The role of the premotor cortex in multisensory speech perception throughout adulthood: a rTMS study

Avril Treille 1 Marc Sato 2 Jean-Luc Schwartz 1 Coriandre Vilain 3 Pascale Tremblay 4
1 GIPSA-PCMD - PCMD
GIPSA-DPC - Département Parole et Cognition
3 GIPSA-Services - GIPSA-Services
GIPSA-lab - Grenoble Images Parole Signal Automatique
4 Laboratoire des Neurosciences de la parole et de l'audition (Québec) [Canada]
Centre de recherche de l’Institut universitaire en santé mentale de Québec [Canada]
Abstract : Although neurobiological models of language argue for a left lateralization of the audio-motor dorsal pathway during speech perception [1], the question of the role of the right and left premotor ventral (PMv) areas in multisensory speech integration processes remains largely unknown. What is the contribution of the hemispheric differentiation in the integration processing and what role do premotor areas play in these mechanisms? Further, given the known differences in speech perception accuracy for young and older adults and decreasing sensorial acuities with age, it is possible that the lateralization of multimodal integration processes evolves over time. In the present study, we explored the impact of inhibitory transcranial magnetic stimulation (rTMS) on the right and left PMv during auditory (A), visual (V) and tactile (T) unimodal conditions as well as during audio-visual (AV) and audio-tactile (AT) bimodal conditions across age. The experiment consisted of 2 rTMS sessions (related to the left and right PMv) conducted for each of the 24 healthy right-handed participants (16 females; mean 46±19 [19-78] years). Following completion of each session, participants performed a force-choice identification task. They were told that they would be presented with /pa/, /ta/ or /ka/ syllables in 5 different sensory modalities (A, V, AV, T, AT) and had to identify, as quickly as possible, the perceived syllable by pressing on one of three keys on a response pad. To increase task-difficulty, half the trials were presented in quiet, while the other half was presented in noise. Mixed-model ANOVAs were conducted on the mean accuracy and median reaction time (RT) data with the target region (left PMv/right PMv), the acoustic environment (noise/no noise), and the modality (A/AV/AT/V/T for the accuracy analysis and A/AV/AT for the RT analysis) as the within-subjects factors, the order of the stimulation (left PMv first, right PMv first) as a between-subjects factor, and age as a continuous quantitative between-subjects co-variable. Our results demonstrate that multimodal integration is relatively preserved in aging, becoming slower but not less accurate. Importantly, we found a significant linear negative relationship between hemispheric difference and age in the auditory modality, i.e., with increasing age, hemispheric differences declined. Interestingly, no such difference occurred in the bimodal modalities. This suggests a larger recruitment of the right PMv to support auditory speech processes in elderly adults, possibly as a consequence of a reduced auditory acuity with age, or a de-differentiation of the phonemic categories. In contrast, the absence of an age effect in the bimodal conditions suggests that multisensory processing remains stable throughout adulthood. Together, these results demonstrate that multisensory integration mechanisms are, at least in part, maintained with age despite a decline in auditory acuity, and demonstrate the feasibility of using rTMS in healthy elderly adults to study speech and language processes. Acknowledgment: This study was supported by research funds from the European Research Council to J-L.S., by a grant from la Région Rhône-Alpes to A.T., and by an infrastructure grant from the Canadian Foundation for Innovation, to P.T., who also holds a Career Awards from the “Fonds de Recherche du Québec- Santé” (FRQS).
Document type :
Poster communications
Liste complète des métadonnées

https://hal.archives-ouvertes.fr/hal-02074942
Contributor : Avril Treille <>
Submitted on : Thursday, March 21, 2019 - 9:39:15 AM
Last modification on : Friday, April 5, 2019 - 9:18:49 AM

File

Poster_SNL-TMS_printed.pdf
Files produced by the author(s)

Identifiers

  • HAL Id : hal-02074942, version 1

Collections

Citation

Avril Treille, Marc Sato, Jean-Luc Schwartz, Coriandre Vilain, Pascale Tremblay. The role of the premotor cortex in multisensory speech perception throughout adulthood: a rTMS study. 8th Annual Meeting of the Society for the Neurobiology of Language (SNL 2016), Aug 2016, London, United Kingdom. ⟨hal-02074942⟩

Share

Metrics

Record views

8

Files downloads

4