House of Mind

jtotheizzoe:

Noam Chomsky once wrote:

“As far as we know, possession of human language is associated with a specific type of mental organization, not simply a higher degree of intelligence. There seems to be no substance to the view that human language is simply a more complex instance of something to be found elsewhere in the animal world.”

Human language and its precursors seem to have developed by natural selection, an ever-advancing form of communication based on natural selection and brain size. Are there parts of our DNA that could code for language abilities? A language gene?

Years ago, scientists studied a British family that seemed to have a genetic speech impediment. This peculiar family led to the discovery of the gene FOXP2. Since then, other individuals with varying mutations in this gene have been found, and they all have language impediments.

All land-dwelling vertebrate animals carry this gene, but what does it do? Since it entered animal genomes, it has remained surprisingly unchanged, even after tens of millions of years. Until humans, that is. There’s been a recent acceleration in the evolution of FOXP2 since humans came to be, particularly in two amino acids. 

Recent work with fMRI and biochemistry showed that the protein is important to controlling the fine neuron-to-muscle connections that lead to our ability to make advanced sounds and phonetics. Mice and birds also showed particular vocal changes when their FOXP2 proteins were changed. 

It appears that the human FOXP2 gene allowed our ancestors to grow more advanced neuromuscular connections in the areas that control vocalization. Because of this, we were able to develop more advanced forms of communication to go along with our increased brain size. Our language is far more than just a gene, but we may have found a key ingredient in how it came to be.

For one, I love Chomsky. Second, I too recently found out about the FOXP2 gene. Some of the animal models in which it’s role is being studied (aka singing mice and songbirds) are particularly interesting. I’ll probably post more in depth about it sometime, but here are two reviews for those of you that want to learn more about this: (the first one is free full text)

White, S.A., et a.. 2006. Singing mice, songbirds and more: Models for FOXP2 function and dysfunction in human speech and language. Journal of Neuroscience 26 (41): 10376-9. 

Vargha-Khadem, F. et al. 2005. FOXP2 and the neuroanatomy of speech and language. Nature Reviews Neuroscience. 6 (12): 131-8.

(Source: jtotheizzoe)