“We will work for you” – Social influence may suppress individual food preferences in a communicative situation in dogs

The level of motivation (i.e. incentive power) is thought to be one of the most important factors affecting performance and learning in various tasks. We investigated whether reward quality has an effect on the performance of family dogs in a two-way object choice test in which they can find the hidden food by relying on distal momentary human pointing cues. In three experiments we varied (1) the type of food reward according to the subjects’ own preference; (2) the quality of the reward offered at the same time in the indicated and not-indicated locations; and (3) the order of the high or low quality rewards in consecutive sessions. In Experiment 1, we first tested whether dogs prefer one kind of reward over another. Then one group was tested with the ‘preferred’ food as reward in the indicated bowl, while dogs in the other group received the ‘non-preferred’ food as reward. We did not find any difference between the performance and choice latencies of the two groups. In Experiment 2 for the first group, the indicated bowl contained a piece of carrot and the not-indicated bowl was empty. In the second group the indicated bowl contained carrot, but the not-indicated bowl contained sausage. According to a preliminary preference test, most dogs prefer sausage over carrot invariably. After 20 trials, the two groups performed surprisingly similarly. There was no difference found between groups in the number of correct choices, incorrect choices and non-choices. However, the comparison between the first and last five trials revealed that subjects who found sausage when they chose the not-indicated bowl (did not follow the pointing) chose the non-indicated bowl significantly more often toward the end of their test session. In Experiment 3, each dog received two sessions with 12 pointing trials in each. For the first session, one group was rewarded with sausage and the other with carrot upon choosing the indicated bowl. In the second session, the indicated bowl contained dry dog food for both groups. We found that correct choices and response latencies did not change over two sessions in the ‘sausage’ group. In the ‘carrot’ group, the dogs chose faster in the second session, but their performance did not improve; in fact, they chose the not-indicated bowl more often than the indicated bowl. As a conclusion, we can say that reward quality had some effect on dogs’ choice behavior in these experiments. The drop in their performance was not drastic, taking into account the general refusal to eat one of the ‘rewards’ (carrot) during the preference tests and also during the test trials. It seems that incentive contrast may play a relatively minor role in dog-human social interactions. Appropriate reward quality can be very important in asocial problem solving tasks, but, when interacting with humans, following human signals may override the effect of changed incentive power.     

Capuchin monkeys, inequity aversion, and the frustration effect

Each of 4 female capuchin monkeys ("model") was paired with another female capuchin ("witness") in an adjacent cage. In Phases 1 and 3, a model could remove a grape from the experimenter's hand while the witness watched. The witness was then offered a slice of cucumber, a less preferred food. Trials alternated between subjects 50 times, defining a session. In Phases 2 and 4, both were offered cucumber. Witness rejections of cucumber were infrequent and were not dependent on whether models received grape or cucumber. When models were offered cucumber, they rejected it at higher rates than did witnesses. These results fail to support findings of Brosnan and de Waal. An account based on the frustration effect accommodates these results and those of Brosnan and de Waal.     

Gender bias on the Thematic Apperception Test

Thirty male and 30 female college students generated stories to a set of nine Thematic Apperception Test (TAT) cards with either male or female stimulus characters. The Fine scoring system was factor analyzed to produce seven factor clusters plus three outcome variables. Multiple analysis of variance (MANOVA) revealed a main effect for type of card. The female TAT cards elicited significantly more responses on the General Concerns scale than did the male TAT cards. A main effect for subject gender showed the females gave more responses than males on the Interpersonal Relations scale. No differences were found on the outcome variables.     

Gender Bias on the Thematic Apperception Test

Thirty male and 30 female college students generated stories to a set of nine Thematic Apperception Test (TAT) cards with either male or female stimulus characters. The Fine scoring system was factor analyzed to produce seven factor clusters plus three outcome variables. Multiple analysis of variance (MANOVA) revealed a main effect for type of card. The female TAT cards elicited significantly more responses on the General Concerns scale than did the male TAT cards. A main effect for subject gender showed the females gave more responses than males on the Interpersonal Relations scale. No differences were found on the outcome variables.     

A prework assessment of task preferences among adults with autism beginning a supported job

A prework paired-task assessment was evaluated for identifying work preferences among 3 adults with autism beginning a supported job. When the workers began the job, choices were provided between more and less preferred tasks (determined by previous assessment). Results supported the assessment for identifying single task preferences, but did not reveal preferences of 2 workers for alternate tasks. Results are discussed in terms of evaluating other prework assessments that may reveal task-alternation preferences.     

Do orangutans (<Emphasis Type="Italic">Pongo pygmaeus</Emphasis>) know when they do not remember?

Metacognition refers to the ability to monitor and control one’s own cognitive activities such as memory. Although recent studies have raised an interesting possibility that some species of nonhuman animals might possess such skills, subjects often required a numerous number of training trials to acquire the effective use of metacognitive responses. Here, five orangutans (Pongo pygmaeus) were tested whether they were able to escape spatial memory tests when they did not remember the location of preferred reward in a relatively small number of trials. The apes were presented with two identical cups, under one of which the experimenter hid a preferred reward (e.g., two grapes). The subjects were then presented with a third container, “escape response”, with which they could receive a less preferred but secure reward (e.g., one grape). The orangutans as a group significantly more likely selected the escape response when the baiting of the preferred reward was invisible (as compared to when it was visible) and when the hiding locations of the preferred reward were switched (as compared to when they remained unchanged). Even when the escape response was presented before the final presentation of the memory test, one orangutan successfully avoided the test in which she would likely err. These findings indicate that some orangutans appear to tell when they do not remember correct answers in memory tests.     

Transitive responding in hooded crows requires linearly ordered stimuli

Eight crows were taught to discriminate overlapping pairs of visual stimuli (A+ B-, B+ C-, C+ D-, and D+ E-). For 4 birds, the stimuli were colored cards with a circle of the same color on the reverse side whose diameter decreased from A to E (ordered feedback group). These circles were made available for comparison to potentially help the crows order the stimuli along a physical dimension. For the other 4 birds, the circles corresponding to the colored cards had the same diameter (constant feedback group). In later testing, a novel choice pair (BD) was presented. Reinforcement history involving stimuli B and D was controlled so that the reinforcement/nonreinforcement ratios for the latter would be greater than for the former. If, during the BD test, the crows chose between stimuli according to these reinforcement/nonreinforcement ratios, then they should prefer D; if they chose according to the diameter of the feedback stimuli, then they should prefer B. In the ordered feedback group, the crows strongly preferred B over D; in the constant feedback group, the crows' choice did not differ significantly from chance. These results, plus simulations using associative models, suggest that the orderability of the postchoice feedback stimuli is important for crows' transitive responding.     

Are monkeys aesthetists? Rensch (1957) revisited

Three experiments assessed whether capuchin monkeys (Cebus apella) and squirrel monkeys (Saimiri sciureus) prefer regular and symmetrical visual patterns. Pictorial representations of faces were included in 1 stimulus set. When the monkeys could pick up and manipulate small cards bearing the stimuli, all preferences expressed by capuchins and most of those expressed by squirrel monkeys were for regular stimuli. Symmetry of the patterns was influential but not essential. Some preferences were also found for faces. When images of the patterns were presented on a touch screen, capuchins continued to express preferences especially for regular and symmetrical stimuli, but they showed some avoidance of faces. Squirrel monkeys responded less discriminatingly to the touch screen stimuli. The findings provide support for B. Rensch's (1957) claim that monkeys prefer visual stimuli that humans find aesthetically pleasing.     

Preference for novel flavors in adult golden hamsters (Mesocricetus auratus)

Although animals generally prefer to eat foods with familiar rather than unfamiliar flavors, adult golden hamsters (Mesocricetus auratus) were found to do the opposite. After having prolonged exposure to a food with a particular flavor, hamsters were allowed to select between the food with the familiar flavor and the same food with a novel flavor. Hamsters consistently ate more of the food with the novel flavor, and this preference was long-lasting and resistant to extinction. Furthermore, the novelty effect was robust, being manifested in both sexes and under a variety of experimental circumstances. In contrast, rats tested under identical conditions consistently preferred the food with the familiar flavor. The origins of the novelty effect in hamsters remain to be determined.     

The effect of attractiveness on food sharing preferences in human mating markets

The current study explored how physical attractiveness affects food sharing by studying payment preferences for hypothetical romantic dinner dates (a hypothetical mating market). We analyzed payment preferences, self-rated attractiveness, and rated attractiveness for hypothetical dates in 416 participants. We hypothesized that (1) men would be more likely to prefer to pay than would women, (2) attractive individuals of both sexes would be less willing to pay, and (3) preferences to enter an exchange would be influenced by the attractiveness of prospective partners such that (3a) men would prefer to pay for attractive women, and (3b) women would prefer to be paid for by attractive men. All hypotheses were supported by our results. Individuals with higher self-rated attractiveness were more likely to prefer that their date would pay for the meal, and we found clear sex differences in how the attractiveness of potential dates affected payment preferences. Male participants preferred to pay for dates that had higher facial attractiveness, while female participants preferred that attractive men would pay. Individuals show condition dependent financial preferences consistent with the provisioning hypothesis in this mating market that are adaptive to evaluations of their own quality and that of prospective partners.     

Natural choice in chimpanzees (Pan troglodytes): Perceptual and temporal effects on selective value

In three experiments, four chimpanzees made choices between two visible food options to assess the validity of the selective value effect (the assignment of value to only the most preferred type of food presented in a comparison). In Experiment 1, we established that all chimpanzees preferred single banana pieces to single apple pieces before presenting the critical test. In this test two chimpanzees preferred a mix of one banana piece and one apple piece to a single banana piece when both banana pieces were approximately the same size, but two chimpanzees were indifferent between the two options, exhibiting the selective value effect. In Experiment 2, when the banana pieces in both options were more closely equated in size, the chimpanzees were biased to choose the single banana piece over the mixed array even though this was the smaller total amount of food. However, in Experiment 3, when we introduced longer intervals between each trial, the chimpanzees preferred the mixed set and thus the larger total amount of food. The results demonstrate that only some chimpanzees exhibit the choice pattern indicative of the selective value effect, and they do so only when item size is not carefully controlled and trials are presented quickly in succession. Thus, the behavior pattern originally labeled the selective value effect may actually be explained by a combination of chimpanzees’ sensitivity to small differences in preferred food amount and chimpanzees tendency to avoid less preferred foods that would delay the acquisition of further preferred food items.     

Young Children Have Difficulty Predicting Future Preferences in the Presence of a Conflicting Physiological State

This study examined children's predictions about their future preferences when they were in two different physiological states (thirsty and not thirsty). Ninety 3‐ to 7‐year‐olds were asked to predict what they would prefer tomorrow: pretzels to eat or water to drink after having consumed pretzels, and again after having had the opportunity to quench their thirst with water. Results showed that although children initially preferred pretzels to water at baseline, they more often indicated that they would prefer water the next day after they had consumed pretzels. After consuming water, however, the same children indicated they would prefer pretzels the next day. Children's verbal justifications for their choices rarely made reference to their current or future states, but rather justifications were more likely to make reference to their general preferences when they were no longer thirsty compared to when they were thirsty. Results suggest that current physiological states have a powerful influence on future preferences. The findings are discussed in the context of the development of episodic foresight, the Bischof‐Kohler hypothesis, and the important and often overlooked role that children's current states play in future decision making. Copyright © 2015 John Wiley & Sons, Ltd.     

The stress-eating paradox: Multiple daily measurements in adult males and females

Abstract

The stress-eating relationship was examined in a prospective study of 158 subjects who completed daily records of stress and eating for 84 days, yielding 16.188 person days of observation. Using both within-subjects and between-subjects analyses, individuals were much more likely to eat less than usual than to eat more than usual in response to stressful daily problems. The likelihood of eating more did not change as severity of stress increased, but the likelihood of eating less increased substantially. There were also clear gender differences. Males had a slight tendency to eat less than to eat more across all levels of stress, except at the highest level, where eating less occurred much more frequently. In females, the tendency to eat less as opposed to eating more emerged at middle levels of stress; at the highest level of stress, females were more than three times more likely to eat less than to eat more. Individual subjects were highly consistent over levels of stress in the direction of eating; 82% of the subjects were consistent in eating more or less over the majority of their stressful periods. These results show a clear effect of stress on eating, with eating less being the predominant response.     

Incidental memory in dogs (Canis familiaris): adaptive behavioral solution at an unexpected memory test

Memory processing in nonhuman animals has been typically tested in situations where the animals are repeatedly trained to retrieve their memory trace, such as delayed matching to sample, serial probe recognition, etc. In contrast, how they utilize incidentally formed memory traces is not well investigated except in rodents. We examined whether domestic dogs could solve an unexpected test based on a single past experience. In Experiment 1, leashed dogs were led to 4 open, baited containers and allowed to eat from 2 of them (Exposure phase). After a walk outside for more than 10?min, during which time the containers were replaced with new identical ones, the dogs were unexpectedly returned to the site and unleashed for free exploration (test phase). Eleven out of 12 dogs first visited one of the containers from which they had not eaten. In Experiment 2, two containers had food in them, one had a nonedible object, and the last one was empty. Dogs visited all 4 containers and were allowed to eat one of the food rewards in the Exposure phase. In the test phase, unleashed dogs first visited the previously baited container from which they had not eaten significantly more often than chance. These results demonstrate that in an unexpected, test dogs may retrieve “what” and “where” information about seen (now invisible) items from incidental memory formed during a single past experience.     

Affective consequences of mere ownership: The name letter effect in twelve European languages

The hypothesis is tested that mere ownership of an object is a sufficient condition to enhance its likelihood to become one of the most attractive items of the entire set of similar objects. Evidence is presented that isolated visual letter stimuli belonging to one's own name are more often ranked among the six most preferred letters of the entire alphabet than identical not-own name letters. Across 12 different European languages, an (own) name letter effect was found for (initial and/or not-initial) letters belonging to own first and/or family name. The fundamental theoretical relevance of the effect is outlined as well as its heuristic value for research on individual versus collective ownership and on affective asymmetry. A cross-lingual analysis of the six least preferred letters-while also confirming the mere ownership hypothesis-calls for a critical reformulation of Zajonc's mere exposure theory.     

Dogs don't always prefer their owners and can quickly form strong preferences for certain strangers over others.

The unique relationship between dog and owner has been demonstrated in several experimental procedures, including tests in which dogs are left alone or with a stranger, tests of dogs’ appeasement or social approach when petted by their owner or a stranger, and their ability to learn when taught by their owner or a stranger. In all cases, dogs responded differently to their owner, which has been referred to as a specific attachment, and likely a product of a prolonged history of reinforcement. In the current study, we used a concurrent choice paradigm in which dogs could interact with two people, both of whom provided the same petting interaction, to test whether owned dogs would prefer their owner over a stranger and whether the familiarity of the testing context would influence preference. We also investigated whether shelter and owned dogs tested with two strangers would show a preference between strangers and whether that preference would be similar in magnitude to any preference between the owner and stranger. Owned dogs preferred to interact with their owners when in an unfamiliar context, but allocated more time to the stranger in a familiar context. Both shelter and owned dogs tested with two strangers showed a magnitude of preference for one stranger over the other similar to owned dogs’ preference for owners in an unfamiliar context. These results parallel what has been found in strange situation tests with owned dogs tested with their owners, but the strength of preference shown for one of two strangers indicates dogs can form a preference for one person quickly.     

The preference to work for a man or a woman: A matter of sex and gender?

A survey of 455 individuals sampled from two populations that varied in age, educational level, and work experience posed a question asked in Gallup polls over six decades: “If you were taking a new job and had your choice of a boss, would you prefer to work for a man or a woman?” Respondents could state that they would prefer a male boss, prefer a female boss, or had no preference. As expected from theory and Gallup results, respondents who had a preference preferred to work for a man more than a woman, although a majority expressed “no preference.” When they expressed a preference, women preferred to work for a female boss over a male boss more than men did, whereas men preferred to work for a male boss over a female boss more than women did. Sex-typed (i.e., masculine or feminine) respondents in gender identity exhibited a greater preference to work for a boss of a particular sex over having no preference than non-sex-typed respondents. Further, feminine respondents preferred to work for a female boss over a male boss more than masculine respondents did, whereas masculine respondents preferred to work for a male boss over a female boss more than feminine respondents did. Overall, these results suggest that the preference to work for a man or a woman is a matter of both sex and gender. Implications for job applicants' vocational decisions and how female leaders fare in the workplace are discussed.     

The best men are (not always) already taken: female preference for single versus attached males depends on conception risk

Because men of higher genetic quality tend to be poorer partners and parents than men of lower genetic quality, women may profit from securing a stable investment from the latter, while obtaining good genes via extrapair mating with the former. Only if conception occurs, however, do the evolutionary benefits of such a strategy overcome its costs. Accordingly, we predicted that (a) partnered women should prefer attached men, because such men are more likely than single men to have pair-bonding qualities, and hence to be good replacement partners, and (b) this inclination should reverse when fertility rises, because attached men are less available for impromptu sex than single men. In this study, 208 women rated the attractiveness of men described as single or attached. As predicted, partnered women favored attached men at the low-fertility phases of the menstrual cycle, but preferred single men (if masculine, i.e., advertising good genetic quality) when conception risk was high.     

The effect of food toppings on calorie estimation and consumption

In this research we examine the effect of adding a food topping to the base food on consumers' calorie estimation and consumption of the augmented food (base food plus topping). We show that consumers underestimate the calorie content of augmented food with an unhealthy base, especially when the topping is healthy. However, consumers are less likely to underestimate the calorie content of augmented food with a healthy base, regardless of whether the topping is healthy or unhealthy. Further, we show that adding a healthy topping to an unhealthy base makes consumers not only underestimate the calorie content but also eat more of the augmented food.     

Spatial memory for food hidden by rats (Rattus norvegicus) on the radial maze: studies of memory for where,what, and when

Rats (Rattus norvegicus) were allowed to hide food items on an 8-arm radial maze by carrying the items from the center to boxes at the end of each arm. Retrieval tests given after rats had hidden 4 items showed that they selectively returned to the maze arms where food had been hidden (Experiments 1 and 2). When rats were allowed to hide pieces of cheese (refed food) and pretzels (less preferred food) on different arms, they both hid and retrieved cheese before pretzels (Experiments 2-5). In Experiment 6, rats chose between arms where cheese and pretzels were hidden,with cheese degraded at one delay interval but not the other. Together, these experiments indicate memory for what and where but not when.