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Asymmetric brains may enhance sensory information processing, according to a new study.

Researchers found that fish that have symmetric brains are less able to process information about sights and smells. While its long been known that the left and right sides of the brain have slightly different roles in cognition and regulating behavior, it's still unclear whether these asymmetries affect brain functioning.

However, the latest study on zebrafish reveals that brain asymmetry can have significant consequences on sensory processing, which could lead to cognitive dysfunction.

"We don't know whether asymmetries actually matter for the efficient functioning of the brain. For instance, if your brain was symmetric, would it work any less well than it normally does?" Professor Steve Wilson, senior author of the study from the UCL Department of Cell & Developmental Biology, said in a news release.

"This is potentially an important issue as brain-imaging studies in various neurological conditions have shown alterations in normally asymmetric patterns of neuronal activity," he added.

Researchers used two-photon high-resolution microscopy to image the activity of individual neurons in a part of the brain called the habenulae in larval zebrafish. Scientists then engineered fish in which habenular asymmetry was reversed and fish with double-right and double-left sided habenulae.

The findings revealed that the functional properties of the habenular neurons were reversed when the direction of the brain asymmetry was turned around.  However, double-left and double-right sided brains almost completely lacked habenular responsiveness to smell or light respectively.

"These results show that loss of brain asymmetry can have significant consequences upon sensory processing and circuit function," said researcher Dr. Elena Dreosti.

The findings are published in the journal Current Biology.