Transparent fish ‘to aid brain research’

Photo: S.Siva Saravanan

Scientists claim to have found a new way to activate or deactivate areas of the human brain, using light-sensitive brain cells of transparent fish.

An international team, led by Queensland University, has been able to turn on and off neurons responsible for how humans move their bodies by using the natural transparency of young zebrafish.

In fact, the scientists are working with light sensitive proteins which, when expressed in these neurons, causes them to be activated or inactivated by light.

“There are a couple of reasons why we study zebrafish. One is that certain parts of their brain and spinal cord are arranged similarly to those in humans. Secondly, zebrafish are transparent when they are very young, so we can look at structures inside of them, while they are alive and intact,” team leader Dr Ethan Scott said.

In their research, published in the ‘ Nature ’ journal, the scientists demonstrated how light can be used to stimulate specific neurons that led to spontaneous swimming behaviour in the zebrafish.

“The aim was to develop transgenic tools that they used in their study to allow for the expression of various light sensitive proteins in specific neurons.

“In the long run such research should provide insight into how the healthy brain produces certain behaviours, and how these processes go wrong in patients with mental disorders.

“In the next 10 years the challenge will be to keep track of all the tools that are being developed and use these wisely to address the functions of behavioural circuits,” Dr Scott said.