Jerome has gone in for a psychiatric assessment. He tells the clinician that he has been hearing voices and he feels like he is losing touch with reality. The clinician would classify these abnormal behaviors using:

A group of rats was exposed to the uncontrollable stress associated with being forced to swim for 15 minutes in cold water from which they cannot escape. What did researchers notice when they observed these animals?

a. Most rats were immune to the effects of the stress. b. The rats' depression was reduced by the high level of physical activity. c. The stress caused a form of brain damage that first led to motor retardation and then death. d. The rats that exhibited symptoms similar to depression had altered neurotransmitter levels.

A store owner is trying to determine how much advertising increases her overall profit. If she conducted an experiment, amount of advertising would be the ________ variable

a. dependent b. independent c. operational d. confounding