Sensitization and habituation of motivated behavior in overweight and non-overweight children

Abstract

The rate of habituation to food is inversely related to energy intake, and overweight children may habituate slower to food and consume more energy. This study compared patterns of sensitization, as defined by an initial increase in operant or motivated responding for food, and habituation, defined by gradual reduction in responding, for macaroni and cheese and pizza in overweight and nonoverweight 8−12 year-old children. Non-overweight children habituated faster to both foods than overweight children (p = 0.03). All children recovered motivated responding for a new food (chocolate). Overweight children consumed more energy than non-overweight children (p = 0.0004). Children who showed a sensitization in responding consumed more food (p = 0.001), and sensitization moderated the effect of overweight on habituation, with slower habituation for overweight children who sensitized (p < 0.0001). This study replicates previous data on overweight/ non-overweight differences in habituation of food and of energy intake, and provides new information that individual differences in sensitization and habituation of motivated responding to food cues may be associated with a sustained motivation to eat, resulting in greater energy intake. KeywordsHabituation; motivated responding; energy intake; obesity; children Habituation to food, as defined by a gradual reduction in responding to repeated presentations of a stimulus (Groves & Thompson, 1970) occurs in rodents, non-human primates and humans across a wide variety of responses. Habituation to food stimuli have been observed in rats using mouthing responses Swithers-Mulvey, Miller, & Hall, 1991;Swithers-Mulvey, Mishu, & Hall, 1992;Swithers, 1995Swithers, , 1996Swithers & Hall, 1994) and the electrophysiology of mouthing (Swithers, Westneat, & Hall, 1998), in non-human primates by habituation of single cell brain responses (Rolls, Sienkiewicz, & Yaxley, 1989;Rolls, Yaxley, & Sienkiewicz, 1990). Habituation to food has been observed in child and adult humans using salivation (Epstein, Rodefer, Wisniewski, & Caggiula, 1992;Epstein et al., 2003;, electrophysiology of mouthing in adults (Epstein & Paluch, 1997), and in motivated behavior, or operant responding to obtain food for Publisher's Disclaimer:This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. (Epstein et al., 2003;Myers Ernst & Epstein, 2002;Temple, Giacomelli, Roemmich, & Epstein, 2008;Temple et al., 2006). In each of these studies a decrement in response was observed to repeated presentations of the same food, with a recovery of responses when a new food was presented or the inhibition of habituati...

Reward activity in satiated overweight women is decreased during unbiased viewing but increased when imagining taste: an event-related fMRI study

“…Previous studies have shown that there is a slower habituation to a taste stimulus in obese participants as compared with lean ones, 54 as well as a greater effect of sensitization on responding for food in overweight versus non-overweight children. 55 Therefore, it is possible that the overweight participants were sensitized by the unbiased viewing condition and therefore showed an elevated response during taste imagination, whereas the healthy-weight were habituated after unbiased viewing and therefore showed a decreased response during Ambivalent reward activity in overweight women A Frankort et al , hunger sensations may have differed between groups during the taste imagination condition, although they were similar at the start of the scanning session. Increased hunger in the overweight group could thus have led to the elevated response during taste imagination in this group.…”

‘I just can’t help myself’: effects of food-cue exposure in overweight and lean individuals

“…Finding heightened salivary reactivity in overweight individuals is consistent with previous research demonstrating that overweight adults and children are slower to achieve salivary habituation after repeated exposure to a food cue. 20,21,25 In relation to energy intake, food-cue exposure can have two consequences; it can prime an individual to engage in eating behavior and it can increase the amount of food that is selected and subsequently consumed. 7 We found overweight/lean differences only in the former.…”

“…Also, overweight children are slower to show salivary habituation after repeated exposure to a food cue. 20,21 In adults, obese individuals salivate more in response to a food cue and are slower to develop salivary habituation. [22][23][24][25] However, these findings might otherwise be explained by differences in dietary restraint, [26][27][28][29][30] which is correlated with body mass index (BMI).…”

Long-term habituation to food in obese and nonobese women

“…The rate of habituation to food is related to food consumption, because slower rates of habituation are associated with greater energy intake (4)(5)(6). The rate of habituation within an eating session differs between obese and lean subjects, with obese subjects habituating at a slower rate than leaner subjects (5,7,8). The rate of habituation also predicts weight gain in children, because those who habituate slower show greater gains in BMI z scores than do those who habituate at a faster rate (9).…”

“…Obese adults (7,13) or overweight children (5,8) habituate at slower rates to repeated food stimuli than do leaner subjects.…”