Turning Our Words into Actions.

Linguists have been trying to map language (and all it's cognitive aspects) in the brain. We now know (generally) where speech is produced, where grammar comes into the picture, where written language is decoded, etc.

Recently, linguists have been looking for meaning in the brain. For example, you just heard the word 'cat', but is your concept of 'cat' stored in the same place as your perception of someone saying the word 'cat'? The short answer is 'no'. Most studies of this nature (trying to localize word meaning in the brain) have focused on concrete, visual nouns. In a study by Hauk, Johnsrude, and Pavermuller (2004), the question of word localization is applied to action words with very interesting results.

Their experiment was elegant. They chose three categories of action words, each related to a different region of the body (specifically face/tongue words like "lick", arm words, "throw", and leg words, "kick"). They selected 50 words for each category and then had their subjects read them (silently), all while in an fMRI brain scanning machine. Turns out that the (non-language-specific) areas of the brain that are activated by DOING the physical action (of the word) overlap significantly with the brain areas activated be just READING the word. Let me run that by you again. Reading an action word like "throw" activates the arm-related area of the motor cortex as well as normal language areas.

Now, no experiment should be taken too seriously, but this data implies that the meaning of a word (at least the meaning of an action word) lies somewhere between understanding the word and doing the action.

In My Mind's Ear

I was talking with a friend today who told me to "listen to something with my mind's eye." This made me wonder whether or not there is such a thing as a 'mind's ear'. Upon further discussion an reflection, we concluded that there must be a 'mind's ear', at least metaphorically, because otherwise it could never get too loud to hear yourself think. Now, I like working out kinks in common metaphors as much as the next person, but this conclusion of ours lead to another, more complicated question: How can there be a listener (the mind's ear) and a speaker (the self) within a single (sane) mind, what areas of the self/cognition are responsible for hearing and speaking, and how is all this synthesized into a cohesive whole? These are essentially questions that lie at the heart of Cognitive Science. Any thoughts on the subject?

Dreaming = Normal?

Department of Redundancy Department

Science asks questions. When science gets an answer it's easy, for the media especially, though scientists have been guilty as well, to think that it is the answer. More and more evidence indicates that many biological systems, especially the human nervous system, are naturally and necessarily redundant. We can regulate our body temperature by storing fat or sweating, we can write a letter with a pencil or a computer, etc. Though redundancy seems to be an inefficient use of energy, it makes a system much more stable and durable.

When a person is forming complex words, for example, "walked", there are two language mechanisms available; you can simply memorize the world "walked" as a single unit, or you can consciously construct it from "walk" and "-ed." Recent studies show that rather than using one mechanism all the time, people tend to use a specific mechanism depending on the situation. People tend to memorize high frequency words like "walked" and construct rare words, like "balked." An interesting side note, estrogen is a memory aid, so women use the memorization method for more words (on average) than men.

Many of the new findings in neuroscience may make more sense if we try to see how they might fit in a redundant system, rather than what they do on their own.

This portion of CogSigh brought to you, in part, by Michael Ullman, a Professor of Neuroscience at Georgetown University in his article "More is Sometimes More."