Because billions of neurons are packed into our brain, the neuronal circuits that are responsible for controlling our behaviors are by necessity highly intermingled. This tangled web makes it complicated for scientists to determine exactly which circuits do what. Now, using two laboratory techniques pioneered in part at Caltech, Caltech researchers have mapped out the pathways of a set of neurons responsible for the kinds of motor impairments–such as difficulty walking–found in patients with Parkinson’s disease.
The different colors represent pathways involving different cells that instruct diverse behaviors. Using optogenetics and tissue clearing via PACT, Caltech scientists could extract specific pathways for locomotion and reward.
Credit: Ken Chan and Viviana Gradinaru Group at Caltech