A study revealed that nerve cells widely distributed in the brain respond to specific aspects of memory and may be more specialized than previously thought. George Ojemann, professor of neurological surgery, published his research in the January 2002 issue of Nature Neuroscience.
The study involved patients with epilepsy who were awake during surgery to remove parts of the brain responsible for seizures. Researchers asked the patients to respond to requests to recall words, names of pictures and sounds. Four microelectrodes in the patient's brain recorded the electrical activity as the neurons communicated with other cells. The microelectrodes identified impulses from pools of neurons as patients were asked questions that measure stages of memory. Separate activity of individual neurons was deduced based on the shape of their individual discharges.
Researchers were able to identify the behavior of 105 neurons at 57 sites in 26 patients. Previously Ojemann's teams largest sample was 31 neurons.
This study was supported by a grant from the National Institute of Neurological Disorders and Stroke, and was a collaborative project with David Corina, professor of psychology.