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Effects of nicotinic receptor agonists on locomotor activity and the appetitive and consummatory components of feeding
ARTICLE IN PRESS 264
Abstracts / Appetite 47 (2006) 257–279
Learned influences on human food choice and intake: A review.
E.L. GIBSON. School of Human and Life Sciences, Roehampton University, Whitelands College, Holybourne Avenue, London SW15 4JD, UK Learning underlies the development and regulation of habitual eating, including our likes and dislikes, choosing foods appropriate to our current state, and control of meal size. In young children, mere exposure to the flavour of a food increases acceptance of that food. Children’s food preferences are strongly correlated with the energy density of foods, probably due to the reinforcing effects of energy eaten when hungry, i.e. flavour–consequence learning. Carbohydrate, fat and protein have all proved effective in reinforcing flavour preferences. Flavours associated with higher energy consumption are preferred when hungry, but conversely less liked when full than lower energy-paired flavours, and they suppress subsequent intake. Sensitivity to postingestive energy differences may weaken with age and externalisation of eating. Frequent eating of high-fat foods may impair neural inhibition of learned appetite, leading to overeating and obesity. Flavour–flavour learning occurs when a neutral flavour is eaten together with a flavour that already has positive or, more robustly, aversive properties. An important question is whether explicit awareness of flavour–consequence or flavour–flavour associations is needed for learned control of eating, because of implications for who should be held accountable for unhealthy eating behaviour. doi:10.1016/j.appet.2006.07.024
Effects of nicotinic receptor agonists on locomotor activity and the appetitive and consummatory components of feeding.
CLARE E. GREENHALGH, PETER G. CLIFTON. Department of Psychology, School of Life Sciences, University of Sussex, Brighton, BN1 9QG, UK Nicotinic acetylcholine receptors are expressed throughout the nervous system including areas relevant to ingestive behaviour. In rodents and humans, stimulation of nicotinic receptors and withdrawal from chronic nicotine treatment are associated, respectively, with reductions and increases in feeding behaviour. We examined effects of administering either nicotine (0.3 mg/kg sc) or cytisine (2.5 mg/kg sc) on microstructure of Intralipid intake, and on instrumental responding under a FI5:FR5(5:S) second-order operant schedule. Variations of this schedule were used to examine nicotine’s effects on responding behaviour. The sessions were video recorded. Nicotine and cytisine suppressed
Intralipid intake during the final 20 min of the 30-min session. In contrast, both drugs decreased instrumental responding in the second-order schedule during the initial 20 min of the session. Tolerance developed to the suppressive effects of nicotine in both paradigms, whereas tolerance to cytisine developed in only the instrumental paradigm. Lever pressing alternated with stereotyped patterns of behaviour whereas Intralipid drinking was relatively continuous, indicating that the differing results might relate to a reduction of locomotor activity induced by nicotine and cytisine. These data demonstrate that nicotine and cytisine have effects on patterns of activity and underlying motivational processes. The contrasting outcomes from the two paradigms may partly result from drug-related changes in behavioural patterning but are also consistent with reductions in appetitive responding supported by conditioned stimuli. doi:10.1016/j.appet.2006.07.025
Do impulse control problems cause obesity? RAMONA GUERRIERI, CHANTAL NEDERKOORN, ANITA JANSEN. Department of Experimental Psychology,
University of Maastricht, P.O. Box 616, 6200 MD Maastricht, The Netherlands
Why do obese people find it difficult to resist tasty food? Previous research has shown that obese participants are more impulsive than normal-weight controls. In the current study we investigated further whether impulsivity indeed causes overeating. We hypothesized that trait impulsivity would predict food intake in normal-weight women. Moreover, we expected that priming the concept impulsivity would lead to increased food intake. Normal-weight women participated in two bogus taste tests. Before each taste test they were primed with either the impulsivity concept (no reference to food was made) or neutral concepts, in balanced order. Trait impulsivity was also measured. Analyses show that trait impulsivity significantly predicts total food intake. In addition, the priming task had a significant effect on how much participants wanted to eat the food when exposed to it. More precisely, participants wanted to eat more after the priming of impulsivity compared to neutral priming. However, this effect did not extend to food intake. This study links impulsiveness to food intake in healthy women. This lends more credibility to the possibility that impulsiveness is one of the factors that play a causal role in obesity. doi:10.1016/j.appet.2006.07.026
Abstracts / Appetite 47 (2006) 257–279
Learned influences on human food choice and intake: A review.
E.L. GIBSON. School of Human and Life Sciences, Roehampton University, Whitelands College, Holybourne Avenue, London SW15 4JD, UK Learning underlies the development and regulation of habitual eating, including our likes and dislikes, choosing foods appropriate to our current state, and control of meal size. In young children, mere exposure to the flavour of a food increases acceptance of that food. Children’s food preferences are strongly correlated with the energy density of foods, probably due to the reinforcing effects of energy eaten when hungry, i.e. flavour–consequence learning. Carbohydrate, fat and protein have all proved effective in reinforcing flavour preferences. Flavours associated with higher energy consumption are preferred when hungry, but conversely less liked when full than lower energy-paired flavours, and they suppress subsequent intake. Sensitivity to postingestive energy differences may weaken with age and externalisation of eating. Frequent eating of high-fat foods may impair neural inhibition of learned appetite, leading to overeating and obesity. Flavour–flavour learning occurs when a neutral flavour is eaten together with a flavour that already has positive or, more robustly, aversive properties. An important question is whether explicit awareness of flavour–consequence or flavour–flavour associations is needed for learned control of eating, because of implications for who should be held accountable for unhealthy eating behaviour. doi:10.1016/j.appet.2006.07.024
Effects of nicotinic receptor agonists on locomotor activity and the appetitive and consummatory components of feeding.
CLARE E. GREENHALGH, PETER G. CLIFTON. Department of Psychology, School of Life Sciences, University of Sussex, Brighton, BN1 9QG, UK Nicotinic acetylcholine receptors are expressed throughout the nervous system including areas relevant to ingestive behaviour. In rodents and humans, stimulation of nicotinic receptors and withdrawal from chronic nicotine treatment are associated, respectively, with reductions and increases in feeding behaviour. We examined effects of administering either nicotine (0.3 mg/kg sc) or cytisine (2.5 mg/kg sc) on microstructure of Intralipid intake, and on instrumental responding under a FI5:FR5(5:S) second-order operant schedule. Variations of this schedule were used to examine nicotine’s effects on responding behaviour. The sessions were video recorded. Nicotine and cytisine suppressed
Intralipid intake during the final 20 min of the 30-min session. In contrast, both drugs decreased instrumental responding in the second-order schedule during the initial 20 min of the session. Tolerance developed to the suppressive effects of nicotine in both paradigms, whereas tolerance to cytisine developed in only the instrumental paradigm. Lever pressing alternated with stereotyped patterns of behaviour whereas Intralipid drinking was relatively continuous, indicating that the differing results might relate to a reduction of locomotor activity induced by nicotine and cytisine. These data demonstrate that nicotine and cytisine have effects on patterns of activity and underlying motivational processes. The contrasting outcomes from the two paradigms may partly result from drug-related changes in behavioural patterning but are also consistent with reductions in appetitive responding supported by conditioned stimuli. doi:10.1016/j.appet.2006.07.025
Do impulse control problems cause obesity? RAMONA GUERRIERI, CHANTAL NEDERKOORN, ANITA JANSEN. Department of Experimental Psychology,
University of Maastricht, P.O. Box 616, 6200 MD Maastricht, The Netherlands
Why do obese people find it difficult to resist tasty food? Previous research has shown that obese participants are more impulsive than normal-weight controls. In the current study we investigated further whether impulsivity indeed causes overeating. We hypothesized that trait impulsivity would predict food intake in normal-weight women. Moreover, we expected that priming the concept impulsivity would lead to increased food intake. Normal-weight women participated in two bogus taste tests. Before each taste test they were primed with either the impulsivity concept (no reference to food was made) or neutral concepts, in balanced order. Trait impulsivity was also measured. Analyses show that trait impulsivity significantly predicts total food intake. In addition, the priming task had a significant effect on how much participants wanted to eat the food when exposed to it. More precisely, participants wanted to eat more after the priming of impulsivity compared to neutral priming. However, this effect did not extend to food intake. This study links impulsiveness to food intake in healthy women. This lends more credibility to the possibility that impulsiveness is one of the factors that play a causal role in obesity. doi:10.1016/j.appet.2006.07.026