Low doses of the active ingredient in marijuana appear to stop some forms of brain damage in mice, an Israeli researcher has found.

Tiny amounts of THC may protect rodent brains after injuries from seizures, lack of oxygen or toxic drug exposure, according to the Los Angeles Times. Josef Sarne of Tel Aviv University injected mice with a low dose of THC, either before or after the rodents were exposed to brain trauma. The amount of THC they received was 1,000 to 10,000 times less than that found in a conventional marijuana cigarette. A second group of mice experienced brain injury without receiving THC, Sarne reported in Behavioural Brain Research and Experimental Brain Research.

When the mice were examined three to seven weeks after injury, those that received THC performed better on tests that measured learning and memory. They also had greater amounts of brain-protecting chemicals.

THC is thought to ignite biochemical processes that protect brain cells, and preserve brain function, the article notes. Sarne said one day THC might be given before a procedure that could result in brain injury, such as heart-lung machines used in open heart surgery, which may require an interruption of blood flow to the brain.

In a news release, Sarne said THC may cause minute damage to the brain that builds resistance and triggers protective measures in the face of a much more severe injury. “The low dosage of THC is crucial to initiating this process without causing too much initial damage,” he said.