Australian National University (ANU) researchers have developed a new device that could potentially unravel the mysteries of the left and right brain by measuring ear temperature.
The device, which may also have medical applications, offers scientists a cost-effective way of testing which side of the brain is active when performing different tasks.
Scientists know that, depending on what kind of work the brain is doing, one side is likely to be more active — broadly speaking, language skills, for example, are handled by the left side of the brain and spatial questions are dealt with in the right — but brain scans can be an expensive research tool.
The new device, developed by psychologists Mr Nicolas Cherbuin and Dr Cobie Brinkman, measures the temperature inside a subject’s ears to work out which side of the brain is busier.
“If an area of the brain is more active it needs more blood, which flows up the carotid artery on either side of neck,” Mr Cherbuin said. “This blood is shared between the brain and the inner ear, so by measuring the ear temperature we can work out which side of the brain is more active.
“Because the blood flowing to the brain is cooler than blood already in the brain, a decrease in ear temperature indicates increased blood flow and therefore increased activity on that side of the brain.”
The test, which uses highly sensitive infra red detectors placed in the ear, was developed using two tasks, one that is known to be handled by the left side of the brain (a language task involving rhyming words) and another that scientists know is carried out on the right (which involved mentally constructing three-dimensional cubes after seeing an ‘unfolded’ two-dimensional one).
Minute fluctuations (of less than 0.1 degree) in ear temperature were found to be a highly effective indicator of brain activity.