’s drum hits are distributed randomly throughout the stimulus-phase cycle, with a negligible phase vector (black). (B) The Synchronizer’s drum hits cluster around a time region just before the stimulus, indicating the child is predicting the beat. The length of the mean phase vector (red) corresponds to the consistency of the relationship between the time of the drum hit and the time of onset of the stimulus. (C and D) Synchronizers (red) and Non-synchronizers (black) did not differ in broadband subcortical encoding of the speech syllable [da] in (C) quiet or (D) background noise. (E and F) Synchronizers benefit from selectively enhanced envelope precision encoding, as evinced by higher stimulus-to-response correlation values. (G–J) Synchronizers also performed better than Non-synchronizers on behavioral reading-related tasks measuring (G) phonological processing, (H) auditory short-term memory, (I) rapid naming, and (J) musical perception. *P < 0.05, **P < 0.01.

Fig. 2.

The relationship between beat synchronization and neural envelope encoding generalizes across a range of stimuli, and envelope precision correlates with drumming consistency. (A) Synchronizers (red) demonstrated more precise neural encoding of the speech envelope than Non-synchronizers (black) as evinced by greater correlations between stimulus and brainstem response envelopes across stimuli in both quiet and noise conditions. (B) Individual synchronization ability within the Synchronizers is correlated with more precise envelope encoding (a composite of [ba], [da], and [ga]).