Individual differences in children’s global motion sensitivity correlate with TBSS-based measures of the superior longitudinal fasciculus

Abstract

Reduced global motion sensitivity, relative to global static form sensitivity, has been found in children with many neurodevelopmental disorders, leading to the “dorsal stream vulnerability” hypothesis (Braddick et al, Neuropsychologia, 2003). Individual differences in typically developing children’s global motion thresholds have been shown to be associated with variations in specific parietal cortical areas (Braddick et al, J Cog Neuro, 2016). Here, in 125 children aged 5–12 years, we relate individual differences in global motion and form coherence thresholds to fractional anisotropy (FA) in the superior longitudinal fasciculus (SLF), a major fiber tract communicating between parietal lobe and anterior cortical areas. We find a positive correlation between FA of the right SLF and individual children’s sensitivity to global motion coherence, while FA of the left SLF shows a negative correlation. Further analysis of parietal cortical area data shows that this is also asymmetrical, showing a stronger association with global motion sensitivity in the left hemisphere. None of these associations hold for an analogous measure of global form sensitivity. We conclude that a complex pattern of structural asymmetry, including the parietal lobe and the superior longitudinal fasciculus, is specifically linked to the development of sensitivity to global visual motion. This pattern suggests that individual differences in motion sensitivity are primarily linked to parietal brain areas interacting with frontal systems in making decisions on integrated motion signals, rather than in the extra-striate visual areas that perform the initial integration. The basis of motion processing deficits in neurodevelopmental disorders may depend on these same structures.

Crystallized and fluid intelligence are predicted by microstructure of specific white‐matter tracts

“…This result, at first sight, is counterintuitive if FA reflects "white-matter integrity" or "increased speed" of neural activity along the corresponding fiber tracts. Similar lack of concordance with the "myelin integrity" hypothesis was found by Braddick et al (2017) for the correlation of individual children's sensitivity to global motion coherence with the FA of the left SLF. Hoeft et al (2007) also showed increased FA of SLF was associated with poor visuospatial abilities in Williams' syndrome, which argues against the white-matter FA identification.…”

The role of diffusion MRI in neuroscience

“…For example, as summarized in Figure , variation in bimanual co‐ordination skills correlates with variation in FA in the body of the corpus callosum, a white matter area that contains transcallosal pathways between primary and supplementary motor areas . Similar effects have been found in a wide range of sensory, motor and cognitive domains including, for example, vision, audition, motor skills and language, literacy, emotion and motivation, visuo‐spatial, memory and executive function, and individual characteristics, such as creativity, musical skills and personality …”

The Davida Teller Award Lecture, 2016

“…A further step in the arguments comes from analyzing fiber tracts in the PLING cohort of children (Braddick, Atkinson, Akshoomoff et al, 2016). Our analysis focused on the superior longitudinal fasciculus (SLF), the major pathway carrying two-way information between the parietal and frontal lobes, and one associated with functions of visuo-spatial attention (e.g., Bennett, Motes, Rao, & Rypma, 2012; Mayer & Vuong, 2014; Chechlacz, Gillebert, Vangkilde, Petersen, & Humphreys, 2015).…”

“…Fractional anisotropy (FA)—a measure of how far the tract is organized so that water molecules diffuse most easily along the direction of the tract—revealed a statistical relationship with the children's motion coherence sensitivity. This relationship showed a striking asymmetry (Braddick, Atkinson, Akshoomoff et al, 2016). For the right SLF, FA was high in the children with high global motion sensitivity, but on the left, the reverse relationship was found.…”

“…(A) Effect size map of the association between children's global motion sensitivity and relative local cortical expansion in the left hemisphere (Braddick et al, 2016). Red and yellow indicate increasing t values for positive associations, especially around the intraparietal sulcus (IPS); blue indicates negative associations, especially in the occipital lobe.…”