Neuroscientists from Massachusetts Institute of Technology (MIT) have found that a gene mutation that happened 50,000 years ago might be the reason why humans are able to understand and produce speech.
The research findings, which were reported on September 15, came from the work of researchers at MIT, as well as several universities in Europe. The scientists determined that the human gene Foxp2 allows for the transformation of new experiences into routine functions. In their research using laboratory mice, they engineered the subjects to express the humanized gene and found that the mice more easily learned to run a maze than regular lab mice.
This suggested that the gene might significantly help people in learning a language, allowing them to transform their experiences, such as hearing a specific word, when they are shown an image that corresponds to the word. This process results in an almost automatic association of words with objects, according to researcher Ann Graybiel, a professor at MIT and a member of the school’s McGovern Institute for Brain Research. This very significant finding was confirmed by the other leading authors of the study, including Wolfgang Enard, who teaches anthropology and human genetics at Ludwig-Maximilian University, and Ulrich Bornschein and Christiane Schreiweis at the Max Planck Institute for Evolutionary Anthropology.
Development of linguistic skills
Although all species of animals are able to communicate with each other, humans are the only ones able to produce and understand language. The scientists believe that Foxp2 is just one of several genes that influence the development of linguistic skills in humans. Their research was inspired when they identified the gene in several members of a family that were severely challenged in speaking and understanding speech. All of these family members were carrying a mutated version of this particular gene.
It is interesting to note that only two amino acids differentiate the Foxp2 gene in humans from its counterpart in laboratory mice. The scientists learned that the protein produced by Foxp2 is a transcription element that works like a switch for other genes. In the case of this particular study, the researchers were able to determine that Foxp2 can “turn on” the genes that regulate the junctions connecting neurons and can “turn off” some neurons for longer periods of time, resulting in what the scientists called “long-term depression.” This is a very important phase wherein a species can learn new undertakings and form memories. The researchers believe that these are changes that help the brain to tune up and adapt to language and speech acquisition.
The group of scientists is now embarking on further research to determine how Foxp2 interacts with other genes, hoping that they will learn more about how it affects language and learning.