Spontaneous representations of small numbers of objects by rhesus macaques: examinations of content and format

The project of comparative cognition benefits from common measures across species. We report here on five experiments using the violation of expectancy looking time measure with free-ranging rhesus macaques (Macaca mulatta), each designed to build on current knowledge concerning spontaneous representations of number. Each subject, tested in only one experimental condition, watched as eggplants were placed behind a screen one at a time, after which the screen was removed revealing an outcome that either matched or did not match the number placed there. Subjects looked longer at impossible than possible outcomes in 1+1=2 or 3, 1 small+1 small=1 big or 2 small, 2+1=2 or 3, and 2+1=3 or 4 conditions. They failed in 2+1+1=4 or 3 or 5 and in 1+1+1=2 or 3 conditions. This pattern of results closely matches that observed across several previous studies of human infants. The data allow us to test among four different proposals concerning the format and content of the mental representations underlying looking in these experiments. Object file representations are favored over: (i) low-level perceptual representations, (ii) representations of continuous variables such as volume or surface area, and (iii) analog magnitude representations of number. We conclude by considering exactly how the object tracking system revealed in these and other related experiments does and does not represent number, and how it might be one evolutionary precursor of the human specific system of number representations.     

Happiness, Mental Health, and Socio-Demographic Associations Among a National Cohort of Thai Adults

Research on happiness has been of interest in many parts of the world. Here we provide evidence from developing countries; this is the first analysis of happiness among a cohort of Thai distance learning adults residing throughout the country (n?=?60,569 in 2009). To measure happiness, we tested use of the short format Thai Mental Health Indicators (TMHI), correlating each domain with two direct measures of happiness and life satisfaction. Several TMHI domains correlated strongly with happiness. We found the mental state and the social support domains moderately or strongly correlated with happiness by either measure (correlation coefficients 0.24–0.56). The other two TMHI domains (mental capacity and mental quality) were not correlated with happiness. Analysis of socio-demographic attributes and happiness revealed little effect of age and sex but marital status (divorced or widowed), low household income, and no paid work all had strong adverse effects. Our findings provide Thai benchmarks for measuring happiness and associated socio-demographic attributes. We also provide evidence that the TMHI can measure happiness in the Thai population. Furthermore, the results among Thai cohort members can be monitored over time and could be useful for comparison with other Southeast Asian countries.     

Individual differences in multiple types of shifting attention

Many researchers consider costs in shifting attention and mental set to reflect a basic ability to use top-down goal information to guide action. Although switch costs have been used as measures of individuals' executive function, whether common abilities underlie task set switching across different types of shifting tasks has not been well studied. In 249 participants, we studied whether switch costs in a novel two-choice reaction time task were correlated across variations in two variables: thelocus of representation (stimuli were either perceptually available or stored in working memory [WM]) and which of two judgment tasks was performed. Switch costs were asymmetrical, in that it was easier to switch to the easier judgment, and were related to overall and relative processing speed: Switch costs were higher when the task was more difficult. These factors should be accounted for when one is measuring individual differences in switch costs. After controlling for these effects, we found evidence for a common ability underlying switch costs that involved both task set preparation and response selection; however, residual shift costs, which involve only response selection, were uncorrelated across tasks. Correlations among switch costs were substantially higher within task type (e.g., correlations of WM shifting tasks with other WM shifting tasks and of perceptual tasks with perceptual ones), suggesting that there are also processes unique to switching within WM and switching among visible stimuli.     

The Role of Gesture in Supporting Mental Representations: The Case of Mental Abacus Arithmetic

People frequently gesture when problem‐solving, particularly on tasks that require spatial transformation. Gesture often facilitates task performance by interacting with internal mental representations, but how this process works is not well understood. We investigated this question by exploring the case of mental abacus (MA), a technique in which users not only imagine moving beads on an abacus to compute sums, but also produce movements in gestures that accompany the calculations. Because the content of MA is transparent and readily manipulated, the task offers a unique window onto how gestures interface with mental representations. We find that the size and number of MA gestures reflect the length and difficulty of math problems. Also, by selectively interfering with aspects of gesture, we find that participants perform significantly worse on MA under motor interference, but that perceptual feedback is not critical for success on the task. We conclude that premotor processes involved in the planning of gestures are critical to mental representation in MA.     

Representations in mental imagery and working memory: Evidence from different types of visual masks

Although few studies have systematically investigated the relationship between visual mental imagery and visual working memory, work on the effects of passive visual interference has generally demonstrated a dissociation between the two functions. In four experiments, we investigated a possible commonality between the two functions: We asked whether both rely on depictive representations. Participants judged the visual properties of letters using visual mental images or pictures of unfamiliar letters stored in short-term memory. Participants performed both tasks with two different types of interference: sequences of unstructured visual masks (consisting of randomly changing white and black dots) or sequences of structured visual masks (consisting of fragments of letters). The structured visual noise contained elements of depictive representations (i.e., shape fragments arrayed in space), and hence should interfere with stored depictive representations; the unstructured visual noise did not contain such elements, and thus should not interfere as much with such stored representations. Participants did in fact make more errors in both tasks with sequences of structured visual masks. Various controls converged in demonstrating that in both tasks participants used representations that depicted the shapes of the letters. These findings not only constrain theories of visual mental imagery and visual working memory, but also have direct implications for why some studies have failed to find that dynamic visual noise interferes with visual working memory.     

Representations and Cognitive Explanations: Assessing the Dynamicist's Challenge in Cognitive Science

Advocates of dynamical systems theory (DST) sometimes employ revolutionary rhetoric. In an attempt to clarify how DST models differ from others in cognitive science, I focus on two issues raised by DST: the role for representations in mental models and the conception of explanation invoked. Two features of representations are their role in standing-in for features external to the system and their format. DST advocates sometimes claim to have repudiated the need for stand-ins in DST models, but I argue that they are mistaken. Nonetheless, DST does offer new ideas as to the format of representations employed in cognitive systems. With respect to explanation, I argue that some DST models are better seen as conforming to the covering-law conception of explanation than to the mechanistic conception of explanation implicit in most cognitive science research. But even here, I argue, DST models are a valuable complement to more mechanistic cognitive explanations.     

Time in the mind: using space to think about time

How do we construct abstract ideas like justice, mathematics, or time-travel? In this paper we investigate whether mental representations that result from physical experience underlie people's more abstract mental representations, using the domains of space and time as a testbed. People often talk about time using spatial language (e.g., a long vacation, a short concert). Do people also think about time using spatial representations, even when they are not using language? Results of six psychophysical experiments revealed that people are unable to ignore irrelevant spatial information when making judgments about duration, but not the converse. This pattern, which is predicted by the asymmetry between space and time in linguistic metaphors, was demonstrated here in tasks that do not involve any linguistic stimuli or responses. These findings provide evidence that the metaphorical relationship between space and time observed in language also exists in our more basic representations of distance and duration. Results suggest that our mental representations of things we can never see or touch may be built, in part, out of representations of physical experiences in perception and motor action.     

Imagining the future: degraded representations of future rewards and events in schizophrenia

Over the course of life, most people work toward temporally distant rewards such as university degrees or work-related promotions. In contrast, many people with schizophrenia show deficits in behavior oriented toward long-term rewards, although they function adequately when rewards are more immediately present. Moreover, when asked about possible future events, individuals with schizophrenia show foreshortened future time perspectives relative to healthy individuals. Here, we take the view that these deficits are related and can be explained by cognitive deficits. We compared the performance of participants with schizophrenia (n = 39) and healthy participants (n = 25) on tasks measuring reward discounting and future event representations. Consistent with previous research, we found that relative to healthy participants, those with schizophrenia discounted the value of future rewards more steeply. Furthermore, when asked about future events, their responses were biased toward events in the near future, relative to healthy participants' responses. Although discounting and future representations were unrelated in healthy participants, we found significant correlations across the tasks among participants with schizophrenia, as well as correlations with cognitive variables and symptoms. Further analysis showed that statistically controlling working memory eliminated group differences in task performance. Together these results suggest that the motivational deficits characteristic of schizophrenia relate to cognitive deficits affecting the ability to represent and/or evaluate distant outcomes, a finding with important implications for promoting recovery from schizophrenia.     

Are people with high and low mental rotation abilities differently susceptible to the alignment effect?

We investigated whether the alignment effect (Levine et al, 1982 Journal of Experimental Psychology: General 111 157-175) is influenced by mental rotation abilities. In two experiments, groups of undergraduate students with high and low performance in mental rotation tasks were required to study either schematic (experiment 1) or more complex (experiment 2) maps, and to perform a number of pointing tasks adopting a perspective which could be aligned, misaligned (45 degrees, 135 degrees), or counteraligned (180 degrees) with the perspective assumed during learning. Cognitive styles in spatial representation have also been considered. Results of experiment 1 show that people with low performance in mental rotation tasks prefer to adopt a representation of space focused more on landmarks. Their performance in the pointing tasks depends on the alignment conditions, with more errors in the counteraligned condition followed by the two misaligned and aligned ones. In contrast to this, high-ability mental rotators prefer survey and route spatial representations and are affected only by the aligned and non-aligned conditions. In the second experiment, practice was studied as a function of mental rotation and alignment. The group high in mental rotation ability was found to be free from the alignment effect in the pointing tasks performed after the final of four learning phases.     

Vividness of positive mental imagery predicts positive emotional response to visually presented Project Soothe pictures

Lang's bioinformational theory of mental imagery proposes that mental imagery and external stimuli engage emotional information-processing systems in similar ways. However, the positive and negative systems are thought to be distinct, so this similarity is likely to show a valence-specific effect. Therefore, we hypothesized that an individual's ability to construct vivid positive, but not negative, mental imagery would predict positive emotional responding to positive visual stimuli, independently of depressive symptoms. Our stimuli were pictures collected through Project Soothe for possible use in psychotherapy ( www.projectsoothe.com ); as these pictures were intended to induce soothing emotion, we hypothesized that theoretically linked variables Self-compassion and Self-criticism would also predict positive responding to the stimuli. A total of 214 participants completed an online study including validated questionnaire measures, mental imagery tasks, and a picture-rating exercise. Only Positive Imagery Vividness and Self-compassion were significant predictors of positive responding to the soothing pictures, even controlling for depressive symptoms, and Negative and General Imagery Vividness. These findings support Lang's theory and provide evidence for individual differences in a positive processing tendency shared across mental imagery-based and perceptual representations. As this relationship is distinct from depressive symptoms, future imagery-based psychotherapies might aim to influence this positive processing tendency.     

Orientation dependent mental representations following real-world navigation

The purpose of this study was to examine whether the mental representations acquired from real-world navigation are encoded in a single, specific orientation. Previous research has revealed an inconsistent pattern of results. In the present study, participants explored a university campus. In two reaction-time tasks, spatial judgments were then made relative to four imagined headings within the explored environment. The main result was that one of the headings was encoded in a distinct manner: When making left-right judgments performance on this heading was generally superior by comparison with the other orientations, and when making front-back judgments the same heading was the only one in which an advantage of front over back responses was observed. The finding that the headings were not encoded equally indicates that real-world navigation can lead to orientation specific representations.     

Mental representation of symbols as revealed by vocabulary errors in two bonobos (<Emphasis Type="Italic">Pan paniscus</Emphasis>)

Error analysis has been used in humans to detect implicit representations and categories in language use. The present study utilizes the same technique to report on mental representations and categories in symbol use from two bonobos (Pan paniscus). These bonobos have been shown in published reports to comprehend English at the level of a two-and-a-half year old child and to use a keyboard with over 200 visuographic symbols (lexigrams). In this study, vocabulary test errors from over 10 years of data revealed auditory, visual, and spatio-temporal generalizations (errors were more likely items that looked like sounded like, or were frequently associated with the sample item in space or in time), as well as hierarchical and conceptual categorizations. These error data, like those of humans, are a result of spontaneous responding rather than specific training and do not solely depend upon the sample mode (e.g. auditory similarity errors are not universally more frequent with an English sample, nor were visual similarity errors universally more frequent with a photograph sample). However, unlike humans, these bonobos do not make errors based on syntactical confusions (e.g. confusing semantically unrelated nouns), suggesting that they may not separate syntactical and semantic information. These data suggest that apes spontaneously create a complex, hierarchical, web of representations when exposed to a symbol system. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

A qualitative evaluation of a mental health literacy intervention for parents delivered through community sport clubs

Intervention studies have rarely targeted parent mental health literacy despite its importance for adolescent mental health. This qualitative study evaluated the experiences of parents (n = 352) who participated in the Ahead of the Game mental health literacy workshop delivered through community sport clubs. Moreover, the study aimed to investigate the relevance, retention and use of intervention content by parents, assess the acceptability and feasibility of delivering mental health education through community sport clubs, and identify strategies for increased engagement. In total, 17 parents (13 mothers, four fathers) participated in semi-structured interviews up to one month after the workshop. Reflexive thematic analysis revealed that parents perceived mental health education as important and valuable, and believed the community sport club was an appropriate setting to discuss adolescent mental health. Parents reported increased awareness and knowledge of mental health disorders and help-seeking options, and increased confidence and preparedness to communicate and assist someone experiencing a mental health issue. The workshop stimulated conversation about mental health between parents and their children, and between parents within and outside the sport club community. Parents used information and resources provided in the workshop to help those in their networks and reflected back on the workshop when noticing changes in their adolescent’s behavior. Potential additions to the workshop (as suggested by parents) included increased discussion among parents as well as opportunities for further information sessions or tailored online material. Future research might look to engage more fathers, actively encourage parents to aid in the recruitment of others, and investigate long-term adolescent mental health outcomes.     

The effects of feedback format on dynamic decision making

The tendency for people to perform poorly on dynamic decision-making tasks has been attributed to their inability to form adequate mental models of dynamic systems (Sterman, 1994). An alternative explanation is that the tabular feedback formats used in previous studies do not facilitate mental representations of the dynamic task and lead to processing overload. Drawing on research in the human factors area, this study examined the impact of graphical versus tabular feedback formats on performance, response times, and learning on a dynamic inventory control task under differing levels of complexity. The graphical feedback group performed better but the tabular group showed stronger evidence of learning. The two groups did not differ in response times. Records of decision rationales showed that participants were aware of complexity factors but were unable to cope with them effectively under either feedback format. The proximity compatibility principle ( Wickens & Carswell, 1995) from human factors, which argues that feedback must be matched to the processing requirements of the task, provides a useful theoretical framework for the design and testing of feedback formats for organizational tasks and criteria.     

Visual mental rotation of possible and impossible objects

Participants were tested on two visual mental rotation tasks using three-dimensional "possible" and "impossible" shapes. Both types of stimuli can be easily encoded by their parts and how they are spatially organized. However, while possible shapes can also be easily encoded as a global image, it is more difficult to encode impossible shapes in such a way. Participants visually rotated both types of stimuli at comparable rates, reflecting that local representations were used in the process of visual mental rotation.     

Cognitive complexity of social images revealed by Jewish Israeli adolescents relating to drawings of Jews and Arabs

The present study examined age‐related differences among Israeli youth regarding the complexity of their mental images of Jews and Arabs, two groups that are adversaries in the Middle East conflict. The participants, 494 Jewish children and adolescents ranging from 8–16 years old each, drew two human figures, one Jewish and one Arab, and then attributed a forename and a profession to each drawn image. Four complexity variables were scored as follows: image complexity (number of items included in the figure), embellishments (number of items added to the drawing and in the space around the figure), image name, and image profession. Overall, participants depicted members of their in‐group as more complex. However, early adolescence was found to be a critical age at which differences emerged. The findings suggest that introducing complexity to social representations in early adolescence may facilitate prevention of negative associations related to outgroups and enhance intervention to reduce stereotypes, prejudice, and racism.