Saturday, September 19th, 2009

cluttered speech

I would like to see some neuroscience research as to why nervousness/anxiety seems to cause cluttered speech / stuttering. Does attending to others' perceptions of you use up resources, like a musician who can't keep up with the fast tempo? Does an analogous thing happen with musical performances? Do people improve when they don't have to look at the audience? (I know that many stutterers have no problem singing, probably because it involves no improvisation)

This must be related to speech production being one of those things that isn't 100% deliberate.
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Tuesday, May 5th, 2009

"this brain has a mind of its own"

Marvin Minsky talks about cognition as "society of mind"... which replaces the homunculus with a society of homunculi. The point is to think of the brain as a collection of agents working in parallel, each with a "mind" of its own. Cognition arises from the parts plus their communications with each other.

Some people identify agents with modules, and there are many philosophical-ish debates about what this means (Fodor's "Modularity of Mind", Pinker, Spivey's "Continuous Mind"). One can also wonder how agents/modules relate to functional and anatomical connectivity between brain regions.

Anyway, it looks like multiple levels of the brain do reinforcement learning (by which I mean decision-theoretic reasoning and planning towards the goal of achieving delayed rewards). Although the planning capacity may be shared by different agents, I would suspect that each agent has its own reward function, and thus different goals... which is why "conflict resolution" is a necessary component of cognitive systems.

For example, imagine an addicted person who wants to quit: some agent disagrees with the higher level consciousness. This may boil down to different discount rates: the craver wants to "feel" good right now, whereas the conscious person wants to feel good over the next year. But regardless, it's not clear how one can control the lower levels of the mind.

Achieving self-control: can one align the goals of the higher levels with those of the lower level agents? Are there schools of self-help based on these ideas?



Tangential: Many agents, including many instinctive ones (fear of snakes, sexual attraction), depend on learned high-level percepts (newborns learn to recognize snakes over some time). The fact that we can't turn off these instincts means that we don't have direct control over the higher levels of the visual cortex.
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Friday, November 24th, 2006

"great stuff is usually made within set boundaries"

Stolen from this comment:



What an awesome idea to think about!

Constrained languages make it easier to standardize communication (think semantic web vs. the free web), minimizing errors of interpretation. A familiar movie-plot-structure or song-rhythm tends to put the viewer at ease and confident. At this point, it's easy to switch into "flow"y automatic mode, focusing on the higher-level structure (i.e. the meaning rather than the words). By constantly demanding your attention (though not necessarily your focus), the task puts you in a trance-like state of consciousness.

This is kinda like how driving on a highway can be relaxing.

When the medium is free-form (at least in the time dimension), one's attention is free to shift around, and one is free to spend time on complex planning, etc... it is precisely this freedom that makes anxiety possible.

I would like to look at frontal lobe activation in structured vs unstructured tasks. If my hypothesis is correct (more frontal activation in unstructured tasks), this would explain autistic impairment in the latter.

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Bluegrass seems like a very constrained form. Maybe this is my bias, since it's a style I know very well.

To test this hypothesis using information theory, I would try to show that the relevant features can be compressed quite efficiently.

If we had an MDL program for generating any tune over the space of bluegrass tunes (generating only the relevant features, let's say the kind of information that is in a MIDI file), the input necessary to generate any given tune would be rather small.
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Friday, August 19th, 2005

modeling phonology; declarative vs procedural a false dichotomy

'Foreign accent syndrome' explained . Do you know anyone who sounds foreign even though they're completely local?
I knew a girl in college who sounded like she was from the South, despite the fact that she had spent her whole life in Connecticut. It annoyed her when even the foreign guy (me) noticed. I am of course *not* implying that people in the South are brain-damaged.

It would be very interesting to make cognitive models of speech production (which is harder than perception) for second-language speakers. Why do Indians render [w] as [v], while Brazilians render it as [u]? (both languages have both phonemes)
This research might even help actors.

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By the way, some knowledge is neither declarative nor procedural: for instance the knowledge that recognize a face.
It's not declarative because you don't know how you do it, and you can't pass it on to someone else.
But it's not procedural because it's about perception, not action.
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