The Reporter: June 1996, Vol.7, No.3
Research Notes
Memory Flaw in Parkinson's

Bad timing, rather than nerves, may explain the irregular motions of patients with Parkinson's disease, according to ongoing research by Dr. John Gibbon, director of biopsychology at the New York State Psychiatric Institute and professor of psychology at Columbia. Any body movement involves a timed sequence of motions and "evidence is accumulating that a central problem in Parkinson's is memory for time, a cognitive function in the brain, not a neuromuscular function," says Dr. Gibbon. "Even simple movements require complex temporal sequencing."

Dr. Gibbon presented the research at the annual meeting of the American Association for the Advancement of Science in Baltimore. His work, and that of collaborators, has shown which parts of the brain allow humans and animals to sense intervals of time and why that sense is so important.

Dr. Gibbon, with Chara Malapani, a scientist with the French research organization INSERM U-289 and the H(tm)pital de la Salptrire in Paris, discovered that Parkinson's patients have difficulty estimating and remembering timed intervals. The researchers hypothesize that the jerky motions of Parkinson's may result from a patient's inability to time smooth, fluid movement, creating instead a series of separate, stop-and-go motions.

The work is the first to indicate that damage to the basal ganglia, a region of the brain that coordinates voluntary muscle movements, results in temporal memory deficiencies that may cause the ill-timed motor sequences of Parkinson's.