Learning Perception and attention enable us to deal with the present moment. Adaptation also requires learning from experience to improve our behavior in the future. Individual learning experiences are central in shaping us as individuals and generating our separate personalities, desires, likes, dislikes, and skills.
Learning and Prediction
After considerable investigation, behavioral scientists now have a good grasp of fundamental principles of learning, such as how animals and people learn relations among events in their environment and how they learn the effects of their behavior on that environment. Progress has been particularly striking in the understanding of "classical conditioning," the process through which organisms come to associate simple events with one another. This fundamental form of learning is critical for adaptive behavior. Many organisms, including humans, depend upon relatively innocuous signals to warn them of impending significant events. Survival may well depend on identifying those signals accurately. We now know that organisms behave as if they are sophisticated statistical evaluators of information, selecting for association those stimulus events that predict the presence or absence of other significant events.
The current view of conditioning is based on the intuitively simple idea that organisms learn more effectively from unexpected than expected events. The point is well illustrated by a powerful phenomenon known as "blocking." Consider, for example, a situation in which two signals, a tone and a light, jointly precede some important event for an animal, such as an electric shock. If the animal had previously encountered only the tone as a warning signal for shock, when it appears together with the light as a warning signal, the animal treats the light as redundant and uninformative. As a result, it will fail to associate light with shock and will not react appropriately if subsequently only the light is presented. In other words, the prior association of the tone with shock will block learning of the light-shock association.
Experimental studies of blocking have revealed that animals are very sophisticated in detecting and analyzing environmental cues. They also suggest that animals develop relatively complex internal representations of the world. The implications of this work for humans remain to be explored. By clarifying how certain environmental stimuli and situations elicit or suppress undesirable behavior, such as drug abuse, future studies may lead to new approaches for treatment and prevention.
Conditioning and Addiction
Some of the complex effects of addictive drugs follow conditioning principles. For example, researchers have shown that the development of one form of drug tolerance (an addict's need to consume increasingly large quantities of a drug to achieve the original effect) occurs in part through classical conditioning. This process is reasonably well worked out for morphine, and there is increasing evidence for the involvement of conditioning in some consequences of abusing alcohol.
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