2024-02-15 ニューヨーク大学 (NYU)
◆研究では、β活動が主に右側の前補助運動野で発生していると述べられており、この部分は動きや行動の一時停止または停止に重要な役割を果たしています。著者は、MEGが空間的な精度に関して制約があることを指摘し、したがって、より近くの右側前頭皮質背外側部などの脳の隣接領域でβ活動が発生している可能性もあると述べています。
<関連情報>
- https://www.nyu.edu/about/news-publications/news/2024/february/how-our-brains–beta-waves-predict-stuttering.html
- https://direct.mit.edu/nol/article/doi/10.1162/nol_a_00138/119560/Reactive-Inhibitory-Control-Precedes-Overt
反応性抑制制御があからさまな吃音事象に先行する Reactive Inhibitory Control Precedes Overt Stuttering Events
Joan Orpella,Graham Flick,M. Florencia Assaneo,Ravi Shroff,Liina Pylkkänen,David Poeppel,Eric S. Jackson
Neurobiology of Language Published:February 14 2024
DOI:https://doi.org/10.1162/nol_a_00138
Abstract
Research points to neurofunctional differences underlying fluent speech between stutterers and non-stutterers. Considerably less work has focused on processes that underlie stuttered vs. fluent speech. Additionally, most of this research has focused on speech motor processes despite contributions from cognitive processes prior to the onset of stuttered speech. We used MEG to test the hypothesis that reactive inhibitory control is triggered prior to stuttered speech. Twenty-nine stutterers completed a delayed-response task that featured a cue (prior to a go cue) signaling the imminent requirement to produce a word that was either stuttered or fluent. Consistent with our hypothesis, we observed increased beta power likely emanating from the R-preSMA—an area implicated in reactive inhibitory control—in response to the cue preceding stuttered vs. fluent productions. Beta power differences between stuttered and fluent trials correlated with stuttering severity and participants’ percentage of trials stuttered increased exponentially with beta power in the R-preSMA. Trial-by-trial beta power modulations in the R-preSMA following the cue predicted whether a trial would be stuttered or fluent. Stuttered trials were also associated with delayed speech onset suggesting an overall slowing or freezing of the speech motor system that may be a consequence of inhibitory control. Post-hoc analyses revealed that independently-generated anticipated words were associated with greater beta power and more stuttering than researcher-assisted anticipated words, pointing to a relationship between self-perceived likelihood of stuttering (i.e., anticipation) and inhibitory control. This work offers a neurocognitive account of stuttering by characterizing cognitive processes that precede overt stuttering events.
