Advantage of dichromats over trichromats in discrimination of color-camouflaged stimuli in humans

This study investigated whether 12 participants with color-vision deficiency had superior visual discrimination of color-camouflaged stimuli shown on a computer screen compared with 12 participants with normal trichromatic vision. Participants were asked to distinguish a circular pattern from other patterns in which textural elements differed from the background in orientation and thickness. In one condition, stimuli were single-colored, green or red; in the other condition, stimuli were color camouflaged with a green and red mosaic overlaid onto the pattern. Color-vision deficient participants selected the correct stimuli in the color-camouflaged condition as quickly as they did in the single-colored condition. However, normal color-vision participants took longer to select the correct choice in the color-camouflaged condition than in the single-colored condition. These results suggest that participants with color-vision deficiency may have a superior visual ability to discriminate the color-camouflaged stimuli.     

A Sensory Origin for Color-Word Stroop Effects in Aging: Simulating Age-Related Changes in Color-vision Mimics Age-Related Changes in Stroop

ABSTRACT

An increase in Stroop effects with age can be interpreted as reflecting age-related reductions in selective attention, cognitive slowing, or color-vision. In the present study, 88 younger adults performed a Stroop test with two color-sets, saturated and desaturated, to simulate an age-related decrease in color perception. This color manipulation with younger adults was sufficient to lead to an increase in Stroop effects that mimics age-effects. We conclude that age-related changes in color perception can contribute to the differences in Stroop effects observed in aging. Finally, we suggest that the clinical applications of Stroop take this factor into account.     

A sensory origin for color-word stroop effects in aging: simulating age-related changes in color-vision mimics age-related changes in Stroop

An increase in Stroop effects with age can be interpreted as reflecting age-related reductions in selective attention, cognitive slowing, or color-vision. In the present study, 88 younger adults performed a Stroop test with two color-sets, saturated and desaturated, to simulate an age-related decrease in color perception. This color manipulation with younger adults was sufficient to lead to an increase in Stroop effects that mimics age-effects. We conclude that age-related changes in color perception can contribute to the differences in Stroop effects observed in aging. Finally, we suggest that the clinical applications of Stroop take this factor into account.     

The demonstration of capacity limitation

The study of divided attention has produced many apparent demonstrations of “capacity limitation.” Possible ambiguities in such demonstrations are considered for three major types of experimental situation: simultaneous inputs with separate responses; choice; and classification. Two issues emerge. First, demonstrations always rest on assumptions about process set, i.e., the set of internal processes by which the task actually is performed. Alternative process sets are considered for situations of each type. Second, a demonstration of capacity limitation is made either by increasing the number of simultaneous processes, or by changing the bias between them. In either case effects unrelated to capacity limitation may influence the results. If several processes contribute to a single response, some performance decrement must accompany an increase in their number, simply through the increased overall chance for error. If the subject is biased toward one alternative in a choice or classification situation, the benefits enjoyed by this alternative may reflect not a preferential allocation of attentional capacity, but simply a willingness to decide in favor of this alternative with relatively little evidence.     

Perception: A HyperCard stack for demonstrating visual perceptual phenomena

Perception is a HyperCard stack that allows users to explore visual illusions and other perceptual phenomena on the Apple Macintosh. The stack contains over 20 demonstrations of intersecting line illusions, size and shape illusions, subjective contours, color assimilation, and so forth. As a presentation tool for classroom or laboratory demonstrations, Perception offers three unique features for displaying visual phenomena: (1) the capability to “dissolve” the inducing elements of an illusion in order to show the objective state of affairs, (2) the ability to quickly reverse the inducing elements of an illusion and therefore the effects of the distortion, and (3) animation of the various components of an illusion to produce continuous distortions in-real time. These features are illustrated with use of the Orbison, Titchener, Hering, and Wundt illusions. Use of the stack reveals two interesting and unanticipated findings: (1) an apparent size distortion in the central square of the Orbison illusion as it moves back and forth across the background of concentric rings, and (2) perceptual aftereffects that arise when the inducing elements of the Titchener, Hering, or Wundt illusion is dissolved.     

Neural Policy Style Transfer

Style Transfer has been proposed in a number of fields: fine arts, natural language processing, and fixed trajectories. We scale this concept up to control policies within a Deep Reinforcement Learning infrastructure. Each network is trained to maximize the expected reward, which typically encodes the goal of an action, and can be described as the content. The expressive power of deep neural networks enables encoding a secondary task, which can be described as the style. The Neural Policy Style Transfer (NPST)¹ algorithm is proposed to transfer the style of one policy to another, while maintaining the content of the latter. Different policies are defined via Deep Q-Network architectures. These models are trained using demonstrations through Inverse Reinforcement Learning. Two different sets of user demonstrations are performed, one for content and other for style. Different styles are encoded as defined by user demonstrations. The generated policy is the result of feeding a content policy and a style policy to the NPST algorithm. Experiments are performed in a catch-ball game inspired by the Deep Reinforcement Learning classical Atari games; and a real-world painting scenario with a full-sized humanoid robot, based on previous works of the authors. The implementation of three different Q-Network architectures (Shallow, Deep and Deep Recurrent Q-Network) to encode the policies within the NPST framework is proposed and the results obtained in the experiments with each of these architectures compared.     

Autonomy support enhances performance expectancies,positive affect,and motor learning

ObjectivesAccording to the OPTIMAL theory of motor learning (Wulf & Lewthwaite, 2016), autonomy support contributes to successful performance and learning in part by enhancing learners' expectancies. The present study was designed to test expectancy-related predictions. Specifically, we examined the effects of practice with autonomy support on learners’ self-efficacy, positive affect, and thoughts during practice.DesignExperimental study with two groups. Movement form was assessed in two different experimental phases, supplemented by questionnaire data.MethodTen-year old children were shown a sequence of 5 ballet positions they were asked to learn: Preparatory position, demi plié, tendu with arms and legs in second position, passé with arms in first position, and elevé with feet in first position. In the autonomy-support (AS) group, participants were able to choose video demonstrations throughout practice, while control (C) group participants were provided with demonstrations based on their yoked counterparts’ choices. One day after practice, participants performed in a retention test.ResultsThe AS group demonstrated greater improvements in movement form during practice and enhanced learning relative to the C group. Furthermore, AS participants had higher self-efficacy and greater positive affect than the C group. Also, AS participants reported having more positive thoughts during practice relative to C group participants, who reported more negative and self-related thoughts.ConclusionsThe present findings are in line with OPTIMAL theory predictions. They highlight the motivational underpinnings of the learning benefits that are seen when learners are given choices.     

The hidden face of Kanizsa's triangle: apparent movement of subjective figures in three-dimensional space

Several demonstrations on the apparent movement in depth of subjective figures are presented. They include: (a) apparent rotational movement as a result of shape invariance or rigidity; (b) apparent rotational movement with three-dimensional subjective figures not accompanied by a brightness gradient; and (c) apparent rotational movement by kinetic occlusion.     

Stick to the script: The effect of witnessing multiple actors on children’s imitation

What kinds of cues increase imitative fidelity in early childhood? The effects of multiple models and verbal framing were examined in preschool children (N = 259, 3–6-year-olds). Each participant was presented with one of eight possible combinations of type of modeling and verbal frame. The type of modeling involved: (i) a single model offering two demonstrations, (ii) two successive models each offering a single demonstration, (iii) two synchronous models each offering two demonstrations, or (iv) two synchronous models each offering a single demonstration. The verbal frame preceding the demonstrations emphasized either the instrumental outcome of the actions or their conventionality. Imitative fidelity was highest for the synchronous models (types iii and iv) and lowest for the single model (type i). Imitative fidelity was also higher for the convention-oriented than the outcome-oriented frame and higher for older than younger children. Children also provided more conventional explanations for their actions after viewing the synchronous models and after the convention-oriented framing. The results indicate that children’s imitative fidelity depends on the number of actors and the way the actions are framed.     

The quail, Coturnix coturnix, as a laboratory animal

The quail, Coturnix coturnix, is small, gentle, hardy, adaptable, easy to house, and economical to maintain. Wetherbee and Jacobs (1960) call it the “Drosophila of the avian laboratory,” and yet this charming bird is virtually unknown to the psychological laboratory. Our preliminary investigations show that the pecking operant is readily conditioned and that little or no deprivation is necessary to maintain behavior with food as a reinforcer. Visual and temporal discriminations were very quickly made. Our observations suggest that the social behavior of these birds might be a fruitful area for psychological study. On the basis of our somewhat limited observations, we believe that C. coturnix should prove a useful experimental animal for comparative studies, for basic research in learning, motivation, and perhaps social behavior, and for teaching the analysis of behavior in demonstrations and laboratory courses.     

How chimpanzees (<Emphasis Type="Italic">Pan troglodytes</Emphasis>) perform in a modified emotional Stroop task

The emotional Stroop task is an experimental paradigm developed to study the relationship between emotion and cognition. Human participants required to identify the color of words typically respond more slowly to negative than to neutral words (emotional Stroop effect). Here we investigated whether chimpanzees (Pan troglodytes) would show a comparable effect. Using a touch screen, eight chimpanzees were trained to choose between two simultaneously presented stimuli based on color (two identical images with differently colored frames). In Experiment 1, the images within the color frames were shapes that were either of the same color as the surrounding frame or of the alternative color. Subjects made fewer errors and responded faster when shapes were of the same color as the frame surrounding them than when they were not, evidencing that embedded images affected target selection. Experiment 2, a modified version of the emotional Stroop task, presented subjects with four different categories of novel images: three categories of pictures of humans (veterinarian, caretaker, and stranger), and control stimuli showing a white square. Because visits by the veterinarian that include anaesthetization can be stressful for subjects, we expected impaired performance in trials presenting images of the veterinarian. For the first session, we found correct responses to be indeed slower in trials of this category. This effect was more pronounced for subjects whose last anaesthetization experience was more recent, indicating that emotional valence caused the slowdown. We propose our modified emotional Stroop task as a simple method to explore which emotional stimuli affect cognitive performance in nonhuman primates.     

Language is not necessary for color categories

The origin of color categories is under debate. Some researchers argue that color categories are linguistically constructed, while others claim they have a pre‐linguistic, and possibly even innate, basis. Although there is some evidence that 4–6‐month‐old infants respond categorically to color, these empirical results have been challenged in recent years. First, it has been claimed that previous demonstrations of color categories in infants may reflect color preferences instead. Second, and more seriously, other labs have reported failing to replicate the basic findings at all. In the current study we used eye‐tracking to test 8‐month‐old infants’ categorical perception of a previously attested color boundary (green–blue) and an additional color boundary (blue–purple). Our results show that infants are faster and more accurate at fixating targets when they come from a different color category than when from the same category (even though the chromatic separation sizes were equated). This is the case for both blue–green and blue–purple. Our findings provide independent evidence for the existence of color categories in pre‐linguistic infants, and suggest that categorical perception of color can occur without color language.     

Context in verbal short-term memory

We tested the hypothesis that stimulus-related contextual information that is incidental to task demands-an episodic code-is automatically, obligatorily encoded and stored as a part of short-term memory (STM) representations. Four experiments employed a running span task to investigate the effects of manipulating two types of contextual information: stimulus grouping and color. Three experiments established that grouping context effects are sensitive neither to volitional control nor to task difficulty and that they generalize across testing procedures (yes/no recognition and immediate serial recall). A fourth experiment demonstrated an effect of manipulating the congruity of the color of stimuli between study and test. These demonstrations of the robustness and generality of context effects in STM are consistent with the predictions of the episodic coding model of STM.     

The effectiveness of electric shock and foul odor as unconditioned stimuli in classical aversive conditioning

In a partial replication of an earlier study, eighty undergraduate volunteers were assigned to the eight cells of a three between- and two within-group experimental design. One factor was the nature of the UCS—faradic shock or a carefully-timed blast of pyridine vapor; the second factor was the UCS contingency—the UCS being contingent upon the CS or randomly interspersed; the third factor was the nature of the CS—all CSs were compounds of colored, flavored liquids, with the discriminable dimension being either color or taste. The two within-subjects factors were the successive presentation of either the CS+ of the CS? over trials in a standard classical conditioning format. The outcome measures were sip-size, order of preference, and semantic differential ratings. It was found that the foul odor UCS resulted in no aversive conditioning with either color or taste cues. Where shock was the UCS, color, but not taste, became aversive. While lending no direct support to cue-appropriateness concepts, the results reveal the complexity of cue utilization in human aversive conditioning.     

Egg White or Sun-Kissed: A Cross-Cultural Exploration of Skin Color and Women’s Leisure Behavior

The present study explores how culture-based meanings and values toward skin color, which are associated with women’s body image ideals and gender-role expectations, profoundly influence women’s leisure behaviors. Using in-depth interviews with East Asian, Asian American, and Euro-American women (n?=?43), results revealed how leisure behaviors are tied to cultural perceptions of skin color. People from different cultural backgrounds construct meanings and values pertaining to skin color, including beauty-related standards, social class, gender roles, and lifestyles. Culture-based values, such as the preference for tanned skin among Euro-Americans and for lighter skin among East Asians, affect a wide range of daily behaviors. These behaviors include conscious as well as subtle daily decision-making regarding sun-seeking, sun-avoidance, and sun-protection behaviors; indoor versus outdoor leisure participation; and appearance modifications. The study’s results add knowledge to how perceptions and attitudes toward skin color and appearance manifest in women's daily behavior in general and leisure behavior in particular. In addition, the current study shows how individual behaviors reflect cultural meanings and values toward body image, specifically skin color, by emphasizing the links between cultural values and women’s day-to-day lives.     

Consumer preferences for color combinations: An empirical analysis of similarity-based color relationships

In this paper, we examine aesthetic color combinations in a realistic product self-design task using the NIKEiD online configurator. We develop a similarity-based model of color relationships and empirically model the choice likelihoods of color pairs as a function of the distances between colors in the CIELAB color space. Our empirical analysis reveals three key findings. First, people de-emphasize lightness and focus on hue and saturation. Second, given this shift in emphasis, people generally like to combine colors that are relatively close or exactly match, with the exception that some people highlight one signature product component by using contrastive color. This result is more consistent with the visual coherence perspective than the optimal arousal perspective on aesthetic preference. Third, a small palette principle is supported such that the total number of colors used in the average design was smaller than would be expected under statistical independence.     

Personality predicts innovation and social learning in children: Implications for cultural evolution

Innovation and social learning are the pillars of cultural evolution, allowing cultural behaviours to cumulatively advance over generations. Yet, little is known about individual differences in the use of social and asocial information. We examined whether personality influenced 7-11-year-old children's (N = 282) propensity to elect to observe others first or independently generate solutions to novel problems. Conscientiousness was associated with electing for no demonstrations, while agreeableness was associated with opting for demonstrations. For children receiving demonstrations, openness to experience consistently predicted deviation from observed methods. Children who opted for no demonstrations were also more likely than those opting for demonstrations to exhibit tool manufacture on an innovation challenge and displayed higher creativity, as measured by an alternate uses task. These results highlight how new cultural traditions emerge, establish and advance by identifying which individuals generate new cultural variants in populations and which are influential in the diffusion of these variants, and help reduce the apparent tension within the ‘ratchet’ of cumulative culture.     

Escalation and De-escalation of Commitment in Response to Sunk Costs: The Role of Budgeting in Mental Accounting

Research has traditionally assumed that people increase investment (or "escalate commitment") in response to previous investments (sunk costs). This paper presents several demonstrations which show that people will incorrectly de-escalate investment in response to sunk costs. I propose that people set mental budgets to control their resource expenditures: they set a budget for a class of expenses and track their investments against their budget. A lab study with real monetary incentives shows support for de-escalation and supports a specific rule for how people set budgets - based on the breakeven of total costs and total benefits. The budgeting process suggests that people are only likely to escalate commitment when they fail to set a budget or when expenses are difficult to track. The later part of the paper organizes the previous literature on escalation around these processes and provides additional experiments to illustrate each point. For example, I argue that previous demonstrations that have shown errors of escalation exclusively involve "incidental" investments that are difficult to track. A study in the current paper shows that people are more willing to invest time than money to salvage a monetary sunk cost and more willing to invest money than time to salvage a sunk cost of time, even when the time and money investments are of equal value. The paper concludes by discussing the rationality of escalation and de-escalation.     

The role of working memory in attentional capture

Much previous research has demonstrated that visual search is typically disrupted by the presence of a unique “singleton” distractor in the search display. Here we show that attentional capture by an irrelevant color singleton during shape search critically depends on availability of working memory to the search task: When working memory is loaded in a concurrent yet unrelated verbal short-term memory task, capture increases. These findings converge with previous demonstrations that increasing working memory load results in greater distractor interference in Stroop-like tasks (de Fockert, Rees, Frith, & Lavie, 2001; Lavie, Hirst, de Fockert, & Viding, 2004), which support the hypothesis that working memory provides goal-directed control of visual selective attention allowing to minimize interference by goal-irrelevant distractors.     

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.