Understanding how the brain generates behaviour is one of the ultimate goals of neuroscience – and one of its most difficult questions. In recent years, researchers have developed a number of methods that enable them to remotely control specified groups of neurons and to probe the workings of neuronal circuits.
The most powerful of these is a method called optogenetics, which enables researchers to switch populations of related neurons on or off on a millisecond-by-millisecond timescale with pulses of laser light. Another recently developed method, called chemogenetics, uses engineered proteins that are activated by designer drugs and can be targeted to specific cell types.
Although powerful, both of these methods have drawbacks. Optogenetics
is invasive, requiring insertion of optical fibres that deliver the
light pulses into the brain and, furthermore, the extent to which the
light penetrates the dense brain tissue is severely limited.
Chemogenetic approaches overcome both of these limitations, but
typically induce biochemical reactions that take several seconds to
activate nerve cells....<<<Read The Full Article Here>>>...
