Behavioral and multimodal neuroimaging evidence for a deficit in brain timing networks in stuttering: a hypothesis and theory

Abstract

The fluent production of speech requires accurately timed movements. In this article, we propose that a deficit in brain timing networks is one of the core neurophysiological deficits in stuttering. We first discuss the experimental evidence supporting the involvement of the basal ganglia and supplementary motor area (SMA) in stuttering and the involvement of the cerebellum as a possible mechanism for compensating for the neural deficits that underlie stuttering. Next, we outline the involvement of the right inferior frontal gyrus (IFG) as another putative compensatory locus in stuttering and suggest a role for this structure in an expanded core timing-network. Subsequently, we review behavioral studies of timing in people who stutter and examine their behavioral performance as compared to people who do not stutter. Finally, we highlight challenges to existing research and provide avenues for future research with specific hypotheses.

Speaking-related changes in cortical functional connectivity associated with assisted and spontaneous recovery from developmental stuttering

“…Please note that works have discussed the compensatory role of the cerebellum in stuttering (Alm et al, 2007;Etchell et al, 2014 andYang et al, 2016). Comment: The terms sex and gender are often used interchangeably.…”

“…The whole brain group comparison did not reveal significant positive connectivity when a voxel-wise correction for multiple comparisons was applied. Yet, when the original threshold of p<0.001, uncorrected, as in (Kell et al, 2009), was applied for the PPI*group interaction, there was increased connectivity between the left BA 47/12 and the superior cerebellum, a region that has previously been associated with compensation attempts and therapy effects in PS (Etchell, Johnson, & Sowman, 2014; Lu et al, 2012;Sitek et al, 2016; Yang et al, 2016). We thus decided to report this effect although it is not corrected for multiple comparisons.…”

Temporal variability in sung productions of adolescents who stutter

“…Jungblut et al (2014), studying apraxia of speech in aphasic patients, have put forward the idea that singing may enhance and reeducate speech motor capacities, in particular temporal planning, programming and sequencing of speech movements via its rhythmic structure. Following this idea, the present study investigates temporal aspects of articulation in singing and perceptually fluent speech in stuttering, a speech fluency disorder that is characterized by deficits in speech motor control (e.g., Civier, Tasko,[ 6 4 _ T D $ D I F F ] & Guenther, 2010; Ludlow & Loucks, 2003;Namasivayam & van Lieshout, 2011;Zimmermann, 1980), but also potential deficits in temporal processing (Alm, 2004;Etchell, Johnson, & Sowman, 2014;Etchell, Ryan, Martin, Johnson, & Sowman, 2016;Falk, Müller, & Dalla Bella, 2015;Van Riper, 1982;Wieland, McAuley, Dilley, & Chang, 2015).…”

Evaluation of Vocal Fold Motion During Blocks in Adults Who Stutter

“…However, blocks in AWS occur in various vocal fold positions, which suggests that the origin of this disorder is at a level higher than the respiratory centers in the pons and medulla oblongata, and that it does not involve the laryngeal motor neurons. The findings of this study are related to a deficit in brain timing networks of speech planning and timing cues for the initiation and execution of motor sequences in stuttering [22][23][24].…”