Evidence against integration of spatial maps in humans: generality across real and virtual environments

A real-world open-field search task was implemented with humans as an analogue of Blaisdell and Cook’s (Anim Cogn 8:7–16, 2005) pigeon foraging task and Sturz, Bodily, and Katz’s (Anim Cogn 9:207–217, 2006) human virtual foraging task to 1) determine whether humans were capable of integrating independently learned spatial maps and 2) make explicit comparisons of mechanisms used by humans to navigate real and virtual environments. Participants searched for a hidden goal located in one of 16 bins arranged in a 4 × 4 grid. In Phase 1, the goal was hidden between two landmarks (blue T and red L). In Phase 2, the goal was hidden to the left and in front of a single landmark (blue T). Following training, goal-absent trials were conducted in which the red L from Phase 1 was presented alone. Bin choices during goal-absent trials assessed participants’ strategies: association (from Phase 1), generalization (from Phase 2), or integration (combination of Phase 1 and 2). Results were inconsistent with those obtained with pigeons but were consistent with those obtained with humans in a virtual environment. Specifically, during testing, participants did not integrate independently learned spatial maps but used a generalization strategy followed by a shift in search behavior away from the test landmark. These results were confirmed by a control condition in which a novel landmark was presented during testing. Results are consistent with the bulk of recent findings suggesting the use of alternative navigational strategies to cognitive mapping. Results also add to a growing body of literature suggesting that virtual environment approaches to the study of spatial learning and memory have external validity and that spatial mechanisms used by human participants in navigating virtual environments are similar to those used in navigating real-world environments.     

The use of geometric properties of 2D arrays across development

Four- to 10-year-old children (n = 50) participated in a 2D search task that included geometry (with- and without lines) and feature conditions. During each of 27 trials, participants watched as a cartoon character hid behind one of three landmarks arranged in a triangle on a computer screen. During feature condition trials, participants could use the unique features of landmarks to locate the hidden character. During geometry condition trials the landmarks were identical, and participants had to rely on the geometric properties of the triangle they formed to locate the hidden character. In the feature condition, search accuracy was high for children of all ages. In the geometry condition (both with- and without lines), there was a sharp developmental trend in which 4-year-olds showed poor search accuracy, but performance improved with age and was at ceiling by 9- to 10-years. The presence of lines connecting the landmarks boosted performance most dramatically for the youngest children. Findings are discussed in the context of the broader literature on spatial cognition in human and non-human animals.     

Negative self-efficacy and goal effects revisited

The authors address the verification of the functional properties of self-efficacy beliefs and document how self-efficacy beliefs operate in concert with goal systems within a sociocognitive theory of self-regulation in contrast to the focus of control theory on discrepancy reduction. Social cognitive theory posits proactive discrepancy production by adoption of goal challenges working in concert with reactive discrepancy reduction in realizing them. Converging evidence from diverse methodological and analytic strategies verifies that perceived self-efficacy and personal goals enhance motivation and performance attainments. The large body of evidence, as evaluated by 9 meta-analyses for the effect sizes of self-efficacy beliefs and by the vast body of research on goal setting, contradicts findings (J. B. Vancouver, C. M. Thompson, & A. A. Williams, 2001; J. B. Vancouver, C. M. Thompson, E. C. Tischner, & D. J. Putka 2002) that belief in one's capabilities and personal goals is self-debilitating.     

Evidence against integration of spatial maps in humans

A dynamic 3-D virtual environment was constructed for humans as an open-field analogue of Blaisdell and Cook's (2005) pigeon foraging task to determine if humans, like pigeons, were capable of integrating separate spatial maps. Participants used keyboard keys and a mouse to search for a hidden goal in a 4×4 grid of raised cups. During Phase 1 training, a goal was consistently located between two landmarks (Map 1: blue T and red L). During Phase 2 training, a goal was consistently located down and left of a single landmark (Map 2: blue T). Transfer trials were then conducted in which participants were required to make choices in the presence of the red L alone. Cup choices during transfer assessed participants’ strategies: association (from Map 1), generalization (from Map 2), or integration (combining Map 1 and 2). During transfer, cup choices increased to a location which suggested an integration strategy and was consistent with results obtained with pigeons. However, additional analyses of the human data suggested participants initially used a generalization strategy followed by a progressive shift in search behavior away from the red L. This shift in search behavior during transfer was responsible for the changes in cup choices across transfer trials and was confirmed by a control condition. These new analyses offer an alternative explanation to the spatial integration account proposed for pigeons.Electronic Supplementary Material Supplementary material is available for this article at     

The effect of spatial cues on infants’ responses in the AB task,with and without a hidden object

The errors made by infants in the AB task were taken by Piaget as an indication of an inability to update their representations of the spatial location of a hidden object. This paper presents an experiment designed to further investigate the role of spatial representations in the production of the error. The introduction of strong visual cues to spatial location was found to reduce the traditional A‐not‐B search error. However, it also increased perseveration when a ‘lids‐only’ analogue of the AB task was used, in which infants are simply cued to pick up lids rather than encouraged to search for a hidden object. These results present a challenge to the dynamic systems account of the error given by Smith, Thelen, Titzer and McLin (Psychological Review, 106 (1999), 235–260), and indicate that the traditional A‐not‐B search error arises from a difficulty in updating representations of the spatial location of hidden objects. The relation of these results to Munakata’s PDP model (Developmental Science, 1 (1998), 161–211) and Thelen, Schöner, Scheier and Smith’s (Behavioural and Brain Sciences, 24 (2001), 1‐‐86) most recent dynamic systems model of the A‐not‐B error is also discussed.     

Anticipated Success at Unconscious Goal Pursuit: Consequences for Mood, Self-Esteem, and the Evaluation of a Goal-Relevant Task

This study extends recent research showing that fulfillment of unconscious goals can have the same affective consequences as fulfillment of conscious goals (T. L. Chartrand, 2001). Participants were unobtrusively primed with stimuli either relevant or irrelevant to the goal to seek knowledge. Next, an opportunity to fulfill the knowledge-seeking goal was announced (i.e., a test and subsequent feedback on a fictitious cognitive ability). As expected, participants in the knowledge-goal condition responded more positively to the announcement in terms of mood, self-esteem, and test evaluation than did participants in the no-goal condition. Consistent with a motivational account, the priming procedure did not influence mood and self-esteem when these variables were measured before test announcement.     

When logic fails: Implicit transitive inference in humans

Transitive inference (TI) in animals (e.g., choosing A over C on the basis of knowing that A is better than B and B is better than C) has been interpreted by some as reflecting a declarative logical inference process. We invert this anthropomorphic interpretation by providing evidence that humans can exhibit TI-like behavior on the basis of simpler associative mechanisms that underlie many theories of animal learning. In this study, human participants were trained on a five-pair TI problem (A+B-, B+C-, C+D-, D+E-, E+F-) and, unlike in previous human TI studies, were prevented from becoming explicitly aware of the logical hierarchy, so they could not employ logical reasoning. They were then tested with three problems: B versus D, B versus E, and C versus E. Participants only reliably chose B over E, whereas the other test conditions yielded chance performance. This result is inconsistent with the use of logical reasoning and is instead consistent with an account developed to explain earlier TI studies with rats that found the same pattern of results. In this account, choice performance is based on differential associative strengths across the stimulus items that develop over training, despite equal overt reinforcement.     

A consistent but non-coincident visual pattern facilitates the learning of spatial relations among locations

Human participants searched in a dynamic three-dimensional computer-generated virtual-environment open-field search task for four hidden goal locations arranged in a diamond configuration located in a 5 × 5 matrix of raised bins. Participants were randomly assigned to one of two groups: visual pattern or visual random. All participants experienced 30 trials in which four goal locations maintained the same spatial relations to each other (i.e., a diamond pattern), but this diamond pattern moved to random locations within the 5 × 5 matrix from trial to trial. For participants in the visual pattern group, four locations were marked in a distinct color and arranged in a diamond pattern that moved to a random location independent of the hidden spatial pattern from trial to trial throughout the experimental session. For participants in the visual random group, four random locations were marked with a distinct color and moved to random locations independent from the hidden spatial pattern from trial to trial throughout the experimental session. As a result, the visual cues for the visual pattern group were consistent but not coincident with the hidden spatial pattern, whereas the visual cues for the visual random group were neither consistent nor coincident with the hidden spatial pattern. Results indicated that participants in both groups learned the spatial configuration of goal locations and that the presence of consistent but noncoincident visual cues facilitated the learning of spatial relations among locations.     

Plans or Outcomes: How Do We Attribute Intelligence to Others?

Humans routinely make inferences about both the contents and the workings of other minds based on observed actions. People consider what others want or know, but also how intelligent, rational, or attentive they might be. Here, we introduce a new methodology for quantitatively studying the mechanisms people use to attribute intelligence to others based on their behavior. We focus on two key judgments previously proposed in the literature: judgments based on observed outcomes (you're smart if you won the game) and judgments based on evaluating the quality of an agent's planning that led to their outcomes (you're smart if you made the right choice, even if you didn't succeed). We present a novel task, the maze search task (MST), in which participants rate the intelligence of agents searching a maze for a hidden goal. We model outcome-based attributions based on the observed utility of the agent upon achieving a goal, with higher utilities indicating higher intelligence, and model planning-based attributions by measuring the proximity of the observed actions to an ideal planner, such that agents who produce closer approximations of optimal plans are seen as more intelligent. We examine human attributions of intelligence in three experiments that use MST and find that participants used both outcome and planning as indicators of intelligence. However, observing the outcome was not necessary, and participants still made planning-based attributions of intelligence when the outcome was not observed. We also found that the weights individuals placed on plans and on outcome correlated with an individual's ability to engage in cognitive reflection. Our results suggest that people attribute intelligence based on plans given sufficient context and cognitive resources and rely on the outcome when computational resources or context are limited.     

Encoding of variability of landmark-based spatial information

Recent evidence suggests humans optimally weight visual and haptic information (i.e., in inverse proportion to their variances). A more recent proposal is that spatial information (i.e., distance and direction) may also adhere to Bayesian principles and be weighted in an optimal fashion. A fundamental assumption of this proposal is that participants encode the variability of spatial information. In a three-dimensional virtual-environment open-field search task, we provide evidence that participants encoded the variability of landmark-based spatial information. Specifically, participants searched for a hidden goal location in a 5 × 5 matrix of raised bins. Participants experienced five training phases in which they searched for a hidden goal that maintained a unique spatial relationship to each of four distinct landmarks. Each landmark was assigned an a priori value of locational uncertainty such that each varied in its ability to predict a goal (i.e., varied in number of potential goal locations). Following training, participants experienced conflict trials in which two distinct landmarks were presented simultaneously. Participants preferentially responded to the landmark with the lower uncertainty value (i.e., smaller number of potential goal locations). Results provide empirical evidence for the encoding of variability of landmark-based spatial information and have implications for theoretical accounts of spatial learning.     

Hebbian learning of cognitive control: dealing with specific and nonspecific adaptation

The conflict monitoring model of M. M. Botvinick, T. S. Braver, D. M. Barch, C. S. Carter, and J. D. Cohen (2001) triggered several research programs investigating various aspects of cognitive control. One problematic aspect of the Botvinick et al. model is that there is no clear account of how the cognitive system knows where to intervene when conflict is detected. As a result, recent findings of task-specific and context-specific (e.g., item-specific) adaptation are difficult to interpret. The difficulty with item-specific adaptation was recently pointed out by C. Blais, S. Robidoux, E. F. Risko, and D. Besner (2007), who proposed an alternative model that could account for this. However, the same problem of where the cognitive system should intervene resurfaces in a different shape in this model, and it has difficulty in accounting for the Gratton effect, a hallmark item-nonspecific effect. The authors of the current article show how these problems can be solved when cognitive control is implemented as a conflict-modulated Hebbian learning rule.     

Learning HMM-based cognitive load models for supporting human-agent teamwork

Cognitive studies indicate that members of a high performing team often develop shared mental models to predict others’ needs and coordinate their behaviors. The concept of shared mental models is especially useful in the study of human-centered collaborative systems that require humans to team with autonomous agents in complex activities. We take the position that in a mixed human-agent team, agents empowered with cognitive load models of human team members can help humans develop better shared mental models to enhance team performance. Inspired by human information processing system, we here propose a HMM-based load model for members of human-agent teams, and investigate the development of realistic cognitive load models. A cognitive experiment was conducted in team contexts to collect data about the observable secondary task performance of human participants. The data were used to train hidden Markov models (HMM) with varied numbers of hypothetical hidden states. The result indicates that the model spaces have a three-layer structure. Statistical analysis also reveals some characteristics of the models at the top-layer. This study can be used in guiding the selection of HMM-based cognitive load models for agents in human-centered multi-agent systems.     

Place learning in virtual space III: Investigation of spatial navigation training procedures and their application to fMRI and clinical neuropsychology

This paper describes the utilization of a desktop virtual environment task, the Computer-Generated (C-G) Arena, in the study of human spatial navigation. First, four experiments examined the efficacy of various training procedures in the C-G Arena. In Experiment 1, participants efficiently located a hidden target after only observing the virtual environment from a fixed position (placement learning). In Experiment 2, participants efficiently located a hidden target after only observing an experimenter search the virtual environment (observational learning). In Experiment 3, participants failed to display alatent learning effect in the virtual environment. In Experiment 4, all training procedures effectively taught participants the layout of the virtual environment, but the observational learning procedure most effectivelytaught participants the location of a hidden target within the environment. Finally, two experiments demonstrated the application of C-G Arena procedures to neuroimaging (Experiment 5) and neuropsychological (Experiment 6) investigations of human spatial navigation.     

Programming tool-use actions

When humans plan to execute a tool-use action, they can only specify the bodily movement parameters by taking into account the external target or goal of the tool-use action and the target-movement mapping implemented by the tool. In this study, the authors used the movement precuing method to investigate how people prepare for actions made with tools. More specifically, they asked whether people would be able to specify the spatial target and the target-movement mapping of the tool-use action independently of each other, and to what degree they would be able to prepare these components in advance. In 3 experiments, they precued either the target or the target-movement mapping of tool-use actions involving either a compatible or an incompatible target-movement mapping. Results indicate that participants benefit from partial advance information about the target-movement mapping, whereas no significant effects were found for precuing the spatial target of the action. These results occurred regardless of whether the target-movement mapping was compatible or incompatible and provide evidence for the notion that the target-movement mapping of a tool-use action is part of its cognitive representation.     

Duties to Companion Animals

This paper outlines the moral contours of human relationships with companion animals. The paper details three sources of duties to and regarding companion animals: (1) from the animal’s status as property, (2) from the animal’s position in relationships of care, love, and dependency, and (3) from the animal’s status as a sentient being with a good of its own. These three sources of duties supplement one another and not only differentiate relationships with companion animals from wild animals and other categories of domestic animals such as livestock, but they also overlap to provide moral agents with additional reasons for preventing and avoiding harm to companion animals. The paper concludes that not only do owners and bystanders have direct and indirect duties to protect companion animals from harm, but also that these duties have the potential, in some circumstances, to clash with duties owed to the state and fellow citizens.     

A simple but powerful test of perseverative search in dogs and toddlers

Perseverative (A-not-B) errors during the search of a hidden object were recently described in both dogs and 10-month-old infants. It was found that ostensive cues indicating a communicative intent of the person who hides the object played a major role in eliciting perseverative errors in both species. However, the employed experimental set-up gave rise to several alternative explanations regarding the source of these errors. Here we present a simplified protocol that eliminates the ambiguities present in the original design. Using five consecutive object hiding events to one of two locations in a fixed order (“AABBA”), we tested adult companion dogs and human children (24 months old). The experimenter performed the hiding actions while giving ostensive cues in each trial and moved the target object to the given location in a straight line. Our results show that in the B trials, both 24-month-old children and dogs could not reliably find the hidden object, and their performance in the first B trials was significantly below that of any of the A trials. These results are the first to show that the tendency for perseverative errors in an ostensive-communicative context is a robust phenomenon among 2-year-old children and dogs, and not the by-product of a topographically elaborate hiding event.     

Memory processes in multiple-target visual search

Gibson, Li, Skow, Brown, and Cooke (Psychological Science, 11, 324-327, 2000) had participants carry out a search task in which they were required to detect the presence of one or two targets. In order to successfully perform such a multiple-target visual search task, participants had to remember the location of the first target while searching for the second target. In two experiments we investigated the cost of remembering this target location. In Experiment 1, we compared performance on the Gibson et al. task with performance on a more conventional present-absent search task. The comparison suggests a substantial performance cost as measured by reaction time, number of fixations and slope of the search functions. In Experiment 2, we looked in detail at refixations of distractors, which are a direct measure of attentional deployment. We demonstrated that the cost in this multiple-target visual search task was due to an increased number of refixations on previously visited distractors. Such refixations were present right from the start of the search. This change in search behaviour may be caused by the necessity of having to remember a target-allocating memory for the upcoming target may consume memory capacity that may otherwise be available for the tagging of distractors. These results support the notion of limited capacity memory processes in search.     

Thinking Without Words: An Overview for Animal Ethics

In Thinking without Words I develop a philosophical framework for treating some animals and human infants as genuine thinkers. This paper outlines the aspects of this account that are most relevant to those working in animal ethics. There is a range of different levels of cognitive sophistication in different animal species, in addition to limits to the types of thought available to non-linguistic creatures, and it may be important for animal ethicists to take this into account in exploring issues of moral significance and the obligations that we might or might not have to non-human animals. I am grateful for comments on an earlier version from Robert Francescotti and Clare Palmer.     

Aging and the Development of Automaticity in Feature Search

A training experiment was conducted to investigate age differences in the learning that occurs when observers search for an orientation-defined target among a homogeneous set of distractors (i.e., feature search). Eighteen young (M age = 26 years) and seventeen old (M age = 62 years) participants completed seven practice sessions (3,024 trials), followed by a single session of full reversal. Training involved consistent mapping, varied mapping, or nonsearch, in which a precue predicted the target location with 100% validity. Younger and older observers demonstrated equivalent learning rates and equivalent disruption following reversal in all training conditions. Results are interpreted within models of visual attention and search.