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Summary: Applications of Classical Conditioning

Classical conditioning is a very basic form of learning. It can be demonstrated even with single nerve cells.

Conditional release of transmitter antagonists may underlie the phenom­enon of drug tolerance. This helps to explain why overdoses are more common after a period of abstinence, or when the drug is taken in an unfamiliar setting. Under those conditions, conditional release of antagonists is less likely and tolerance is reduced.

Classical conditioning has also been shown to affect responses of the immune system. This is important because it implies that learned responses to significant stimuli might affect health.

A CER or conditional emotional re­sponse is a learned response to cues that occur before an emotionally powerful event. CERs can result from pleasant or unpleasant emotions.

CERs involving very unpleasant emotions sometimes motivate people to seek therapy. Like other forms of classical conditioning, the responses are largely involuntary and resistant to conscious control.

CERs can be pleasant, for example, when odors awaken fond memories. Or they can involve illness.

Taste aversion is a special form of CER that occurs when a person gets sick after eating a particular food. Even if the illness is known to be caused by a virus, not by the food, the taste aversion can be strong and durable.

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