- B.A. in Cognitive Science and Psychology, Amherst College
- M.A. in Mathematics, Boston University
- Ph.D. in Neurobiology, Harvard University
I was born in the state of Kerala, India and immigrated to the U.S. as a young child. I grew up in the Washington, D.C. metropolitan area and have spent most of my adult life in Massachusetts, where all of my post-secondary education took place.
I have a long-standing interest in the neural dynamics underlying sensory processing, sleep, and learning and memory. To investigate these dynamics I use a combination of computational modeling, signal processing techniques, and both invasive and noninvasive experimental methods of recording brain activity.
In graduate work in the laboratories of Dr. Matthew Wilson (MIT) and Dr. Emery Brown (Harvard Medical School/MIT), I collected electrophysiological recordings from the hippocampus and somatosensory cortex of rats during active behavior and sleep in order to gain insight into general sleep physiology and the role of sleep physiological activity in memory consolidation. In postdoctoral work with Dr. Nancy Kopell (Boston University), I constructed biophysically realistic computational models to account for the pathological occurrence of alpha activity during slow wave sleep. This led to additional work modeling alpha activity during stimulus processing and in anesthetic states. For my postdoctoral work I also examined intracranial data (both electrocorticography (ECoG) and depth electrode data) from epileptic patients to determine the role of sleep oscillations in memory consolidation during both rapid eye movement (REM) sleep and slow wave sleep (SWS). This work led to the discovery of a candidate mechanism for emotional and procedural motor memory consolidation during REM sleep.
- Research Interests: Computational modeling, brain oscillatory dynamics in health and disease, development of stimulation and pharmacological therapies for brain disorders, brain machine interface (BMI), sleep and memory consolidation, sleep and emotional regulation, learning and memory, mental imagery, sleep and epilepsy, Parkinson’s disease, schizophrenia, and posttraumatic stress disorder (PTSD).
- We investigate neural dynamics during active behavior and during off-line states, such as sleep, using a combination of computational modeling, signal processing techniques, and both invasive and non-invasive techniques for recording neural activity. The basic science knowledge gathered from these investigations are leveraged to understand how memories are instantiated in the brain, to gain insight into how learning occurs during brain machine interface (BMI) tasks, to improve BMI algorithms, and to develop the framework for stimulation and pharmacological therapies for diseases, especially those marked by abnormal neural dynamics during sleep (e.g., post-traumatic sleep disorder (PTSD) and Parkinson’s disease).
- Lab Website: Neural Dynamics and Neural Engineering Lab
- Vijayan S, Lepage KQ, Kopell NJ, Cash SS (2017). Frontal beta-theta network during REM sleep. eLife, 6:e18894.
- Vijayan S, Klerman EB, Adler GK, Kopell NJ (2015). Thalamic mechanisms underlying alpha-delta sleep with implications for fibromyalgia. Journal of Neurophysiology, 114, 1923-1930.
- Lepage KQ and Vijayan S (2015). A time series model of phase amplitude cross frequency coupling and comparison of spectral characteristics with neural data. BioMed Research International, 1-8.
- Pittman-Polletta BR, Kocsis B, Vijayan S, Whittington MA, Kopell NJ (2015). Brain rhythms connect impaired inhibition to altered cognition in schizophrenia, Biological Psychiatry, 77, 1020-1030.
- Ahmed OJ*, Vijayan S* (2014). The roles of sleep-wake states and brain rhythms in epileptic seizure onset. Journal of Neuroscience, 34, 7395-7.
- Vijayan S, Ching S, Purdon PL, Brown EN, Kopell NJ (2013). Biophysical modeling of alpha rhythms during halothane-induced unconsciousness. Int. IEEE EMBS Conf. Neural Engineering, 1104-1107.
- Vijayan S*, Ching S*, Purdon PL, Brown EN, Kopell NJ (2013). Thalamocortical mechanisms for the anteriorization of alpha rhythms during propofol-induced unconsciousness. Journal of Neuroscience, 33, 11070-5.
- Vijayan S and Kopell NJ (2012). Thalamic model of awake alpha oscillations and implications for stimulus processing. PNAS, 109, 18553-8.
- Ching S, Purdon PL, Vijayan S, Kopell NJ, Brown EN (2012). A neurophysiological-metabolic model for burst suppression. PNAS, 109, 3095-100.
- Chen Z, Vijayan S, Ching S, Hale G, Flores, FJ, Wilson MA, Brown EN (2011). Assessing neuronal interactions of cell assemblies during general anesthesia. Conf. Proc. IEEE Eng. Med. Biol. Soc., 4175-8.
- Vijayan S, Hale GJ, Moore CI, Brown EN, Wilson MA (2010). Activity in the barrel cortex during active behavior and sleep. Journal of Neurophysiology, 103, 2074-2084.
- Chen Z, Vijayan S, Wilson MA, Barbieri R, Brown EN (2009). Discrete- and continuous-time probabilistic models and algorithms for inferring neuronal UP/DOWN states. Neural Computation, 21, 1797-1862.
- Caplan D, Vijayan S, Kuperberg G, West C, Waters G, Greve D, Dale AM (2001). Vascular response to syntactic processing: event-related fMRI study of relative clauses. Human Brain Mapping, 15, 26-38.
- Marcus GF, Vijayan S, Bandi Rao S, Vishton PM (1999). Rule learning by seven-month-old infants. Science, 283, 77-80.
* Denotes equal contribution
For a full list of Dr. Vijayan's publications, visit PubMed.