Poster Session D, Monday, March 25, 8:00 – 10:00 am, Pacific Concourse
Brain Activations of Categorical Tone Perception in Children with Specific Language Impairment
Huei-Mei Liu1, Feng-Ming Tsao2, Wei-Chin Hsu3, Li-Chun Kuo1; 1National Taiwan Normal University, 2National Taiwan University, 3National Taiwan University of Science and Technology
Individuals with Specific Language Impairment (SLI) are characterized by difficulties in understanding and/or producing language without obvious neurological deficits. The neural basis of underlying speech perception deficits have yet to be specified. The present study investigated the categorical speech perception deficits in children with SLI at behavioral and neural activation level. 22 school-age Mandarin-speaking students with SLI and 22 age-matched controls with typical development (TD) participated. The stimuli were a nine-point synthesized tone continuum of Mandarin /ba2/-/ba4/ syllables (tone 2&4). The identification and discrimination of lexical tones were used to examine the categorization performance. Within-category and across-category pairs with equal acoustic distances were selected to construct the two speech blocks in fMRI experiment. Compared to controls, individuals with SLI showed less accurate in discrimination and shallower categorization slope behaviorally. On the neural level, both groups showed activations in Wernicke's area (BA22), Heschl's gyrus (BA41, BA42), left prefrontal (BA6) and Insula, indicating the involvement of auditory and motor activations in speech perception. The between-group analysis showed when processing within-category speech, TD group exhibited greater activation than SLI group in left BA41, right BA42 and BA6, whereas the SLI group exhibited greater activation in left Insula. For across-category speech processing, SLI group exhibited greater activation than TD group in Broca’s area (BA45), bilateral Temporal Pole (BA38), and left Insula. The correlation analysis showed associations between activation level (BOLD signal change in BA22, BA45, Insula) and speech categorization performance. The results provided the evidence for aberrant speech perception processing of individuals with SLI.
Topic Area: LANGUAGE: Other