13 August 2009

Semantic Brain Organization Innate

Functional MRIs of the people show that people's brains are hard wired to store knowledge about ideas with certain meanings, such as knowledge living things and knowledge about non-living things, in particular parts of the brain. At any rate, this is at least true with respect to ideas that are identified by words or pictures.

These locations within the brain, previously associated with vision and assumed to be based upon shape, are the same for sighted people and people who have been blind all their lives. In other words, the human brain has a build in set of file cabinets into which to put ideas, even though the knowledge comes after birth and is different in detail between different people.

This is in accord with previous studies in developmental psychology and linguistics that have suggested that certain grammatical concepts and rudimentary math concepts to be hard wired in the brain. Even two year olds who cannot string grammatical sentences together themselves and know only a modest number of words, for example, notice when nouns and verbs are used in the wrong places.

The notion that there is a semantic core to all languages and inherent in the human mind, dates back to Plato and is more ambitious than mere grammatical hard wiring. Few semantic elements have been shown to be natural in humans (instinctive fear triggers that horror movies play upon are the exception that proves the rule), even though this kind of instinctive, ancestral memory is common in many species.

This information suggests that there may be a lot more to the humanity that unites us than a mere blank slate filled by experience and culture. We may be united by a common taxonomy of ideas.

This also suggests, however, that there may be inherent hard wired limitations on the sorts of thoughts that humans are capable of having.

In the same vein, people have innate intuitive assumptions about the laws of physics that do not include phenomena like those of quantum mechanics, general relativity and special relativity that are distinct only at scales that are beyond the realm of human experience in the absence of advanced laboratory instrumentation. We can learn the equations and teach ourselves these rules, but they don't come naturally.


Michael Malak said...

This sciencenews writeup masks the plasticity of the brain that you hint at at the end of your comments.

People who were born with the entire brain missing except a thin layer around their cranium have gone on to lead normal lives.

It would be interesting to see how the distinction between living and non-living occurs when much of the brain is missing.

JayDenver said...

Not only is the universe stranger than we imagine, it is stranger than we can imagine. -- Sir Arthur Eddington.

Andrew Oh-Willeke said...

@ JayDenver . . . precisely.

@ Michael Malak . . . good point. Those cases raise all sorts of fascinating questions.