Definition for Stimulus generalization
From Biology Forums Dictionary
In conditioning, stimulus generalization is the tendency for the conditioned stimulus to evoke similar responses after the response has been conditioned. For example, if a child has been conditioned to fear a stuffed white rabbit, it will exhibit fear of objects similar to the conditioned stimulus such as a white toy rat.
In the classic Little Albert experiment, researchers John B. Watson and Rosalie Rayner conditioned a little boy to fear a white rat. The researchers observed that the boy experienced stimulus generalization by showing fear in response to similar stimuli including a dog, a rabbit, a fur coat, a white Santa Claus beard and even Watson's own hair.
Stimulus Generalization and Discrimination
Stimulus generalization can occur in both classical conditioning and operant conditioning. However, a subject can be taught to discriminate between similar stimuli and to only respond to a specific stimulus. For example, imagine that a dog has been trained to run to his owner when he hears a whistle. After the dog has been conditioned, he might respond to a variety sounds that are similar to the whistle. Because the trainer wants the dog to respond only to the specific sound of the whistle, the trainer can work with the animal to teach him to discriminate between different sounds. Eventually, the dog will respond only to the whistle and not to other tones.
In another classic experiment conducted in 1921, researcher Shenger-Krestovnika paired the taste of meat (the unconditioned stimulus) with the sight of a circle. The dogs then learned to salivate (the conditioned response) when they saw the circle. Researchers also observed that the dogs would begin to salivate when presented with an ellipse, which was similar but slightly different that the circle shape. After failing to pair the sight of the ellipse with the taste of meat, the dogs were able to eventually discriminate between the circle and ellipse.