Stock optimizing in choice when a token deposit is the operant.

Each of 2 monkeys typically earned their daily food ration by depositing tokens in one of two slots. Tokens deposited in one slot dropped into a bin where they were kept (token kept). Deposits to a second slot dropped into a bin where they could be obtained again (token returned). In Experiment 1, a fixed-ratio (FR) 5 schedule that provided two food pellets was associated with each slot. Both monkeys preferred the token-returned slot. In Experiment 2, both subjects chose between unequal FR schedules with the token-returned slot always associated with the leaner schedule. When the FRs were 2 versus 3 and 2 versus 6, preferences were maintained for the token-returned slot; however, when the ratios were 2 versus 12, preference shifted to the token-kept slot. In Experiment 3, both monkeys chose between equal-valued concurrent variable-interval variable-interval schedules. Both monkeys preferred the slot that returned tokens. In Experiment 4, both monkeys chose between FRs that typically differed in size by a factor of 10. Both monkeys preferred the FR schedule that provided more food per trial. These data show that monkeys will choose so as to increase the number of reinforcers earned (stock optimizing) even when this preference reduces the rate of reinforcement (all reinforcers divided by session time).     

USING A FADING PROCEDURE TO INCREASE FLUID CONSUMPTION IN A CHILD WITH FEEDING PROBLEMS

Stimulus fading was combined with differential reinforcement and extinction to increase intake of a calorie‐dense fluid by a 6‐year‐old child with feeding problems. The fading procedure consisted of adding Carnation Instant Breakfast? Final acceptance and then milk to water (a fluid the child would drink).     

The influence of caloric information on cafeteria food choices

We evaluated the effect of posting caloric information on food purchases at a cafeteria. Purchases of more than 14,300 entrees, vegetables, and salads by 6,970 customers were unobtrusively monitored via the cash register inventory control system during 15 evening observations. A quasi-multiple-baseline design across food groups was used to test the additive effect of labeling the three lowest caloric choices for vegetables, salads, and entrees. A linear logit analysis confirmed that labeling increased the probability of low calorie selections for vegetables and salads, but not for entrees. Observations of meals purchased by a subsample of 413 customers indicated labeling did not change the total caloric content of meals. The number of customers and total sales per evening were unaffected by the labeling intervention. The results suggest that manipulating environmental cues may be an effective method for changing food purchases in a cafeteria, but labeling individual items may not be the best way to decrease total calories purchased.     

Positive behavioral contrast when pigeons press treadles during multiple schedules

Pigeons were placed on multiple variable-interval 15-second variable-interval 15-second and on multiple variable-interval 15-second extinction schedules in which treadle presses produced food reinforcers. Positive behavioral contrast occurred. That is, rates of responding were higher during the variable-interval 15-second component when the other component was extinction than when it was another variable-interval 15-second schedule. These results contradict the findings of other studies, which failed to find positive contrast when pigeons pressed treadles for food reinforcers. They may also question the additive theories of behavioral contrast that predict that contrast should not occur in this situation.     

Lean and mean rats: Some effects of acute changes in the food supply upon territorial aggression

In experiment 1, individually housed rats subjected to short-term food restriction displayed more territorial aggression toward conspecific intruders than controls maintained on a free-feeding diet. In experiment 2, small groups of three adult male rats had access to either a standard laboratory diet or the standard diet plus sucrose. Groups with the sucrose supplement were significantly less aggressive toward intruders than controls. Sucrose availability did not produce appreciable gains in body weight but it did reliably decrease within-colony weight variation. The results suggest the existence of an effective dietary mechanism that enables a social species such as Rattus norvegicus to tolerate each other in dense feeding aggregations when food is abundant. Conversely, when food is limited, social intolerance increases and serves to limit the development of large feeding groups.     

Teaching behavior analysts in an early intensive behavioral intervention setting to conduct a structured mealtime protocol

Children with autism spectrum disorder often display feeding problems, such as consumption of a limited variety of foods. It is also common for these children to be enrolled in early intensive behavioral intervention (EIBI) services for comprehensive treatment. Combined, these factors make it possible that behavior analysts will have a role in a child's clinical care related to feeding. However, given that the etiology of pediatric feeding disorders is complex and multifactorial, clinicians should ensure they have sufficient training and a setting that is appropriate for assessment and treatment. Therefore, we evaluated the effects of behavioral skills training in an EIBI setting to conduct a structured mealtime protocol. Training resulted in increases in procedural integrity, and we replicated these effects for all participants.     

Food rejection and the development of food category-based induction in 2–6 years old children

We studied children’s inductive inferences within the domain of food categories. There has so far been little research on inductive reasoning about food among children, despite the theoretical and practical importance of knowing what knowledge children bring to the table and how they use it. We tested the hypotheses that children’s food category-based induction performances and their food rejection are negatively correlated, and that these performances are influenced by the colour typicality of the food items. We recruited 126 children aged 2–6 years, and administered a category-based induction task. Participants were successively shown 8 sets of three pictures containing one target picture (a vegetable) and two test pictures (a vegetable dissimilar in colour to the target picture and a fruit similar in colour to the target picture). For each set, participants were told a novel property about the target picture and asked to generalise this property to one of the two test pictures. Additionally, the parents of each child filled out a questionnaire about his or her food rejection tendencies. Results on accuracy (i.e. if participants generalised the properties according to category membership, not perceptual similarity) provided the first empirical evidence in favour of a negative relationship between children’s food rejection and food category-based induction.     

纳络酮、地卓西平(MK-801)对大鼠食物渴求的影响

实验以条件性位置偏爱（CPP）的表达为渴求模型观察纳络酮及MK-801对大鼠食物CPP表达,探讨摄食行为调控的心理机制。48只SD大鼠分成食物组（24）与对照组（24）,3轮食物匹配训练后,在CPP表达前分别注射生理盐水、纳络酮（1.0 mg˙kg -1）及MK-801(0.1 mg˙kg -1),观察各组动物在食物匹配训练侧停留时间的变化。结果发现,MK-801促进食物CPP的表达,但纳络酮对食物CPP的表达没有显著影响。以上结果表明MK-801（0.1mg˙kg -1）增强动物的食物渴求至少是其增加摄食量的原因之一,而1.0 mg˙kg -1的纳络酮降低动物的摄食量并不是由于食物渴求的下降导致的。MK-801与纳络酮调节动物摄食行为的心理机制可能不一致。     

礼与食孰重:儒墨之辩新论

孔墨“俱道尧舜”但政治理想却截然不同,其主要原因在于两方面,首先是他们有着各不相同的历史传统和政治理想,其次是他们对于中国轴心时代的社会现实有着完全不同的认识和评价。两家显学的根本分歧在于“礼与食孰重”,儒家认为生活资料的匮乏是由于人的动物性欲望未能得到有效的遏制,因而特别强调了一整套礼仪制度对于文明的重要性。墨家则认为正是由于礼仪制度本身的维系严重消耗了社会的物质基础,才使得人们为了满足饥饿的食本能而不得不弱肉强食。这个思想史的问题至今仍未结束。