The researchers can pinpoint activity by observing how much oxygen various brain regions are using. (sciencenewsforstudents.org)
Catecholaminergic neurons containing GABA - like and / or glutamic acid decarboxylase - like immunoreactivities in various brain regions of the rat (cmbn.no)
The technique is similar to the electrical probe stimulation that researchers have been using to identify the function of various brain regions, but the shocks often trigger epileptic seizures in sensitive patients. (sciencemag.org)