Transposition of flower height by bumble bee foragers (Bombus impatiens)

Honeybees learn visual characteristics of reinforced and non-reinforced flowers in differential conditioning experiments (i.e., experiments that require subjects to choose between a reinforced and non-reinforced flower). In this study bumble bee foragers (Bombus impatiens) were trained in a transposition paradigm to determine if the relational properties of flowers also influence choice behavior. Subjects in one group (group A) were trained with repeated choices between a medium-height flower replete with sucrose solution and an empty tall flower until the medium-height flower was sampled preferentially in five consecutive trials. A second group (group B) was trained on the medium height flower alone for five trials. In a single test trial subjects were given a choice between the medium-height flower and a short flower, each filled with water. A control group showed no preference in this test. Group B subjects showed a significant preference for the medium-height flower and group A subjects that exhibited flower constancy (i.e., sampled only the medium-height flower in training trials) showed an identical pattern of choice. Subjects in group A that sampled both flowers during training, in contrast, transposed flower height and preferred the short flower. These results suggest that the choice behavior of bumble bee foragers is influenced by relational and absolute properties of flowers. The flower characteristics learned by foragers appear to depend on the difficulty of the discrimination problem and the context in which flowers are sampled. Patches of flowers limited in phenotypic variability may produce simple associative learning and flower constancy by foragers. Received: 17 September 1999 / Accepted after revision: 22 June 2000     

Does the brain calculate value?

How do people choose between options? At one extreme, the 'value-first' view is that the brain computes the value of different options and simply favours options with higher values. An intermediate position, taken by many psychological models of judgment and decision making, is that values are computed but that the resulting choices depend heavily on the context of available options. At the other extreme, the 'comparison-only' view argues that choice depends directly on comparisons, with or even without any intermediate computation of value. In this paper, we place past and current psychological and neuroscientific theories on this spectrum, and review empirical data that have led to an increasing focus on comparison rather than value as the driver of choice.     

Honeybee methodology, cognition, and theory: recording local directional decisions in interpatch foraging and interpreting their theoretical relevance

Investigations made into the cognitive decision making of honeybees (Apis mellifera) traveling from one flower patch to another flower patch (interpatch foraging) are few. To facilitate such research, we present methods to artificially emulate interpatch foraging and quantify the immediate decision making of honeybees (within 50 cm) choosing to fly an interpatch path. These “Interpatch Methods” are validated, applied, and shown to produce novel information for the field of honeybee spatial cognition. Generally, we demonstrate that a single foraging cohort of honeybees is shown to be capable of making decisions based upon different sets of learned cues, in the exact same context. Specifically, both terminal beacon orientation cues and compass navigation cues can guide the cognitive decision making of interpatch foraging honeybees; our bees chose both cues equally. Finally, the theoretical importance of decision making for interpatch paths is compared with the other foraging paths (outward and homing) with respect to the information available to recruited foragers and scout foragers. We conclude that the ability to analyze interpatch foraging is critical for a more complete understanding of honeybee foraging cognition and that our methods are capable of providing that understanding.     

Decision ecology: Foraging and the ecology of animal decision making

In this article, I review the approach taken by behavioral ecologists to the study of animal foraging behavior and explore connections with general analyses of decision making. I use the example of patch exploitation decisions in this article in order to develop several key points about the properties of naturally occurring foraging decisions. First, I argue that experimental preparations based on binary, mutually exclusive choice are not good models of foraging decisions. Instead, foraging choices have a sequential foreground-background structure, in which one option is in the background of all other options. Second, behavioral ecologists view foraging as a hierarchy of decisions that range from habitat selection to food choice. Finally, data suggest that foraging animals are sensitive to several important trade-offs. These trade-offs include the effects of competitors and group mates, as well as the problem of predator avoidance.     

Eye Movements in Risky Choice

We asked participants to make simple risky choices while we recorded their eye movements. We built a complete statistical model of the eye movements and found very little systematic variation in eye movements over the time course of a choice or across the different choices. The only exceptions were finding more (of the same) eye movements when choice options were similar, and an emerging gaze bias in which people looked more at the gamble they ultimately chose. These findings are inconsistent with prospect theory, the priority heuristic, or decision field theory. However, the eye movements made during a choice have a large relationship with the final choice, and this is mostly independent from the contribution of the actual attribute values in the choice options. That is, eye movements tell us not just about the processing of attribute values but also are independently associated with choice. The pattern is simple—people choose the gamble they look at more often, independently of the actual numbers they see—and this pattern is simpler than predicted by decision field theory, decision by sampling, and the parallel constraint satisfaction model. © 2015 The Authors. Journal of Behavioral Decision Making published by John Wiley & Sons Ltd.     

The dynamics of deferred decision

Decision makers are often unable to choose between the options that they are offered. In these settings they typically defer their decision, that is, delay the decision to a later point in time or avoid the decision altogether. In this paper, we outline eight behavioral findings regarding the causes and consequences of choice deferral that cognitive theories of decision making should be able to capture. We show that these findings can be accounted for by a deferral-based time limit applied to existing sequential sampling models of preferential choice. Our approach to modeling deferral as a time limit in a sequential sampling model also makes a number of novel predictions regarding the interactions between choice probabilities, deferral probabilities, and decision times, and we confirm these predictions in an experiment. Choice deferral is a key feature of everyday decision making, and our paper illustrates how established theoretical approaches can be used to understand the cognitive underpinnings of this important behavioral phenomenon.     

Development of decision making: sequential versus integrative rules

Decisions can be made by applying a variety of decision-making rules-sequential rules in which decisions are based on a sequential evaluation of choice dimensions and the integrative normative rule in which decisions are based on an integration of choice dimensions. In this study, we investigated the developmental trajectory of such decision-making rules. In the Gambling Machine Task, participants choose between options that differ in three dimensions: frequency of loss, amount of loss, and certain gain. The task was administered to 231 children and adolescents (age range=8-17 years). Latent group analysis of their performance allowed precise classification of the underlying decision rules. The majority of participants used sequential decision rules, and the number of evaluated dimensions in these rules increased with age. Integrative rule use decreased with age. We discuss these results in light of traditional developmental theories and fuzzy trace theory.     

Goal attainment as a resource: The cushion effect in risky choice above a goal

Goals are a ubiquitous part of life and have been shown to change behavior in many domains. This research studied the influence of goal attainment on risky choice behavior. Previous research has shown that goals tend to increase risk‐seeking behavior when potential outcomes fall below a goal. We examined a new problem: Choice behavior when all potential outcomes in a choice set achieve or exceed the goal. Two studies show a “cushion effect” of goal attainment on choice under risk. When all possible outcomes of all options are above a salient and specific goal, decision makers are more likely to choose a risky option over a certain outcome with equal expected value (EV). We hypothesized that the attainment of a goal serves as a cushion that softens the negative emotions associated with receiving a gamble's low outcome. This allows risk taking that would otherwise be unattractive. Copyright © 2009 John Wiley & Sons, Ltd.     

The effects of genotype, foraging role, and sucrose responsiveness on the tactile learning performance of honey bees (Apis mellifera L.)

We analyzed sucrose responsiveness and associative tactile learning in two genetic strains of honey bees under laboratory conditions. These strains differ in their foraging behavior. Bees of the "high" strain preferentially collect pollen. "Low"-strain bees mainly forage for nectar. Responsiveness to different sucrose concentrations and tactile learning were examined using the proboscis extension reflex. Acquisition, extinction of conditioned responses, and responses to an alternative tactile stimulus were tested. High-strain bees are more responsive to sucrose than low-strain bees. Regardless of genotype, pollen foragers are more responsive to sucrose than nectar foragers. In bees of both strains we find the same relationship between responsiveness to sucrose and acquisition. Bees responding to low sucrose concentrations show more often the conditioned response during acquisition than those responding only to higher sucrose concentrations. Extinction of conditioned responses depends on the response probability during acquisition. Discrimination between the two tactile stimuli is affected by genotype but not by responsiveness to sucrose. High-strain bees discriminate better than low-strain bees. Our experiments thus establish links between division of labor, responsiveness to sucrose, and associative learning in honey bees.     

Evidence for associative learning in newly emerged honey bees (Apis mellifera)

The honey bee is a model organism for studies on the neural substrates of learning and memory. Associative olfactory learning using sucrose rewards is fast and reliable in foragers and older hive bees. However, researchers have so far failed to show any significant learning in newly emerged bees. It is generally argued that in these bees only part of the brain structures important for learning are fully developed. Here we show for the first time that newly emerged honey bees are capable of associative learning, if they are sufficiently responsive to sucrose. Responsiveness to sucrose, which can be measured using the proboscis extension response (PER), increases with age. Newly emerged bees are on average very unresponsive to sucrose. We show that if newly emerged bees displaying a PER to 10% sucrose or lower sucrose concentrations are conditioned to an odour, they show significant associative learning and early long-term memory. Nevertheless, the level of acquisition is still lower than in foragers. The general assumption that newly emerged honey bees are incapable of associative learning must therefore be reconsidered. Further, our study suggests that an age-dependent increase in responsiveness to rewarding stimuli is directly related to the development of early learning abilities. The decisive influence of responsiveness to rewarding stimuli in associative learning of newly emerged bees has far reaching consequences for studies on the development of associative learning capabilities in insects and vertebrates.     

The impact of phantom decoys on choices in cats

Context-dependent choice is an important aspect of decision making. The paper examines context-dependent choice in cats (Felis catus), with particular reference to the effect of local context, on the basis of hypotheses developed in the field of human decision making. Cats were initially confronted with two different feeding options. This binary choice set was later manipulated incorporating a decoy that was better than the available options but ultimately unavailable (a phantom). By means of a within-subjects manipulation of phantom location in the attribute space, the author compared the effects of close and distant phantoms on the final choices. The main finding is that close phantom decoys affected choice behavior of cats by altering the overall share of the available options, leading some animals to reject even some of the available feeding options, and by causing the animals to favor the available option that was more similar to the phantom decoy. No significant effects emerged for phantoms that were far from the alternatives in the attribute space. The strengths of this paper lie in its novel approach and high originality. No other study has used dominating decoys with animals or decoys that are unattainable. This paper provides strong links to the human decision making literature, the presentation of the predictions of a range of different choice models, and the novelty of the application to animals. The use of a phantom decoy is particularly interesting because the phantom cannot actually be chosen, and thus the binary and trinary choice sets both have the very same choices available. Overall, the effect of phantoms is real, interesting and new.     

The cognitive and neural basis of option generation and subsequent choice

Decision-making research has thoroughly investigated how people choose from a set of externally provided options. However, in ill-structured real-world environments, possible options for action are not defined by the situation but have to be generated by the agent. Here, we apply behavioral analysis (Study 1) and functional magnetic resonance imaging (Study 2) to investigate option generation and subsequent choice. For this purpose, we employ a new experimental task that requires participants to generate options for simple real-world scenarios and to subsequently decide among the generated options. Correlational analysis with a cognitive test battery suggests that retrieval of options from long-term memory is a relevant process during option generation. The results of the fMRI study demonstrate that option generation in simple real-world scenarios recruits the anterior prefrontal cortex. Furthermore, we show that choice behavior and its neural correlates differ between self-generated and externally provided options. Specifically, choice between self-generated options is associated with stronger recruitment of the dorsal anterior cingulate cortex. This impact of option generation on subsequent choice underlines the need for an expanded model of decision making to accommodate choice between self-generated options.     

Differences in performance on a reversal learning test and division of labor in honey bee colonies

We studied the association between honey bee (Apis mellifera) division of labor and performance on an olfactory reversal-learning test. Manipulations of colony age structure and flight experience were used to test whether differences in performance are associated with age, current behavioral state, or flight experience. Nurse bees showed significantly faster rates of extinction to a learned odor than did foragers. This difference was associated primarily with differences in behavioral state, rather than age; it was seen when comparing nurses and foragers from typical colonies and normal-age nurses and precocious foragers from single-cohort colonies. Differences in extinction rate were not related to differences in flight experience; there was no difference between foragers and foraging-age bees denied flight experience. These results suggest that changes in learning and memory occur in association with division of labor. We speculate on the possible functional significance of the difference in extinction rate between nurses and foragers. Received: 15 January 2000 / Accepted: 22 August 2000     

A dynamic, stochastic, computational model of preference reversal phenomena

Preference orderings among a set of options may depend on the elicitation method (e.g., choice or pricing); these preference reversals challenge traditional decision theories. Previous attempts to explain these reversals have relied on allowing utility of the options to change across elicitation methods by changing the decision weights, the attribute values, or the combination of this information--still, no theory has successfully accounted for all the phenomena. In this article, the authors present a new computational model that accounts for the empirical trends without changing decision weights, values, or combination rules. Rather, the current model specifies a dynamic evaluation and response process that correctly predicts preference orderings across 6 elicitation methods, retains stable evaluations across methods, and makes novel predictions regarding response distributions and response times.     

Collecting information: Optimizing outcomes, screening options, or facilitating discrimination?

Collection of information prior to a decision may be integrated into a compensatory choice process; if it is, the information packet that is collected should be the one that produces the highest net gain. Alternatively,information may be collected in order to screen out options that fail to meet minimum standards; if this is the case, people should not choose options on which they have not collected available information. We tested these and other predictions from the two approaches in four experiments. Participants were given specific information about three attributes of each choice option but only probabilistic information about a fourth one. They rated attractiveness of options, decidedwhether to collect specific information about the fourth attribute of each one, rated options again, and then selected one of them. Data were consistent with neither of the above approaches. Instead they suggested that people collect information in order to facilitate their ability to discriminate between the attractiveness of options.     

Do inexperienced bumblebee foragers use scent marks as social information?

Bumblebees (Bombus spp.) foraging in the field typically reject flowers where they detect the olfactory footprints of previous visitors and hence avoid recently emptied inflorescences. A growing number of studies have begun to illustrate that associative learning shapes the development of this process, in both bumblebees and other bee species. This raises the question of what the default response to such marks is, but little is known about how inexperienced foragers use social information. Here, we offered flower-naive bees a choice between scent-marked flowers and unmarked alternatives and found that individuals neither avoided nor preferred marked flowers. Our findings provide no support for ‘hard-wired’ responses to scent marks in bumblebees and highlight the importance of associative learning in shaping social information use to match local circumstances.     

Self–other differences in multiattribute decision making: Compensatory versus noncompensatory decision strategies

When making decisions where options involve multiple attributes, a person can choose to use a compensatory, utility maximizing strategy, which involves consideration and integration of all available attributes. Alternatively, a person can choose a noncompensatory strategy that extracts only the most important and reliable attributes. The present research examined whether other‐oriented decisions would involve greater reliance on a noncompensatory, lexicographic decision strategy than self‐oriented decisions. In three studies (Mturk workers and college students), the difference in other‐oriented versus self‐oriented decisions in a medical decision context was explained by a subsample of participants that chose the death minimizing operation on all 10 decisions (Study 1) and a subsample of participants who self‐reported that they used a strategy that minimized the chance of death on every decision (i.e., a lexicographic mortality heuristic; Study 2). In Study 2, tests of mediation found that self‐reported use of the mortality heuristic completely accounted for the self–other effect on decisions. In Study 3, participants were more likely to report prospectively that they would adopt the mortality heuristic when making decisions for others than for themselves, suggesting that participants were not mistakenly inferring a lexicographic decision strategy from their past behavior. The results suggest that self–other effects in multiattribute choice involve differential use of compensatory versus noncompensatory decision strategies and that beyond this group difference, individual differences in the use of these strategies also exist within self‐oriented and other‐oriented decisions.     

Decision-making competence in younger and older adults: which cognitive abilities contribute to the application of decision rules?

Older adults perform worse than younger adults when applying decision rules to choose between options that vary along multiple attributes. Although previous studies have shown that general fluid cognitive abilities contribute to the accurate application of decision rules, relatively little is known about which specific cognitive abilities play the most important role. We examined the independent roles of working memory, verbal fluency, semantic knowledge, and components of executive functioning. We found that age-related decline in applying decision rules was statistically mediated by age-related decline in working memory and verbal fluency. Our results have implications for theories of aging and decision-making.