FRIDAY, 11 SEPTEMBER 2020The near magical ability of each portion of the neocortex to encode one aspect of the full range of perceptual experiences is well known, but few recognise the unseen role of the broad bands of association fibers connecting the neocortex. Consider, for instance, their importance in language. Each word is but a label, linking its perception or generation to the contexts in which it might apply. Association fibers are uniquely suited for this, as they form numerous, yet localised connections to allow the faithful, long distance sharing of cortical activity, contextualising the information that they represent. Without association fibers, the brain’s capacity for language is diminished. Disrupt the arcuate fasciculus, and gone is the synchronisation between meaning and pronunciation, preventing fluent speech. Disrupt the inferior longitudinal fasciculus, and individual concepts are dissociated from their underlying form, colour, and shape, creating an inability to label reality in concrete or abstract terms. Finally, disrupt the occipitofrontal fasciculus, and you separate the abstract features that underlie language from their underlying somatosensory and syntactic representations, completely disrupting language.
Clifford Sia is the website developer at BlueSci.