Phonological Processing, Visuospatial Skills, and Pattern Understanding in Chinese Developmental Dyscalculia

A number of previous studies have identified cognitive deficits in developmental dyscalculia (DD). Yet, most of these studies were in alphabetic languages, whereas few of them examined Chinese DD. Here, we conducted a study aiming to determine the cognitive factors associated with DD in Chinese children. Five candidate cognitive factors of DD—phonological retrieval, phonological awareness, visual–spatial attention, spatial thinking, and pattern understanding—were studied in the present study. A total of 904 Chinese children aged between 8 and 11 years participated in this study. From the sample, 97 children were identified with DD through tests of arithmetic ability, and 93 age and IQ–matched typically developing children were selected as controls. Logistic regression analysis revealed that phonological retrieval, pattern understanding, visual–spatial attention, and phonological awareness significantly predicted DD, whereas spatial thinking failed to do so. Results of logistic relative weights analysis showed that all five factors explained statistically significant amounts of variance in arithmetic scores. Phonological retrieval had the most influence on DD, followed by pattern understanding, visual–spatial attention, phonological awareness, and spatial thinking. These findings have important clinical implications for diagnosis and intervention of Chinese DD.

Is There a Causal Link between the Left Lateralization of Language and Other Brain Asymmetries? A Review of Data Gathered in Patients with Focal Brain Lesions

This review evaluated if the hypothesis of a causal link between the left lateralization of language and other brain asymmetries could be supported by a careful review of data gathered in patients with unilateral brain lesions. In a short introduction a distinction was made between brain activities that could: (a) benefit from the shaping influences of language (such as the capacity to solve non-verbal cognitive tasks and the increased levels of consciousness and of intentionality); (b) be incompatible with the properties and the shaping activities of language (e.g., the relations between language and the automatic orienting of visual-spatial attention or between cognition and emotion) and (c) be more represented on the right hemisphere due to competition for cortical space. The correspondence between predictions based on the theoretical impact of language on other brain functions and data obtained in patients with lesions of the right and left hemisphere was then assessed. The reviewed data suggest that different kinds of hemispheric asymmetries observed in patients with unilateral brain lesions could be subsumed by common mechanisms, more or less directly linked to the left lateralization of language.

Impaired ability in visual-spatial attention in Chinese children with developmental dyslexia

Many studies demonstrated that alphabetic language speaking children with developmental dyslexia had a deficit in visual-spatial attention, especially in rapid orienting of the attentional spotlight. Chinese, as a logographic language, is characterized as highly visual-spatial complexity. To date, few studies explored the visual-spatial attention of Chinese children with developmental dyslexia. The present study examined the visual-spatial attention of Chinese children with developmental dyslexia using the visual search task. The results showed that Chinese children with developmental dyslexia had poor performances in conjunction search, indicating that they had a deficit in the rapid orienting of visual-spatial attention. Meanwhile, only the conjunction search was a significant predictor of Chinese characters reading when other variables were controlled. These results indicated that Chinese dyslexic children had a deficit in visual-spatial attention, and visual-spatial attention played a special role in Chinese reading development.

The visual encoding of graspable unfamiliar objects

We explored by eye-tracking the visual encoding modalities of participants (N = 20) involved in a free-observation task in which three repetitions of ten unfamiliar graspable objects were administered. Then, we analysed the temporal allocation (t = 1500ms) of visual-spatial attention to objects’ manipulation (i.e., the part aimed at grasping the object) and functional (i.e., the part aimed at recognizing the function and identity of the object) areas. We found a reversed quadratic trend in the way participants visually explored the objects. Within the first 750ms, participants tended to shift their gaze on the functional areas while decreasing their attention on the manipulation areas. Then, participants reversed this trend, decreasing their visual-spatial attention to the functional areas while relatively increasing fixations to the manipulation areas. Crucially, the global amount of visual-spatial attention for objects’ functional areas significantly decreased as an effect of stimuli repetition while remaining stable for the manipulation areas, thus indicating stimulus familiarity effects. These findings support the action reappraisal theoretical approach, which considers object processing and tool use as abilities emerging from the integration among semantic, technical/mechanical, and sensorimotor knowledge.