An MRI of the human brain. Photo: Wikimedia Commons.

JNS.org – A new collaborative study conducted by Israeli and American researchers has uncovered how sleep deprivation negatively affects brain activity.

The study — published in the Nature Medicine biomedical research journal — was led by researchers at Israel’s Tel Aviv University (TAU) in cooperation with the University of California-Los Angeles (UCLA) and the University of Wisconsin-Madison.

Researchers found that losing sleep causes neural activity in the brain’s temporal lobe to slow down, triggering visual impairment and memory loss. They observed that neurons in the brain rest, essentially taking a nap, after being adversely affected by slow brainwaves.

“When we’re sleep-deprived, a local intrusion of sleep-like waves disrupts normal brain activity while we’re performing tasks,” said Yuval Nir, of TAU’s Sackler Faculty of Medicine and Sagol School of Neuroscience, who directed the study.

Throughout the study, researchers logged the brain activity of 12 epilepsy patients who had previously shown little or no response to drug interventions at UCLA.

In order to record neural activity, the patients were hospitalized for a week and had electrodes implanted to identify the area of the brain where seizures originate. The patients were kept awake for a whole night in order to accelerate the investigation.

As the brain became more sleep-deprived, specific areas of the brain “caught some sleep,” said Nir. “Most of the brain was up and running, but temporal lobe neurons happened to be in slumber,” causing various behavioral lapses, he said.