The peak shift effect is a phenomenon, observed in stimulus generalization, which takes place after discrimination training comprising two stimulants across a typical dimension. An example of the peak shift effect is let's say Amber dated Kyle who had blonde hair and blue eyes. Amber and Kyle ‘s relationship was not good, and Amber found Kyle controlling and possessive. Amber later dates John who has brown hair and brown eyes. Their relationship was perfect, and Amber loved everything about John, but they later broke up. Now whenever Amber goes out she is only interested in guys with brown hair and brown eyed like John. After Amber’s bad breakup with Kyle, she is no longer attracted or interested in guys with blonde hair and blonde eyes, which is called the peak shift. Many of us do this subconsciously and are not even aware. This explains why so many of us go after a certain "type" after a relationship/breakup.