| 1. |
- Andin, Josefine, 1979-, et al.
(author)
-
fMRI Evidence of Magnitude Manipulation during Numerical Order Processing in Congenitally Deaf Signers
- 2018
-
In: Neural Plasticity. - : HINDAWI LTD. - 2090-5904 .- 1687-5443.
-
Journal article (peer-reviewed)abstract
- Congenital deafness is often compensated by early sign language use leading to typical language development with corresponding neural underpinnings. However, deaf individuals are frequently reported to have poorer numerical abilities than hearing individuals and it is not known whether the underlying neuronal networks differ between groups. In the present study, adult deaf signers and hearing nonsigners performed a digit and letter order tasks, during functional magnetic resonance imaging. We found the neuronal networks recruited in the two tasks to be generally similar across groups, with significant activation in the dorsal visual stream for the letter order task, suggesting letter identification and position encoding. For the digit order task, no significant activation was found for either of the two groups. Region of interest analyses on parietal numerical processing regions revealed different patterns of activation across groups. Importantly, deaf signers showed significant activation in the right horizontal portion of the intraparietal sulcus for the digit order task, suggesting engagement of magnitude manipulation during numerical order processing in this group.
|
|
| 2. |
- Andin, Josefine, 1979-, et al.
(author)
-
The neural basis of arithmetic and phonology in deaf signing individuals
- 2019
-
In: Language, Cognition and Neuroscience. - : ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD. - 2327-3798 .- 2327-3801. ; 34:7, s. 813-825
-
Journal article (peer-reviewed)abstract
- Deafness is generally associated with poor mental arithmetic, possibly due to neuronal differences in arithmetic processing across language modalities. Here, we investigated for the first time the neuronal networks supporting arithmetic processing in adult deaf signers. Deaf signing adults and hearing non-signing peers performed arithmetic and phonological tasks during fMRI scanning. At whole brain level, activation patterns were similar across groups. Region of interest analyses showed that although both groups activated phonological processing regions in the left inferior frontal gyrus to a similar extent during both phonological and multiplication tasks, deaf signers showed significantly more activation in the right horizontal portion of the inferior parietal sulcus. This region is associated with magnitude manipulation along the mental number line. This pattern of results suggests that deaf signers rely more on magnitude manipulation than hearing non-signers during multiplication, but that phonological involvement does not differ significantly between groups.Abbreviations: AAL: Automated Anatomy Labelling; fMRI: functional magnetic resonance imaging; HIPS: horizontal portion of the intraparietal sulcus; lAG: left angular gyrus; lIFG: left inferior frontal gyrus; rHIPS: right horizontal portion of the intraparietal sulcus
|
|
| 3. |
- Cardin, Velia, et al.
(author)
-
The Organization of Working Memory Networks is Shaped by Early Sensory Experience
- 2018
-
In: Cerebral Cortex. - : OXFORD UNIV PRESS INC. - 1047-3211 .- 1460-2199. ; 28:10, s. 3540-3554
-
Journal article (peer-reviewed)abstract
- Early deafness results in crossmodal reorganization of the superior temporal cortex (STC). Here, we investigated the effect of deafness on cognitive processing. Specifically, we studied the reorganization, due to deafness and sign language (SL) knowledge, of linguistic and nonlinguistic visual working memory (WM). We conducted an fMRI experiment in groups that differed in their hearing status and SL knowledge: deaf native signers, and hearing native signers, hearing nonsigners. Participants performed a 2-back WM task and a control task. Stimuli were signs from British Sign Language (BSL) or moving nonsense objects in the form of point-light displays. We found characteristic WM activations in fronto-parietal regions in all groups. However, deaf participants also recruited bilateral posterior STC during the WM task, independently of the linguistic content of the stimuli, and showed less activation in fronto-parietal regions. Resting-state connectivity analysis showed increased connectivity between frontal regions and STC in deaf compared to hearing individuals. WM for signs did not elicit differential activations, suggesting that SL WM does not rely on modality-specific linguistic processing. These findings suggest that WM networks are reorganized due to early deafness, and that the organization of cognitive networks is shaped by the nature of the sensory inputs available during development.
|
|
