Non-verbal sensorimotor timing deficits in children and adolescents who stutter

Abstract

There is growing evidence that motor and speech disorders co-occur during development. In the present study, we investigated whether stuttering, a developmental speech disorder, is associated with a predictive timing deficit in childhood and adolescence. By testing sensorimotor synchronization abilities, we aimed to assess whether predictive timing is dysfunctional in young participants who stutter (8–16 years). Twenty German children and adolescents who stutter and 43 non-stuttering participants matched for age and musical training were tested on their ability to synchronize their finger taps with periodic tone sequences and with a musical beat. Forty percent of children and 90% of adolescents who stutter displayed poor synchronization with both metronome and musical stimuli, falling below 2.5% of the estimated population based on the performance of the group without the disorder. Synchronization deficits were characterized by either lower synchronization accuracy or lower consistency or both. Lower accuracy resulted in an over-anticipation of the pacing event in participants who stutter. Moreover, individual profiles revealed that lower consistency was typical of participants that were severely stuttering. These findings support the idea that malfunctioning predictive timing during auditory–motor coupling plays a role in stuttering in children and adolescents.

BAASTA: Battery for the Assessment of Auditory Sensorimotor and Timing Abilities

“…Recent studies revealed that some of the tasks included in BAASTA, in particular paced tapping, are sensitive to peculiar disorders of beat-based timing in different populations. For example, synchronization consistency is particularly low in adult beat-deaf participants (Sowiński & Dalla Bella, 2013), in children suffering from developmental stuttering (Falk et al, 2015) and in preschoolers who score poorly in early language tests (e.g., phonological awareness and naming tasks; Woodruff Carr, Tierney, White-Schwoch, & Kraus, 2016;Woodruff Carr et al, 2014). Synchronization accuracy (i.e., whether participants anticipate or not the beat) is also impaired in children with developmental stuttering, who tend to anticipate the beat more than controls do.…”

“…Indeed, based on the data obtained in a relatively small sample of non-musicians, the battery can sensitively identify individual differences in perceptual and sensorimotor timing skills. Hence, BAASTA can serve to uncover individuals with spared or impaired rhythmic skills in healthy participants without musical training and in clinical populations (e.g., Benoit et al, 2014;Falk, Müller & Dalla Bella, 2015).…”

“…Circular statistics are not conditional on this constraint. This has the advantage that data from individuals showing poor synchronization can still be analyzed (e.g., Falk, Müller, & Dalla Bella, 2015;Kirschner & Tomasello, 2009;Pecenka & Keller, 2011;Sowiński & Dalla Bella, 2013), thus making circular statistics particularly well-suited to detect poor synchronization and to capture individual differences Woodruff Carr, White-Schwoch, Tierney, Strait, & Kraus, 2014).…”

“…The null hypothesis is rejected when R vector length is sufficiently large according to this test. Vector length data was submitted to a logit transformation (e.g., Falk et al, 2015) before conducting further analyses. In both paced tapping and synchronizationcontinuation tasks, the results in the two trials were averaged and submitted to further analyses.…”

“…Moreover, both simple and complex stimulus material (a single repeated tone vs. music) is used in the tests. Previous studies have shown that rhythm deficits are easier to detect with more complex auditory material (Sowiński & Dalla Bella, 2013;Falk et al, 2015). Therefore, we expect that the battery will be particularly sensitive to individual differences.…”