Corpus callosum differences associated with persistent stuttering in adults

Abstract

Recent studies have implicated anatomical differences in speech-relevant brain regions of adults who stutter (AWS) compared to normally fluent adults (NFA). The present study focused on the region of the corpus callosum (CC) which is involved in interhemispheric processing between the left and right cerebral hemispheres. Two-dimensional segmentation of area and voxel based morphometry were used to evaluate the corpus callosum. Results revealed that the rostrum and anterior midbody of the CC was larger in AWS than NFA. In addition, the overall callosa area was larger in AWS than NFA. The group comparison of white matter volume showed a cluster of increased white matter volume predominantly encompassing the rostrum across the midline portion in AWS. These results potentially reflect anatomical changes associated with differences in the hemispheric distribution of language processes that has been reported previously in AWS. Educational objectives After reading this article, the reader will be able to: (1) summarize research findings on functional and anatomical differences between AWS and NFA; (2) summarize research findings on anatomical anomalies observed in AWS; (3) discuss the possible relationships between functional and anatomical aberrations in AWS; and (4) discuss how the findings of the present study may support results of previous behavioral investigations (e.g. dichotic listening) in AWS.

Corpus callosum morphology in children who stutter

“…Unlike our previous study that found a larger anterior CC in AWS (Choo et al, 2011), the current study did not detect any statistically significant differences in CC size and WM volume between children with persistent stuttering, children who recovered from stuttering and typically developing children. Reconciling these findings between children and adults is challenging but could involve the protracted and nonlinear growth pattern of the CC.…”

“…We recently reported that the overall area of the corpus callosum (CC) and anterior portion of the CC was larger in adults who stutter (AWS) compared to normally fluent adults (Choo et al, 2011). Generally, a larger CC is associated with right hemisphere dominance or reduced hemispheric asymmetry for speech (Dorion et al, 2000; Gootjes et al, 2006; O’Kusky et al, 1988), which is consistent with neurological reports of increased right hemisphere activation or a lack of left hemisphere dominance in stuttering (De Nil et al, 2001; Fox et al, 1996; Neumann et al, 2003, 2005).…”

An exploration of dichotic listening among adults who stutter

“…The findings from the current study using dichotic listening infer the same findings of this widespread right hemisphere activation for AWS. Furthermore, the recent findings by Choo et al (2011) seem particularly relevant to the present results. These researchers found the overall size of the corpus callosum to be large in AWS compared to AWNS.…”

“…areas associated with self-monitoring, comprehension & fluency) were activated in adults who do not stutter (AWNS) but not among AWS. Structural anomalies of the corpus callosum among AWS were recently reported by Choo et al (2011). These researchers found that AWS exhibited a larger overall callosa compared to AWNS, and suggested that this size difference could be linked to atypical brain function.…”

Pesquisa do efeito de supressão e do processamento auditivo em indivíduos que gaguejam

“…Some studies have shown evidence of decreased activity in the left auditory cortex prior to speech-language therapy and normal or improved activity levels immediately after therapy (3) . Other studies have indicated neuroanatomical differences between individuals who stutter and non-stutterers (18,19) . Some other studies have demonstrated decreased auditory cortex activation and hyperactivation of the motor regions (5) .…”