She's not there

[aesmael]

A lot of you have probably seen that right-brain/left-brain dancer illusion going round. According to Mo|Neurophilosophy the whole right/left brain thing is nonsense, although from his further writing in that post I formed the impression it is more that certain functions may be processed predominantly in a particular hemisphere, rather than people working mainly from one or the other. Apparently the illusion is more closely related to the way human brains interpret ambiguous images, of which there are many famous examples (famous by appearance at least, I cannot recall the name of a single one).
Bear in mind that I am in no way trained or knowledgeable in this field. If anyone who reads this can add to or correct what I have written, please feel free.

These sentences were also intriguing: "Speech illustrates this, but also shows that nothing is ever so simple when it comes to the brain: in most right-handed people, speech is processed in both hemispheres, but predominantly in the left. In some left-handers, speech is processed either predominantly in the right hemisphere or on both sides."
Being ambidextrous (favouring left), I was naturally curious about the associated distribution of speech processing, so I asked Google Scholar for |ambidextrous speech process|*. One of the articles turned up was this one [PDF], which suggests that five or six ways in which my neurology differs from most people could have a basis in a particular set of genes.
The paper seems mainly geared around generating interest in investigating this terribly convenient idea than presenting conclusions. I remain very doubtful, and the hypothesis presented does not seem to explain lesbianism or bisexuality in women. It also treats transsexuality as an orientation. I do not know if that is standard or a sign of poor scholarship (or both, yes).
The correlations mentioned and referenced are interesting though. Hopefully I can find the time to take a look at them.

Second result seemed promising to be more relevant at first. It turned out to be a book chapter (The motor theory of language, extracted from Studies in Language Origins Volume 2) containing only a brief mention of ambidexterity, that such people were surprisingly found to produce speech faster than either right- or left-handed people as well as "superiority [concerning] certain manual movements" (not specified).

What I found more interesting was the first sentence: " Language is taken to be the capacity of one individual to alter, through structured sound emission, the mental organisation of another individual."
To me this seems incorrect, excluding as it does sign languages and text (music is language, though). Depending on what is meant by mental organisation it may include sounds made by some (many?) other animals too. Would anyone care to nominate an improved version? I came up with "Language is the capacity of one individual to deliberately alter, through structured signals, the mental organisation of another individual", although I am not wedded to it. Especially the word deliberately.

This pdf, apparently a set of lecture notes for a psychology class, says that (contrary to popular belief) information from both eyes and both ears is sent to both hemispheres of the brain. Towards the end (page 6 of 7) there is a figure indicating that people of intermediate handedness have an intermediate level of "Right Hemisphere Language Dominance". This seems to be the answer to my question and all the most promising-looking papers were behind pay walls.

As an aside, here is the abstract of an article claiming chimpanzees also exhibit handedness (predominantly right, like us [it is often my assumption that the hypothetical readers of these posts are human]) I forgot to include the link and do not care to expend the effort to track it down.

Some other posts of interest which turned up in my search for the original article up top: Dave Munger|Cognitive Daily talks briefly about a recent study showing a narrowed gender gap in spatial reasoning after playing a visually demanding video game.
From the same source, more brevity about the stability of 'friends with benefits' relationships. I am not going to read the full article now because I am tired and it is reputedly 75 pages long, but the outcomes reported seem generally more positive than I was expecting before clicking.


*My attempt to mark for colour-blind readers the search string used without suggesting they were contained in quote marks when the search was conducted. Is there a convention for this?

Comments

[freelark.livejournal.com]

Interesting. FWIW I initially saw the dancer spinning in a clockwise direction, despite having been officially diagnosed with a disorder characterized by left brain dominance.