" the physiology of the central nervous system. In a pamphlet entitled “ Reflexes of the Brain,” published in Russian in 1863, he attempted to represent the activities of the cerebral hemispheres as reflex—that is to say, as determined. Thoughts he regarded as reflexes in which the effector path was inhibited, while great outbursts of passion he regarded as exaggerated reflexes with a wide irradiation of excitation. "

― Ivan Pavlov , Conditioned Reflexes