Search Abstracts | Symposia | Slide Sessions | Poster Sessions
Rhythm disruptions in Parkinson’s disease and developmental stuttering: a comparative review of current knowledge
Poster Session C, Thursday, October 1, 10:45 am - 12:45 pm, Wangari Maathai
Valentine Lucquiault1, Abigail Grant2, Charlie Wiltshire2, Defne Abur1; 1University of Groningen, Groningen, NL, 2Bangor University, Bangor, UK
Introduction. Rhythm is an intricate, finely monitored feature of human behaviour. Disruptions to rhythm control can thus lead to a variety of symptoms in speech and body, as seen in Parkinson’s disease (PD) and developmental stuttering (DS). Parkinson's disease, a neurodegenerative disorder that develops in older age, affects both speech and body rhythm. Developmental stuttering is a motor disorder most prevalent in children that primarily affects speech fluency. Recent developments posit disrupted rhythm control as a potential aetiological factor in PD and in DS. From a behavioural perspective, speech symptoms of PD sometimes include acquired stuttering, or even the re-emergence of childhood stuttering. Trajectory analysis of gait freezes in PD exhibit temporal patterns resembling stuttering blocks. From a neurological perspective, the basal ganglia loop has been posited as a key locus for both PD and DS, thereby lending support to the hypothesis of central rhythm disruptions. Although behavioural and neurological results show similarities for rhythm control in PD and DS, studies are rarely comparable due to the lack of overlap in populations and methodologies; parallel investigations additionally remain scarce, and key observations are left unexplained. The present systematic review summarised the state of literature regarding comparative studies of PD and DS. The overarching goal was to identify promising research directions for the joint study of PD and DS, and for the design of theoretical models of rhythm control. Methods. A systematic review of experimental literature was conducted, which jointly investigated PD and DS following PRISMA guidelines. Reviewed databases were PubMed and Web of Science with search strings “Parkinson + stutter*” and “Parkinson + stammer*”. The review specifically targeted peer-reviewed journal articles written in English, which reported on experimental comparisons of PD and DS together. Studies of PD and DS alone and of parkinsonism or acquired stuttering were excluded, as were case studies, surveys, reviews, and meta-analyses. Results and Conclusions. The initial query returned 111 unique search results, of which 11 abstracts matched the inclusion criteria. After full review by two readers, six results did not meet the criteria (review n = 2, case study n =1, survey n = 1, not full-length article n = 1, duplicate under a different title n = 1), which narrowed down the scope to a final five articles. Three articles were qualitative descriptions of disfluency events; one article reported the communicative difficulties stemming from disfluency events; one article focused on verbal sequence learning skills. Two preliminary conclusions can be drawn. First, the small number of experimental studies comparing PD and DS highlight this direction as underexplored. Second and relatedly, the reviewed paradigms did not address the neural architecture involved in PD and DS. At the meeting, the five articles will be presented in detail, and future research directions leveraging PD and DS as a window into rhythm control will also be discussed. In particular, investigations into the role of dopamine in the basal ganglia will be proposed as a promising research direction to further our understanding of typical and atypical speech rhythm control.
Topic Areas: Multisensory or Sensorimotor Integration, Speech Motor Control