A study has shown that simply massaging a single whisker can prevent strokes from occurring in rats. While it's unclear what this might mean for humans, the study does suggest that this could be well worth testing out.

When a single whisker was mechanically stimulated (stroked) for five minutes, within one hour of when the artery was first blocked, none of the rats suffered a stroke. In other words, this method was 100% effective at preventing stroke.

In the study, researchers blocked blood flow in the main cerebral artery of rats. Left alone, these rats all later suffered strokes. But when a single whisker was mechanically stimulated (stroked) for five minutes, within one hour of when the artery was first blocked, none of the rats suffered a stroke. In other words, this method was 100% effective at preventing stroke. Stimulation given two hours post-blockage prevented stroke in six of eight rats tested. But when the stimulation was given three or more hours after the artery was blocked, no protection was seen. In fact, stimulation three hours after the blockage led to even larger strokes.

Imaging of the rats' brains revealed that this protection occurred because other arteries expanded and increased their blood flow to the affected area of the brain. This compensated for the loss of blood flow in the main artery and prevented a stroke from occurring.

The time frame found by the researchers at the University of California, Irvine, is similar to that found for the drug tPA in human strokes. tPA helps chemically dissolve a blood clot that caused a stroke, restoring lost blood flow to the affected area of the brain. But it is only useful if administered within three hours of the stroke. The earlier it is given, the likelier patients are to recover from the stroke.

Unlike humans, rats are literally led by their noses. The whiskers, which are located nearby, are a major rat sense organ. Because of this, there are a large number of nerve cells leading from the skin surrounding the whiskers to the rat cortex. In humans, other sensitive body parts are wired directly to the cortex, including the hands, face and lips.

People believed to be suffering a stroke are advised to lie still in a quiet environment. The researchers suggest that a good massage, listening to a favorite song or otherwise stimulating the right nerve areas might work better.

There is currently no evidence that any of this is relevant to humans. But as a neuroscientist not associated with the study put it, it would be criminal not to test this possibility out in controlled human studies. Designing these studies may prove puzzling, since it's not possible to accurately predict when a person will suffer a stroke.

The researchers are attempting to find physicians or EMTs willing to try the technique on patients with early stroke symptoms.

An article detailing the study was published June 23, 2010 by the journal PLoS ONE and is freely available.