Effects of laser guided by optic fiber into rat brain on conditioned avoidance response and brain chemistry

Low power lasers were guided by optic fibers into the rat caudate nucleus or frontal cortex, during conditioned avoidance response (CAR) training. The changes in striatal monoamine and amino acid concentrations were subsequently determined. Of six training groups tested, only the experimental group with helium-neon laser radiation to the caudate nucleus exhibited the formation of CAR and an increase of unconditioned leg contractions. The striatal concentrations of dopamine (DA) and norepinephrine (NE) were increased simultaneously in the group.