Neural underpinnings of sentence reading in deaf, native sign language users.

The goal of this study was to investigate sentence-level reading circuits in deaf native signers, a unique group of deaf people who are immersed in a fully accessible linguistic environment from birth, and hearing readers. Task-based fMRI, functional connectivity and lateralization analyses were conducted. Both groups exhibited overlapping brain activity in the left-hemispheric perisylvian regions in response to a semantic sentence task. We found increased activity in left occipitotemporal and right frontal and temporal regions in deaf readers. Lateralization analyses did not confirm more rightward asymmetry in deaf individuals. Deaf readers exhibited weaker functional connectivity between inferior frontal and middle temporal gyri and enhanced coupling between temporal and insular cortex. In conclusion, despite the shared functional activity within the semantic reading network across both groups, our results suggest greater reliance on cognitive control processes for deaf readers, possibly resulting in greater effort required to perform the task in this group.

Executive Function in Deaf Native Signing Children.

The aim of this study is twofold: To examine if deafness is invariably associated with deficits in executive function (EF) and to investigate the relationship between sign language proficiency and EF in deaf children of deaf parents with early exposure to a sign language. It is also the first study of EF in children acquiring Polish Sign Language. Even though the mothers of the deaf children (N = 20) had lower levels of education compared with the mothers of a hearing control group, the children performed similarly to their hearing peers (N = 20) on a variety of EF task-based assessments. Only in the Go/No-go task were weaker inhibition skills observed in younger deaf children (6-9 years) compared with hearing peers, and this difference was not seen in older children (10-12 years). Hence, deafness does not necessarily impair EF; however, attentional and inhibition abilities may be acquired via a different route in deaf children. Sign language receptive skills predicted EF in deaf children. In conclusion, we highlight the importance of deaf parenting building the scaffolding for EF in deaf children.