response in adult caretaking. The study also noted that perceived cuteness was also dependent on other physical and behavioural characteristics of the child, including age. In a study by McCabe (1984) of children whose ages ranged from toddlers to teenagers, the children with more "adult-like" facial proportions were more likely to have experienced physical abuse than children of the same age who had less "adult-like" facial proportions. A study by Karraker (1990) suggested that "an adult's beliefs about the personality and expected behavior of an infant can influence the adult's interaction with the infant", and gave evidence that in this way "basic cuteness effects may occasionally be obscured in particular infants". Koyama (2006) said that an adult caregiver's perception of an infant's cuteness can motivate the amount of care and protection the caregiver provides, and the admiration demonstrated toward the infant, and concluded that "the adults' protective feeling for children appeared to be a more important criterion for the judgment of a boy's cuteness." Melanie Glocker (2009) provided experimental evidence that infants' cuteness motivates caretaking in adults, even if they are not related to the infant. Glocker asked individuals to rate the level of cuteness of pictured infants and noted the motivation that these participants had to care for the infants. The research suggested that individuals' rating of the perceived cuteness of an infant corresponded to the level of motivation an individual had to care for this infant. Glocker and colleagues then used functional magnetic resonance imaging (fMRI), to demonstrate that baby faces with higher content of baby schema features, generated more activation in the nucleus accumbens, a small brain area central to motivation and reward. This work elucidated the neural mechanism through which baby schema (Kindchenschema) may motivate ("release") caretaking behavior. Furthermore, cute infants were more likely to be adopted and rated as more "likeable, friendly, healthy and competent" than infants who were less cute. There is an implication that baby schema response is crucial to human development because it lays the foundation for caregiving and the relationship between child and caretaker. Sherman, Haidt, & Coan (2009), in two experiments, found that exposure to high cuteness stimuli increased performance when playing the Operation game, a task that requires extreme carefulness. The study said that the shift in behavior toward greater carefulness is consistent with the viewpoint that cuteness is something that releases the human caregiving system. The study said