Search Abstracts | Symposia | Slide Sessions | Poster Sessions
Graded Neural Signatures of Holistic Processing for Faces, Chinese Characters, and Lines in Primary School Poor Readers: An fMRI Alignment Paradigm Study
Poster Session C, Thursday, October 1, 10:45 am - 12:45 pm, Wangari Maathai
This poster is part of the Sandbox Series.
Tian Jiang1, Kristin Langohr1, Nizhuan Wang1, Ricky Van Yio Tso2, Wai Ting Siok1; 1Department of Language Science and Technology, The Hong Kong Polytechnic University, 2Faculty of Education, The University of Hong Kong
Introduction. Holistic processing, defined as encoding a visual stimulus as an integrated whole rather than as discrete parts, is a well-established expertise marker for face recognition and has been proposed to extend to other visually learned categories, including Chinese characters. Yet direct neuroimaging evidence for the graded holistic hierarchy and its potential disruption in poor readers, remains lacking. The present study used fMRI with an alignment paradigm to test whether faces, Chinese characters, and line patterns elicit graded holistic processing responses in the brains of school-age poor readers, and whether reading-network regions are differentially recruited by aligned character configurations. Methods. Ten primary school children (Nine boys, Grades 2–5, Mean age= 9.02 years, all poor readers) underwent 3T fMRI. In each trial, participants judged whether two simultaneously presented stimuli (face pairs, Chinese character pairs, or line pattern pairs) were identical or different. Stimuli were presented in either aligned (holistic configuration) or misaligned (halves spatially offset) arrangements across six blocked conditions. A simple same-different line judgment task is included as baseline condition. BOLD data was processed using the fMRIflows automated pipeline (motion correction, MNI152 normalisation, 10.5 mm smoothing) and modelled with a seven-condition GLM. First-level contrast images were submitted to group one-sample t-tests (N = 10; threshold: p < 0.05 uncorrected). Results. A clear neural gradient emerged for the alignment effect: faces produced the largest response, followed by Chinese characters and line patterns. For faces, the alignment effect (face_aligned > face_misaligned) was strongly lateralised to bilateral inferior and middle temporal gyri and right temporal fusiform cortex posterior division, encompassing the fusiform face area (FFA). For Chinese characters, activation relative to baseline (characters_aligned > baseline) revealed significant recruitment of left temporal fusiform cortex and posterior division. Critically, while the overall dominance of a whole-brain misaligned > aligned response for characters indicates that poor readers expend substantially greater neural resources when holistic character configurations are disrupted, a left angular gyrus cluster nonetheless exhibited a reliable alignment advantage. The angular gyrus is a key node of the reading network, linking VWFA orthographic representations to phonological and semantic systems. The angular gyrus’s selective response to aligned over misaligned character pairs suggests that reading-relevant circuitry retains sensitivity to holistic character configuration even in poor readers. Line patterns showed no reading-network involvement, with alignment effects confined to occipital regions. Conclusion. These findings provide neuroimaging evidence for a graded holistic processing hierarchy , faces > Chinese characters > lines, in primary school poor readers. Co-activation of the VWFA and left angular gyrus for aligned Chinese characters implicates the core reading network in holistic orthographic processing, suggesting that the circuitry linking visual form analysis to language remains sensitive to whole-character configurations even reading fluency is not yet established. The atypical whole-brain dominance of the misaligned response for characters, however, indicates that holistic character processing is not robustly generalised in the poor readers. These results highlight a dissociation between reading-network nodes and broader cortical systems in their sensitivity to character alignment, with implications for understanding the neural basis of reading difficulties.
Topic Areas: Reading, Disorders: Developmental