Tag Archives: Disconnection syndrome

New developmental prosopagnosia research hot off the web

While I was looking at the website of the Journal of Neuroscience I found this interesting and important free access article:

Michael Lohse, Lucia Garrido, Jon Driver, Raymond J. Dolan, Bradley C. Duchaine, and Nicholas Furl Effective Connectivity from Early Visual Cortex to Posterior Occipitotemporal Face Areas Supports Face Selectivity and Predicts Developmental Prosopagnosia. Journal of Neuroscience. 30 March 2016, 36(13): 3821-3828; doi: 10.1523/JNEUROSCI.3621-15.2016

http://www.jneurosci.org/content/36/13/3821.full.pdf+html

What is face selectivity? I’ll have to do a bit of study on that.

For me the findings of this study are not surprising, even though there are apparently new ideas in this paper about face selectivity and developmental prosopagnosia (DP). As a synaesthete who also appears to be a “super-recognizer” of faces from a family in which precociously high levels of literacy skills are found, I firmly believe that the common thread that runs through synaesthesia, literacy skills and face memory is good to exceptional connectivity inside the brain. My ideas are supported by research that has linked synaesthesia with hyper-connectivity, and has linked dyslexia and DP with problems with connectivity.

Backs up my ideas

I was reading through back issues of New Scientist, and I found a brief article about the work of researcher Sophie Scott and other researchers, written by Simon Makin. This article is about one theory of dyslexia winning out over another. The theory that seems to be the most compatible with recent research findings is the theory of dyslexia as a “disconnection syndrome” resulting from poor connections between particular regions in the brain. The competing theory of dyslexia as a disability stemming from subtle problems with hearing speech sounds is apparently being debunked.

What relevance does this have for my theories and ideas about synaesthesia and visual perception? The theory of dyslexia as a problem of hypoconnectivity in the brain is not new, but it is nice to see it winning favour among researchers because it fits well with observations that I made years ago at this blog that there seems to be a cluster of phenomena linked to grapheme-colour synaesthesia in my family, and some of those phenomena are exceptional gifts in specific areas of literacy, including spelling, writing and reading, identified by professional and independent testing for selective school entry, as well as precocious reading and one case of superior face memory (a super-recognizer). A few years ago at this blog I contrasted this combination of literacy and visual memory gifts found along with synaesthesia (a sensory-perception phenomenon that researchers have found is caused by greater than average connectivity in the brain) with what I have argued is the opposite condition of a type of dementia named Benson’s syndrome which has loss of ability to read, spell and recognize faces as symptoms of atrophy at the back of the brain, the general area of the brain that I theorized is hyper-developed or hyper-connected in some members of my family, including myself. Although dyslexia isn’t the same thing as Benson’s I think the evidence about dyslexia fits in nicely with my ideas. If a reading disability is caused by hypoconnectivity in the brain, that does seem to support my idea that reading superiority can be caused by the same difference that makes a brain a synaesthete brain, that difference being hyperconnectivity. The hypoconnected dyslexic looks like the opposite of the hyperconnected synaesthete who has always been ahead of his or her peers in reading and writing, and perhaps even taught him or herself to read before grade one.