habituation of innate defensive behaviors is also adaptive in humans, such as habituation of a startle response to a sudden loud noise. but habituation is much more ubiquitous even in humans. an example of habituation that is an essential element of everyone's life is the changing response to food as it is repeatedly experienced during a meal. when people eat the same food during a meal, they begin to respond less to the food as they become habituated to the motivating properties of the food and decrease their consumption. eating less during a meal is usually interpreted as reaching satiety or "getting full", but experiments suggest that habituation also plays an important role. many experiments with animals and humans have shown that providing variety in a meal increases the amount that is consumed in a meal, most likely because habituation is stimulus specific and because variety may introduce dishabituation effects. food variety also slows the rate of habituation in children and may be an important contributing factor to the recent increases in obesity.