Mapping the tip of the tongue--deprivation, sensory sensitisation, and oral haptics

We investigated the impact of food deprivation on oral and manual haptic size perception of food and non-food objects. From relevant theories (need-proportional perception, motivated perception, frustrative nonreward, perceptual defence, and sensory sensitisation) at least four completely different competing predictions can be derived. Testing these predictions, we found across four experiments that participants estimated the length of both non-food and food objects to be larger when hungry than when satiated, which was true only for oral haptic perception, while manual haptic perception was not influenced by hunger state. Subjectively reported hunger correlated positively with estimated object size in oral, but not in manual, haptic perception. The impact of food deprivation on oral perception vanished after oral stimulations even for hungry individuals. These results favour a sensory sensitisation account maintaining that hunger itself does not alter oral perception but the accompanying lack of sensory stimulation of the oral mucosa. Both oral and manual haptic perception tended to underestimate actual object size. Finally, an enhancing effect of domain-target matching was found, ie food objects were perceived larger by oral than by manual haptics, while non-food objects were perceived larger by manual than by oral haptics.     

An evaluation of emerging preference for non‐preferred foods targeted in the treatment of food selectivity

Several studies have shown that the acquisition of food consumption does not occur until after escape prevention is implemented. However, the mechanism responsible for the maintenance of food consumption may be due to participants contacting the reinforcing properties of food targeted during intervention such that the food naturally reinforces food consumption. The present study extended the literature on feeding disorders by conducting pre‐ and post‐treatment preference assessments to determine if preference for non‐preferred foods (NPFs) had developed after exposure to a treatment comparison of sequential and simultaneous food presentation; presentation methods were implemented alone and combined with escape prevention in the form of a non‐removal of the spoon (NRS) procedure. Results for three participants with food selectivity indicated that preference for NPFs developed after being exposed to those foods during either treatment sessions or generalization probes. Copyright © 2010 John Wiley & Sons, Ltd.     

Food pleasantness affects visual selective attention

Fundamental to adaptive behaviour is the ability to select environmental objects that best satisfy current needs and preferences. Here we investigated whether temporary changes in food preference influence visual selective attention. To this end, we exploited the fact that when a food is eaten to satiety its motivational value and perceived pleasantness decrease relative to other foods not eaten in the meal, an effect termed sensory-specific satiety. A total of 26 hungry participants were fed until sated with one of two palatable foods. Before and after selective satiation, participants rated the pleasantness of the two foods and then viewed the same as stimuli on a computer screen while attention was assessed by a visual probe task. Results showed that the attentional bias for the food eaten decreased markedly from pre- to postsatiety, along with the subjective pleasantness for that food. By contrast, subjective pleasantness and attentional bias for the food not eaten did not show any such decrease. These findings suggest that the allocation of visual selective attention is flexibly and rapidly adjusted to reflect temporary shift in relative preference for different foods.     

Picture recognition of food by macaques (<Emphasis Type="Italic">Macaca silenus</Emphasis>)

Pictorial representations of three-dimensional objects are often used to investigate animal cognitive abilities; however, investigators rarely evaluate whether the animals conceptualize the two-dimensional image as the object it is intended to represent. We tested for picture recognition in lion-tailed macaques by presenting five monkeys with digitized images of familiar foods on a touch screen. Monkeys viewed images of two different foods and learned that they would receive a piece of the one they touched first. After demonstrating that they would reliably select images of their preferred foods on one set of foods, animals were transferred to images of a second set of familiar foods. We assumed that if the monkeys recognized the images, they would spontaneously select images of their preferred foods on the second set of foods. Three monkeys selected images of their preferred foods significantly more often than chance on their first transfer session. In an additional test of the monkeys’ picture recognition abilities, animals were presented with pairs of food images containing a medium-preference food paired with either a high-preference food or a low-preference food. The same three monkeys selected the medium-preference foods significantly more often when they were paired with low-preference foods and significantly less often when those same foods were paired with high-preference foods. Our novel design provided convincing evidence that macaques recognized the content of two-dimensional images on a touch screen. Results also suggested that the animals understood the connection between the two-dimensional images and the three-dimensional objects they represented.     

特质自我控制对食物线索注意偏向的影响及干预：来自眼动的证据

采用眼动技术,以BMI指数处于正常范围的女性为被试,考察特质自我控制对食物线索注意偏向的影响以及注意偏向训练在改变注意偏向强度上的干预效果。结果发现,对于高热量食物线索,低特质自我控制水平女性表现出了更强的注意偏向;注意偏向训练有效降低了低特质自我控制水平女性对高热量食物线索注意偏向的强度。上述结果表明,特质自我控制影响个体对食物线索的注意偏向,注意偏向训练能有效改变个体对食物线索注意偏向的强度。     

The effects of presentation time on preference for curvature of real objects and meaningless novel patterns

Objects with curved contours are generally preferred to sharp‐angled ones. In this study, we aim to determine whether different presentation times influence this preference. We used images of real objects (experiment 1) and meaningless novel patterns (experiment 2). Participants had to select one of two images from a contour pair, curved and sharp‐angled versions of the same object/pattern. With real objects, the preference for curved versions was greatest when presented for 84 ms, and it faded when participants were given unlimited viewing time. Curved meaningless patterns were preferred when presented for 84 and 150 ms. However, in contrast to real objects, preference for meaningless patterns increased significantly in the unlimited viewing time condition. Participants discriminated poorly between the two versions (curved and sharp‐angled) of the meaningless patterns in the 84‐ and 150‐ms presentations (experiment 3). Therefore, in short times with meaningless patterns, participants selected mostly the curved version without being aware of the difference. In conclusion, presentation time, type of stimulus, and their interaction influence preference for curvature.     

在线抑制控制训练对失败的限制性饮食者不健康食物选择的改善

失败的限制性饮食者是进食障碍的高危人群,他们面对食物时的抑制控制能力通常很弱,从而更易发展为肥胖,所以改善失败的限制性饮食者对不健康食物的进食选择十分重要。本文采用在线停止信号任务,通过提高失败的限制性饮食者对不健康食物图片的抑制控制能力,从而减少他们在日常生活中对不健康食物的选择。首先对66名失败的限制性饮食者实施前测,然后随机分为对不健康食物图片进行抑制反应的干预组(n=33)和对非食物图片进行抑制反应的控制组(n=31),两组被试接受每天一次(每次10 min左右)共计7次的训练。完成训练后,所有被试均接受后测。结果发现,干预训练后,与控制组相比,干预组被试对不健康食物的选择频率以及对不健康食物自我报告的吸引力和喜爱程度均显著降低。     

Subjective Happiness and Emotional Responsiveness to Food Stimuli

Through three studies, this study aims to investigate the relationship between subjective happiness and responsiveness to eating and to foods. In Study 1, 299 Japanese undergraduates completed the Japanese subjective happiness scale and self-report questionnaires for attitudes toward eating and food. Study 1 revealed that in daily life, people with higher happiness levels show a stronger tendency to feel pleasure by eating than those with lower happiness levels. In Study 2, 26 Japanese undergraduates performed impression assessments for foods when looking at pictures of them. In Study 3, 22 Japanese undergraduates performed the same assessments when looking at real foods and eating them using a comparison with the data from pictures of non-food items as a control condition. The results of the study indicate that people with higher happiness levels show a stronger emotional response (happy and glad) to food stimuli than those with lower happiness levels. Even images of food were effective. No such group differences were observed for appetitive responses. It was also shown that emotional responses to the pictures of non-food items’ condition in the two groups did not differ. The present studies provided empirical evidence that subjective happiness has relevance to daily eating behavior and attitudes. Further studies should investigate the possibility that subjective happiness is related to a wide range of behavior and cognition in our daily life.     

Can rhesus monkeys spontaneously subtract?

Animals, including pigeons, parrots, raccoons, ferrets, rats, New and Old World monkeys, and apes are capable of numerical computations. Much of the evidence for such capacities is based on the use of techniques that require training. Recently, however, several studies conducted under both laboratory and field conditions have employed methods that tap spontaneous numerical representations in animals, including human infants. In this paper, we present the results of 11 experiments exploring the capacity of semi-free-ranging adult rhesus monkeys to spontaneously compute (i.e. single trial, no training) the outcome of subtraction events. In the basic design, we present one quantity of objects on one stage, a second quantity on a second stage, occlude both stages, and then remove one or no objects from each stage. Having watched these events, a subject is then allowed to approach one stage and eat the food objects behind the occluder. Results show that rhesus monkeys correctly compute the outcome of subtraction events involving three or less objects on each stage, even when the identity of the objects is different. Specifically, when presented with two food quantities, rhesus monkeys select the larger quantity following subtractions of one piece of food from two or three; this preference is maintained when subjects must distinguish food from non-food subtractions, and when food is subtracted from either one or both initial quantities. Furthermore, rhesus monkeys are capable of representing zero as well as equality when two identical quantities are contrasted. Results are discussed in light of recent attempts to determine how number is represented in the brains of animals lacking language.     

The Impact of Ruminative Processing on the Experience of Self-Referent Intrusive Memories in Dysphoria

The current study sought to experimentally assess the differential effects of analytical ruminative processing and distraction on the experience of self-referent naturally occurring intrusive memories in a sample of dysphoric (BDI-II ≥ 12) participants. Seventy-seven undergraduate participants completed a memory interview to elicit details about a self-referential intrusion and were randomly assigned to either an analytical rumination or distraction condition. Subsequent to the rumination induction, participants rated their intrusive memory as more negative, more distressing, and more evocative of a negative emotional response compared to participants who were allocated to the distraction induction. Inducing analytical rumination also resulted in participants reporting worse (i.e., more sad) mood relative to those in the distraction condition. The findings align with the suggestion that depressed individuals may get caught up in a ruminative cycle that, due to the documented effects of analytical self-focus, exacerbate the emotional response elicited by intrusions and perpetuate biased attentional focus on them. Directions for future investigations of the cognitive processes that are important in the maintenance of intrusions in depressive disorders are discussed.     

The effects of constant versus varied reinforcers on preference and resistance to change

Previous research has demonstrated that factors such as reinforcer frequency, amount, and delay have similar effects on resistance to change and preference. In the present study, 4 boys with autism made choices between a constant reinforcer (one that was the same food item every trial) and a varied food reinforcer (one that varied randomly between three possible food items). For all 4 boys, varied reinforcers were preferred over constant reinforcers, and they maintained higher response rates than constant reinforcers. In addition, when a distraction (a video clip) was introduced, responding maintained by varied reinforcers was more resistant to distraction than responding maintained by constant reinforcers. Thus, the present experiment extended the generality of the relation between preference and resistance to change to variation in reinforcer quality.     

Recognition and categorization of biologically significant objects by rhesus monkeys (Macaca mulatta): the domain of food.

To survive, organisms must be able to identify edible objects. However, we know relatively little about how humans and other species distinguish food items from non-food items. We tested the abilities of semi-free-ranging rhesus monkeys (Macaca mulatta) to learn rapidly that a novel object was edible, and to generalize their learning to other objects, in a spontaneous choice task. Adult monkeys watched as a human experimenter first pretended to eat one of two novel objects and then placed replicas of the objects at widely separated locations. Monkeys selectively approached the object that the experimenter had previously eaten, exhibiting a rapidly induced preference for the apparently edible object. In further experiments in which the same objects were used as tools or were manipulated at the face but not eaten, we fail to observe an approach bias, providing evidence that the monkeys' pattern of approach in the earlier experiments was specific to objects that were eaten. Subsequent experiments tested how monkeys generalized their preference for an edible object by first allowing them to watch a human experimenter eat one of two objects and then presenting them with new objects composed of the same substance but differing from the original, edible object in shape or color. Monkeys ignored changes in the shape of the object and generalized from one edible object to another on the basis of color in conjunction with other substance properties. Finally, we extended this work to infant rhesus monkeys and found that, like adults, they too used color to generalize to novel food objects. In contrast to adults, however, infants extended this pattern of generalization to objects that were acted on in other ways. These results suggest that infant monkeys form broader object categories than adults, and that food categories become sharpened as a function of maturational or experiential factors.     

Relation between food preference and food-elicited vocalizations in golden lion tamarins (Leontopithecus rosalia).

We report the results of 2 studies on food-elicited vocalizations in golden lion tamarins (Leontopithecus rosalia). First, we investigated the preferences of 10 golden lion tamarins for 6 foods. Tamarins prefer mealworms and raisins significantly more than apple, egg, carrot, or marmoset diet. Food preference rank was significantly and positively correlated with the rank of latency to choose a particular food. Second, we investigated the relation between food preference and 15 vocal parameters measured from the calls emitted by 5 tamarins to a subset of the foods. Only 1 parameter was significantly correlated with food preference across animals. Within-subjects multivariate analysis of variance showed that the vocalizations to foods are significantly different. Our results support an hypothesis that food-elicited vocalizations vary in ways that correspond to the caller's preference but not in a manner that labels food type.     

Reduce temptation or resist it? Experienced temptation mediates the relationship between implicit evaluations of unhealthy snack foods and subsequent intake

A more negative implicit evaluation of unhealthy food stimuli and a more positive implicit evaluation of a weight-management goal have been shown to predict lower consumption of unhealthy food. However, the associations between these evaluations, temptation to indulge and consumption of unhealthy food remain unclear. The current study investigated whether temptation would mediate the relationship between implicit food and goal evaluations and consumption (resembling an antecedent-focused route to self-control of eating), or whether those evaluations would moderate the relationship between temptation and consumption (resembling a response-focused route). A sample of 156 women (17–25 years), who tried to manage their weight through healthy eating, completed two implicit association tasks assessing implicit food and goal evaluations, respectively. Intake of four energy-dense snack foods was measured in a task disguised as a taste test, and participants reported the strength of experienced temptation to indulge in the snacks offered. Negative implicit food evaluation was associated with lower snack intake, and temptation mediated this relationship. Implicit goal evaluation was unrelated to both temptation strength and snack consumption. The findings contribute to an understanding of how negative implicit unhealthy food evaluation relates to lower consumption, namely through the mediation of temptation to indulge in those foods.     

Incremental theories of weight and healthy eating behavior

We examined whether a belief in weight as malleable (an incremental theory) leads to healthier eating than a belief that weight is fixed (an entity theory). Participants with incremental theories of weight consumed fewer calories from high‐calorie foods in a lab‐based taste‐test than did those with more entity theories of weight. This pattern held correlationally, with naturally occurring theories of weight (Study 1), and when we experimentally manipulated participants’ theories of weight (Study 2). A third study provided evidence that differences in self‐efficacy regarding food mediate the relationship between theories of weight and eating behavior (Study 3). One way to encourage healthy eating might be to develop interventions that encourage more incremental views of weight.     

Sensation seeking and food preferences

The relationships between sensation seeking and preferences for various foods were studied. A Japanese version of the Sensation Seeking Scale (SSS) and food preference questionnaire were administered to a total of 105 students (66 males and 39 females). Preference ratings of 70 foods were factor analyzed and 7 factors concerning food preference patterns were extracted. Preference ratings for food items with high loadings on these 7 factors were correlated with subjects' scores on SSS. Significant and positive correlations were found between total scores of SSS and the preference ratings for spicy foods (loading on factor 1), meats (loading on factor 4), and alcoholic beverages (loading on factor 6). Among subscales of SSS, following subscores correlated significantly and positively with preference for several food groups: (1) ES, TAS and spicy foods. (2) TAS and meats, ES and a few items of meats. (3) TAS, BS and alcoholic beverages. But, Dis scale did not correlate with any food groups. Common features and differences between the results of present research and previous ones connected in the U.S.A. were discussed.     

Limits to preference and the sensitivity of choice to rate and amount of food

Studies of choice holding food‐amount ratio constant while varying food‐rate ratio within sessions showed that local changes in preference depend on relative amount of food. The present study investigated whether sensitivity of choice to food‐rate ratio and sensitivity to food‐amount ratio are independent of one another when food‐rate ratios are varied across sessions and food‐amount ratios are varied within sessions. Food deliveries for rats’ presses on the left and right levers were scheduled according to three different food‐rate ratios of 1:1, 9:1, and 1:9; each food‐rate ratio lasted for 106 sessions and was arranged independently of seven food‐amount ratios (7:1, 6:2, 5:3, 4:4, 3:5, 2:6, and 1:7 food pellets) occurring within sessions in random sequence. Each amount ratio lasted for 10 food deliveries and was separated from another by a 60‐s blackout. Sensitivity to rate ratio was high (1.0) across food deliveries. Sensitivity to amount ratio was low when food rates were equal across alternatives, but was high when rate ratio and amount ratio opposed one another. When rate ratio and amount ratio went in the same direction, choice ratio reached an elevenfold limit which reduced sensitivity to approximately zero. We conclude that three factors affect sensitivity to amount: (1) the limit to preference, (2) the equal effect on preference of amounts greater than four pellets, and (3) the absence of differential effects of switches in amount in the equal‐rates (1:1) condition. Taken together, these findings indicate that rate and amount only sometimes combine independently as additive variables to determine preference when amount ratios vary frequently within sessions.     

A systematic evaluation of food textures to decrease packing and increase oral intake in children with pediatric feeding disorders

This study examined packing (pocketing or holding accepted food in the mouth) in 3 children who were failing to thrive or had inadequate weight gain due to insufficient caloric intake. The results of an analysis of texture indicated that total grams consumed were higher when lower textured foods were presented than when higher textured foods were presented. The gram intake was related directly to levels of packing. That is, high levels of packing were associated with higher textured foods and low gram intake, and low levels of packing were associated with lower textured foods and high gram intake. All participants gained weight when texture of foods was decreased. Packing remained low during follow-up for 2 participants even when the texture of food was increased gradually over time. These data are discussed in relation to avoidance, response effort, and skill deficit.     

Some determinants of changes in preference over time

Results of longitudinal studies suggest that the stability of preferences varies across individuals, although it is unclear what variables account for these differences. We extended this work by conducting periodic assessments of preference for leisure activities over 3 to 6 months with 10 adults with developmental disabilities. Although previous research has collectively shown that preferences identified via repeated assessment are highly variable, our results showed that preferences were relatively stable for the majority (80%) of participants. In an attempt to identify some environmental determinants of shifts in preference, we provided extended daily access to high-preference items (preference-weakening manipulation) and paired access to low-preference items with social and edible putative reinforcers during brief sessions (preference-strengthening manipulation). Preference assessments continued over the course of these manipulations with 2 participants. Results showed that changes in preference across time could be produced systematically and suggest that naturally occurring changes in establishing operations or conditioning histories contribute to temporal shifts in preference. Implications for preference assessments, reinforcer usage, and planned attempts to change preferences are discussed.     

Increasing variety of foods consumed by blending nonpreferred foods into preferred foods

A treatment with differential or noncontingent reinforcement and nonremoval of the spoon increased the acceptance of one or two of 16 foods for 2 participants with severe food refusal. These differential levels of acceptance were demonstrated empirically in an ABAB design in which A was the presentation of the accepted (preferred) foods and B was the presentation of foods the participants refused (nonpreferred foods). Subsequently, we implemented a blending treatment that consisted of mixing (blending) nonpreferred foods into preferred foods in various ratios (e.g., 10% nonpreferred/90% preferred, 20% nonpreferred/80% preferred). We then presented nonpreferred foods that had been exposed to blending to determine if consumption of nonpreferred foods would increase following the blending treatment. We also conducted periodic reversals in which we presented nonpreferred foods that had not been exposed to the blending treatment. Following initial implementation of the blending treatment, consumption was high for nonpreferred foods that had been blended and low for nonpreferred foods that had not been blended. Consumption increased for all foods (i.e., foods that had been exposed to blending and foods that had not been exposed to blending) after seven or eight foods had been exposed to the blending treatment. Thus, the variety of foods consumed by the participants increased from one or two to 16. These results are discussed in terms of stimulus fading, conditioned food preferences, and escape extinction. DESCRIPTORS: conditioned food preferences, food refusal, negative reinforcement, stimulus fading