Researchers at the Yerkes National Primate Research Center, Emory University, have identified a feature in the brain that is unique to human language. I found this article interesting because we all know that language is exclusive to humans, and we discuss this fact in class, however, the findings in this study provide evidence of connectivity in brain regions for this uniqueness when compared to brain regions of chimpanzees, and sheds light on an evolution aspect of how human language has evolved. Therefore, I found this article appropriate for this class to grasp a better understanding for language being specific to humans.
The study that was conducted was the first to use diffusion tensor imaging (DTI), which is a non-invasive imaging technique that was used to compare the human brain structures to those of chimpanzees. James Riling, a researcher at Yerkes, looked at the arcuate fasciculus, which is a pathway that connects brain regions involved in human language. The researchers then examine the size and pathway of the arcuate fasciculus in human, rhesus macaques, and chimpanzees. They found that the human arcuate fasciculus had a larger and more widespread projection to areas in the middle temporal lobe – which is involved in analyzing the meanings of words. Furthermore, they not only found that the human brain evolved larger language areas, but has also evolved a network of fibers to connect those regions that were not found in the rhesus macaques and chimpanzees. This ultimately supports human’s superior language capabilities.
This study is important because it was the first use of the DTI, which before, researchers lacked non-invasive methods to study brain connectivity directly. And, according to Yerkes researcher Todd Preuss “DTI now makes it possible to understand how evolution changed the wiring of the human brain to enable us to think, act, and speak like humans.”