Peter J. Siekmeier is an Assistant Professor of Psychiatry at Harvard Medical School and an Attending Psychiatrist at McLean Hospital, where he specializes in bipolar and psychotic disorders. He earned a BSE in Civil Engineering and Operations Research from Princeton University and an MS from MIT, before receiving his MD from Yale School of Medicine.

He completed his psychiatric residency at Massachusetts General Hospital and McLean Hospital, Harvard-affiliated programs. Following residency, he became a NIMH Postdoctoral Clinical Research Fellow in computational neuroscience before joining the faculty at Harvard Medical School. In 2006, he founded the Laboratory for Computational Neuroscience at McLean.

His research focuses on biophysically realistic, cellular-level computational models of psychiatric illness and the development of novel, clinically relevant EEG biomarkers for schizophrenia and other serious mental illnesses. His work has been supported by multiple NIMH and foundation grants and published across clinical and neuroscience journals. He also served as the inaugural Web Editor of the Archives of General Psychiatry.