Peak-Shift Effect

Peak-Shift Effect Definition: The Peak-Shift Effect occurs when a person or animal, after learning to discriminate between different stimuli, may show a stronger response to a stimulus that is 'more extreme' than the original target stimulus. Example: If you train someone to distinguish between a 'large circle' and a 'small circle,' and reward them for choosing the large circle, they might actually prefer an 'extra-large circle' when presented with one. Why it Happens: The brain doesn't just remember 'which stimulus gets a reward.' It may also learn the relative differences between stimuli, pushing the response in a more extreme direction. Applied Concepts: Animal behavior research Perceptual and discrimination learning Psychological experiments Studies on certain preference and categorization behaviors Key Point: It's not simply 'the more, the better,' but rather that after learning to discriminate between two stimuli, the response may surpass the originally rewarded stimulus. Memory: 'Once a preference for a certain direction is learned, even more extreme versions might become preferred.'