Michael Halassa

Michael Halassa, MD, PhD is a Professor at the Fralin Biomedical Research Institute at Virginia Tech, with appointments in Psychiatry and Behavioral Medicine at the Virginia Tech Carilion School of Medicine and in Biomedical Engineering at the College of Engineering. His laboratory identified the first non-relay function for the thalamus: the control of task-relevant cortical representations and effective connectivity. Specifically, and by performing research across mice, tree shrews, and humans, the lab showed that the mediodorsal thalamus compresses high-dimensional cortical activity into low-dimensional contextual states, decomposes task uncertainty into separable components, and enables rapid reconfiguration of cortical networks to match changing task demands. This framework, developed through a combination of circuit physiology, computational modeling, and human neuroimaging, has positioned thalamocortical interactions as a central organizing principle of how the brain implements cognitive operations.

Laboratory research

The lab’s work has focused on the mediodorsal thalamus and its role in regulating task-relevant cortical dynamics and effective connectivity in the prefrontal cortex. Using well-parametrized behavioral tasks combined with neural recordings and temporally precise circuit manipulations, the lab showed a role for the mediodorsal thalamus in sustaining prefrontal activity patterns during attention, switching prefrontal representations underlying cognitive flexibility, and regulating prefrontal signal-to-noise during decision-making under uncertainty. That work has been published in leading journals.

The lab has also developed the tree shrew (Tupaia belangeri) as a model system for cognition, enabling richer behavioral repertoires than rodents while maintaining circuit-level readout and control. This platform supports collaborative work spanning computational modeling, human cognitive neuroscience, and translational psychiatry.

Translational research

Dr. Halassa’s translational program, algorithmic circuit psychiatry, treats psychiatric symptoms as alterations in specific neural algorithms. The goal is to measure those algorithms precisely enough to stratify patients, map them onto circuits, and target them with the right interventions. Dr. Halassa is particularly interested in understanding negative symptoms in schizophrenia, and his lab has recently identified potential tasks that track these symptoms, some of which can be back-translated into animal models, creating a fully integrated basic-to-clinical research pipeline. This is congruent with the rapidly changing landscape of treatments for psychotic illnesses, some of which are uniquely capable of addressing these symptoms.

Training and positions

Dr. Halassa completed medical school at the University of Jordan and obtained his doctoral degree in neuroscience at the University of Pennsylvania in 2009. He completed a postdoctoral fellowship with Matt Wilson at MIT while pursuing psychiatry residency at Massachusetts General Hospital/Harvard Medical School, completing both in 2014. He started his laboratory at the NYU Neuroscience Institute, moved to MIT where he was promoted to Associate Professor in 2020, and subsequently served as Professor and Director of Translational Research in the Department of Neuroscience at Tufts University before joining Virginia Tech.

Recognition

His work has been recognized by the Vilcek Prize for Creative Promise in the Biomedical Sciences, the Takeda/New York Academy of Sciences Innovator Award, and fellowships and awards from the Pew, Klingenstein, Feldstein, Simons, Sloan, Kavli, Max Planck, and Brain and Behavior Foundations. He has placed multiple trainees as junior faculty in leading institutions such as Penn, RIKEN, Stony Brook, and others.