It's eerie to look inside the brain of a heavy cocaine user.
Blood flow is sluggish and abnormal compared to the brain of a non-user.
Such an abnormality may underlie memory loss, learning problems, attention deficits, and even strokes. With the aid of advanced types of imaging equipment, Harvard University researchers have become the first to actually see why the flow is slow. In experiments carried out at McLean Hospital in Belmont, they watched blood vessels narrow as volunteers took different amounts of the drug. That has never been shown before, and we think that many episodes of such narrowing can lead to brain dysfunction or damage. Other experiments reveal that even thinking about cocaine can change cerebral blood flow.