On February 12, Vijay Mohan K. Namboodiri, a native of Thrissur, defended his PhD at the Department of Neuroscience, Johns Hopkins University School of Medicine. A crowd of fellow students and professors witnessed the defense. Thousands of miles away, members of his family sat glued to Skype to hear him tell his story. His findings have been published in ‘Neuron,’ an internationally-renowned journal of neuroscience, on March 26.
In his thesis, he investigated the question of how human beings perceive the passage of time and include it in their decisions. “If I ask you to wait for a second, you may easily do it. But have you wondered how your brain measures the second and tells you that it is over? I addressed this question in my experiments. Voltage signals from the brain should be recorded to understand how the brain measures a second. I focussed on experiments with rats for which such recording techniques are well-established,” he says.
In his experiment, he flashed a light on rats and trained them to wait for a second. He did so by rewarding the rats the longer they waited, that is, up to a second. So, if the rat waited one second, it would get twice the reward than it did if it waited half a second. “Intelligent as rats are, they learn to wait a second in this task. Once the rats were trained, I recorded their brain activity. My aim was to understand how their brains told rats that a second was over,” he says.
The brain recordings told the researcher an unexpected story. He found that an area of the brain that was supposed to process the light flash was also involved in instructing the animal that a second was up. “There is a notion that the brain is programmed in such a way that different areas do different things; one region is involved in sensing light, another in measuring time and yet another in making the movement to indicate that time is up. My observations challenge this view. I find that different areas of the brain are inexorably interlinked, more so than they were previously thought to be,” he says.
Son of K.K. Kesavan Namboodiri, former Superintendent of Central Excise, and P.B. Sreedevi, Professor of Physics in Sree Kerala Varma College, Mr. Vijay Mohan Namboodiri is an alumnus of Kendriya Vidyalaya, Thrissur, and IIT, Mumbai. He is currently working as a post-doctoral researcher in the laboratory of Prof. Garret Stuber at the University of North Carolina, Chapel Hill. Here, he strives to understand the role of dopaminergic neurons in normal and impaired decision-making.