Brain activation during phonological and semantic processing of Chinese characters in deaf signers

Abstract

Previous studies found altered brain function in deaf individuals reading alphabetic orthographies. However, it is not known whether similar alterations of brain function are characteristic of non-alphabetic writing systems and whether alterations are specific to certain kinds of lexical tasks. Here we examined differences in brain activation between Chinese congenitally deaf individuals (CD) and hearing controls (HC) during character reading tasks requiring phonological and semantic judgments. For both tasks, we found that CD showed less activation than HC in left inferior frontal gyrus, but greater activation in several right hemisphere regions including inferior frontal gyrus, angular gyrus, and inferior temporal gyrus. Although many group differences were similar across tasks, greater activation in right middle frontal gyrus was more pronounced for the rhyming compared to the meaning task. Finally, within the deaf individuals better performance on the rhyming task was associated with less activation in right inferior parietal lobule and angular gyrus. Our results in Chinese CD are broadly consistent with previous studies in alphabetic languages suggesting greater engagement of inferior frontal gyrus and inferior parietal cortex for reading that is largely independent of task, with the exception of right middle frontal gyrus for phonological processing. The brain behavior correlations potentially indicate that CD that more efficiently use the right hemisphere are better readers.

The neural underpinnings of reading skill in deaf adults

“…However, these differences were only evident in region of interest (ROI) analyses -not in the whole-brain analysis. Li, Peng, Lui, Booth, and Ding (2014) found a similar (and statistically more robust) pattern for deaf Chinese readers making semantic relatedness judgments to pairs of Chinese characters. The deaf readers (fluent users of Chinese Sign Language) showed greater activation in right frontal cortex (as well as in the right inferior parietal lobule) and reduced activation in left IFG compared to hearing readers (reading ability was not assessed).…”

Orthographic and phonological activation in Hong Kong deaf readers: An eye-tracking study

“…For example, deaf readers can take in more information in the parafoveal visual range (i.e., the parafovea, which encompasses one to two words beyond the fixated word for most readers—see Vasilev & Angele, 2017) and process it more efficiently than hearing readers (Bélanger et al, 2012, 2013, 2018; Yan et al, 2015). Despite having limited access to spoken phonology, there is evidence that deaf readers activate phonological code during silent reading (Gutierrez-Sigut et al, 2017; Hanson & Lichtenstein, 1990; Li et al, 2014; Yan et al, 2015). Elliott et al (2012) suggested that those phonological units, rather than being based on acoustic information, are based on mouth-shape-based units acquired through lip-reading.…”

The Nebraska Educator Volume 4: 2017

“…Thus, because of the informational challenges to the cerebral cortex, non-native Chinese speakers are more likely to feel mental exhaustion when reading and comprehending Chinese Some researchers find comprehension is a little different in Chinese rhyme readings. Li et al (2014) detected that when comprehending Chinese rhyme readings, the right middle frontal gyrus in the cortex is more active. The right middle frontal gyrus, as Japee et al (2015) explain, influences the control of reorienting attention from external factors.…”