Thursday, September 17, 2020
Face-reading is strictly innate
Interesting piece of research in terms of PURPOSE and design.
It's been known for a long time that humans and many other animals have a firm template for perceiving faces and expressions. How firm is this template?
The fusiform face area responds selectively to faces and is causally involved in face perception. How does face-selectivity in the fusiform arise in development, and why does it develop so systematically in the same location across individuals? Preferential cortical responses to faces develop early in infancy, yet evidence is conflicting on the central question of whether visual experience with faces is necessary. Here, we revisit this question by scanning congenitally blind individuals with fMRI while they haptically explored 3D-printed faces and other stimuli. We found robust face-selective responses in the lateral fusiform gyrus of individual blind participants during haptic exploration of stimuli, indicating that neither visual experience with faces nor fovea-biased inputs is necessary for face-selectivity to arise in the lateral fusiform gyrus.The blind subjects were using their fingers to read 3d-printed 'bas relief' pictures of faces. Experience is unlikely. In more 'touchy' cultures, blind people (and especially blind-deaf people) are allowed to use their hands on faces and throats, but not in US. A blind person would know his own face, but wouldn't have an opportunity to pick up expressions from others. Even experience with the printed contour maps is rare. Contour printing was available before the modern 3d stuff; Playboy used to produce a Braille edition with a tactile centerfold. But this form of art was never common even in Braille publications. So this is strictly hard-wired, part of the design and purpose. As with speech/hearing and writing/reading, both ends of the channel had to be matched by design. If faces or face muscles mutated significantly, the fusiform gyrus template wouldn't have worked. Irrelevant alt-history footnote: Contour printing would have been much more common if the Bain tactile scanner had been commercially successful.
Labels: Constants and Variables, Grand Blueprint
¶ 5:01 AM
