Brain stimulation may boost memory: study

Someday, the process might be used to make a neuroprosthetic device, or thinking cap, that people could turn on when they need to remember new information, or it may even help people with dementia restore their memories.

But those possibilities, while intriguing, are far off in the future, said researchers at the University of California Los Angeles whose study on seven epilepsy patients appeared in the New England Journal of Medicine.

“Losing our ability to remember recent events and form new memories is one of the most dreaded afflictions of the human condition,” said senior author Itzhak Fried, professor of neurosurgery at the David Geffen School of Medicine at UCLA.

“Our preliminary results provide evidence supporting a possible mechanism for enhancing memory, particularly as people age or suffer from early dementia,” he said.

“At the same time, we studied a small sample of patients, so our results should be interpreted with caution.”

Using patients who already had electrodes implanted into their brains to track the origin of epileptic seizures, the researchers studied the effect of nerve stimulation in a part of the brain called the entorhinal cortex.

The entorhinal cortex is considered the doorway to the hippocampus, the part of the brain where memories are formed and stored.

“The entorhinal cortex is the golden gate to the brain’s memory mainframe,” said Fried.

“Every visual and sensory experience that we eventually commit to memory funnels through that doorway to the hippocampus.”

Patients played a video game in which they were driving a taxi to deliver riders to particular places in town, and they showed improved recall when the entorhinal cortex was stimulated.

“When we stimulated the nerve fibers in the patients’ entorhinal cortex during learning, they later recognized landmarks and navigated the routes more quickly,” said Fried.

“They even learned to take shortcuts, reflecting improved spatial memory.”

More research is needed to determine if deep-brain stimulation could boost other forms of recall such as verbal and autobiographical memories.

The study was funded by grants from the National Institute of Neurological Disorders and Stroke and the Dana Foundation which supports brain research. (AFP)