As a person gets older, they will experience an increase in which of the following abilities?

B.F. Skinner believed that to change behavior, change the reinforcer.

a. true b. false

Last month Pam was giddy, impulsive, and talkative; this month she is sad, silent, and almost motionless. What is the most likely diagnosis?

a) bipolar disorder b) anxiety disorder c) severe depression d) somatoform disorder