WMCA, Word-List Multimodal Cortical Atlas, a new model of the neural organization of Word-List

The GIN has developed a new atlas of cortical areas of the neural organization of Word-List processing common to production, listening and reading tasks. This will be particularly interesting for assessing the neuroanatomical changes induced by language pathology, more particularly speech impairment such as dysarthria and apraxia and for cohort studies looking for the genetic bases of word-list regions.

In line with the SENSAAS atlas (Labache et al, 2019), WMCA was developed from functional Magnetic Resonance Imaging (fMRI) obtained during both task-induced and resting-state acquisitions in 144 right-handed subjects from the BIL&GIN database (a database dedicated to the study of hemispheric specialization, Mazoyer et al, 2016).

Aim of the study

We aimed at identifying plurimodal large-scale networks common to producing, listening to and reading word lists based on the combined analyses of task-induced activation and resting-state intrinsic connectivity.

How

In the first step, we identified the regions in each hemisphere showing joint activation and joint asymmetry during the three tasks. Fourteen left homotopic regions of interest (hROIs) and 7 right hROIs met this criterion.

In a second step, we computed the resting-state BOLD temporal correlations across these 21 hROIs and conducted a hierarchical cluster analysis to unravel their network organization. Two networks were identified, including the WORD-LIST_CORE network that aggregated 14 motor, premotor and phonemic areas in the left hemisphere plus the right STS that corresponded to the posterior human voice area (pHVA).

 

Locations of the 21 hROIs. A) Right and left lateral and medial views of the 2 identified networks. WORD-LIST_CORE network: green, and WORD-LIST_CONTROL: pink. B) Intra- and inter-hemispheric correlations at rest across the 21 hROIs.The left motor areas and the right STS are strongly and positively correlated, and they constitute the WORD-LIST_CORE network (green).

 

WORD-LIST_CORE network

The WORD-LIST_CORE network highlighted here makes it possible to propose, for the first time, a model of the neural organization of Word-List processing during production, listening and reading tasks.

This model posits that

(1) action and perception circuits are interdependent and organized in networks, among which a trace of the learning modality is still present in the brain;

(2) the involvement of phonological action–perception circuits, such as the phonological working memory loop, in which articulatory gestures are the central motor units on which word perception, production and reading develop and act according to the motor theory of speech (Liberman and Whalen 2000), as revealed by the recruitment of leftward frontal and precentral areas together with temporo-parietal areas

(3) the involvement of the left SMG with the right STS3 (pHVA), which is a prosodic integrative area, could reflect the intertwining between prosodic and phonemic information.

 

Contact : Isabelle Hesling

 

Complete reference

Hesling, I., Labache, L., Joliot, M., and Tzourio-Mazoyer, N. (2019). Large-scale plurimodal networks common to listening to, producing and reading word lists: an fMRI study combining task-induced activation and intrinsic connectivity in 144 right-handers. Brain Struct Funct 224, 3075–3094. doi: 10.1007/s00429-019-01951-4

Bibliography

Labache, L., Joliot, M., Saracco, J., Jobard, G., Hesling, I., Zago, L., Mellet, E., Petit, L., Crivello, F., Mazoyer, B., et al. (2019). A SENtence Supramodal Areas AtlaS (SENSAAS) based on multiple task-induced activation mapping and graph analysis of intrinsic connectivity in 144 healthy right-handers. Brain Struct Funct 224, 859–882. doi: 10.1007/s00429-018-1810-2

Mazoyer, B., Mellet, E., Perchey, G., Zago, L., Crivello, F., Jobard, G., Tzourio-Mazoyer, N. (2016). BIL&GIN: A neuroimaging, cognitive, behavioral, and genetic database for the study of human brain lateralization. Neuroimage, 124:1225-1231. doi: 10.1016/j.neuroimage.2015.02.071