Melanie presents infants with the same red light repeatedly until the infants quit looking at it. she then presents a new, slightly different colored light and records whether the infants resume responding. this is an example of:

habituationHabituation is a mental learning process in infants wherein repeated exposure to a stimulus results in a decreased response to it. In this example, after Melanie presented the infants with the same red light repeatedly, they became "habituated" or familiar with it, after which they lost interest in observing it. Melanie then proceeds to investigate if the infants instead turn their attention to a different colored light (a new stimulus).