Tag Archives: Stephen Wiltshire

Left anterior temporal lobe versus right anterior temporal lobe – does one really need to be autistic to have excellent visual memory?

I’m not a paid researcher and I don’t work in a university, so when I discover new things that help to make sense of my unusual visual processing experiences (various visual types of synaesthesia, IMLM, scene-concept synaesthesia, super-recognition, The Strange Phenomenon etc) it is often by accident as I go about my usual lifestyle. It was only an accident many years ago that I found out that synaesthesia is a neuropsychological phenomenon recognized by science, when I was reading about another subject that interested me at the time, and synaesthesia was mentioned in passing and described in a quaint footnote. The other day I was at my local library looking thru a pile of New Scientist magazines to select issues that I hadn’t read. I didn’t realise that I’d borrowed one from 2010, but when I opened it up at an article about research that has demonstrated how visual memory can be enhanced I wasn’t sorry that I took that old issue off the shelf.

This article, which sadly is behind a paywall, but can probably be easily accessed in hard-copy thru any good public library, is not about face memory or face recognition, but I think it is still an interesting clue about what might be different about my brain. As I’ve written before in articles that I’ve published here, it is my belief that there is a general enhancement in the functioning of the right temporal lobe areas of my brain, which includes the fusiform gyrus on the right, which includes the fusiform face area on the right. I guess my fusiform gyrus on the left is probably working well also. The thing that makes this article so interesting to me is that it seems to show that at least part of the left and right temporal lobes work in opposition to each other, and when the activity of the right is boosted while the activity of the left is inhibited the result is an enhancement of visual memory. Could a naturally-occuring skewed relationship between left and right in the temporal lobes be an explanation for my test scores consistent with me being a super-recognizer of faces? Has some bright-spark researcher at a uni somewhere done a version of the transcranial direct current stimulation (tDCS) study discussed in this article, exploring face memory? If I was a researcher that is what I’d be looking at.

The other aspect of this article that I find striking is the view of autism that it presents. Science magazines are full of stories about autism research, and as a reader of these publications I’ve read my fair share of such stories, but I’ve never before read an article depicting autism as a natural enhancement in visual memory. I guess such a benefit of autism might be implied in the many books and articles that have been published about autistic savants who create realistic art (Stephen Wiltshire and Gregory Blackstock would be some fine examples), and no doubt an enhanced visual memory could also be behind the many autistic people who have superior navigation ability, but what I’ve generally found is that most books and articles about autism don’t delve very far into brain-based explanations of autistic enhancement of visual memory. As I recall, behavioural explanations are far more common than neuropsychological explanations – autistic people’s special visual abilities are often dismissively described as being the result of obsessive, repetitive learning. Clearly there is more to it than that. In this article by Sujata Gupta in New Scientist autism is explicitly linked with enhancement in visual memory. So does one need to be autistic to have superior visual memory? And how does this all relate to face memory? What is the relationship between autism and super-recognition, if any? I’m not going to hold my breath waiting for researchers to tackle these questions.

Gupta, Sujata Little brain zap, big memory boost. New Scientist. August 14th 2010. Issue 2773 p.16.

Online reference: Skull electrodes give memory a boost. New Scientist. 13 August 2010 by Sujata Gupta Magazine issue 2773. http://www.newscientist.com/article/mg20727733.900-skull-electrodes-give-memory-a-boost.html

It appears that the study described in the above article has not been published in a journal yet, but below is the details of a paper about a similar study co-authored by Richard Chi:

Paulo S. Boggio, Felipe Fregni, Claudia Valasek, Sophie Ellwood, Richard Chi, Jason Gallate, Alvaro Pascual-Leone, and Allan Snyder
Temporal Lobe Cortical Electrical Stimulation during the Encoding and Retrieval Phase Reduces False Memories.
PLoS ONE. 2009; 4(3): e4959. Published online 2009 March 25. doi: 10.1371/journal.pone.0004959 PMCID: PMC2655647

Pretty as a landscape

I’ve just been having a quick look at the abstract of a journal paper about agnosia for scenes, which is apparently an inability to recognize and learn scenes lacking salient landmarks. It seems to be related to prosopagnosia, which is an inability to recognize faces. The link between these disabilities is easily understood when one thinks with one’s mind’s eye. A face is like a landscape. Have you ever heard of the term “pretty as a picture”? One could take that literally. Some noses are hills, and others are more like mountains. Some people have noses like a great dividing range, a great long thing continuous with the brow.

If there really is a close relationship between prosopagnosia and agnosia for scenes, then it seems clear that agnosia for scenes is not much to do with landmarks. It is surely about the whole picture, the entire landscape, a thing that wraps around one, a reality that one can almost feel through one’s back and upper arms. I’m sure there is something unusual about the way I percieve faces and the way I experience scenes. I believe I enjoy “encoding” both types of things more than most people. When I am a tourist it is all about discovering new vistas, experiencing and remembering new places. I am the ultimate rubberneck, and I don’t much care if it looks a bit odd or a bit unsophisticated. When I visit a home that I have never seen before, I can’t help looking around a lot, even though I have little interest in interior decoration. If your home has the same floorplan as another home that I’ve been inside, it won’t take long for me to detect that.

My memory for places does have limits. In case you are wondering if I am a savant who can draw incredibly detailed scenes from memory, like Stephen Wiltshire and other autistic savants, you will be disappionted. I think I was pretty good at art when I was a high school student. My art teacher seemed to take a special interest in my work, even though I was never the star of the class. I tried to draw what I actually saw, which other students didn’t seem to be doing much, and I tried to be a bit original, but I wasn’t a human camera, and art has never been a major interest of mine.

Mendez, MF, Cherrier, MM Agnosia for scenes in topographagnosia. Neuropsychologia. 2003;41(10):1387-95. http://www.ncbi.nlm.nih.gov/pubmed/12757910