Tracking objects that move where they are headed

Previous work has demonstrated that the ability to keep track of moving objects is improved when the objects have unique visual features, such as color or shape. In the present study, we investigated how orientation information is used during the tracking of objects. Orientation is an interesting feature to explore in moving objects because it is directional and is often informative of the direction of motion. Most objects move forward, in the direction they are oriented. In the present experiments, participants tracked a subset of moving isosceles triangles whose orientations were constant, related, or unrelated to the direction of motion. In the standard multiple object tracking (MOT) task, tracking performance improved when orientations were unique and remained constant, but not when orientation and direction of motion were aligned. In the target recovery task, in which MOT was interrupted by a brief blanking of the display, performance did improve when orientation and direction were aligned. In the final experiment, results showed that orientation was not used before the blank to predict future target locations, but was instead used after the blank. We concluded that people use orientation to compare a stored representation to target position for recovery of lost targets.     

Proper names and how they are learned

Abstract

Proper names function in our conceptual lives as means for denoting individuals in kinds. Kinds are denoted by common names, more precisely count nouns, and so there are important interrelations between proper names and common nouns. All of this shows up in the way we interpret proper names and employ them in everyday inferences. For example, an airline may count three passengers in relation to a single person Jane, if Jane takes three trips with the airline. Each of the three passengers is Jane, but there is only one Jane. To handle such operations we propose a theory of proper names as part of the theory of kinds. This enables us to specify certain resources (some of them unlearned) that are necessary for the learning of proper names and also a theory of how they are learned. We review the experimental literature on the learning of proper names from the standpoint of the theory. We do not extend the theory to cover recognition or recall.     

Changes are not localized before they are explicitly detected

Change detection is in many ways analogous to visual search. Yet, unlike search, successful detection depends not on the salience of features within a scene, but on the difference between the original and modified scene. If, as in search, pre-attentive mechanisms guide attention to the change location, the change itself must produce a preattentively detectable signal. Despite recent evidence for implicit representation of change in the absence of conscious detection, few studies have yet explored whether attention is guided to a change location prior to explicit detection. In four “change blindness” experiments using several variants of the “flicker” task, we tested the hypothesis that implicit or preattentive mechanisms guide change localization prior to explicit detection. None of the experiments revealed improved localization of changes prior to explicit reports of detection, suggesting that implicit detection of change does not contribute to the eventual explicit localization of a change. Instead, change localization is essentially arbitrary, driven by the salience of features within scenes.     

Chimpanzees (Pan troglodytes) know what can be seen from where

Visual perspective taking research has established that chimpanzees recognize what others can or cannot see in the presence of occluding barriers. Less is known about chimpanzees’ appreciation of what they themselves can or cannot see in similar situations. Additionally, it is unclear whether chimpanzees must rely on others’ gaze cues to solve such tasks or whether they have a more general appreciation of what can be seen from where. Hence, we investigated chimpanzees’ ability to anticipate what they would or would not be able to see from different visual perspectives. Food was hidden among arrays of open containers, with different containers providing visual access from unique viewing perspectives. Chimpanzees immediately adopted the correct perspective for each container type. Follow-up experiments showed that they were not simply moving to align themselves with visible openings. Our study thus suggests that chimpanzees have good visual perspective taking abilities with regard to themselves as well as others, and that both likely reflect a more general knowledge, at least implicit, of what can be seen from where.

Prototypes are attractive because they are easy on the mind

People tend to prefer highly prototypical stimuli--a phenomenon referred to as the beauty-in-averageness effect. A common explanation of this effect proposes that prototypicality signals mate value. Here we present three experiments testing whether prototypicality preference results from more general mechanisms-fluent processing of prototypes and preference for fluently processed stimuli. In two experiments, participants categorized and rated the attractiveness of random-dot patterns (Experiment 1) or common geometric patterns (Experiment 2) that varied in levels of prototypicality. In both experiments, prototypicality was a predictor of both fluency (categorization speed) and attractiveness. Critically, fluency mediated the effect of prototypicality on attractiveness, although some effect of prototypicality remained when fluency was controlled. The findings were the same whether or not participants explicitly considered the pattern's categorical membership, and whether or not categorization fluency was salient when they rated attractiveness. Experiment 3, using the psychophysiological technique of facial electromyography, confirmed that viewing abstract prototypes elicits quick positive affective reactions.     

Representation facilitates reasoning: what natural frequencies are and what they are not

A good representation can be crucial for finding the solution to a problem. Gigerenzer and Hoffrage (Psychol. Rev. 102 (1995) 684; Psychol. Rev. 106 (1999) 425) have shown that representations in terms of natural frequencies, rather than conditional probabilities, facilitate the computation of a cause's probability (or frequency) given an effect--a problem that is usually referred to as Bayesian reasoning. They also have shown that normalized frequencies--which are not natural frequencies--do not lead to computational facilitation, and consequently, do not enhance people's performance. Here, we correct two misconceptions propagated in recent work (Cognition 77 (2000) 197; Cognition 78 (2001) 247; Psychol. Rev. 106 (1999) 62; Organ. Behav. Hum. Decision Process. 82 (2000) 217): normalized frequencies have been mistaken for natural frequencies and, as a consequence, "nested sets" and the "subset principle" have been proposed as new explanations. These new terms, however, are nothing more than vague labels for the basic properties of natural frequencies.     

A cognitive-psychological perspective on Gillespie's "Lights and lattices": some relations among perception, imagery, and thought

George Gillespie's valuable observations on light and lattice imageries are played in the context of current research and theory on cognitive imagery (Kosslyn, Pylyshyn), ordinary and lucid dreaming, representational geometric imagery in scientific thought, the author's previous writings on altered states of consciousness, and Gibson's views on perception and imagery. Gillespie's reports show categories of imagery deconstruction and abstraction that link these areas and suggest an integrative model of the varieties of symbolic imagery.     

Instrumentality boosts appreciation: helpers are more appreciated while they are useful

We propose that in social interactions, appreciation of a helper depends on that helper's instrumentality: The more motivated one is to accomplish a goal, and the more one perceives a helper as able to facilitate that goal, the more appreciation one will feel for that helper. Four experiments supported this instrumentality-boost hypothesis by showing that beneficiaries felt more appreciation of their helpers while they were receiving help toward an ongoing task than after that task was completed or after the helper was deemed no longer instrumental. This finding held for both the positive side of appreciation (gratitude) and the negative side (feelings of indebtedness) and also across a range of relationships (complete strangers, newly acquainted partners, and friends). This pattern of appreciation is counterintuitive for helpers, and so a mismatch arises between the time courses of beneficiaries' experienced appreciation and helpers' expectations of appreciation.     

Getting scientists to think about what they are doing

Research scientists are trained to produce specialised bricks of knowledge, but not to look at the whole building. Increasing public concern about the social role of science is forcing science students to think about what they are actually learning to do. What sort of knowledge will they be producing, and how will it be used? Science education now requires serious consideration of these philosophical and ethical questions. But the many different forms of knowledge produced by modern science cannot be covered by any single philosophical principle. Sociology and cognitive psychology are also needed to understand what the sciences have in common and the significance of what they generate. Again, traditional modes of ethical analysis cannot deal adequately with the values, norms and interests activated by present-day technoscience without reference to its sociological, political and economic dimensions. What science education now requires is ‘metascience’, a discipline that extends beyond conventional philosophy and ethics to include the social and humanistic aspects of the scientific enterprise. For example, students need to learn about the practices, institutions, career choices, and societal responsibilities of research scientists, and to rehearse in advance some of the moral dilemmas that they are likely to meet. They need also to realise that science is changing rapidly, not only in its research techniques and organisational structures but also in its relationships with society at large.     

People believe that they are prototypically good or bad

People have been shown to view their beliefs as being prototypical (modal) but their abilities as (falsely) unique (above or below average). It is possible that these two viewpoints – self as prototypical and self as unique – can be reconciled. If the distribution of ability for a given skill is skewed such that many others have high (low) ability and few others have low (high) ability, it is possible that a majority of peoples’ self-assessments can be above (below) average. Participants in 5 studies demonstrated an understanding that various skills have skewed ability distributions and their self-assessments were related to distribution shape: high when negatively skewed and low when positively skewed. Further, participants tended to place themselves near the mode of their perceived skill distribution. Participants were most likely to think that they were good at skills for which they thought that most others were also good.     

Who they are and what de se: Burge on quasi-memory

Tyler Burge has recently argued that quasi-memory-based psychological reductionist accounts of diachronic personal identity are deeply problematic. According to Burge, these accounts either fail to include appropriately de se elements or presuppose facts about diachronic personal identity—facts of the very kind that the accounts are supposed to explain. Neither of these objections is compelling. The first is based in confusion about the version of reductionism to which it putatively applies. The second loses its force when we recognize that reductionism is a metaphysical thesis, not an epistemological one.

High-restrained eaters only overeat when they are also impulsive

Recent work shows that the inability to inhibit basic motor responses (like pressing a button) is related to overeating, weight gain and overweight. In the present study it was tested whether this inability to inhibit motor responses - or impulsivity - can differentiate between successful and unsuccessful restrained eaters. A typical preload and food exposure paradigm was used and it was hypothesized that only the high-restrained eaters that are simultaneously inefficient inhibitors of prepotent motor responses would overeat when confronted with tempting foods. In line with the hypothesis, the data show that overeating follows from an interaction between restraint and impulsivity; high-restrained eaters only overate when they were also impulsive. It is concluded that being restrained per se is not a determinant of overeating. Being a restrained eater only bears the risk of overeating in case of coexisting impulsivity.     

Computer viruses: What they are,how they work,how they might get you,and how to control them in academic institutions

A computer virus is a program that replicates itself and spreads to computers with the goal of disrupting or destroying normal computer use. In academic computing, viruses represent a serious problem that costs millions of dollars in losses annually and hinders the free exchange of information so critical to education. Viruses operate in incubation, infection, and destroy phases. The nature, mechanisms, and preventive measures for personal-computer viruses are reviewed. Different procedures are recommended to protect research laboratories, instructional laboratories, and software lending libraries. Tradeoffs between providing adequate protection and not having the security become too burdensome are considered.     

The bigger they are, the harder they fall: Linking team power, team conflict, and performance

Across two field studies, we investigate the impact of team power on team conflict and performance. Team power is based on the control of resources that enables a team to influence others in the company. We find across both studies that low-power teams outperform high-power teams. In both studies, higher levels of process conflict present in high-power teams explain this effect fully. In our second study, we show that team interpersonal power congruence (i.e., the degree to which team members’ self-views of their individual power within the team align with the perceptions of their other team members) ameliorates the relationship between team power and process conflict, such that when team interpersonal power congruence is high, high-power teams are less likely to experience performance-detracting process conflict.     

Dealing with conflicting information: young children's reliance on what they see versus what they are told

Children often learn about the world through direct observation. However, much of children's knowledge is acquired through the testimony of others. This research investigates how preschoolers weigh these two sources of information when they are in conflict. Children watched as an adult hid a toy in one location. Then the adult told children that the toy was in a different location (i.e. false testimony). When retrieving the toy, 4- and 5-year-olds relied on what they had seen and disregarded the adult's false testimony. However, most 3-year-olds deferred to the false testimony, despite what they had directly observed. Importantly, with a positive searching experience based on what they saw, or with a single prior experience with an adult as unreliable, 3-year-olds subsequently relied on their first-hand observation and disregarded the adult's false testimony. Thus, young children may initially be credulous toward others' false testimony that contradicts their direct observation, but skepticism can develop quickly through experience.     

Graphemes evoke synesthetic colors even before they are consciously recognized

We showed a grapheme-color synesthete three different examples of stimuli in which the graphemes were 'hidden'--as in puzzle pictures--and became visible as letters only after prolonged viewing. Intriguingly the subject saw the appropriate colors accurately long before the graphemes became consciously visible--a novel form of blindsight.     

Associative changes in excitors and inhibitors differ when they are conditioned in compound

When an AB stimulus compound is reinforced or nonreinforced, there are associative changes in both A and B elements. In many contemporary theories those changes are viewed as governed by a common error term, computed as the discrepancy between the total associative strength of the AB compound and that supported by the trial consequence. This implies that if A and B are equally salient, then the magnitude of their associative change should be the same, whatever their strengths prior to the AB trial. This implication was explored for a compound consisting of an excitatory A and an inhibitory B. A novel assessment procedure avoided the difficulty of making comparisons at different locations on the performance scale. Three experiments using a magazine approach preparation in rats and 3 using autoshaping in pigeons found evidence contradicting this implication. The excitatory A changed less than the inhibitory B when the compound was reinforced but more than B when the compound was nonreinforced.