Vladimir Hachinski is a Canadian neurologist, clinical neuroscientist and Distinguished University Professor in the Department of Clinical Neurological Sciences at the Schulich School of Medicine and Dentistry at Western University. He is also a Senior Scientist at London's Robarts Research Institute. His research pertains in the greatest part to stroke and dementia, their interactions, and their joint prevention through integral brain health promotion. He and John W. Norris helped to establish the world's first successful acute stroke unit at Sunnybrook Hospital in Toronto, and, by extension, helped establish stroke units as the standard of care for stroke patients worldwide. He discovered that the control of the heart by the brain is asymmetric, the fight/flight (sympathetic) response being controlled by the right hemisphere and the rest and digest (parasympathetic) response being controlled by the left hemisphere and damage to one key component (the insula) can lead to heart rhythm irregularities and sudden death. This discovery has added fundamental knowledge to how the brain controls the heart and how to prevent sudden death.

Hachinski has held many prominent positions in the global neurology community, including editor-in-chief of the journal Stroke (the leading publication in the field), president of the World Federation of Neurology, and founder of World Brain Alliance. He is a Fellow of the Royal Society of Canada (FRSC) and the Canadian Academy of Health Sciences (FCAHS), a Member of the Orders of Ontario and Canada, the Medical Hall of Fame and the recipient of several national and international awards and recognitions for his research, mentorship, and advocacy in stroke, dementia, public health and healthy aging.

Hachinski was born in Zhytomyr, Ukraine, the eldest of three children. He moved with his family first to Germany and then to Caripito, Venezuela as a child. The family moved to Port Perry, Ontario, Canada thereafter. He graduated from Port Perry High School a year later at the top of his class.

Hachinski received his MD in 1966 from the University of Toronto, and completed his residency in internal medicine and neurology in Toronto and Montreal, followed by a neurophysiology fellowship in Toronto. He received his formal accreditation in neurology as a Fellow of the Royal College of Physicians and Surgeons of Canada (FRCPC) in 1972. From 1973-74, a research fellowship with the Ontario Department of Health brought him to a cerebrovascular laboratory at the National Hospital for Nervous Diseases in London, England, and then to the Department of Clinical Physiology at Bispebjerg Hospital in Copenhagen, Denmark.

Following this, he returned to Toronto to take a staff position in the Department of Neurosciences at Sunnybrook Medical Centre, where he and Dr. John W. Norris established the MacLachlan Stroke Unit, Canada's first acute stroke unit. Hachinski remained at Sunnybrook until 1980, when he moved to London, Ontario to act as a neurology consultant for its major health centres: University Hospital, Victoria Hospital, St. Joseph's Hospital, and the London Psychiatric Hospital. He was hired concurrently as a professor at Western University (then called the University of Western Ontario). During this time (and until 1990), he also acted as Director of the Investigative Stroke Unit at London's University Hospital.

In 1987, he earned a Master of Science degree from McMaster University in Hamilton, Ontario, studying in the Department of Epidemiology and Biostatistics with a focus on design, measurement, and evaluation. The University of London's highest earned degree, Doctor of Science (in Hachinski's case, in medicine), was conferred upon him in 1988 for his "contributions to migraine, stroke, and dementia."

At the beginning of Hachinski's career, the view prevailed that most dementias were caused by hardening of brain arteries (cerebral atherosclerosis). The hypothesis was that a slow strangulation of the brain's blood supply leads to neuronal death and dementia. Hachinski showed in 1975 that, when the dementia was through brain artery disease, most were from "multi-infarct dementias" (his concept) — caused by multiple, small, often symptomless strokes. His term "vascular cognitive impairment" would later be widely adopted to describe the vascular component that occurs in most major dementias. This is an important concept since stroke doubles the risk of dementia and strokes are treatable and preventable. Some dementias are as well. He has offered an explanation for the origin of some of these lesions and associated symptoms through his concept of the ambibaric brain. He postulates that the brain has two complementary blood pressure systems, one high and one low and disturbances in each lead to different types of preventable lesions.

The hardening of the arteries explanation spawned a whole industry of brain vessel "vasodilators". He showed that "vasodilators" were not only expensive but useless. He also developed the "Hachinski Ischemic Score" that continues to be widely used to identify the vascular cognitive impairment, a treatable and preventable component of dementia. Identifying the vascular component is tremendously important for patient prognosis, as treating the vascular causes of dementias can mitigate their effects. The score is cited in the medical literature about once every ten days, and has been validated and optimized for use in clinical practice.