In Milgram's obedience study, 15 percent of the subjects refused to administer any shocks to the "learner."

The fact that you answer the phone only when it rings is an example of the guidance of

behavior by a. negative reinforcement. b. successive approximations. c. generalizing stimuli. d. discriminative stimuli. e. blocking.

Which neurotransmitter may cause neurons to become overexcited, and thus may cause damage if its level is excessive?

a) dopamine b) serotonin c) norepinephrine d) glutamate