Effects of changes in size, speed and distance on the perception of curved 3D trajectories

PubMed Central

Zhang, Junjun; Braunstein, Myron L.; Andersen, George J.

2012-01-01

Previous research on the perception of 3D object motion has considered time to collision, time to passage, collision detection and judgments of speed and direction of motion, but has not directly studied the perception of the overall shape of the motion path. We examined the perception of the magnitude of curvature and sign of curvature of the motion path for objects moving at eye level in a horizontal plane parallel to the line of sight. We considered two sources of information for the perception of motion trajectories: changes in angular size and changes in angular speed. Three experiments examined judgments of relative curvature for objects moving at different distances. At the closest distance studied, accuracy was high with size information alone but near chance with speed information alone. At the greatest distance, accuracy with size information alone decreased sharply but accuracy for displays with both size and speed information remained high. We found similar results in two experiments with judgments of sign of curvature. Accuracy was higher for displays with both size and speed information than with size information alone, even when the speed information was based on parallel projections and was not informative about sign of curvature. For both magnitude of curvature and sign of curvature judgments, information indicating that the trajectory was curved increased accuracy, even when this information was not directly relevant to the required judgment. PMID:23007204

Stimulus size and eccentricity in visually induced perception of horizontally translational self-motion.

PubMed

Nakamura, S; Shimojo, S

1998-10-01

The effects of the size and eccentricity of the visual stimulus upon visually induced perception of self-motion (vection) were examined with various sizes of central and peripheral visual stimulation. Analysis indicated the strength of vection increased linearly with the size of the area in which the moving pattern was presented, but there was no difference in vection strength between central and peripheral stimuli when stimulus sizes were the same. Thus, the effect of stimulus size is homogeneous across eccentricities in the visual field.

Testing effects in visual short-term memory: The case of an object's size.

PubMed

Makovski, Tal

2018-05-29

In many daily activities, we need to form and retain temporary representations of an object's size. Typically, such visual short-term memory (VSTM) representations follow perception and are considered reliable. Here, participants were asked to hold in mind a single simple object for a short duration and to reproduce its size by adjusting the length and width of a test probe. Experiment 1 revealed two powerful findings: First, similar to a recently reported perceptual illusion, participants greatly overestimated the size of open objects - ones with missing boundaries - relative to the same-size fully closed objects. This finding confirms that object boundaries are critical for size perception and memory. Second, and in contrast to perception, even the size of the closed objects was largely overestimated. Both inflation effects were substantial and were replicated and extended in Experiments 2-5. Experiments 6-8 used a different testing procedure to examine whether the overestimation effects are due to inflation of size in VSTM representations or to biases introduced during the reproduction phase. These data showed that while the overestimation of the open objects was repeated, the overestimation of the closed objects was not. Taken together, these findings suggest that similar to perception, only the size representation of open objects is inflated in VSTM. Importantly, they demonstrate the considerable impact of the testing procedure on VSTM tasks and further question the use of reproduction procedures for measuring VSTM.

The Impact of Nutrition and Health Claims on Consumer Perceptions and Portion Size Selection: Results from a Nationally Representative Survey.

PubMed

Benson, Tony; Lavelle, Fiona; Bucher, Tamara; McCloat, Amanda; Mooney, Elaine; Egan, Bernadette; Collins, Clare E; Dean, Moira

2018-05-22

Nutrition and health claims on foods can help consumers make healthier food choices. However, claims may have a 'halo' effect, influencing consumer perceptions of foods and increasing consumption. Evidence for these effects are typically demonstrated in experiments with small samples, limiting generalisability. The current study aimed to overcome this limitation through the use of a nationally representative survey. In a cross-sectional survey of 1039 adults across the island of Ireland, respondents were presented with three different claims (nutrition claim = "Low in fat"; health claim = "With plant sterols. Proven to lower cholesterol"; satiety claim = "Fuller for longer") on four different foods (cereal, soup, lasagne, and yoghurt). Participants answered questions on perceived healthiness, tastiness, and fillingness of the products with different claims and also selected a portion size they would consume. Claims influenced fillingness perceptions of some of the foods. However, there was little influence of claims on tastiness or healthiness perceptions or the portion size selected. Psychological factors such as consumers' familiarity with foods carrying claims and belief in the claims were the most consistent predictors of perceptions and portion size selection. Future research should identify additional consumer factors that may moderate the relationships between claims, perceptions, and consumption.

The Impact of Nutrition and Health Claims on Consumer Perceptions and Portion Size Selection: Results from a Nationally Representative Survey

PubMed Central

Benson, Tony; Lavelle, Fiona; McCloat, Amanda; Mooney, Elaine; Egan, Bernadette; Collins, Clare E.; Dean, Moira

2018-01-01

Nutrition and health claims on foods can help consumers make healthier food choices. However, claims may have a ‘halo’ effect, influencing consumer perceptions of foods and increasing consumption. Evidence for these effects are typically demonstrated in experiments with small samples, limiting generalisability. The current study aimed to overcome this limitation through the use of a nationally representative survey. In a cross-sectional survey of 1039 adults across the island of Ireland, respondents were presented with three different claims (nutrition claim = “Low in fat”; health claim = “With plant sterols. Proven to lower cholesterol”; satiety claim = “Fuller for longer”) on four different foods (cereal, soup, lasagne, and yoghurt). Participants answered questions on perceived healthiness, tastiness, and fillingness of the products with different claims and also selected a portion size they would consume. Claims influenced fillingness perceptions of some of the foods. However, there was little influence of claims on tastiness or healthiness perceptions or the portion size selected. Psychological factors such as consumers’ familiarity with foods carrying claims and belief in the claims were the most consistent predictors of perceptions and portion size selection. Future research should identify additional consumer factors that may moderate the relationships between claims, perceptions, and consumption. PMID:29789472

Testing the generality of the zoom-lens model: Evidence for visual-pathway specific effects of attended-region size on perception.

PubMed

Goodhew, Stephanie C; Lawrence, Rebecca K; Edwards, Mark

2017-05-01

There are volumes of information available to process in visual scenes. Visual spatial attention is a critically important selection mechanism that prevents these volumes from overwhelming our visual system's limited-capacity processing resources. We were interested in understanding the effect of the size of the attended area on visual perception. The prevailing model of attended-region size across cognition, perception, and neuroscience is the zoom-lens model. This model stipulates that the magnitude of perceptual processing enhancement is inversely related to the size of the attended region, such that a narrow attended-region facilitates greater perceptual enhancement than a wider region. Yet visual processing is subserved by two major visual pathways (magnocellular and parvocellular) that operate with a degree of independence in early visual processing and encode contrasting visual information. Historically, testing of the zoom-lens has used measures of spatial acuity ideally suited to parvocellular processing. This, therefore, raises questions about the generality of the zoom-lens model to different aspects of visual perception. We found that while a narrow attended-region facilitated spatial acuity and the perception of high spatial frequency targets, it had no impact on either temporal acuity or the perception of low spatial frequency targets. This pattern also held up when targets were not presented centrally. This supports the notion that visual attended-region size has dissociable effects on magnocellular versus parvocellular mediated visual processing.

Perceptions as the crucial link? The mediating role of neighborhood perceptions in the relationship between the neighborhood context and neighborhood cohesion.

PubMed

Laméris, Joran; Hipp, John R; Tolsma, Jochem

2018-05-01

This study examines the effects of neighborhood racial in-group size, economic deprivation and the prevalence of crime on neighborhood cohesion among U.S. whites. We explore to what extent residents' perceptions of their neighborhood mediate these macro-micro relationships. We use a recent individual-level data set, the American Social Fabric Study (2012/2013), enriched with contextual-level data from the U.S. Census Bureau (2010) and employ multi-level structural equation models. We show that the racial in-group size is positively related to neighborhood cohesion and that neighborhood cohesion is lower in communities with a high crime rate. Individuals' perceptions of the racial in-group size partly mediate the relationship between the objective racial in-group size and neighborhood cohesion. Residents' perceptions of unsafety from crime also appear to be a mediating factor, not only for the objective crime rate but also for the objective racial in-group size. This is in line with our idea that racial stereotypes link racial minorities to crime whereby neighborhoods with a large non-white population are perceived to be more unsafe. Residents of the same neighborhood differ in how they perceive the degree of economic decay of the neighborhood and this causes them to evaluate neighborhood cohesion differently, however perceptions of neighborhood economic decay do not explain the link between the objective neighborhood context and neighborhood cohesion. Copyright © 2018. Published by Elsevier Inc.

Perceptions relating to body size, weight loss and weight-loss interventions in black South African women: a qualitative study.

PubMed

Draper, Catherine E; Davidowitz, Kesiah J; Goedecke, Julia H

2016-02-01

A higher tolerance for a larger body size has been associated with obesity in black South African (SA) women. The aim of the present study was to explore perceptions regarding body size and weight loss in a sample of black women from a low-income community in Cape Town, SA. Qualitative pilot study including five focus groups. Data were analysed using thematic analysis. Khayelitsha, Cape Town, SA. Twenty-one black SA women. The majority of participants had positive perceptions of overweight/obesity, which were influenced by community and cultural perceptions, but some inconsistencies were observed as overweight/obesity was also associated with ill health. Participants identified many benefits to weight loss, but due to the association with sickness, they were concerned about being stigmatised in their community. Although participants had knowledge about healthy eating, the main barrier to eating healthily included the perceived higher cost of healthier food and food insecurity. All participants saw exercise as a strategy to lose weight and improve health, and were interested in participating in a community-based exercise intervention, but negative community perceptions and conflicting views regarding who should lead the intervention were identified as barriers. These findings highlight the complexities surrounding participants' perceptions regarding body size, weight loss and weight-loss interventions, and emphasise low socio-economic status as a barrier to change. The study also highlights the strong influence of cultural ideals and community perceptions on personal perceptions. These findings underscore the necessity for culturally appropriate weight-loss interventions in low-income, transitioning communities.

Illusions of having small or large invisible bodies influence visual perception of object size

PubMed Central

van der Hoort, Björn; Ehrsson, H. Henrik

2016-01-01

The size of our body influences the perceived size of the world so that objects appear larger to children than to adults. The mechanisms underlying this effect remain unclear. It has been difficult to dissociate visual rescaling of the external environment based on an individual’s visible body from visual rescaling based on a central multisensory body representation. To differentiate these potential causal mechanisms, we manipulated body representation without a visible body by taking advantage of recent developments in body representation research. Participants experienced the illusion of having a small or large invisible body while object-size perception was tested. Our findings show that the perceived size of test-objects was determined by the size of the invisible body (inverse relation), and by the strength of the invisible body illusion. These findings demonstrate how central body representation directly influences visual size perception, without the need for a visible body, by rescaling the spatial representation of the environment. PMID:27708344

Problems in depth perception : perceived size and distance of familiar objects.

DOT National Transportation Integrated Search

1966-06-01

Judgments of the distance of familiar objects, especially other aircraft, are critical aspects of flight safety. In this study, the perception of distance as a function of the retinal size of a familiar object was investigated by simulating a station...

Dissatisfaction with own body makes patients with eating disorders more sensitive to pain

PubMed Central

Yamamotova, Anna; Bulant, Josef; Bocek, Vaclav; Papezova, Hana

2017-01-01

Body image represents a multidimensional concept including body image evaluation and perception of body appearance. Disturbances of body image perception are considered to be one of the central aspects of anorexia nervosa and bulimia nervosa. There is growing evidence that body image distortion can be associated with changes in pain perception. The aim of our study was to examine the associations between body image perception, body dissatisfaction, and nociception in women with eating disorders and age-matched healthy control women. We measured body dissatisfaction and pain sensitivity in 61 patients with Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition diagnoses of eating disorders (31 anorexia nervosa and 30 bulimia nervosa) and in 30 healthy women. Thermal pain threshold latencies were evaluated using an analgesia meter and body image perception and body dissatisfaction were assessed using Anamorphic Micro software (digital pictures of their own body distorted into larger-body and thinner-body images). Patients with eating disorders overestimated their body size in comparison with healthy controls, but the two groups did not differ in body dissatisfaction. In anorexia and bulimia patient groups, body dissatisfaction (calculated in pixels as desired size/true image size) correlated with pain threshold latencies (r=0.55, p=0.001), while between body image perception (determined as estimation size/true image size) and pain threshold, no correlation was found. Thus, we demonstrated that in patients with eating disorders, pain perception is significantly associated with emotional contrary to sensory (visual) processing of one’s own body image. The more the patients desired to be thin, the more pain-sensitive they were. Our findings based on some shared mechanisms of body dissatisfaction and pain perception support the significance of negative emotions specific for eating disorders and contribute to better understanding of the psychosomatic characteristics of this spectrum of illnesses. PMID:28761371

Perspective Space as a Model for Distance and Size Perception.

PubMed

Erkelens, Casper J

2017-01-01

In the literature, perspective space has been introduced as a model of visual space. Perspective space is grounded on the perspective nature of visual space during both binocular and monocular vision. A single parameter, that is, the distance of the vanishing point, transforms the geometry of physical space into that of perspective space. The perspective-space model predicts perceived angles, distances, and sizes. The model is compared with other models for distance and size perception. Perspective space predicts that perceived distance and size as a function of physical distance are described by hyperbolic functions. Alternatively, power functions have been widely used to describe perceived distance and size. Comparison of power and hyperbolic functions shows that both functions are equivalent within the range of distances that have been judged in experiments. Two models describing perceived distance on the ground plane appear to be equivalent with the perspective-space model too. The conclusion is that perspective space unifies a number of models of distance and size perception.

Perspective Space as a Model for Distance and Size Perception

PubMed Central

2017-01-01

In the literature, perspective space has been introduced as a model of visual space. Perspective space is grounded on the perspective nature of visual space during both binocular and monocular vision. A single parameter, that is, the distance of the vanishing point, transforms the geometry of physical space into that of perspective space. The perspective-space model predicts perceived angles, distances, and sizes. The model is compared with other models for distance and size perception. Perspective space predicts that perceived distance and size as a function of physical distance are described by hyperbolic functions. Alternatively, power functions have been widely used to describe perceived distance and size. Comparison of power and hyperbolic functions shows that both functions are equivalent within the range of distances that have been judged in experiments. Two models describing perceived distance on the ground plane appear to be equivalent with the perspective-space model too. The conclusion is that perspective space unifies a number of models of distance and size perception. PMID:29225765

Corporate financial decision makers' perceptions of their company's safety performance, programs and personnel: Do company size and industry injury risk matter?

PubMed

DeArmond, Sarah; Huang, Yueng-Hsiang; Chen, Peter Y; Courtney, Theodore K

2010-01-01

Top-level managers make important decisions about safety-related issues, yet little research has been done involving these individuals. The current study explored corporate financial decisions makers' perceptions of their company's safety and their justifications for these perceptions. This study also explored whether their perceptions and justifications varied as a function of company size or industry injury risk. A total of 404 individuals who were the most senior managers responsible for making decisions about property and casualty risk at their companies participated in this study. The participants took part in a telephone survey. The results suggest that corporate financial decision makers have positive views of safety at their companies relative to safety at other companies within their industries. Further, many believe their company's safety is influenced by the attention/emphasis placed on safety and the selection and training of safety personnel. Participants' perceptions varied somewhat based on the size of their company and the level of injury risk in their industry. While definitive conclusions about corporate financial decision makers' perceptions of safety cannot be reached as a result of this single study, this work does lay groundwork for future research aimed at better understanding the perceptions top-level managers.

Effect of stimuli presentation method on perception of room size using only acoustic cues

NASA Astrophysics Data System (ADS)

Hunt, Jeffrey Barnabas

People listen to music and speech in a large variety of rooms and many room parameters, including the size of the room, can drastically affect how well the speech is understood or the music enjoyed. While multi-modal (typically hearing and sight) tests may be more realistic, in order to isolate what acoustic cues listeners use to determine the size of a room, a listening-only tests is conducted here. Nearly all of the studies to-date on the perception of room volume using acoustic cues have presented the stimuli only over headphones and these studies have reported that, in most cases, the perceived room volume is more highly correlated with the perceived reverberation (reverberance) than with actual room volume. While reverberance may be a salient acoustic cue used for the determination or room size, the actual sound field in a room is not accurately reproduced when presented over headphones and it is thought that some of the complexities of the sound field that relate to perception of geometric volume, specifically directional information of reflections, may be lost. It is possible that the importance of reverberance may be overemphasized when using only headphones to present stimuli so a comparison of room-size perception is proposed where the sound field (from modeled and recorded impulse responses) is presented both over headphones and also over a surround system using higher order ambisonics to more accurately produce directional sound information. Major results are that, in this study, no difference could be seen between the two presentation methods and that reverberation time is highly correlated to room-size perception while real room size is not.

Perceptions of Body Size in Mothers and Their Young Children in the Galapagos Islands.

PubMed

Waldrop, Julee B; Page, Rachel A; Bentley, Margaret E

2016-10-01

Introduction Little specific information has been published about the health of people who live in the Galapagos Islands. As part of determining the status of the nutrition transition that may be occurring in the islands mothers of young children in the Galapagos perceptions of their child's body size and therefore health status was evaluated along with actual body size. Methods This paper presents data collected as part of a pilot study that used a mixed methods approach to identify and describe health and nutrition issues for mother-child pairs on Isla Isabela in Galapagos, Ecuador. It includes participant anthropometric assessment and self-perception of body size using silhouettes for themselves and one of their children along with open-ended questions to elicit further understanding of body size perceptions. Twenty mothers of children greater than 6 months of age but less than 6 years of age were interviewed. Results The women preferred a smaller body size for themselves but a larger body size for their children. Findings of different body size combinations between mothers and children in the same household demonstrated that the island is undergoing or may be post the nutrition transition. Discussion This dual burden of body weights (especially overweight or obese mothers) in the same household with underweight, normal and overweight or obese children and the potential nutrition related chronic disease burden in the future will require more educational resources and innovative health services than are currently available for the people of the Galapagos.

Both vision-for-perception and vision-for-action follow Weber's law at small object sizes, but violate it at larger sizes.

PubMed

Bruno, Nicola; Uccelli, Stefano; Viviani, Eva; de'Sperati, Claudio

2016-10-01

According to a previous report, the visual coding of size does not obey Weber's law when aimed at guiding a grasp (Ganel et al., 2008a). This result has been interpreted as evidence for a fundamental difference between sensory processing in vision-for-perception, which needs to compress a wide range of physical objects to a restricted range of percepts, and vision-for-action when applied to the much narrower range of graspable and reachable objects. We compared finger aperture in a motor task (precision grip) and perceptual task (cross modal matching or "manual estimation" of the object's size). Crucially, we tested the whole range of graspable objects. We report that both grips and estimations clearly violate Weber's law with medium-to-large objects, but are essentially consistent with Weber's law with smaller objects. These results differ from previous characterizations of perception-action dissociations in the precision of representations of object size. Implications for current functional interpretations of the dorsal and ventral processing streams in the human visual system are discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Garment sizes in perception of body size.

PubMed

Fan, Jintu; Newton, Edward; Lau, Lilian; Liu, Fu

2003-06-01

This paper reports an experimental investigation of the effect of garment size on perceived body size. The perceived body sizes of three Chinese men (thin, medium, and obese build) wearing different sizes of white T-shirts were assessed using Thompson and Gray's 1995 Nine-figural Scale in 1 (thinnest) to 9 (obese) grade and a newly-proposed method. Within the limit of commercially available T-shirt sizes, for thin and medium persons, perceived body sizes are bigger when wearing T-shirts of larger sizes. For an obese person, however, wearing a large size T-shirt tends to make him look thinner. The study also showed that the newly proposed comparative method is more reliable in comparing body size perception but without measuring the magnitude of the change in body-size grade. The figural scale and the comparative method can be complementary.

Audiovisual Interval Size Estimation Is Associated with Early Musical Training.

PubMed

Abel, Mary Kathryn; Li, H Charles; Russo, Frank A; Schlaug, Gottfried; Loui, Psyche

2016-01-01

Although pitch is a fundamental attribute of auditory perception, substantial individual differences exist in our ability to perceive differences in pitch. Little is known about how these individual differences in the auditory modality might affect crossmodal processes such as audiovisual perception. In this study, we asked whether individual differences in pitch perception might affect audiovisual perception, as it relates to age of onset and number of years of musical training. Fifty-seven subjects made subjective ratings of interval size when given point-light displays of audio, visual, and audiovisual stimuli of sung intervals. Audiovisual stimuli were divided into congruent and incongruent (audiovisual-mismatched) stimuli. Participants' ratings correlated strongly with interval size in audio-only, visual-only, and audiovisual-congruent conditions. In the audiovisual-incongruent condition, ratings correlated more with audio than with visual stimuli, particularly for subjects who had better pitch perception abilities and higher nonverbal IQ scores. To further investigate the effects of age of onset and length of musical training, subjects were divided into musically trained and untrained groups. Results showed that among subjects with musical training, the degree to which participants' ratings correlated with auditory interval size during incongruent audiovisual perception was correlated with both nonverbal IQ and age of onset of musical training. After partialing out nonverbal IQ, pitch discrimination thresholds were no longer associated with incongruent audio scores, whereas age of onset of musical training remained associated with incongruent audio scores. These findings invite future research on the developmental effects of musical training, particularly those relating to the process of audiovisual perception.

Audiovisual Interval Size Estimation Is Associated with Early Musical Training

PubMed Central

Abel, Mary Kathryn; Li, H. Charles; Russo, Frank A.; Schlaug, Gottfried; Loui, Psyche

2016-01-01

Although pitch is a fundamental attribute of auditory perception, substantial individual differences exist in our ability to perceive differences in pitch. Little is known about how these individual differences in the auditory modality might affect crossmodal processes such as audiovisual perception. In this study, we asked whether individual differences in pitch perception might affect audiovisual perception, as it relates to age of onset and number of years of musical training. Fifty-seven subjects made subjective ratings of interval size when given point-light displays of audio, visual, and audiovisual stimuli of sung intervals. Audiovisual stimuli were divided into congruent and incongruent (audiovisual-mismatched) stimuli. Participants’ ratings correlated strongly with interval size in audio-only, visual-only, and audiovisual-congruent conditions. In the audiovisual-incongruent condition, ratings correlated more with audio than with visual stimuli, particularly for subjects who had better pitch perception abilities and higher nonverbal IQ scores. To further investigate the effects of age of onset and length of musical training, subjects were divided into musically trained and untrained groups. Results showed that among subjects with musical training, the degree to which participants’ ratings correlated with auditory interval size during incongruent audiovisual perception was correlated with both nonverbal IQ and age of onset of musical training. After partialing out nonverbal IQ, pitch discrimination thresholds were no longer associated with incongruent audio scores, whereas age of onset of musical training remained associated with incongruent audio scores. These findings invite future research on the developmental effects of musical training, particularly those relating to the process of audiovisual perception. PMID:27760134

The relationship between mother to child calories served and maternal perception of hunger.

PubMed

Stromberg, S E; Janicke, D M

2016-06-01

Research has examined self-serving portions in adults and children and has shown that larger portion size is related to more calories consumed. The present study examines factors that may influence the portion sizes a mother serves her child at a mealtime. The present observational study included a community-based sample of 29 mother-child dyads. Dyads attended a 1-h session in which they shared a meal together. A buffet of food was provided and the mother was asked to serve her child and herself. The amount of food served and consumed by the child was recorded. Main independent variables of interest included maternal body mass index (BMI), child BMI Z-score, and maternal perception of personal and child hunger. The primary dependent variable was the total calories the mother served her child. Regression models and a moderated mediation were used to examine the relation between variables. Calories served to the child was positively associated with calories consumed by the child. Maternal perception of her own hunger was related to her perception of her child's hunger. Furthermore, maternal perception of child hunger explained the relationship between maternal perception of personal hunger and total calories served to the child, although only for obese mothers. Mothers may be serving their children larger portion sizes based on their personal weight and their perception of their child's hunger. To help children obtain or maintain a healthy weight, obesity prevention and intervention programmes should help mothers serve more appropriate serving sizes to their children. © 2015 The British Dietetic Association Ltd.

Plunging into the pool of death: Imagining a dangerous outcome influences distance perception

PubMed Central

Stefanucci, Jeanine K.; Gagnon, Kyle T.; Tompkins, Christopher L.; Bullock, Kendall E.

2012-01-01

The current studies examined whether manipulating the imagined consequences of falling would influence the perception of height, distance, and size. In Experiment 1, height and size perception were measured when participants stood at a short height (.89 m) or a medium height (1.91 m) above either an empty pool or a pool filled with a bed of nails. Participants who viewed the bed of nails and imagined falling into it estimated both the height as taller and the size of the bed of nails as larger than participants who imagined falling into an empty pool. In a second experiment, participants overestimated the horizontal ground distance to and across the bed of nails after being told to imagine jumping over it. Overall, these experiments suggest that costs associated with imagined actions can influence the perception of both vertical and horizontal extents that are not inherently dangerous. PMID:22611659

Visual exposure to large and small portion sizes and perceptions of portion size normality: Three experimental studies.

PubMed

Robinson, Eric; Oldham, Melissa; Cuckson, Imogen; Brunstrom, Jeffrey M; Rogers, Peter J; Hardman, Charlotte A

2016-03-01

Portion sizes of many foods have increased in recent times. In three studies we examined the effect that repeated visual exposure to larger versus smaller food portion sizes has on perceptions of what constitutes a normal-sized food portion and measures of portion size selection. In studies 1 and 2 participants were visually exposed to images of large or small portions of spaghetti bolognese, before making evaluations about an image of an intermediate sized portion of the same food. In study 3 participants were exposed to images of large or small portions of a snack food before selecting a portion size of snack food to consume. Across the three studies, visual exposure to larger as opposed to smaller portion sizes resulted in participants considering a normal portion of food to be larger than a reference intermediate sized portion. In studies 1 and 2 visual exposure to larger portion sizes also increased the size of self-reported ideal meal size. In study 3 visual exposure to larger portion sizes of a snack food did not affect how much of that food participants subsequently served themselves and ate. Visual exposure to larger portion sizes may adjust visual perceptions of what constitutes a 'normal' sized portion. However, we did not find evidence that visual exposure to larger portions altered snack food intake. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Psychophysical Test for the Independence of Perception and Action

ERIC Educational Resources Information Center

Amazeen, Eric L.; DaSilva, Flavio

2005-01-01

Research has suggested that perception and action are independent (see M. A. Goodale & A. Haffenden, 1998). The authors used the Ebbinghaus illusion to test this hypothesis in 2 experiments. Verbal reports of perceived size were compared with maximum grip aperture during grasping (Experiment 1) and manual reports of perceived size (Experiment 2).…

Diabetes Awareness and Body Size Perceptions of Cree Schoolchildren

ERIC Educational Resources Information Center

Willows, Noreen D.; Marshall, Dru; Raine, Kim; Ridley, Denise C.

2009-01-01

Native American Indians and First Nations are predisposed to obesity and diabetes. A study was done to understand Cree schoolchildren's diabetes awareness and body size perceptions in two communities that had diabetes awareness-raising activities in the Province of Quebec, Canada. Children (N = 203) in grades 4-6 were classified into weight…

Impact of facial defect reconstruction on attractiveness and negative facial perception.

PubMed

Dey, Jacob K; Ishii, Masaru; Boahene, Kofi D O; Byrne, Patrick; Ishii, Lisa E

2015-06-01

Measure the impact of facial defect reconstruction on observer-graded attractiveness and negative facial perception. Prospective, randomized, controlled experiment. One hundred twenty casual observers viewed images of faces with defects of varying sizes and locations before and after reconstruction as well as normal comparison faces. Observers rated attractiveness, defect severity, and how disfiguring, bothersome, and important to repair they considered each face. Facial defects decreased attractiveness -2.26 (95% confidence interval [CI]: -2.45, -2.08) on a 10-point scale. Mixed effects linear regression showed this attractiveness penalty varied with defect size and location, with large and central defects generating the greatest penalty. Reconstructive surgery increased attractiveness 1.33 (95% CI: 1.18, 1.47), an improvement dependent upon size and location, restoring some defect categories to near normal ranges of attractiveness. Iterated principal factor analysis indicated the disfiguring, important to repair, bothersome, and severity variables were highly correlated and measured a common domain; thus, they were combined to create the disfigured, important to repair, bothersome, severity (DIBS) factor score, representing negative facial perception. The DIBS regression showed defect faces have a 1.5 standard deviation increase in negative perception (DIBS: 1.69, 95% CI: 1.61, 1.77) compared to normal faces, which decreased by a similar magnitude after surgery (DIBS: -1.44, 95% CI: -1.49, -1.38). These findings varied with defect size and location. Surgical reconstruction of facial defects increased attractiveness and decreased negative social facial perception, an impact that varied with defect size and location. These new social perception data add to the evidence base demonstrating the value of high-quality reconstructive surgery. NA. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

Mass is all that matters in the size-weight illusion.

PubMed

Plaisier, Myrthe A; Smeets, Jeroen B J

2012-01-01

An object in outer space is weightless due to the absence of gravity, but astronauts can still judge whether one object is heavier than another one by accelerating the object. How heavy an object feels depends on the exploration mode: an object is perceived as heavier when holding it against the pull of gravity than when accelerating it. At the same time, perceiving an object's size influences the percept: small objects feel heavier than large objects with the same mass (size-weight illusion). Does this effect depend on perception of the pull of gravity? To answer this question, objects were suspended from a long wire and participants were asked to push an object and rate its heaviness. This way the contribution of gravitational forces on the percept was minimised. Our results show that weight is not at all necessary for the illusion because the size-weight illusion occurred without perception of weight. The magnitude of the illusion was independent of whether inertial or gravitational forces were perceived. We conclude that the size-weight illusion does not depend on prior knowledge about weights of object, but instead on a more general knowledge about the mass of objects, independent of the contribution of gravity. Consequently, the size-weight illusion will have the same magnitude on Earth as it should have on the Moon or even under conditions of weightlessness.

Dental health between self-perception, clinical evaluation and body image dissatisfaction - a cross-sectional study in mixed dentition pre-pubertal children.

PubMed

Banu, Ancuta; Șerban, Costela; Pricop, Marius; Urechescu, Horatiu; Vlaicu, Brigitha

2018-05-03

Self-perception of oral health status is a multidimensional construct that includes psychological, psychosocial and functional aspects of oral health. Contemporary concepts suggest that the evaluation of health needs should focus on clinical standards and socio-dental indicators that measure the impact of health/disease on the individual quality of life. Oral health cannot be dissociated from general health. This study evaluates a possible association between oral health status, body size, self-perception of oral health, self-perception of body size and dissatisfaction with body image in prepubertal children with mixed dentition, targeting the completion of children's health status assessment which will further allow the identification of individuals at risk and could be further used as an evaluation of the need for specific interventions. The present study is cross-sectional in design and uses data from 710 pre-pubertal children with mixed dentition. The outcome variables comprised one item self-perception of oral health: dmft/DMFT Index and Dental Aesthetic Index, body size, self-assessed body size and desired body size. Multiple logistic regression analyses were performed. The level of significance was set at 5%. More than a half (53.1%) of the participants with mixed dentition reported that their oral health was excellent or very good. In the unadjusted model, untreated decayed teeth, dmft score and body dissatisfaction levels had a significant contribution to poor self-perception of oral health, but after adjustment for gender, BMI status, dmft score, DMFT score and DAI score, only untreated decayed teeth OR = 1.293, 95%CI (1.120-1.492) and higher body dissatisfaction levels had a significant contribution. It was concluded that the need for dental treatment influenced self-perception of oral health in prepubertal children with mixed dentition, especially with relation to untreated decayed teeth. Since only body dissatisfaction levels, but not BMI, were related to poor self-perception of oral health, which involves a psychological component, further studies should evaluate the risk factors of body dissatisfaction, in order to plan health care directed to this age group, and with the purpose to positive parenting strategies.

Selective spatial enhancement: Attentional spotlight size impacts spatial but not temporal perception.

PubMed

Goodhew, Stephanie C; Shen, Elizabeth; Edwards, Mark

2016-08-01

An important but often neglected aspect of attention is how changes in the attentional spotlight size impact perception. The zoom-lens model predicts that a small ("focal") attentional spotlight enhances all aspects of perception relative to a larger ("diffuse" spotlight). However, based on the physiological properties of the two major classes of visual cells (magnocellular and parvocellular neurons) we predicted trade-offs in spatial and temporal acuity as a function of spotlight size. Contrary to both of these accounts, however, across two experiments we found that attentional spotlight size affected spatial acuity, such that spatial acuity was enhanced for a focal relative to a diffuse spotlight, whereas the same modulations in spotlight size had no impact on temporal acuity. This likely reflects the function of attention: to induce the high spatial resolution of the fovea in periphery, where spatial resolution is poor but temporal resolution is good. It is adaptive, therefore, for the attentional spotlight to enhance spatial acuity, whereas enhancing temporal acuity does not confer the same benefit.

Relationship Between Auditory Context and Visual Distance Perception: Effect of Musical Expertise in the Ability to Translate Reverberation Cues Into Room-Size Perception.

PubMed

Etchemendy, Pablo E; Spiousas, Ignacio; Vergara, Ramiro

2018-01-01

In a recently published work by our group [ Scientific Reports, 7, 7189 (2017)], we performed experiments of visual distance perception in two dark rooms with extremely different reverberation times: one anechoic ( T ∼ 0.12 s) and the other reverberant ( T ∼ 4 s). The perceived distance of the targets was systematically greater in the reverberant room when contrasted to the anechoic chamber. Participants also provided auditorily perceived room-size ratings which were greater for the reverberant room. Our hypothesis was that distance estimates are affected by room size, resulting in farther responses for the room perceived larger. Of much importance to the task was the subjects' ability to infer room size from reverberation. In this article, we report a postanalysis showing that participants having musical expertise were better able to extract and translate reverberation cues into room-size information than nonmusicians. However, the degree to which musical expertise affects visual distance estimates remains unclear.

Correlates of Ideal Body Size among Black and White Adolescents

ERIC Educational Resources Information Center

Nollen, Nicole; Kaur, Harsohena; Pulvers, Kim; Choi, Won; Fitzgibbon, Marian; Li, Chaoyang; Nazir, Niaman; Ahluwalia, Jasjit S.

2006-01-01

Cultural differences have been found in body image perceptions among Black and White adolescents, however little is known about the factors associated with perceptions of an ideal body size (IBS). This study examined differences in correlates of IBS among 265 Black (116 girls and 62 boys) and White (63 girls and 24 boys) adolescents. IBS for White…

Putting to a bigger hole: Golf performance relates to perceived size

PubMed Central

Witt, Jessica K.; Linkenauger, Sally A.; Bakdash, Jonathan Z.; Proffitt, Dennis R.

2011-01-01

When engaged in a skilled behaviour such as occurs in sports, people's perceptions relate optical information to their performance. In current research we demonstrate the effects of performance on size perception in golfers. We found golfers who played better judged the hole to be bigger than golfers who did not play as well (Study 1). In follow-up laboratory experiments, participants putted on a golf mat from a location near or far from the hole then judged the size of the hole. Participants who putted from the near location perceived the hole to be bigger than participants who putted from the far location. Our results demonstrate that perception is influenced by the perceiver's current ability to act effectively in the environment. PMID:18567258

The perceptual homunculus: the perception of the relative proportions of the human body.

PubMed

Linkenauger, Sally A; Wong, Hong Yu; Geuss, Michael; Stefanucci, Jeanine K; McCulloch, Kathleen C; Bülthoff, Heinrich H; Mohler, Betty J; Proffitt, Dennis R

2015-02-01

Given that observing one's body is ubiquitous in experience, it is natural to assume that people accurately perceive the relative sizes of their body parts. This assumption is mistaken. In a series of studies, we show that there are dramatic systematic distortions in the perception of bodily proportions, as assessed by visual estimation tasks, where participants were asked to compare the lengths of two body parts. These distortions are not evident when participants estimate the extent of a body part relative to a noncorporeal object or when asked to estimate noncorporal objects that are the same length as their body parts. Our results reveal a radical asymmetry in the perception of corporeal and noncorporeal relative size estimates. Our findings also suggest that people visually perceive the relative size of their body parts as a function of each part's relative tactile sensitivity and physical size.

Effects of an integrated geriatric group balance class within an entry-level Doctorate of Physical Therapy program on students' perceptions of geriatrics and geriatric education in the United States.

PubMed

Reneker, Jennifer C; Weems, Kyra; Scaia, Vincent

2016-01-01

This study was aimed at determining the effect of an integrated group balance class for community-dwelling older adults within entry-level physical therapist coursework on student perceptions of geriatric physical therapy and geriatric physical therapy education. Twenty-nine Doctor of Physical Therapy (DPT) students, 21-33 years old, in their second year of coursework in 2012, participated in an integrated clinical experience with exposure to geriatric patients at an outpatient facility at the Louis Stokes Cleveland Department of Veterans Affairs Medical Center in Akron, Ohio, USA. Student perceptions were collected before and after participation in the 8-week balance class. The Wilcoxon sign-ranked test was used to identify differences in perceptions after participation in the group balance class. Cohen's d values were calculated to measure the size of the pre-participation to post-participation effect for each measure. At the conclusion of the group class, the DPT students demonstrated an increase in positive perceptions of geriatric physical therapy in 8 measures, with small effect sizes (d=0.15-0.30). Two perceptions of geriatric physical therapy demonstrated a significant positive increase (P<.05) with moderate effect sizes (d=0.47 and d=0.50). The students' perceptions of geriatric education in the curriculum demonstrated a large positive effect for quality (d=1.68) and enjoyment (d=1.96). Positive changes were found in most of the perceptions of geriatrics and geriatric education after participation, suggesting that integrated clinical experiences with geriatric patients are an effective way to positively influence perceptions of physical therapist practice with older adults.

Differences in the effects of crowding on size perception and grip scaling in densely cluttered 3-D scenes.

PubMed

Chen, Juan; Sperandio, Irene; Goodale, Melvyn Alan

2015-01-01

Objects rarely appear in isolation in natural scenes. Although many studies have investigated how nearby objects influence perception in cluttered scenes (i.e., crowding), none has studied how nearby objects influence visually guided action. In Experiment 1, we found that participants could scale their grasp to the size of a crowded target even when they could not perceive its size, demonstrating for the first time that neurologically intact participants can use visual information that is not available to conscious report to scale their grasp to real objects in real scenes. In Experiments 2 and 3, we found that changing the eccentricity of the display and the orientation of the flankers had no effect on grasping but strongly affected perception. The differential effects of eccentricity and flanker orientation on perception and grasping show that the known differences in retinotopy between the ventral and dorsal streams are reflected in the way in which people deal with targets in cluttered scenes. © The Author(s) 2014.

Emotion perception and empathy: An individual differences test of relations.

PubMed

Olderbak, Sally; Wilhelm, Oliver

2017-10-01

Numerous theories posit a positive relation between perceiving emotion expressed in the face of a stranger (emotion perception) and feeling or cognitively understanding the emotion of that person (affective and cognitive empathy, respectively). However, when relating individual differences in emotion perception with individual differences in affective or cognitive empathy, effect sizes are contradictory, but often not significantly different from zero. Based on 4 studies (study ns range from 97 to 486 persons; n total = 958) that differ from one another on many design and sample characteristics, applying advanced modeling techniques to control for measurement error, we estimate relations between affective empathy, cognitive empathy, and emotion perception. Relations are tested separately for each of the 6 basic emotions (an emotion-specific model) as well as across all emotions (an emotion-general model). Reflecting the literature, effect sizes and statistical significance with an emotion-general model vary across the individual studies (rs range from -.001 to .24 for emotion perception with affective empathy and -.01 to .39 for emotion perception with cognitive empathy), with a meta-analysis of these results indicating emotion perception is weakly related with affective (r = .13, p = .003) and cognitive empathy (r = .13, p = .05). Relations are not strengthened in an emotion-specific model. We argue that the weak effect sizes and inconsistency across studies reflects a neglected distinction of measurement approach-specifically, empathy is assessed as typical behavior and emotion perception is assessed as maximal effort-and conclude with considerations regarding the measurement of each construct. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Proprioceptive Distance Cues Restore Perfect Size Constancy in Grasping, but Not Perception, When Vision Is Limited.

PubMed

Chen, Juan; Sperandio, Irene; Goodale, Melvyn Alan

2018-03-19

Our brain integrates information from multiple modalities in the control of behavior. When information from one sensory source is compromised, information from another source can compensate for the loss. What is not clear is whether the nature of this multisensory integration and the re-weighting of different sources of sensory information are the same across different control systems. Here, we investigated whether proprioceptive distance information (position sense of body parts) can compensate for the loss of visual distance cues that support size constancy in perception (mediated by the ventral visual stream) [1, 2] versus size constancy in grasping (mediated by the dorsal visual stream) [3-6], in which the real-world size of an object is computed despite changes in viewing distance. We found that there was perfect size constancy in both perception and grasping in a full-viewing condition (lights on, binocular viewing) and that size constancy in both tasks was dramatically disrupted in the restricted-viewing condition (lights off; monocular viewing of the same but luminescent object through a 1-mm pinhole). Importantly, in the restricted-viewing condition, proprioceptive cues about viewing distance originating from the non-grasping limb (experiment 1) or the inclination of the torso and/or the elbow angle of the grasping limb (experiment 2) compensated for the loss of visual distance cues to enable a complete restoration of size constancy in grasping but only a modest improvement of size constancy in perception. This suggests that the weighting of different sources of sensory information varies as a function of the control system being used. Copyright © 2018 Elsevier Ltd. All rights reserved.

Perception of ensemble statistics requires attention.

PubMed

Jackson-Nielsen, Molly; Cohen, Michael A; Pitts, Michael A

2017-02-01

To overcome inherent limitations in perceptual bandwidth, many aspects of the visual world are represented as summary statistics (e.g., average size, orientation, or density of objects). Here, we investigated the relationship between summary (ensemble) statistics and visual attention. Recently, it was claimed that one ensemble statistic in particular, color diversity, can be perceived without focal attention. However, a broader debate exists over the attentional requirements of conscious perception, and it is possible that some form of attention is necessary for ensemble perception. To test this idea, we employed a modified inattentional blindness paradigm and found that multiple types of summary statistics (color and size) often go unnoticed without attention. In addition, we found attentional costs in dual-task situations, further implicating a role for attention in statistical perception. Overall, we conclude that while visual ensembles may be processed efficiently, some amount of attention is necessary for conscious perception of ensemble statistics. Copyright © 2016 Elsevier Inc. All rights reserved.

Weight status and the perception of body image in men

PubMed Central

Gardner, Rick M

2014-01-01

Understanding the role of body size in relation to the accuracy of body image perception in men is an important topic because of the implications for avoiding and treating obesity, and it may serve as a potential diagnostic criterion for eating disorders. The early research on this topic produced mixed findings. About one-half of the early studies showed that obese men overestimated their body size, with the remaining half providing accurate estimates. Later, improvements in research technology and methodology provided a clearer indication of the role of weight status in body image perception. Research in our laboratory has also produced diverse findings, including that obese subjects sometimes overestimate their body size. However, when examining our findings across several studies, obese subjects had about the same level of accuracy in estimating their body size as normal-weight subjects. Studies in our laboratory also permitted the separation of sensory and nonsensory factors in body image perception. In all but one instance, no differences were found overall between the ability of obese and normal-weight subjects to detect overall changes in body size. Importantly, however, obese subjects are better at detecting changes in their body size when the image is distorted to be too thin as compared to too wide. Both obese and normal-weight men require about a 3%–7% change in the width of their body size in order to detect the change reliably. Correlations between a range of body mass index values and body size estimation accuracy indicated no relationship between these variables. Numerous studies in other laboratories asked men to place their body size into discrete categorizes, ranging from thin to obese. Researchers found that overweight and obese men underestimate their weight status, and that men are less accurate in their categorizations than are women. Cultural influences have been found to be important, with body size underestimations occurring in cultures where a larger body is found to be desirable. Methodological issues are reviewed with recommendations for future studies. PMID:25114606

The size-weight illusion induced through human echolocation.

PubMed

Buckingham, Gavin; Milne, Jennifer L; Byrne, Caitlin M; Goodale, Melvyn A

2015-02-01

Certain blind individuals have learned to interpret the echoes of self-generated sounds to perceive the structure of objects in their environment. The current work examined how far the influence of this unique form of sensory substitution extends by testing whether echolocation-induced representations of object size could influence weight perception. A small group of echolocation experts made tongue clicks or finger snaps toward cubes of varying sizes and weights before lifting them. These echolocators experienced a robust size-weight illusion. This experiment provides the first demonstration of a sensory substitution technique whereby the substituted sense influences the conscious perception through an intact sense. © The Author(s) 2014.

Body-size perception, body-esteem, and parenting history in college women reporting a history of child abuse.

PubMed

Eubanks, Jessica R; Kenkel, Michaela Y; Gardner, Rick M

2006-04-01

This study investigated the relations among physical, emotional, and sexual abuse up to adolescence and subsequent perception of body size, detection of changes in body size, and body-esteem. The role of parenting history in abused participants was also examined. 38 college undergraduate women, half of whom had been abused, reported instances of abuse, childhood parenting history, and current body-esteem. A recently developed software program of Gardner and Boice was used to present a series of distorted frontal profiles of each participant's own body for the women to rate as being too wide or too thin. A psychophysical procedure called adaptive probit estimation was used to measure the amount of over- and underestimation of these ratings and whether these changes were statistically significant. Analysis showed abused participants had distorted perceptions of body size, although the direction of the distortion was not consistent. There was no difference in detection of changes in body size. Abused and nonabused participants differed on measures of body-esteem and on ratings of most parenting experiences, including experiences with both mothers and fathers.

A Cross-Cultural Study of Italian and U.S. Children's Perceptions of Interethnic and Interracial Friendships in Two Urban Schools

ERIC Educational Resources Information Center

Pica-Smith, Cinzia; Antognazza, Davide; Marland, Joshua J.; Crescentini, Alberto

2017-01-01

This cross-cultural and cross-sectional study investigated Italian and US children's perceptions of interethnic and interracial friendships, also known as intergroup friendships. A total sample of 226 children attending two urban, elementary schools in a middle-sized Northeastern US city and a middle-sized northern Italian city, were interviewed…

Validation of a food quantification picture book and portion sizes estimation applying perception and memory methods.

PubMed

Szenczi-Cseh, J; Horváth, Zs; Ambrus, Á

2017-12-01

We tested the applicability of EPIC-SOFT food picture series used in the context of a Hungarian food consumption survey gathering data for exposure assessment, and investigated errors in food portion estimation resulted from the visual perception and conceptualisation-memory. Sixty-two participants in three age groups (10 to <74 years) were presented with three different portion sizes of five foods. The results were considered acceptable if the relative difference between average estimated and actual weight obtained through the perception method was ≤25%, and the relative standard deviation of the individual weight estimates was <30% after compensating the effect of potential outliers with winsorisation. Picture series for all five food items were rated acceptable. Small portion sizes were tended to be overestimated, large ones were tended to be underestimated. Portions of boiled potato and creamed spinach were all over- and underestimated, respectively. Recalling the portion sizes resulted in overestimation with larger differences (up to 60.7%).

Comparing fishers' and scientific estimates of size at maturity and maximum body size as indicators for overfishing.

PubMed

Mclean, Elizabeth L; Forrester, Graham E

2018-04-01

We tested whether fishers' local ecological knowledge (LEK) of two fish life-history parameters, size at maturity (SAM) at maximum body size (MS), was comparable to scientific estimates (SEK) of the same parameters, and whether LEK influenced fishers' perceptions of sustainability. Local ecological knowledge was documented for 82 fishers from a small-scale fishery in Samaná Bay, Dominican Republic, whereas SEK was compiled from the scientific literature. Size at maturity estimates derived from LEK and SEK overlapped for most of the 15 commonly harvested species (10 of 15). In contrast, fishers' maximum size estimates were usually lower than (eight species), or overlapped with (five species) scientific estimates. Fishers' size-based estimates of catch composition indicate greater potential for overfishing than estimates based on SEK. Fishers' estimates of size at capture relative to size at maturity suggest routine inclusion of juveniles in the catch (9 of 15 species), and fishers' estimates suggest that harvested fish are substantially smaller than maximum body size for most species (11 of 15 species). Scientific estimates also suggest that harvested fish are generally smaller than maximum body size (13 of 15), but suggest that the catch is dominated by adults for most species (9 of 15 species), and that juveniles are present in the catch for fewer species (6 of 15). Most Samaná fishers characterized the current state of their fishery as poor (73%) and as having changed for the worse over the past 20 yr (60%). Fishers stated that concern about overfishing, catching small fish, and catching immature fish contributed to these perceptions, indicating a possible influence of catch-size composition on their perceptions. Future work should test this link more explicitly because we found no evidence that the minority of fishers with more positive perceptions of their fishery reported systematically different estimates of catch-size composition than those with the more negative majority view. Although fishers' and scientific estimates of size at maturity and maximum size parameters sometimes differed, the fact that fishers make routine quantitative assessments of maturity and body size suggests potential for future collaborative monitoring efforts to generate estimates usable by scientists and meaningful to fishers. © 2017 by the Ecological Society of America.

The role of underestimating body size for self-esteem and self-efficacy among grade five children in Canada.

PubMed

Maximova, Katerina; Khan, Mohammad K A; Austin, S Bryn; Kirk, Sara F L; Veugelers, Paul J

2015-10-01

Underestimating body size hinders healthy behavior modification needed to prevent obesity. However, initiatives to improve body size misperceptions may have detrimental consequences on self-esteem and self-efficacy. Using sex-specific multiple mixed-effect logistic regression models, we examined the association of underestimating versus accurate body size perceptions with self-esteem and self-efficacy in a provincially representative sample of 5075 grade five school children. Body size perceptions were defined as the standardized difference between the body mass index (BMI, from measured height and weight) and self-perceived body size (Stunkard body rating scale). Self-esteem and self-efficacy for physical activity and healthy eating were self-reported. Most of overweight boys and girls (91% and 83%); and most of obese boys and girls (93% and 90%) underestimated body size. Underestimating weight was associated with greater self-efficacy for physical activity and healthy eating among normal-weight children (odds ratio: 1.9 and 1.6 for boys, 1.5 and 1.4 for girls) and greater self-esteem among overweight and obese children (odds ratio: 2.0 and 6.2 for boys, 2.0 and 3.4 for girls). Results highlight the importance of developing optimal intervention strategies as part of targeted obesity prevention efforts that de-emphasize the focus on body weight, while improving body size perceptions. Copyright © 2015 Elsevier Inc. All rights reserved.

Clients' and workers' perceptions on clients' functional ability and need for help: home care in municipalities.

PubMed

Hammar, Teija; Perälä, Marja-Leena; Rissanen, Pekka

2009-03-01

The aim of the study was to compare clients' and named home care (HC) workers' perceptions of clients' functional ability (FA) and need for help and to analyse which client- and municipality-related factors are associated with perceptions of client's FA. The total of 686 Finnish HC clients was interviewed in 2001. Further, the questionnaire was sent to 686 HC workers. FA was assessed by activities of daily living (ADL), which included both basic/physical (PADL) and instrumental (IADL) activities. The association between client's FA and municipality-related variables was analysed by using hierarchical logistic regression models. The findings indicated that clients' and HC-workers' perceptions about what the clients were able to do were similar in the PADL functions, but perceptions differed when it comes to the IADL functions for mobility and in climbing stairs. A smaller proportion of clients compared with HC workers assessed themselves to be in need of help in all ADL functions. Use of home help and bathing services increased the probability of belonging to the 'poor' FA class while living alone and small size of municipality decreased the probability. The study indicates that although clients and workers assessed client's FA fairly similarly, there were major differences in perceptions concerning clients' needs for help in ADL functions. Clients' and workers' shared view of need for help forms a basis for high-quality care. Therefore, the perception of both the clients and workers must be taken into account when planning care and services. There was also variation in clients' FA between municipalities, although only the size of municipality had some association with the variation. The probability that clients with a lower FA are cared for in HC is higher if the clients live in large- rather than small-sized municipalities. This may reflect a better mix of services and resources in large-sized municipalities.

Towards a perceptive understanding of size in cellular biology.

PubMed

Zoppè, Monica

2017-06-29

Cells are minute-typically too small to be seen by the human eye. Even so, the cellular world encompasses a range of scales, from roughly a tenth of a nanometer (10 -10 m) to a millimeter (10 -3 m) or larger, spanning seven orders of magnitude or more. Because they are so far from our experience, it is difficult for us to envision such scales. To help our imagination grasp such dimensions, I propose the adoption of a 'perceptive scale' that can facilitate a more direct experience of cellular sizes. From this, as I argue below, will stem a new perception also of biological shape, cellular space and dynamic processes.

Neural dynamics of motion processing and speed discrimination.

PubMed

Chey, J; Grossberg, S; Mingolla, E

1998-09-01

A neural network model of visual motion perception and speed discrimination is presented. The model shows how a distributed population code of speed tuning, that realizes a size-speed correlation, can be derived from the simplest mechanisms whereby activations of multiple spatially short-range filters of different size are transformed into speed-turned cell responses. These mechanisms use transient cell responses to moving stimuli, output thresholds that covary with filter size, and competition. These mechanisms are proposed to occur in the V1-->MT cortical processing stream. The model reproduces empirically derived speed discrimination curves and simulates data showing how visual speed perception and discrimination can be affected by stimulus contrast, duration, dot density and spatial frequency. Model motion mechanisms are analogous to mechanisms that have been used to model 3-D form and figure-ground perception. The model forms the front end of a larger motion processing system that has been used to simulate how global motion capture occurs, and how spatial attention is drawn to moving forms. It provides a computational foundation for an emerging neural theory of 3-D form and motion perception.

Affective and physiological correlates of the perception of unimodal and bimodal emotional stimuli.

PubMed

Rosa, Pedro J; Oliveira, Jorge; Alghazzawi, Daniyal; Fardoun, Habib; Gamito, Pedro

2017-08-01

Despite the multisensory nature of perception, previous research on emotions has been focused on unimodal emotional cues with visual stimuli. To the best of our knowledge, there is no evidence on the extent to which incongruent emotional cues from visual and auditory sensory channels affect pupil size. To investigate the effects of audiovisual emotional information perception on the physiological and affective response, but also to determine the impact of mismatched cues in emotional perception on these physiological indexes. Pupil size, electrodermal activity and affective subjective responses were recorded while 30 participants were exposed to visual and auditory stimuli with varied emotional content in three different experimental conditions: pictures and sounds presented alone (unimodal), emotionally matched audio-visual stimuli (bimodal congruent) and emotionally mismatched audio-visual stimuli (bimodal incongruent). The data revealed no effect of emotional incongruence on physiological and affective responses. On the other hand, pupil size covaried with skin conductance response (SCR), but the subjective experience was partially dissociated from autonomic responses. Emotional stimuli are able to trigger physiological responses regardless of valence, sensory modality or level of emotional congruence.

Relative size perception at a distance is best at eye level

NASA Technical Reports Server (NTRS)

Bertamini, M.; Yang, T. L.; Proffitt, D. R.; Kaiser, M. K. (Principal Investigator)

1998-01-01

Relative size judgments were collected for two objects at 30.5 m and 23.8 from the observer in order to assess how performance depends on the relationship between the size of the objects and the eye level of the observer. In three experiments in an indoor hallway and in one experiment outdoors, accuracy was higher for objects in the neighborhood of eye level. We consider these results in the light of two hypotheses. One proposes that observers localize the horizon as a reference for judging relative size, and the other proposes that observers perceive the general neighborhood of the horizon and then employ a height-in-visual-field heuristic. The finding that relative size judgments are best around the horizon implies that information that is independent of distance perception is used in perceiving size.

The Ebbinghaus Illusion Deceives Adults but Not Young Children

ERIC Educational Resources Information Center

Doherty, Martin J.; Campbell, Nicola M.; Tsuji, Hiromi; Phillips, William A.

2010-01-01

The sensitivity of size perception to context has been used to distinguish between "vision for action" and "vision for perception", and to study cultural, psychopathological, and developmental differences in perception. The status of that evidence is much debated, however. Here we use a rigorous double dissociation paradigm based on the Ebbinghaus…

Student Perceptions of Social Justice and Social Justice Activities

ERIC Educational Resources Information Center

Torres-Harding, Susan R.; Steele, Cheronda; Schulz, Erica; Taha, Farah; Pico, Chantal

2014-01-01

Encouraging students to engage in activities that actively seek to promote social justice is a goal of many educators. This study analyzed college student perceptions around social justice and related activities in a medium-sized, urban university in the United States. Students' open-ended responses to questions assessing their perceptions of…

Body size preference and body weight perception among two migrant groups of non-Western origin.

PubMed

Nicolaou, Mary; Doak, Colleen; Dam, Rob van; Hosper, Karen; Seidell, Jaap; Stronks, Karien

2008-12-01

To evaluate body size preference, body weight perception and their relationship with actual weight in two migrant groups of non-Western origin, Turks and Moroccans; additionally, to study the association between body size preference and acculturation. Cross-sectional study. Amsterdam, The Netherlands. Males and females (18-30 years) were randomly selected from the population registry (n 451); participants, or at least one of their parents, were born in Turkey or Morocco. Body size preference was assessed using seven silhouette drawings and body weight perception was assessed by asking participants' opinion of own weight. Acculturation variables were generation status and two scale measures, cultural orientation and social contacts. Participants showed preference for a thin body size. The discrepancy between ideal and current size was significant in women but not men (P < 0.001). Perceived current body size was correlated with BMI (Spearman's correlation coefficient 0.60, P < 0.001 (men) and 0.73, P < 0.001 (women)). Among overweight participants (BMI = 25.0-29.9 kg/m2), 63-82 % of men and 35 % of women perceived themselves as 'average'. Paying attention to own body weight was associated with a discrepancy between ideal and current size among women and with perceiving oneself as 'overweight' among men. Body size preference was not significantly associated with the three acculturation variables. We did not observe a preference for large body sizes in these two non-Western migrant groups. Similar to Western populations, most women wished to be thinner than they were. This was not the case among men, the majority of whom were also unaware of being overweight.

Distance and Size Perception in Astronauts during Long-Duration Spaceflight

PubMed Central

Clément, Gilles; Skinner, Anna; Lathan, Corinna

2013-01-01

Exposure to microgravity during spaceflight is known to elicit orientation illusions, errors in sensory localization, postural imbalance, changes in vestibulo-spinal and vestibulo-ocular reflexes, and space motion sickness. The objective of this experiment was to investigate whether an alteration in cognitive visual-spatial processing, such as the perception of distance and size of objects, is also taking place during prolonged exposure to microgravity. Our results show that astronauts on board the International Space Station exhibit biases in the perception of their environment. Objects’ heights and depths were perceived as taller and shallower, respectively, and distances were generally underestimated in orbit compared to Earth. These changes may occur because the perspective cues for depth are less salient in microgravity or the eye-height scaling of size is different when an observer is not standing on the ground. This finding has operational implications for human space exploration missions. PMID:25369884

"Whatever average is:" understanding African-American mothers' perceptions of infant weight, growth, and health.

PubMed

Thompson, Amanda L; Adair, Linda; Bentley, Margaret E

2014-06-01

Biomedical researchers have raised concerns that mothers' inability to recognize infant and toddler overweight poses a barrier to stemming increasing rates of overweight and obesity, particularly among low-income or minority mothers. Little anthropological research has examined the sociocultural, economic or structural factors shaping maternal perceptions of infant and toddler size or addressed biomedical depictions of maternal misperception as a "socio-cultural problem." We use qualitative and quantitative data from 237 low-income, African-American mothers to explore how they define 'normal' infant growth and infant overweight. Our quantitative results document that mothers' perceptions of infant size change with infant age, are sensitive to the size of other infants in the community, and are associated with concerns over health and appetite. Qualitative analysis documents that mothers are concerned with their children's weight status and assess size in relation to their infants' cues, local and societal norms of appropriate size, interactions with biomedicine, and concerns about infant health and sufficiency. These findings suggest that mothers use multiple models to interpret and respond to child weight. An anthropological focus on the complex social and structural factors shaping what is considered 'normal' and 'abnormal' infant weight is critical for shaping appropriate and successful interventions.

Perception of biological motion from size-invariant body representations.

PubMed

Lappe, Markus; Wittinghofer, Karin; de Lussanet, Marc H E

2015-01-01

The visual recognition of action is one of the socially most important and computationally demanding capacities of the human visual system. It combines visual shape recognition with complex non-rigid motion perception. Action presented as a point-light animation is a striking visual experience for anyone who sees it for the first time. Information about the shape and posture of the human body is sparse in point-light animations, but it is essential for action recognition. In the posturo-temporal filter model of biological motion perception posture information is picked up by visual neurons tuned to the form of the human body before body motion is calculated. We tested whether point-light stimuli are processed through posture recognition of the human body form by using a typical feature of form recognition, namely size invariance. We constructed a point-light stimulus that can only be perceived through a size-invariant mechanism. This stimulus changes rapidly in size from one image to the next. It thus disrupts continuity of early visuo-spatial properties but maintains continuity of the body posture representation. Despite this massive manipulation at the visuo-spatial level, size-changing point-light figures are spontaneously recognized by naive observers, and support discrimination of human body motion.

Sex and Sibling Structure: Interaction Effects upon the Accuracy of Adolescent Perceptions of Parental Orientations.

ERIC Educational Resources Information Center

Smith, Thomas Ewin

1984-01-01

Surveyed 291 mother-child and 221 father-child dyads to examine adolescent perceptions of parental educational goals. Results showed family size and student's age had no effect, but birth order and sibling sex composition interact with sex of the parent and the adolescent in effects on accuracy of perception. (JAC)

Self body-size perception in an insect

NASA Astrophysics Data System (ADS)

Ben-Nun, Amir; Guershon, Moshe; Ayali, Amir

2013-05-01

Animals negotiating complex environments encounter a wide range of obstacles of different shapes and sizes. It is greatly beneficial for the animal to react to such obstacles in a precise, context-specific manner, in order to avoid harm or even simply to minimize energy expenditure. An essential key challenge is, therefore, an estimation of the animal's own physical characteristics, such as body size. A further important aspect of self body-size perception (or SBSP) is the need to update it in accordance with changes in the animal's size and proportions. Despite the major role of SBSP in functional behavior, little is known about if and how it is mediated. Here, we demonstrate that insects are also capable of self perception of body size and that this is a vital factor in allowing them to adjust their behavior following the sudden and dramatic growth associated with periodic molting. We reveal that locusts' SBSP is strongly correlated with their body size. However, we show that the dramatic change in size accompanying adult emergence is not sufficient to create a new and updated SBSP. Rather, this is created and then consolidated only following the individuals' experience and interaction with the physical environment. Behavioral or pharmacological manipulations can both result in maintenance of the old larval SBSP. Our results emphasize the importance of learning and memory-related processes in the development and update of SBSP, and highlight the advantage of insects as good models for a detailed study on the neurobiological and molecular aspects of SBSP.

The perception of depth from binocular disparity.

DOT National Transportation Integrated Search

1963-05-01

This study was concerned with the factors involved in the perception of depth from a binocular disparity. A binocularly observed configuration of constant convergences, constant visual size, and having constant binocular disparities was made to appea...

Assessment of body perception among Swedish adolescents and young adults.

PubMed

Bergström, E; Stenlund, H; Svedjehäll, B

2000-01-01

To assess body perception in adolescents and young adults without anorexia nervosa. Using a visual size estimation technique, perceived body size was estimated in four groups of Swedish adolescents and young adults without anorexia nervosa (86 males and 95 females). Perceived body size was estimated at nine different body sites comparing these estimations to real body size. The results show that 95% of males and 96% of females overestimated their body size (mean overestimation: males +22%, females +33%). The overestimations were greatest in females. The greatest overestimations were made of the waist (males +31%, females +46%), buttocks (males +22%, females +42%), and thighs (males +27%, females +41%). The results indicate that overestimation of body size may be a general phenomenon in adolescents and young adults in a country such as Sweden, implying a similar, but less pronounced distortion of body image as in individuals with anorexia nervosa.

Big Money: The Effect of Money Size on Value Perceptions and Saving Motivation.

PubMed

Peetz, Johanna; Soliman, Monica

2016-01-28

Motivated perception has been shown to affect people's estimates of money (e.g., perceiving coins as larger than real size). In the present research, we examine whether simply varying the size of a picture of money can affect its perceived value and subsequent decisions. Participants presented with a picture of money enlarged by 15% perceived the depicted money as more valuable compared with those seeing a real-size picture (Study 1). When told to imagine their own cash and banked money in the depicted form, participants presented with a picture enlarged by 15% felt more subjectively wealthy and reported fewer intentions to conserve their money compared with those seeing a real-size picture of the same money (Study 2). Together, these studies suggest that judgments about money and even attitudes toward personal spending can be influenced by manipulating the size of a picture of money. © The Author(s) 2016.

Human-resource professionals' perceptions of organizational politics as a function of experience, organizational size, and perceived independence.

PubMed

Conner, Deondra S

2006-12-01

The author examined human-resource professionals' occupation-related and general work experience, socialization from participation in professional activities, organizational size, and perceived independence as predictors of perceptions of organizational politics (POPS). Results varied with the author's use of the overall POPS scale (K. M. Kacmar & G. R. Ferris, 1991) vs. a more specific subscale that measured perceptions related to such issues as pay- and promotion-related politics. It was most notable that work experience appeared to have an inverse relationship with POPS among human-resource professionals in the area of pay and promotions. The author discussed results in relation to the implications and directions for future research.

Acoustic Properties Predict Perception of Unfamiliar Dutch Vowels by Adult Australian English and Peruvian Spanish Listeners

PubMed Central

Alispahic, Samra; Mulak, Karen E.; Escudero, Paola

2017-01-01

Research suggests that the size of the second language (L2) vowel inventory relative to the native (L1) inventory may affect the discrimination and acquisition of L2 vowels. Models of non-native and L2 vowel perception stipulate that naïve listeners' non-native and L2 perceptual patterns may be predicted by the relationship in vowel inventory size between the L1 and the L2. Specifically, having a smaller L1 vowel inventory than the L2 impedes L2 vowel perception, while having a larger one often facilitates it. However, the Second Language Linguistic Perception (L2LP) model specifies that it is the L1–L2 acoustic relationships that predict non-native and L2 vowel perception, regardless of L1 vowel inventory. To test the effects of vowel inventory size vs. acoustic properties on non-native vowel perception, we compared XAB discrimination and categorization of five Dutch vowel contrasts between monolinguals whose L1 contains more (Australian English) or fewer (Peruvian Spanish) vowels than Dutch. No effect of language background was found, suggesting that L1 inventory size alone did not account for performance. Instead, participants in both language groups were more accurate in discriminating contrasts that were predicted to be perceptually easy based on L1–L2 acoustic relationships, and were less accurate for contrasts likewise predicted to be difficult. Further, cross-language discriminant analyses predicted listeners' categorization patterns which in turn predicted listeners' discrimination difficulty. Our results show that listeners with larger vowel inventories appear to activate multiple native categories as reflected in lower accuracy scores for some Dutch vowels, while listeners with a smaller vowel inventory seem to have higher accuracy scores for those same vowels. In line with the L2LP model, these findings demonstrate that L1–L2 acoustic relationships better predict non-native and L2 perceptual performance and that inventory size alone is not a good predictor for cross-language perceptual difficulties. PMID:28191001

Differentiation of nonneoplastic and neoplastic gallbladder polyps 1 cm or bigger with multi-detector row computed tomography.

PubMed

Park, Ko Woon; Kim, Seong Hyun; Choi, Seong Ho; Lee, Won Jae

2010-01-01

To evaluate useful computed tomographic features to differentiate nonneoplastic and neoplastic gallbladder polyps 1 cm or bigger. Thirty-one patients with 32 nonneoplastic polyps and 67 patients with 73 neoplastic polyps 1 cm or bigger underwent unenhanced and dual-phase (arterial and portal venous phases) multi-detector row computed tomography. Gallbladder polyps were diagnosed by cholecystectomy. Computed tomographic features including size (1.5 cm), surface (smooth or irregular), shape (pedunculated or sessile), accompanying wall thickening, basal indentation, perception on unenhanced images, and enhancement pattern between 2 groups were compared using univariate and multivariate analyses. On univariate analysis, age 55 years or older (P = 0.0019), size bigger than 1.5 cm (P < 0.0001), irregular surface (P = 0.0033), sessile shape (P = 0.0016), accompanying wall thickening (P = 0.0056), basal indentation (P = 0.0236), and perception on unenhanced images (P < 0.0001) were significantly more frequent in neoplastic polyps as compared with nonneoplastic polyps. On multivariate analysis, size bigger than 1.5 cm (P = 0.0260), sessile shape (P = 0.0397), and perception on unenhanced images (P < 0.0001) were statistically significant. Size bigger than 1.5 cm, sessile shape, and perception on unenhanced images are the main factors that differentiate neoplastic from nonneoplastic gallbladder polyps 1 cm or bigger.

Bilateral Symmetry of Distortions of Tactile Size Perception.

PubMed

Longo, Matthew R; Ghosh, Arko; Yahya, Tasneem

2015-01-01

The perceived distance between touches on the limbs is generally bigger for distances oriented across the width of the limb than for distances oriented along the length of the limb. The present study aimed to investigate the coherence of such distortions of tactile size perception across different skin surfaces. We investigated distortions of tactile size perception on the dorsal and palmar surfaces of both the left and right hands as well as the forehead. Participants judged which of two tactile distances felt larger. One distance was aligned with the proximodistal axis (along the body), the other with the mediolateral axis (across the body). Clear distortions were found on all five skin surfaces, with stimuli oriented across the width of the body being perceived as farther apart than those oriented along the length of the body. Consistent with previous results, distortions were smaller on the palmar than on the dorsal hand surface. Distortion on the forehead was intermediate between the dorsal and palmar surfaces. There were clear correlations between distortion on the left and right hands, for both the dorsal and palmar skin surfaces. In contrast, within each hand, there was no significant correlation between the two skin surfaces. Distortion on the forehead was not significantly correlated with that on any of the other skin surfaces. These results provide evidence for bilaterally symmetric representations underlying tactile size perception. © The Author(s) 2015.

Auditory environmental context affects visual distance perception.

PubMed

Etchemendy, Pablo E; Abregú, Ezequiel; Calcagno, Esteban R; Eguia, Manuel C; Vechiatti, Nilda; Iasi, Federico; Vergara, Ramiro O

2017-08-03

In this article, we show that visual distance perception (VDP) is influenced by the auditory environmental context through reverberation-related cues. We performed two VDP experiments in two dark rooms with extremely different reverberation times: an anechoic chamber and a reverberant room. Subjects assigned to the reverberant room perceived the targets farther than subjects assigned to the anechoic chamber. Also, we found a positive correlation between the maximum perceived distance and the auditorily perceived room size. We next performed a second experiment in which the same subjects of Experiment 1 were interchanged between rooms. We found that subjects preserved the responses from the previous experiment provided they were compatible with the present perception of the environment; if not, perceived distance was biased towards the auditorily perceived boundaries of the room. Results of both experiments show that the auditory environment can influence VDP, presumably through reverberation cues related to the perception of room size.

Multi-Positioning Mathematics Class Size: Teachers' Views

ERIC Educational Resources Information Center

Handal, Boris; Watson, Kevin; Maher, Marguerite

2015-01-01

This paper explores mathematics teachers' perceptions about class size and the impact class size has on teaching and learning in secondary mathematics classrooms. It seeks to understand teachers' views about optimal class sizes and their thoughts about the education variables that influence these views. The paper draws on questionnaire responses…

Size cues and the adjacency principle.

DOT National Transportation Integrated Search

1963-11-01

The purpose of the present study was to apply the adjacency principle to the perception of relative depth from size cues. In agreement with the adjacency principle, it was found that the size cue between adjacent objects was more effective than the s...

Perception-action dissociation generalizes to the size-inertia illusion.

PubMed

Platkiewicz, Jonathan; Hayward, Vincent

2014-04-01

Two objects of similar visual aspects and of equal mass, but of different sizes, generally do not elicit the same percept of heaviness in humans. The larger object is consistently felt to be lighter than the smaller, an effect known as the "size-weight illusion." When asked to repeatedly lift the two objects, the grip forces were observed to adapt rapidly to the true object weight while the size-weight illusion persisted, a phenomenon interpreted as a dissociation between perception and action. We investigated whether the same phenomenon can be observed if the mass of an object is available to participants through inertial rather than gravitational cues and if the number and statistics of the stimuli is such that participants cannot remember each individual stimulus. We compared the responses of 10 participants in 2 experimental conditions, where they manipulated 33 objects having uncorrelated masses and sizes, supported by a frictionless, air-bearing slide that could be oriented vertically or horizontally. We also analyzed the participants' anticipatory motor behavior by measuring the grip force before motion onset. We found that the perceptual illusory effect was quantitatively the same in the two conditions and observed that both visual size and haptic mass had a negligible effect on the anticipatory gripping control of the participants in the gravitational and inertial conditions, despite the enormous differences in the mechanics of the two conditions and the large set of uncorrelated stimuli.

Perceptual Averaging in Individuals with Autism Spectrum Disorder.

PubMed

Corbett, Jennifer E; Venuti, Paola; Melcher, David

2016-01-01

There is mounting evidence that observers rely on statistical summaries of visual information to maintain stable and coherent perception. Sensitivity to the mean (or other prototypical value) of a visual feature (e.g., mean size) appears to be a pervasive process in human visual perception. Previous studies in individuals diagnosed with Autism Spectrum Disorder (ASD) have uncovered characteristic patterns of visual processing that suggest they may rely more on enhanced local representations of individual objects instead of computing such perceptual averages. To further explore the fundamental nature of abstract statistical representation in visual perception, we investigated perceptual averaging of mean size in a group of 12 high-functioning individuals diagnosed with ASD using simplified versions of two identification and adaptation tasks that elicited characteristic perceptual averaging effects in a control group of neurotypical participants. In Experiment 1, participants performed with above chance accuracy in recalling the mean size of a set of circles ( mean task ) despite poor accuracy in recalling individual circle sizes ( member task ). In Experiment 2, their judgments of single circle size were biased by mean size adaptation. Overall, these results suggest that individuals with ASD perceptually average information about sets of objects in the surrounding environment. Our results underscore the fundamental nature of perceptual averaging in vision, and further our understanding of how autistic individuals make sense of the external environment.

Objectification in Virtual Romantic Contexts: Perceived Discrepancies between Self and Partner Ideals Differentially affect Body Consciousness in Women and Men

PubMed Central

Overstreet, Nicole M.; Quinn, Diane M.; Marsh, Kerry L.

2015-01-01

The current study examined whether exposure to sexually objectifying images in a potential romantic partner's virtual apartment affects discrepancies between people's perception of their own appearance (i.e., self-perceptions) and their perception of the body ideal that is considered desirable to a romantic partner (i.e., partner-ideals). Participants were 114 heterosexual undergraduate students (57 women and 57 men) from a northeastern U.S. university. The study used a 2 (Participant Gender) x 2 (Virtual Environment: Sexualized vs. Non-Sexualized) between-subjects design. We predicted that women exposed to sexually objectifying images in a virtual environment would report greater discrepancies between their self-perceptions and partner-ideals than men, which in turn would contribute to women's body consciousness. Findings support this hypothesis and show that perceived discrepancies account for the relationship between exposure to sexually objectifying images and body consciousness for women but not men. We also found gender asymmetries in objectification responses when each component of perceived discrepancies, i.e., self-perceptions versus perceptions of a romantic partner's body ideal, were examined separately. For men, exposure to muscular sexualized images was significantly associated with their self-perceptions but not their perceptions of the body size that is considered desirable to a romantic partner. For women, exposure to thin sexualized images was significantly associated with their perceptions that a romantic partner preferred a woman with a smaller body size. However, exposure to these images did not affect women's self-perceptions. Implications for gender asymmetries in objectification responses and perceived discrepancies that include a romantic partner's perceptions are discussed. PMID:26594085

Seeing the body distorts tactile size perception.

PubMed

Longo, Matthew R; Sadibolova, Renata

2013-03-01

Vision of the body modulates somatosensation, even when entirely non-informative about stimulation. For example, seeing the body increases tactile spatial acuity, but reduces acute pain. While previous results demonstrate that vision of the body modulates somatosensory sensitivity, it is unknown whether vision also affects metric properties of touch, and if so how. This study investigated how non-informative vision of the body modulates tactile size perception. We used the mirror box illusion to induce the illusion that participants were directly seeing their stimulated left hand, though they actually saw their reflected right hand. We manipulated whether participants: (a) had the illusion of directly seeing their stimulated left hand, (b) had the illusion of seeing a non-body object at the same location, or (c) looked directly at their non-stimulated right-hand. Participants made verbal estimates of the perceived distance between two tactile stimuli presented simultaneously to the dorsum of the left hand, either 20, 30, or 40mm apart. Vision of the body significantly reduced the perceived size of touch, compared to vision of the object or of the contralateral hand. In contrast, no apparent changes of perceived hand size were found. These results show that seeing the body distorts tactile size perception. Copyright © 2012 Elsevier B.V. All rights reserved.

The Role of Breast Size and Areolar Pigmentation in Perceptions of Women's Sexual Attractiveness, Reproductive Health, Sexual Maturity, Maternal Nurturing Abilities, and Age.

PubMed

Dixson, Barnaby J; Duncan, Melanie; Dixson, Alan F

2015-08-01

Women's breast morphology is thought to have evolved via sexual selection as a signal of maturity, health, and fecundity. While research demonstrates that breast morphology is important in men's judgments of women's attractiveness, it remains to be determined how perceptions might differ when considering a larger suite of mate relevant attributes. Here, we tested how variation in breast size and areolar pigmentation affected perceptions of women's sexual attractiveness, reproductive health, sexual maturity, maternal nurturing abilities, and age. Participants (100 men; 100 women) rated images of female torsos modeled to vary in breast size (very small, small, medium, and large) and areolar pigmentation (light, medium, and dark) for each of the five attributes listed above. Sexual attractiveness ratings increased linearly with breast size, but large breasts were not judged to be significantly more attractive than medium-sized breasts. Small and medium-sized breasts were rated as most attractive if they included light or medium colored areolae, whereas large breasts were more attractive if they had medium or dark areolae. Ratings for perceived age, sexual maturity, and nurturing ability also increased with breast size. Darkening the areolae reduced ratings of the reproductive health of medium and small breasts, whereas it increased ratings for large breasts. There were no significant sex differences in ratings of any of the perceptual measures. These results demonstrate that breast size and areolar pigmentation interact to determine ratings for a suite of sociosexual attributes, each of which may be relevant to mate choice in men and intra-sexual competition in women.

The contribution of cutaneous and kinesthetic sensory modalities in haptic perception of orientation.

PubMed

Frisoli, Antonio; Solazzi, Massimiliano; Reiner, Miriam; Bergamasco, Massimo

2011-06-30

The aim of this study was to understand the integration of cutaneous and kinesthetic sensory modalities in haptic perception of shape orientation. A specific robotic apparatus was employed to simulate the exploration of virtual surfaces by active touch with two fingers, with kinesthetic only, cutaneous only and combined sensory feedback. The cutaneous feedback was capable of displaying the local surface orientation at the contact point, through a small plate indenting the fingerpad at contact. A psychophysics test was conducted with SDT methodology on 6 subjects to assess the discrimination threshold of angle perception between two parallel surfaces, with three sensory modalities and two shape sizes. Results show that the cutaneous sensor modality is not affected by size of shape, but kinesthetic performance is decreasing with smaller size. Cutaneous and kinesthetic sensory cues are integrated according to a Bayesian model, so that the combined sensory stimulation always performs better than single modalities alone. Copyright © 2010 Elsevier Inc. All rights reserved.

The role of early stages of cortical visual processing in size and distance judgment: a transcranial direct current stimulation study.

PubMed

Costa, Thiago L; Costa, Marcelo F; Magalhães, Adsson; Rêgo, Gabriel G; Nagy, Balázs V; Boggio, Paulo S; Ventura, Dora F

2015-02-19

Recent research suggests that V1 plays an active role in the judgment of size and distance. Nevertheless, no research has been performed using direct brain stimulation to address this issue. We used transcranial direct-current stimulation (tDCS) to directly modulate the early stages of cortical visual processing while measuring size and distance perception with a psychophysical scaling method of magnitude estimation in a repeated-measures design. The subjects randomly received anodal, cathodal, and sham tDCS in separate sessions starting with size or distance judgment tasks. Power functions were fit to the size judgment data, whereas logarithmic functions were fit to distance judgment data. Slopes and R(2) were compared with separate repeated-measures analyses of variance with two factors: task (size vs. distance) and tDCS (anodal vs. cathodal vs. sham). Anodal tDCS significantly decreased slopes, apparently interfering with size perception. No effects were found for distance perception. Consistent with previous studies, the results of the size task appeared to reflect a prothetic continuum, whereas the results of the distance task seemed to reflect a metathetic continuum. The differential effects of tDCS on these tasks may support the hypothesis that different physiological mechanisms underlie judgments on these two continua. The results further suggest the complex involvement of the early visual cortex in size judgment tasks that go beyond the simple representation of low-level stimulus properties. This supports predictive coding models and experimental findings that suggest that higher-order visual areas may inhibit incoming information from the early visual cortex through feedback connections when complex tasks are performed. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

An almost general theory of mean size perception.

PubMed

Allik, Jüri; Toom, Mai; Raidvee, Aire; Averin, Kristiina; Kreegipuu, Kairi

2013-05-03

A general explanation for the observer's ability to judge the mean size of simple geometrical figures, such as circles, was advanced. Results indicated that, contrary to what would be predicted by statistical averaging, the precision of mean size perception decreases with the number of judged elements. Since mean size discrimination was insensitive to how total size differences were distributed among individual elements, this suggests that the observer has a limited cognitive access to the size of individual elements pooled together in a compulsory manner before size information reaches awareness. Confirming the associative law of addition means, observers are indeed sensitive to the mean, not the sizes of individual elements. All existing data can be explained by an almost general theory, namely, the Noise and Selection (N&S) Theory, formulated in exact quantitative terms, implementing two familiar psychophysical principles: the size of an element cannot be measured with absolute accuracy and only a limited number of elements can be taken into account in the computation of the average size. It was concluded that the computation of ensemble characteristics is not necessarily a tool for surpassing the capacity limitations of perceptual processing. Copyright © 2013 Elsevier Ltd. All rights reserved.

Body image perceptions in Western and post-communist countries: a cross-cultural pilot study of children and parents.

PubMed

Humenikova, Lenka; Gates, Gail E

2008-07-01

The development of an unrealistic ideal body image and body size dissatisfaction among children is common in Western countries, including the USA and many European nations. However, little is known about children's body image perceptions in post-communist countries. This pilot study evaluated body image perceptions in a sample of Czech school-aged children and their parents and compared them with the perceptions of American children and parents. Ninety-seven Czech and 45 American 4th-6th graders and their parents from eight urban schools participated in this study. A previously developed silhouette body image instrument was utilized in a parent questionnaire and during child interviews to measure perceived and ideal body image perceptions of children and parents. Descriptive statistics, independent t-tests and paired t-tests were used to compare differences between children's and parents' perceived and ideal body image perceptions. Associations between body image perceptions and other variables were explored using bivariate correlations. American children had a thinner ideal body image compared with Czech children (P < 0.05). However, a larger proportion of Czech boys desired to be thinner compared with American boys (34.2% vs. 20%). Parent's ideal body image for their children did not differ by nationality (P = 0.858). While the pressure on children to look thinner was apparent among both American and Czech children, Czech children considered a larger body size as more ideal. A future study should evaluate body image perceptions and factors influencing these perceptions in a representative sample of Czech children and parents.

Body size perceptions among Pakistani women in Norway participating in a controlled trial to prevent deterioration of glucose tolerance.

PubMed

Hussain, Aysha; Bjørge, Benedikte; Hjellset, Victoria T; Holmboe-Ottesen, Gerd; Wandel, Margareta

2010-06-01

South Asians are prone to diabetes type 2 and cardiovascular diseases, which can be prevented by a diet leading to weight reduction. Body size perceptions may influence compliance to dietary advice. The objective was to study body size perceptions among Pakistani immigrant women in Norway, enrolled in a controlled trial to prevent deterioration of glucose tolerance by focussing on diet and physical activity. Participants (n=198) were 25-62 years of age, 79.8% had BMI > 25 and mean BMI was 29.6. Data were collected by questionnaire interviews with Punjabi/Urdu speaking interviewers, and body weight and height were measured. This article is based on baseline data. Stunkard's Figure Rating Scale was used. The scale consists of nine figures, representing women with different body shapes, from very thin (1-2) to very obese (6-9). The women were asked which body size they thought would connote health and wealth. A significantly smaller body size was related to health (mean 2.9) than to wealth (mean 3.3), p<0.01, and both were smaller than their self-rated own body size (mean 5.7), p<0.01. The women perceived that Pakistanis in Norway prefer women to have a smaller body size (mean 3.4) than people in Pakistan (mean 4.5), but larger than Norwegians (mean 2.5). A discrepancy score was calculated between self-rated own body size and perceived body size preference among Pakistanis in Norway. BMI was positively associated, and level of education negatively associated, with the discrepancy score. The women related body size numbers to BMI similarly to what has been described for US women. In conclusion, body size preferences among Pakistani women in this study were within the range of normal weight. However, there was a large discrepancy between own self-rated body size and the perceived ideal for Pakistanis in Norway.

Impact of condensed tannin size as individual and mixed polymers on bovine serum albumin precipitation.

PubMed

Harbertson, James F; Kilmister, Rachel L; Kelm, Mark A; Downey, Mark O

2014-10-01

Condensed tannins composed of epicatechin from monomer to octamer were isolated from cacao (Theobroma cacao, L.) seeds and added to bovine serum albumin (BSA) individually and combined as mixtures. When added to excess BSA the amount of tannin precipitated increased with tannin size. The amount of tannin required to precipitate BSA varied among the polymers with the trimer requiring the most to precipitate BSA (1000 μg) and octamer the least (50 μg). The efficacy of condensed tannins for protein precipitation increased with increased degree of polymerisation (or size) from trimers to octamers (monomers and dimers did not precipitate BSA), while mixtures of two sizes primarily had an additive effect. This study demonstrates that astringent perception is likely to increase with increasing polymer size. Further research to expand our understanding of astringent perception and its correlation with protein precipitation would benefit from sensory analysis of condensed tannins across a range of polymer sizes. Copyright © 2014 Elsevier Ltd. All rights reserved.

Music training improves pitch perception in prelingually deafened children with cochlear implants.

PubMed

Chen, Joshua Kuang-Chao; Chuang, Ann Yi Chiun; McMahon, Catherine; Hsieh, Jen-Chuen; Tung, Tao-Hsin; Li, Lieber Po-Hung

2010-04-01

The comparatively poor music appreciation in patients with cochlear implants might be ascribed to an inadequate exposure to music; however, the effect of training on music perception in prelingually deafened children with cochlear implants remains unknown. This study aimed to investigate whether previous musical education improves pitch perception ability in these children. Twenty-seven children with congenital/prelingual deafness of profound degree were studied. Test stimuli consisted of 2 sequential piano tones, ranging from C (256 Hz) to B (495 Hz). Children were asked to identify the pitch relationship between the 2 tones (same, higher, or lower). Effects of musical training duration, pitch-interval size, current age, age of implantation, gender, and type of cochlear implant on accuracy of pitch perception were evaluated. The duration of musical training positively correlated with the correct rate of pitch perception. Pitch perception performance was better in children who had a cochlear implant and were older than 6 years than in those who were aged < or =6 years (ie, preschool). Effect of pitch-interval size was insignificant on pitch perception, and there was no correlation between pitch perception and the age of implantation, gender, or type of cochlear implant. Musical training seems to improve pitch perception ability in prelingually deafened children with a cochlear implant. Auditory plasticity might play an important role in such enhancement. This suggests that incorporation of a structured training program on music perception early in life and as part of the postoperative rehabilitation program for prelingually deafened children with cochlear implants would be beneficial. A longitudinal study is needed to show whether improvement of music performance in these children is measurable by use of auditory evoked potentials.

Surviving the Worst, Expecting the Best: Teacher Perceptions of Work Life in Virginia Schools.

ERIC Educational Resources Information Center

Appalachia Educational Lab., Charleston, WV.

The qualitative study described in this document presents Virginia teachers' perceptions on 10 factors that influence their work environment: resources/instructional materials; physical facilities/class size; professional development; teacher-teacher interactions; teacher-administrator interactions; teacher-student interactions;…

Measuring the effect of attention on simple visual search.

PubMed

Palmer, J; Ames, C T; Lindsey, D T

1993-02-01

Set-size in visual search may be due to 1 or more of 3 factors: sensory processes such as lateral masking between stimuli, attentional processes limiting the perception of individual stimuli, or attentional processes affecting the decision rules for combining information from multiple stimuli. These possibilities were evaluated in tasks such as searching for a longer line among shorter lines. To evaluate sensory contributions, display set-size effects were compared with cuing conditions that held sensory phenomena constant. Similar effects for the display and cue manipulations suggested that sensory processes contributed little under the conditions of this experiment. To evaluate the contribution of decision processes, the set-size effects were modeled with signal detection theory. In these models, a decision effect alone was sufficient to predict the set-size effects without any attentional limitation due to perception.

The impact of cigarette pack shape, size and opening: evidence from tobacco company documents.

PubMed

Kotnowski, Kathy; Hammond, David

2013-09-01

To use tobacco industry documents on cigarette pack shape, size and openings to identify industry findings on associations with brand imagery, product attributes, consumer perceptions and behaviour. Internal tobacco industry research and marketing documents obtained through court disclosure contained in the Legacy Tobacco Documents Library were searched using keywords related to pack shapes, sizes and opening methods. The search identified 66 documents related to consumer research and marketing plans on pack shape, size and openings, drawn from 1973 to 2002. Industry research consistently found that packs that deviated from the traditional flip-top box projected impressions of 'modern', 'elegant' and 'unique' brand imagery. Alternative pack shape and openings were identified as an effective means to communicate product attributes, particularly with regard to premium quality and smooth taste. Consumer studies consistently found that pack shape, size and opening style influenced perceptions of reduced product harm, and were often used to communicate a 'lighter' product. Slim, rounded, oval and booklet packs were found to be particularly appealing among young adults, and several studies demonstrated increased purchase interest for tobacco products presented in novel packaging shape or opening. Evidence from consumer tracking reports and company presentations indicate that pack innovations in shape or opening method increased market share of brands. Consumer research by the tobacco industry between 1973 and 2002 found that variations in packaging shape, size and opening method could influence brand appeal and risk perceptions and increase cigarette sales. © 2013 Society for the Study of Addiction.

Effects of exposure to bodies of different sizes on perception of and satisfaction with own body size: two randomized studies.

PubMed

Bould, Helen; Carnegie, Rebecca; Allward, Heather; Bacon, Emily; Lambe, Emily; Sapseid, Megan; Button, Katherine S; Lewis, Glyn; Skinner, Andy; Broome, Matthew R; Park, Rebecca; Harmer, Catherine J; Penton-Voak, Ian S; Munafò, Marcus R

2018-05-01

Body dissatisfaction is prevalent among women and associated with subsequent obesity and eating disorders. Exposure to images of bodies of different sizes has been suggested to change the perception of 'normal' body size in others. We tested whether exposure to different-sized (otherwise identical) bodies changes perception of own and others' body size, satisfaction with body size and amount of chocolate consumed. In Study 1, 90 18-25-year-old women with normal BMI were randomized into one of three groups to complete a 15 min two-back task using photographs of women either of 'normal weight' (Body Mass Index (BMI) 22-23 kg m -2 ), or altered to appear either under- or over-weight. Study 2 was identical except the 96 participants had high baseline body dissatisfaction and were followed up after 24 h. We also conducted a mega-analysis combining both studies. Participants rated size of others' bodies, own size, and satisfaction with size pre- and post-task. Post-task ratings were compared between groups, adjusting for pre-task ratings. Participants exposed to over- or normal-weight images subsequently perceived others' bodies as smaller, in comparison to those shown underweight bodies ( p  < 0.001). They also perceived their own bodies as smaller (Study 1, p  = 0.073; Study 2, p  = 0.018; mega-analysis, p  = 0.001), and felt more satisfied with their size (Study 1, p  = 0.046; Study 2, p  = 0.004; mega-analysis, p  = 0.006). There were no differences in chocolate consumption. This study suggests that a move towards using images of women with a BMI in the healthy range in the media may help to reduce body dissatisfaction, and the associated risk of eating disorders.

Effects of exposure to bodies of different sizes on perception of and satisfaction with own body size: two randomized studies

PubMed Central

Carnegie, Rebecca; Allward, Heather; Bacon, Emily; Lambe, Emily; Sapseid, Megan; Button, Katherine S.; Lewis, Glyn; Skinner, Andy; Broome, Matthew R.; Park, Rebecca; Penton-Voak, Ian S.

2018-01-01

Body dissatisfaction is prevalent among women and associated with subsequent obesity and eating disorders. Exposure to images of bodies of different sizes has been suggested to change the perception of ‘normal’ body size in others. We tested whether exposure to different-sized (otherwise identical) bodies changes perception of own and others' body size, satisfaction with body size and amount of chocolate consumed. In Study 1, 90 18–25-year-old women with normal BMI were randomized into one of three groups to complete a 15 min two-back task using photographs of women either of ‘normal weight’ (Body Mass Index (BMI) 22–23 kg m−2), or altered to appear either under- or over-weight. Study 2 was identical except the 96 participants had high baseline body dissatisfaction and were followed up after 24 h. We also conducted a mega-analysis combining both studies. Participants rated size of others' bodies, own size, and satisfaction with size pre- and post-task. Post-task ratings were compared between groups, adjusting for pre-task ratings. Participants exposed to over- or normal-weight images subsequently perceived others' bodies as smaller, in comparison to those shown underweight bodies (p < 0.001). They also perceived their own bodies as smaller (Study 1, p = 0.073; Study 2, p = 0.018; mega-analysis, p = 0.001), and felt more satisfied with their size (Study 1, p = 0.046; Study 2, p = 0.004; mega-analysis, p = 0.006). There were no differences in chocolate consumption. This study suggests that a move towards using images of women with a BMI in the healthy range in the media may help to reduce body dissatisfaction, and the associated risk of eating disorders. PMID:29892352

Visual coding of human bodies: perceptual aftereffects reveal norm-based, opponent coding of body identity.

PubMed

Rhodes, Gillian; Jeffery, Linda; Boeing, Alexandra; Calder, Andrew J

2013-04-01

Despite the discovery of body-selective neural areas in occipitotemporal cortex, little is known about how bodies are visually coded. We used perceptual adaptation to determine how body identity is coded. Brief exposure to a body (e.g., anti-Rose) biased perception toward an identity with opposite properties (Rose). Moreover, the size of this aftereffect increased with adaptor extremity, as predicted by norm-based, opponent coding of body identity. A size change between adapt and test bodies minimized the effects of low-level, retinotopic adaptation. These results demonstrate that body identity, like face identity, is opponent coded in higher-level vision. More generally, they show that a norm-based multidimensional framework, which is well established for face perception, may provide a powerful framework for understanding body perception.

Alcohol Warning Label Perceptions: Do Warning Sizes and Plain Packaging Matter?

PubMed

Al-Hamdani, Mohammed; Smith, Steven M

2017-01-01

There is a dearth of research on the effectiveness of stringent alcohol warning labels. Our experiment tested whether increasing the size of an alcohol health warning lowers product-based ratings. We examined whether plain packaging lowers ratings of alcohol products and the consumers who use them, increases ratings of bottle "boringness," and enhances warning recognition compared with branded packaging. A total of 440 adults (51.7% female) viewed one of three warning sizes (50%, 75%, or 90% of label surface) on either a plain or branded bottle of distilled spirits, wine, and beer. Participants also rated alcohol bottles on product-based (assessing the product itself), consumer-based (assessing perceptions of consumers of the product), and bottle boringness ratings, and then attempted to recognize the correct warning out of four choices. As expected, the size of warning labels lowered product-based ratings. Similarly, plain packaging lowered product-based and consumer-based ratings and increased bottle boringness but only for wine bottles. Further, plain packaging increased the odds of warning recognition on bottles of distilled spirits. This study shows that plain packaging and warning size (similar to the graphic warnings on cigarette packages) affect perceptions about alcohol bottles. It also shows that plain packaging increases the likelihood for correct health warning recognition, which builds the case for alcohol warning and packaging research and policy.

Toward Establishing Continuity in Linguistic Skills within Early Infancy

ERIC Educational Resources Information Center

Seidl, Amanda; French, Brian; Wang, Yuanyuan; Cristia, Alejandrina

2014-01-01

A growing research line documents significant bivariate correlations between individual measures of speech perception gathered in infancy and concurrent or later vocabulary size. One interpretation of this correlation is that it reflects language specificity: Both speech perception tasks and the development of the vocabulary recruit the…

Wilderness Campers' Perception and Evaluation of Campsite Impacts.

ERIC Educational Resources Information Center

Farrell, Tracy; Hall, Troy E.; White, Dave D.

2001-01-01

Interviewed campers regarding their perceptions of impacts to vegetation, soil, and trees, comparing campers' measurements of vegetation loss, mineral soil exposure, tree damage, and site size with managers' evaluations. Most campers noticed vegetation impacts, and about half noticed soil impacts and tree damage. Most commented positively about…

Perception toward Organizational Learning Culture in Small-Size Business Enterprises

ERIC Educational Resources Information Center

Graham, Carroll M.; Nafukho, Fredrick M.

2007-01-01

This study sought to determine the relationship between four independent variables educational level, longevity, gender, type of enterprise, and the dependent variable respondents' perception of culture toward organizational learning readiness. An exploratory correlational research design was employed to survey 498 employees in seven small…

The visual perception of spatial extent.

DOT National Transportation Integrated Search

1963-09-01

This study was concerned with the manner in which perceived depth and perceived frontoparallel size varied with physical distance and hence with each other. An equation expressing the relation between perceived frontoparallel size and physical depth ...

Walking drawings and walking ability in children with cerebral palsy.

PubMed

Chong, Jimmy; Mackey, Anna H; Stott, N Susan; Broadbent, Elizabeth

2013-06-01

To investigate whether drawings of the self walking by children with cerebral palsy (CP) were associated with walking ability and illness perceptions. This was an exploratory study in 52 children with CP (M:F = 28:24), mean age 11.1 years (range 5-18), who were attending tertiary level outpatient clinics. Children were asked to draw a picture of themselves walking. Drawing size and content was used to investigate associations with clinical walk tests and children's own perceptions of their CP assessed using a CP version of the Brief Illness Perception Questionnaire. Larger drawings of the self were associated with less distance traveled, higher emotional responses to CP, and lower perceptions of pain or discomfort, independent of age. A larger self-to-overall drawing height ratio was related to walking less distance. Drawings of the self confined within buildings and the absence of other figures were also associated with reduced walking ability. Drawing size and content can reflect walking ability, as well as symptom perceptions and distress. Drawings may be useful for clinicians to use with children with cerebral palsy to aid discussion about their condition. PsycINFO Database Record (c) 2013 APA, all rights reserved.

The Motivational Climate and Intrinsic Motivation in the Rehabilitation Setting.

PubMed

Brinkman-Majewski, Rachel E; Weiss, Windee M

2018-02-06

The motivational climate created by the athletic trainer in rehabilitation may be critical in influencing athletes' intrinsic motivation and other psychosocial outcomes in the rehabilitation and the recovery process. The purpose of this study was to examine intercollegiate athletes' perceptions of the motivational climate in the rehabilitation setting. Specifically, examining if perceptions of the motivational climate can predict athletes' levels of intrinsic motivation with rehabilitation as well as the relationship between perceptions of the motivational climate and athlete demographics (gender, starter status, athletic trainer gender, etc). Cross-sectional, descriptive research. College sport team and athletic training center. NCAA Division II intercollegiate athletes from one institution (n = 187; 125 male, 62 female). Paper-based survey measuring: mastery and performance perceptions of the motivational climate in rehabilitation, athletes' goal orientation in sport, athletes' levels of motivation in rehabilitation. Perceptions of a performance climate was positively related to intrinsic motivation effort-improvement (effect size=25.34%). Perceptions of a mastery climate were positively related to interest-enjoyment and perceived competence and negatively related to tension-pressure (effect size=39.03%). In general, female athletes, as well as athletes with a female athletic trainer, had significantly higher perceptions of mastery motivational climate effort-improvement compared to male athletes and athletes with male athletic trainers. While male athletes and athletes with male athletic trainers had higher perceptions of intra-team member rivalry in rehabilitation. The athlete's gender and goal orientation, as well as the gender of the athletic trainer creating the motivational climate, can influence whether the environment is perceived as more mastery or performance. The recovering athletes' perceptions of the climate in rehabilitation can, in turn, affect their intrinsic motivation toward the therapeutic interventions.

The predictors of chemistry achievement of 12th grade students in secondary schools in the United Arab Emirates

NASA Astrophysics Data System (ADS)

Khalaf, Ali Khalfan

2000-10-01

The purpose of this study is to explore variables related to chemistry achievement of 12th grade science students in the United Arab Emirates (UAE). The focus is to identify student, teacher, and school variables that predict chemistry achievement. The analysis sample included 204 males and 252 females in 66 classes in 60 schools from 10 districts or bureaus of education in the UAE. Thirty-two male and 33 female chemistry teachers and 60 school principals were included. The Khalaf Chemistry Achievement Test, GALT, the Student Questionnaire, Teacher Questionnaire, and School Information Questionnaire were administered. Descriptive statistics, correlations, analyses of variance, factor analysis, and stepwise multiple linear regression analyses were done. The results indicate that demographic, home environment, prior knowledge, scholastic ability, attitudes and perceptions related to chemistry and science, and student perception of instructional practices variables correlated with student chemistry achievement. The amount of help teachers received from the supervisor, class size, and courses in geology were teacher variables that correlated with class chemistry achievement. Nine school variables involving school, division, and class sizes correlated with school chemistry achievement. Analyses of variance revealed significant interaction effects: district by school size and district by student gender. In two districts, students in small schools achieved better than those in large schools. Generally female students achieved equal to or better than males. Three factors from the factor analysis: School Size, Prior Student Achievement, and Student Perception of Teacher Effectiveness, correlated with school chemistry achievement. The results of the multiple linear regression indicated that the factors of Prior Student Achievement, Student Perception of Teacher Effectiveness, and Teacher Experience and Expertise accounted for 45% of the variance in school chemistry achievement. Results indicate that the strongest predictors of chemistry achievement are prior achievement in science, Arabic language, and mathematics; student perception of teacher effectiveness; and teacher experience and expertise. Females tend to achieve better in chemistry than males. No nationality differences were found and the relationship of school size to chemistry achievement was inconclusive. Recommendations related to chemistry and science are presented. These include curriculum, school practice, teacher professional development, and future research.

Investigating Young Children's Perceptions of Body Size and Healthy Habits

ERIC Educational Resources Information Center

Xu, Tingting; Nerren, Jannah S.

2017-01-01

Attitudes and biases toward body size perceived as fat and body size perceived as thin are present in young children (Cramer and Steinwert in "J Appl Dev Psychol" 19(3):429-451, 1998; Worobey and Worobey in "Body Image" 11:171-174, 2014). However, the information children have regarding body size and ways to modify body size…

Embodied experiences for science learning: A cognitive linguistics exploration of middle school students' language in learning about water

NASA Astrophysics Data System (ADS)

Salinas Barrios, Ivan Eduardo

I investigated linguistic patterns in middle school students' writing to understand their relevant embodied experiences for learning science. Embodied experiences are those limited by the perceptual and motor constraints of the human body. Recent research indicates student understanding of science needs embodied experiences. Recent emphases of science education researchers in the practices of science suggest that students' understanding of systems and their structure, scale, size, representations, and causality are crosscutting concepts that unify all scientific disciplinary areas. To discern the relationship between linguistic patterns and embodied experiences, I relied on Cognitive Linguistics, a field within cognitive sciences that pays attention to language organization and use assuming that language reflects the human cognitive system. Particularly, I investigated the embodied experiences that 268 middle school students learning about water brought to understanding: i) systems and system structure; ii) scale, size and representations; and iii) causality. Using content analysis, I explored students' language in search of patterns regarding linguistic phenomena described within cognitive linguistics: image schemas, conceptual metaphors, event schemas, semantical roles, and force-dynamics. I found several common embodied experiences organizing students' understanding of crosscutting concepts. Perception of boundaries and change in location and perception of spatial organization in the vertical axis are relevant embodied experiences for students' understanding of systems and system structure. Direct object manipulation and perception of size with and without locomotion are relevant for understanding scale, size and representations. Direct applications of force and consequential perception of movement or change in form are relevant for understanding of causality. I discuss implications of these findings for research and science teaching.

Poor shape perception is the reason reaches-to-grasp are visually guided online.

PubMed

Lee, Young-Lim; Crabtree, Charles E; Norman, J Farley; Bingham, Geoffrey P

2008-08-01

Both judgment studies and studies of feedforward reaching have shown that the visual perception of object distance, size, and shape are inaccurate. However, feedback has been shown to calibrate feedfoward reaches-to-grasp to make them accurate with respect to object distance and size. We now investigate whether shape perception (in particular, the aspect ratio of object depth to width) can be calibrated in the context of reaches-to-grasp. We used cylindrical objects with elliptical cross-sections of varying eccentricity. Our participants reached to grasp the width or the depth of these objects with the index finger and thumb. The maximum grasp aperture and the terminal grasp aperture were used to evaluate perception. Both occur before the hand has contacted an object. In Experiments 1 and 2, we investigated whether perceived shape is recalibrated by distorted haptic feedback. Although somewhat equivocal, the results suggest that it is not. In Experiment 3, we tested the accuracy of feedforward grasping with respect to shape with haptic feedback to allow calibration. Grasping was inaccurate in ways comparable to findings in shape perception judgment studies. In Experiment 4, we hypothesized that online guidance is needed for accurate grasping. Participants reached to grasp either with or without vision of the hand. The result was that the former was accurate, whereas the latter was not. We conclude that shape perception is not calibrated by feedback from reaches-to-grasp and that online visual guidance is required for accurate grasping because shape perception is poor.

Gender Differences within Perceptions of Virtual Communities

ERIC Educational Resources Information Center

Harper, Vernon, Jr.

2007-01-01

Virtual communities are quickly becoming the standard mode of interaction in educational and professional contexts. However, the literature fails to accurately address the possibility of differences in the perceptions of these communities related to sex. Two-hundred and twenty-six students from a medium-sized university in the Mid-Atlantic United…

“What Women Like”: Influence of Motion and Form on Esthetic Body Perception

PubMed Central

Cazzato, Valentina; Siega, Serena; Urgesi, Cosimo

2012-01-01

Several studies have shown the distinct contribution of motion and form to the esthetic evaluation of female bodies. Here, we investigated how variations of implied motion and body size interact in the esthetic evaluation of female and male bodies in a sample of young healthy women. Participants provided attractiveness, beauty, and liking ratings for the shape and posture of virtual renderings of human bodies with variable body size and implied motion. The esthetic judgments for both shape and posture of human models were influenced by body size and implied motion, with a preference for thinner and more dynamic stimuli. Implied motion, however, attenuated the impact of extreme body size on the esthetic evaluation of body postures, while body size variations did not affect the preference for more dynamic stimuli. Results show that body form and action cues interact in esthetic perception, but the final esthetic appreciation of human bodies is predicted by a mixture of perceptual and affective evaluative components. PMID:22866044

The influence of maturation, body size and physical self-perceptions on longitudinal changes in physical activity in adolescent girls.

PubMed

Fawkner, Samantha; Henretty, Joan; Knowles, Ann-Marie; Nevill, Alan; Niven, Ailsa

2014-01-01

The aim of this study was to adopt a longitudinal design to explore the direct effects of both absolute and relative maturation and changes in body size on physical activity, and explore if, and how, physical self-perceptions might mediate this effect. We recruited 208 girls (11.8 ± 0.4 years) at baseline. Data were collected at three subsequent time points, each 6 months apart. At 18 months, 119 girls remained in the study. At each time point, girls completed the Physical Activity Questionnaire for Children, the Pubertal Development Scale (from which, both a measure of relative and absolute maturation were defined) and the Physical Self-Perception Profile, and had physical size characteristics assessed. Multilevel modelling for physical activity indicated a significant negative effect of age, positive effect for physical condition and sport competence and positive association for relatively early maturers. Absolute maturation, body mass, waist circumference and sum of skinfolds did not significantly contribute to the model. Contrary to common hypotheses, relatively more mature girls may, in fact, be more active than their less mature peers. However, neither changes in absolute maturation nor physical size appear to directly influence changes in physical activity in adolescent girls.

Adolescent girls and young adult women's perceptions of superslims cigarette packaging: a qualitative study

PubMed Central

Ford, Allison; Moodie, Crawford; Purves, Richard; MacKintosh, Anne Marie

2016-01-01

Objectives To explore perceptions of superslims packaging, including compact ‘lipstick’ packs, in line with 3 potential impacts identified within the impact assessment of the European Union (EU) Tobacco Products Directive: appeal, harm perceptions and the seriousness of warning of health risks. Design Qualitative focus group study. Setting Informal community venues in Scotland, UK. Participants 75 female non-smokers and occasional smokers (age range 12–24). Results Compact ‘lipstick’-type superslims packs were perceived most positively and rated as most appealing. They were also viewed as less harmful than more standard sized cigarette packs because of their smaller size and likeness to cosmetics. Additionally, ‘lipstick’ packs were rated as less serious in terms of warning about the health risks associated with smoking, either because the small font size of the warnings was difficult to read or because the small pack size prevented the text on the warnings from being displayed properly. Bright pack colours and floral designs were also thought to detract from the health warning. Conclusions As superslims packs were found to increase appeal, mislead with respect to level of harm, and undermine the on-pack health warnings, this provides support for the decision to ban ‘lipstick’-style cigarette packs in the EU and has implications for policy elsewhere. PMID:26747040

Parietal cortex mediates perceptual Gestalt grouping independent of stimulus size.

PubMed

Grassi, Pablo R; Zaretskaya, Natalia; Bartels, Andreas

2016-06-01

The integration of local moving elements into a unified gestalt percept has previously been linked to the posterior parietal cortex. There are two possible interpretations for the lack of involvement of other occipital regions. The first is that parietal cortex is indeed uniquely functionally specialized to perform grouping. Another possibility is that other visual regions can perform grouping as well, but that the large spatial separation of the local elements used previously exceeded their neurons' receptive field (RF) sizes, preventing their involvement. In this study we distinguished between these two alternatives. We measured whole-brain activity using fMRI in response to a bistable motion illusion that induced mutually exclusive percepts of either an illusory global Gestalt or of local elements. The stimulus was presented in two sizes, a large version known to activate IPS only, and a version sufficiently small to fit into the RFs of mid-level dorsal regions such as V5/MT. We found that none of the separately localized motion regions apart from parietal cortex showed a preference for global Gestalt perception, even for the smaller version of the stimulus. This outcome suggests that grouping-by-motion is mediated by a specialized size-invariant mechanism with parietal cortex as its anatomical substrate. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of Class Size and Attendance Policy on University Classroom Interaction in Taiwan

ERIC Educational Resources Information Center

Bai, Yin; Chang, Te-Sheng

2016-01-01

Classroom interaction experience is one of the main parts of students' learning lives. However, surprisingly little research has investigated students' perceptions of classroom interaction with different attendance policies across different class sizes in the higher education system. To elucidate the effects of class size and attendance policy on…

Chemical Affinity between Tannin Size and Salivary Protein Binding Abilities: Implications for Wine Astringency

PubMed Central

Ma, Wen; Waffo-Teguo, Pierre; Jourdes, Michael; Li, Hua

2016-01-01

Astringency perception, as an essential parameter for high-quality red wine, is principally elicited by condensed tannins in diversified chemical structures. Condensed tannins, which are also known as proanthocyanidins (PAs), belong to the flavonoid class of polyphenols and are incorporated by multiple flavan-3-ols units according to their degree of polymerization (DP). However, the influence of DP size of PAs on astringency perception remains unclear for decades. This controversy was mainly attributed to the lack of efficient strategies to isolate the PAs in non-galloylated forms and with individual degree size from grape/wine. In the present study, the astringency intensity of purified and identified grape oligomeric tannins (DP ranged from 1 to 5) was firstly explored. A novel non-solid phase strategy was used to rapidly exclude the galloylated PAs from the non-galloylated PAs and fractionate the latter according to their DP size. Then, a series of PAs with individual DP size and galloylation were purified by an approach of preparative hydrophilic interaction chromatography. Furthermore, purified compounds were identified by both normal phase HPLC-FLD and reverse phase UHPLC-ESI-Q-TOF. Finally, the contribution of the astringency perception of the individual purified tannins was examined with a salivary protein binding ability test. The results were observed by HPLC-FLD and quantified by changes in PA concentration remaining in the filtrate. In summary, a new approach without a solid stationary phase was developed to isolate PAs according to their DP size. And a positive relationship between the DP of PAs and salivary protein affinity was revealed. PMID:27518822

Chemical Affinity between Tannin Size and Salivary Protein Binding Abilities: Implications for Wine Astringency.

PubMed

Ma, Wen; Waffo-Teguo, Pierre; Jourdes, Michael; Li, Hua; Teissedre, Pierre-Louis

2016-01-01

Astringency perception, as an essential parameter for high-quality red wine, is principally elicited by condensed tannins in diversified chemical structures. Condensed tannins, which are also known as proanthocyanidins (PAs), belong to the flavonoid class of polyphenols and are incorporated by multiple flavan-3-ols units according to their degree of polymerization (DP). However, the influence of DP size of PAs on astringency perception remains unclear for decades. This controversy was mainly attributed to the lack of efficient strategies to isolate the PAs in non-galloylated forms and with individual degree size from grape/wine. In the present study, the astringency intensity of purified and identified grape oligomeric tannins (DP ranged from 1 to 5) was firstly explored. A novel non-solid phase strategy was used to rapidly exclude the galloylated PAs from the non-galloylated PAs and fractionate the latter according to their DP size. Then, a series of PAs with individual DP size and galloylation were purified by an approach of preparative hydrophilic interaction chromatography. Furthermore, purified compounds were identified by both normal phase HPLC-FLD and reverse phase UHPLC-ESI-Q-TOF. Finally, the contribution of the astringency perception of the individual purified tannins was examined with a salivary protein binding ability test. The results were observed by HPLC-FLD and quantified by changes in PA concentration remaining in the filtrate. In summary, a new approach without a solid stationary phase was developed to isolate PAs according to their DP size. And a positive relationship between the DP of PAs and salivary protein affinity was revealed.

Effects of electrode size and spacing on sensory modalities in the phantom thumb perception area for the forearm amputees.

PubMed

Li, P; Chai, G H; Zhu, K H; Lan, N; Sui, X H

2015-01-01

Tactile sensory feedback plays a key role in accomplishing the dexterous manipulation of prosthetic hands for the amputees, and the non-invasive transcutaneous electrical nerve stimulation (TENS) of the phantom finger perception (PFP) area would be an effective way to realize sensory feedback clinically. In order to realize the high-spatial-resolution tactile sensory feedback in the PFP region, we investigated the effects of electrode size and spacing on the tactile sensations for potentially optimizing the surface electrode array configuration. Six forearm-amputated subjects were recruited in the psychophysical studies. With the diameter of the circular electrode increasing from 3 mm to 12 mm, the threshold current intensity was enhanced correspondingly under different sensory modalities. The smaller electrode could potentially lead to high sensation spatial resolution. Whereas, the smaller the electrode, the less the number of sensory modalities. For an Φ-3 mm electrode, it is even hard for the subject to perceive any perception modalities under normal stimulating current. In addition, the two-electrode discrimination distance (TEDD) in the phantom thumb perception area decreased with electrode size decreasing in two directions of parallel or perpendicular to the forearm. No significant difference of TEDD existed along the two directions. Studies in this paper would guide the configuration optimization of the TENS electrode array for potential high spatial-resolution sensory feedback.

Correlation Between Measured Noise And Its Visual Perception.

NASA Astrophysics Data System (ADS)

Bollen, Romain

1986-06-01

For obvious reasons people in the field claim that measured data do not agree with what they perceive. Scientists reply by saying that their data are "true". Are they? Since images are made to be looked at, a request for data meaningful for what is perceived, is not foolish. We show that, when noise is characterized by standard density fluctuation figures, a good correlation with noise perception by the naked eye on a large size radiograph is obtained in applying microdensitometric scanning with a 400 micron aperture. For other viewing conditions the aperture size has to be adapted.

Perception of the average size of multiple objects in chimpanzees (Pan troglodytes).

PubMed

Imura, Tomoko; Kawakami, Fumito; Shirai, Nobu; Tomonaga, Masaki

2017-08-30

Humans can extract statistical information, such as the average size of a group of objects or the general emotion of faces in a crowd without paying attention to any individual object or face. To determine whether summary perception is unique to humans, we investigated the evolutional origins of this ability by assessing whether chimpanzees, which are closely related to humans, can also determine the average size of multiple visual objects. Five chimpanzees and 18 humans were able to choose the array in which the average size was larger, when presented with a pair of arrays, each containing 12 circles of different or the same sizes. Furthermore, both species were more accurate in judging the average size of arrays consisting of 12 circles of different or the same sizes than they were in judging the average size of arrays consisting of a single circle. Our findings could not be explained by the use of a strategy in which the chimpanzee detected the largest or smallest circle among those in the array. Our study provides the first evidence that chimpanzees can perceive the average size of multiple visual objects. This indicates that the ability to compute the statistical properties of a complex visual scene is not unique to humans, but is shared between both species. © 2017 The Authors.

Perception of the average size of multiple objects in chimpanzees (Pan troglodytes)

PubMed Central

Kawakami, Fumito; Shirai, Nobu; Tomonaga, Masaki

2017-01-01

Humans can extract statistical information, such as the average size of a group of objects or the general emotion of faces in a crowd without paying attention to any individual object or face. To determine whether summary perception is unique to humans, we investigated the evolutional origins of this ability by assessing whether chimpanzees, which are closely related to humans, can also determine the average size of multiple visual objects. Five chimpanzees and 18 humans were able to choose the array in which the average size was larger, when presented with a pair of arrays, each containing 12 circles of different or the same sizes. Furthermore, both species were more accurate in judging the average size of arrays consisting of 12 circles of different or the same sizes than they were in judging the average size of arrays consisting of a single circle. Our findings could not be explained by the use of a strategy in which the chimpanzee detected the largest or smallest circle among those in the array. Our study provides the first evidence that chimpanzees can perceive the average size of multiple visual objects. This indicates that the ability to compute the statistical properties of a complex visual scene is not unique to humans, but is shared between both species. PMID:28835550

Medical Student Perceptions of the Learning Environment in Medical School Change as Students Transition to Clinical Training in Undergraduate Medical School.

PubMed

Dunham, Lisette; Dekhtyar, Michael; Gruener, Gregory; CichoskiKelly, Eileen; Deitz, Jennifer; Elliott, Donna; Stuber, Margaret L; Skochelak, Susan E

2017-01-01

Phenomenon: The learning environment is the physical, social, and psychological context in which a student learns. A supportive learning environment contributes to student well-being and enhances student empathy, professionalism, and academic success, whereas an unsupportive learning environment may lead to burnout, exhaustion, and cynicism. Student perceptions of the medical school learning environment may change over time and be associated with students' year of training and may differ significantly depending on the student's gender or race/ethnicity. Understanding the changes in perceptions of the learning environment related to student characteristics and year of training could inform interventions that facilitate positive experiences in undergraduate medical education. The Medical School Learning Environment Survey (MSLES) was administered to 4,262 students who matriculated at one of 23 U.S. and Canadian medical schools in 2010 and 2011. Students completed the survey at the end of each year of medical school as part of a battery of surveys in the Learning Environment Study. A mixed-effects longitudinal model, t tests, Cohen's d effect size, and analysis of variance assessed the relationship between MSLES score, year of training, and demographic variables. After controlling for gender, race/ethnicity, and school, students reported worsening perceptions toward the medical school learning environment, with the worst perceptions in the 3rd year of medical school as students begin their clinical experiences, and some recovery in the 4th year after Match Day. The drop in MSLES scores associated with the transition to the clinical learning environment (-0.26 point drop in addition to yearly change, effect size = 0.52, p < .0001) is more than 3 times greater than the drop between the 1st and 2nd year (0.07 points, effect size = 0.14, p < .0001). The largest declines were from items related to work-life balance and informal student relationships. There was some, but not complete, recovery in perceptions of the medical school learning environment in the 4th year. Insights: Perceptions of the medical school learning environment worsen as students continue through medical school, with a stronger decline in perception scores as students' transition to the clinical learning environment. Students reported the greatest drop in finding time for outside activities and students helping one another in the 3rd year. Perceptions differed based on gender and race/ethnicity. Future studies should investigate the specific features of medical schools that contribute most significantly to student perceptions of the medical school learning environment, both positive and negative, to pinpoint potential interventions and improvements.

Perception of speaker size and sex of vowel sounds

NASA Astrophysics Data System (ADS)

Smith, David R. R.; Patterson, Roy D.

2005-04-01

Glottal-pulse rate (GPR) and vocal-tract length (VTL) are both related to speaker size and sex-however, it is unclear how they interact to determine our perception of speaker size and sex. Experiments were designed to measure the relative contribution of GPR and VTL to judgements of speaker size and sex. Vowels were scaled to represent people with different GPRs and VTLs, including many well beyond the normal population values. In a single interval, two response rating paradigm, listeners judged the size (using a 7-point scale) and sex/age of the speaker (man, woman, boy, or girl) of these scaled vowels. Results from the size-rating experiments show that VTL has a much greater influence upon judgements of speaker size than GPR. Results from the sex-categorization experiments show that judgements of speaker sex are influenced about equally by GPR and VTL for vowels with normal GPR and VTL values. For abnormal combinations of GPR and VTL, where low GPRs are combined with short VTLs, VTL has more influence than GPR in sex judgements. [Work supported by the UK MRC (G9901257) and the German Volkswagen Foundation (VWF 1/79 783).

Center of mass perception and inertial frames of reference.

PubMed

Bingham, G P; Muchisky, M M

1993-11-01

Center of mass perception was investigated by varying the shape, size, and orientation of planar objects. Shape was manipulated to investigate symmetries as information. The number of reflective symmetry axes, the amount of rotational symmetry, and the presence of radial symmetry were varied. Orientation affected systematic errors. Judgments tended to undershoot the center of mass. Random errors increased with size and decreased with symmetry. Size had no effect on random errors for maximally symmetric objects, although orientation did. The spatial distributions of judgments were elliptical. Distribution axes were found to align with the principle moments of inertia. Major axes tended to align with gravity in maximally symmetric objects. A functional and physical account was given in terms of the repercussions of error. Overall, judgments were very accurate.

College Students' Perceptions of Community-Oriented Policing at a Mid-Size Public University

ERIC Educational Resources Information Center

Cooper, Joseph J.

2017-01-01

Campus crime and distrust of campus police are significant problems for institutions of higher education. Utilizing the Broken Windows Theory (Kelling & Wilson, 1982) as the theoretical framework, the purpose of this qualitative study was to explore students' attitudes toward community-oriented policing and their perceptions of crime, safety,…

Ensemble Perception of Size in 4-5-Year-Old Children

ERIC Educational Resources Information Center

Sweeny, Timothy D.; Wurnitsch, Nicole; Gopnik, Alison; Whitney, David

2015-01-01

Groups of objects are nearly everywhere we look. Adults can perceive and understand the "gist" of multiple objects at once, engaging ensemble-coding mechanisms that summarize a group's overall appearance. Are these group-perception mechanisms in place early in childhood? Here, we provide the first evidence that 4-5-year-old children use…

Remote Rural Students' Perceptions of Their Collegiate Transition Experience

ERIC Educational Resources Information Center

Rains, Linda Marie Peterson

2009-01-01

This research project focused on the perceptions of students from remote rural communities as they told of their transition experiences to a mid-size, research-intensive university. During the spring of 2008, thirteen students from North Dakota remote rural counties agreed to be interviewed for this study. Ten females and three males from seven…

Basic School Teachers' Perceptions about Curriculum Design in Ghana

ERIC Educational Resources Information Center

Abudu, Amadu Musah; Mensah, Mary Afi

2016-01-01

This study focused on teachers' perceptions about curriculum design and barriers to their participation. The sample size was 130 teachers who responded to a questionnaire. The analyses made use of descriptive statistics and descriptions. The study found that the level of teachers' participation in curriculum design is low. The results further…

Cortical plasticity as a mechanism for storing Bayesian priors in sensory perception.

PubMed

Köver, Hania; Bao, Shaowen

2010-05-05

Human perception of ambiguous sensory signals is biased by prior experiences. It is not known how such prior information is encoded, retrieved and combined with sensory information by neurons. Previous authors have suggested dynamic encoding mechanisms for prior information, whereby top-down modulation of firing patterns on a trial-by-trial basis creates short-term representations of priors. Although such a mechanism may well account for perceptual bias arising in the short-term, it does not account for the often irreversible and robust changes in perception that result from long-term, developmental experience. Based on the finding that more frequently experienced stimuli gain greater representations in sensory cortices during development, we reasoned that prior information could be stored in the size of cortical sensory representations. For the case of auditory perception, we use a computational model to show that prior information about sound frequency distributions may be stored in the size of primary auditory cortex frequency representations, read-out by elevated baseline activity in all neurons and combined with sensory-evoked activity to generate a perception that conforms to Bayesian integration theory. Our results suggest an alternative neural mechanism for experience-induced long-term perceptual bias in the context of auditory perception. They make the testable prediction that the extent of such perceptual prior bias is modulated by both the degree of cortical reorganization and the magnitude of spontaneous activity in primary auditory cortex. Given that cortical over-representation of frequently experienced stimuli, as well as perceptual bias towards such stimuli is a common phenomenon across sensory modalities, our model may generalize to sensory perception, rather than being specific to auditory perception.

Development and Validation of the Body Size Scale for Assessing Body Weight Perception in African Populations

PubMed Central

Cohen, Emmanuel; Bernard, Jonathan Y.; Ponty, Amandine; Ndao, Amadou; Amougou, Norbert; Saïd-Mohamed, Rihlat; Pasquet, Patrick

2015-01-01

Background The social valorisation of overweight in African populations could promote high-risk eating behaviours and therefore become a risk factor of obesity. However, existing scales to assess body image are usually not accurate enough to allow comparative studies of body weight perception in different African populations. This study aimed to develop and validate the Body Size Scale (BSS) to estimate African body weight perception. Methods Anthropometric measures of 80 Cameroonians and 81 Senegalese were used to evaluate three criteria of adiposity: body mass index (BMI), overall percentage of fat, and endomorphy (fat component of the somatotype). To develop the BSS, the participants were photographed in full face and profile positions. Models were selected for their representativeness of the wide variability in adiposity with a progressive increase along the scale. Then, for the validation protocol, participants self-administered the BSS to assess self-perceived current body size (CBS), desired body size (DBS) and provide a “body self-satisfaction index.” This protocol included construct validity, test-retest reliability and convergent validity and was carried out with three independent samples of respectively 201, 103 and 1115 Cameroonians. Results The BSS comprises two sex-specific scales of photos of 9 models each, and ordered by increasing adiposity. Most participants were able to correctly order the BSS by increasing adiposity, using three different words to define body size. Test-retest reliability was consistent in estimating CBS, DBS and the “body self-satisfaction index.” The CBS was highly correlated to the objective BMI, and two different indexes assessed with the BSS were consistent with declarations obtained in interviews. Conclusion The BSS is the first scale with photos of real African models taken in both full face and profile and representing a wide and representative variability in adiposity. The validation protocol proved its reliability for estimating body weight perception in Africans. PMID:26536030

Dropout Rates in Texas School Districts: Influences of School Size and Ethnic Group.

ERIC Educational Resources Information Center

Toenjes, Laurence A.

Longitudinal dropout rates (LDR's) for public school students and LDR's of pupil membership by ethnic group based on two Texas Education Agency reports are estimated. LDR's are calculated for the state, by school district size, for the 21 largest districts, and by average high school size. Findings dispel the prevalent perception of the dropout…

Size Matters: The Link between Staff Size and Perceived Organizational Support in Early Childhood Education

ERIC Educational Resources Information Center

Ho, Dora; Lee, Moosung; Teng, Yue

2016-01-01

Purpose: The purpose of this paper is to examine the relationship between staff size and perceived organizational support (POS) in early childhood education (ECE) organizations. Design/methodology/approach: A territory-wide questionnaire survey was designed to investigate the perceptions of preschool teachers in Hong Kong on four dimensions of…

Size, skills, and suffrage: Motivated distortions in perceived formidability of political leaders

PubMed Central

Blaker, Nancy M.; Pollet, Thomas V.

2017-01-01

Research shows that perception of physical size and status are positively associated. The current study was developed to replicate and extend earlier research on height perceptions of political leaders, indicating that supporters perceive their leaders as taller than non-supporters do, and winners are perceived as taller after the elections, while losers are perceived as shorter after the elections (winner/loser effects). Individuals use greater height and strength as indications of greater physical formidability. We hypothesized that in-group leaders’ height and strength, but not weight, would be overestimated more compared to out-group leaders’, and that this status-size association is not only driven by dominance, but also by prestige. We also tested whether previously found gender effects in estimates were due to using one’s own height as an anchor, and we used an improved methodological approach by relying on multiple measurements of physical formidability and a within-subject design for testing winner/loser effects. The results of a two-part longitudinal study (self-selected sample via voting advice website; NWave1 = 2,011; NWave2 = 322) suggest that estimated physical formidability of political leaders is affected by motivated perception, as prestige was positively associated with estimated formidability, and in-group leaders were estimated more formidable than out-group leaders. We conclude that distortions in judged formidability related to social status are the result of motivated social perception in order to promote group functioning and leadership. Although we did not replicate a winner-effect (greater estimations of formidability after winning the elections), we did find some evidence for a loser-effect. Earlier suggestions that men make larger estimations than women because of their own larger body size are not supported. Implications for theory and future research are discussed. PMID:29267275

Liberian Educational Stakeholders' Perceptions of Overcrowding in an Urban Public Elementary School in Monrovia

ERIC Educational Resources Information Center

Dalieh, Franklin T.

2017-01-01

In post-conflict Liberia, more students are returning to schools and moving to urban areas resulting in overcrowding and class sizes that surpassed recommended and legally-sanctioned limits. The purpose of this qualitative case study was to explore educational stakeholders' perceptions of the factors (e.g., organizational leadership, social, and…

Gender, BMI, Values, and Learning in Physical Education: A Study on Chinese Middle Schoolers

ERIC Educational Resources Information Center

Ding, Haiyong; Sun, Haichun; Chen, Ang

2011-01-01

Students' different perceptions of task values influence their learning experience and achievement in physical education. Framed using the subjective task value construct, this study was conducted to determine the extent to which male and female Chinese middle schoolers with different body sizes differed in their perception of the task values. A…

Don't Look down: Emotional Arousal Elevates Height Perception

ERIC Educational Resources Information Center

Stefanucci, Jeanine K.; Storbeck, Justin

2009-01-01

In a series of experiments, it was found that emotional arousal can influence height perception. In Experiment 1, participants viewed either arousing or nonarousing images before estimating the height of a 2-story balcony and the size of a target on the ground below the balcony. People who viewed arousing images overestimated height and target…

Skills Gaps in Australian Firms

ERIC Educational Resources Information Center

Lindorff, Margaret

2011-01-01

This paper reports the results of a survey of more than 2000 managers examining perceptions of skills gaps in a range of Australian firms. It finds that three quarters report a skills gap, and almost one third report skills gaps across the whole organisation. Firm size and industry differences exist in perceptions of the effect of the skills gap…

Community College Administrators' and Local Stakeholders' Perceptions Concerning the Economic Development Strategies Used by North Carolina Community Colleges.

ERIC Educational Resources Information Center

Boone, John Bower; Gillett-Karam, Rosemary

1996-01-01

Describes a study comparing the perceptions of community college and community leaders regarding economic development strategies utilized by North Carolina community colleges. Indicates that the level of satisfaction with strategies was related to respondents' perceived level of use of strategies, position held, and institution size. (17…

Beginning High School: Christian Students' Perceptions and Choices

ERIC Educational Resources Information Center

Tengler, Ashley S.; Seifert, Lauren S.

2017-01-01

Moving from middle to high school can bring challenges for adolescents in the United States, with self-reports indicating areas that might need attention. Christian ninth grade students gave structured interviews about their perceptions of the transition. Issues like a change in the type (e.g., private to public) or size of school were discussed.…

Saturation in Phosphene Size with Increasing Current Levels Delivered to Human Visual Cortex.

PubMed

Bosking, William H; Sun, Ping; Ozker, Muge; Pei, Xiaomei; Foster, Brett L; Beauchamp, Michael S; Yoshor, Daniel

2017-07-26

Electrically stimulating early visual cortex results in a visual percept known as a phosphene. Although phosphenes can be evoked by a wide range of electrode sizes and current amplitudes, they are invariably described as small. To better understand this observation, we electrically stimulated 93 electrodes implanted in the visual cortex of 13 human subjects who reported phosphene size while stimulation current was varied. Phosphene size increased as the stimulation current was initially raised above threshold, but then rapidly reached saturation. Phosphene size also depended on the location of the stimulated site, with size increasing with distance from the foveal representation. We developed a model relating phosphene size to the amount of activated cortex and its location within the retinotopic map. First, a sigmoidal curve was used to predict the amount of activated cortex at a given current. Second, the amount of active cortex was converted to degrees of visual angle by multiplying by the inverse cortical magnification factor for that retinotopic location. This simple model accurately predicted phosphene size for a broad range of stimulation currents and cortical locations. The unexpected saturation in phosphene sizes suggests that the functional architecture of cerebral cortex may impose fundamental restrictions on the spread of artificially evoked activity and this may be an important consideration in the design of cortical prosthetic devices. SIGNIFICANCE STATEMENT Understanding the neural basis for phosphenes, the visual percepts created by electrical stimulation of visual cortex, is fundamental to the development of a visual cortical prosthetic. Our experiments in human subjects implanted with electrodes over visual cortex show that it is the activity of a large population of cells spread out across several millimeters of tissue that supports the perception of a phosphene. In addition, we describe an important feature of the production of phosphenes by electrical stimulation: phosphene size saturates at a relatively low current level. This finding implies that, with current methods, visual prosthetics will have a limited dynamic range available to control the production of spatial forms and that more advanced stimulation methods may be required. Copyright © 2017 the authors 0270-6474/17/377188-10$15.00/0.

Dietary Habits and Body Size Perception of Elementary School Children

ERIC Educational Resources Information Center

Murimi, Mary W.

2004-01-01

This study assessed the attitudes and concerns of children in grades 1 through 5 regarding their perceived body size and ideal body size, and it assessed their Body Mass Index (BMI) and dietary habits. This study found an overweight prevalence of 11.4%, based on the children's BMI. Most of the overweight students were either African American or…

Body Image Issues In Lithuanian Magazines Aimed For Children And Adolescents In Relation To Body Mass Index And Body Size Perception Of 16-19 Y. Old Girls During The Last 15 Years.

PubMed

Tutkuviene, Janina; Misiute, Agne; Strupaite, Ieva; Paulikaite, Gintare; Pavlovskaja, Erika

2017-03-01

Mass media plays an important role in forming body image and makes the significant impact on body size perception in children and adolescents. The aim of present study was to reveal trends in depiction of body image cues in Lithuanian magazines aimed for children and adolescents in relation to changes of real body mass index (BMI) and body size perception of 16-19 y. old girls in the year 2000 and the 2015. Three popular journals published both in the year 2000 and the 2015, were chosen for in-depth analysis of their contents (the periodicity of different topics was counted and compared). Attention given to a healthy body image has increased and the promotion of especially skinny females’ body has decreased during the last 15 years from the dominant type in the year 2000 to depiction of slightly thin or normal body build in the 2015. However, the real BMI of 16-19 y. old Lithuanian girls has significantly increased during the 2000-2015 period (from 20.09 till 21.32 kg/m²; p<0,001). Despite this fact, the older adolescent girls were more satisfied with their own body size and shape in the year 2015 than in the 2000. The present study showed that changing depictions of body image issues in mass media (magazines aimed for adolescent girls) were in parallel with the proper self-esteem of body size in adolescent girls.

Stereotypical beliefs about appearance: implications for retailing and consumer issues.

PubMed

Jasper, C R; Klassen, M L

1990-10-01

This research was designed to identify current stereotypical beliefs about obese men and women, assess subjects' desire to work with individuals described as "normal" weight as opposed to obese, examine subjects' perceptions of their own body size, inquire about subjects' personal desire to gain and lose weight, and identify subjects' diet and consumption behavior. The data indicate sex differences in subjects' perceptions of bodily appearance, desire to work with obese people, perceptions of their own weight, desire to lose rather than gain weight, and consumption and diet behavior.

Drawings reflect a new dimension of the psychological impact of long-term remission of Cushing's syndrome.

PubMed

Tiemensma, Jitske; Daskalakis, Nikolaos P; van der Veen, Else M; Ramondt, Steven; Richardson, Stephanie K; Broadbent, Elizabeth; Romijn, Johannes A; Pereira, Alberto M; Biermasz, Nienke R; Kaptein, Adrian A

2012-09-01

Drawings can be used to assess perceptions of patients about their disease. We aimed to explore the utility of the drawing test and its relation to illness perceptions, quality of life (QoL), and clinical disease severity in patients after long-term remission of Cushing's syndrome. We conducted a cross-sectional study including 47 patients with long-term remission of Cushing's syndrome. Patients completed the drawing test, the Illness Perception Questionnaire-Revised, the Short-Form 36, the EuroQoL-5D, and the Cushing QoL. The Cushing's syndrome severity index was scored based on medical records. Characteristics of the drawings were strongly associated with the Cushing's syndrome severity index and severity ratings of health professionals (all P < 0.02). In addition, patients perceived a dramatic change in body size during the active state of the disease compared to the healthy state before disease. Patients reported that their body does not completely return to the original size (i.e. before disease) after treatment. There were no clear associations between characteristics of the drawings and QoL or illness perceptions. This indicates that drawings and QoL or illness perceptions do not share multiple common properties and measure different aspects/dimensions of the disease process. Drawings reflect a new dimension of the psychological impact of long-term remission of Cushing's syndrome because drawings do not share common properties with parameters of QoL or illness perceptions, but do represent the clinical severity of the disease. The assessment of drawings may enable doctors to appreciate the perceptions of patients with long-term remission of Cushing's syndrome and will lead the way in dispelling idiosyncratic beliefs.

A Mixed Methods Comparison of Teacher Education Faculty Perceptions of the Integration of Technology into Their Courses and Student Feedback on Technology Proficiency

ERIC Educational Resources Information Center

Teclehaimanot, Berhane; Mentzer, Gale; Hickman, Torey

2011-01-01

Results from previous studies on pre-service teacher technology integration and faculty perceptions of technology integration within the teacher education program at a medium-sized, Midwestern university are compared to account for the self-reported lack of confidence pre-service teachers have integrating technology into their teaching. Also…

Self-Inference and the Foot-in-the-Door Technique: Quantity of Behavior and Attitudinal Mediation.

ERIC Educational Resources Information Center

Dillard, James Price

1990-01-01

Investigates the self-perception theory account of the foot-in-the-door (FITD) phenomenon, a sequential-request technique using a small first request followed by a larger, target request. Finds that a self-inference explanation is viable, but that a strict self-perception account fails because neither request size nor execution correspond to…

Perception of Basic Education School Teachers towards Inclusive Education in the Hohoe District of Ghana

ERIC Educational Resources Information Center

Ocloo, Mark Anthony; Subbey, Michael

2008-01-01

The purpose of this study is to investigate the perception of basic school teachers towards inclusive education in the Hohoe District of Ghana. The research makes use of a descriptive survey design, which engaged both qualitative and quantitative research methodologies. A sample size of 100 respondents, comprising of 60 male teachers and 40 female…

The effects of quantity and depth of processing on children's time perception.

PubMed

Arlin, M

1986-08-01

Two experiments were conducted to investigate the effects of quantity and depth of processing on children's time perception. These experiments tested the appropriateness of two adult time-perception models (attentional and storage size) for younger ages. Children were given stimulus sets of equal time which varied by level of processing (deep/shallow) and quantity (list length). In the first experiment, 28 children in Grade 6 reproduced presentation times of various quantities of pictures under deep (living/nonliving categorization) or shallow (repeating label) conditions. Students also compared pairs of durations. In the second experiment, 128 children in Grades K, 2, 4, and 6 reproduced presentation times under similar conditions with three or six pictures and with deep or shallow processing requirements. Deep processing led to decreased estimation of time. Higher quantity led to increased estimation of time. Comparative judgments were influenced by quantity. The interaction between age and depth of processing was significant. Older children were more affected by depth differences than were younger children. Results were interpreted as supporting different aspects of each adult model as explanations of children's time perception. The processing effect supported the attentional model and the quantity effect supported the storage size model.

The effect of phasic auditory alerting on visual perception.

PubMed

Petersen, Anders; Petersen, Annemarie Hilkjær; Bundesen, Claus; Vangkilde, Signe; Habekost, Thomas

2017-08-01

Phasic alertness refers to a short-lived change in the preparatory state of the cognitive system following an alerting signal. In the present study, we examined the effect of phasic auditory alerting on distinct perceptual processes, unconfounded by motor components. We combined an alerting/no-alerting design with a pure accuracy-based single-letter recognition task. Computational modeling based on Bundesen's Theory of Visual Attention was used to examine the effect of phasic alertness on visual processing speed and threshold of conscious perception. Results show that phasic auditory alertness affects visual perception by increasing the visual processing speed and lowering the threshold of conscious perception (Experiment 1). By manipulating the intensity of the alerting cue, we further observed a positive relationship between alerting intensity and processing speed, which was not seen for the threshold of conscious perception (Experiment 2). This was replicated in a third experiment, in which pupil size was measured as a physiological marker of alertness. Results revealed that the increase in processing speed was accompanied by an increase in pupil size, substantiating the link between alertness and processing speed (Experiment 3). The implications of these results are discussed in relation to a newly developed mathematical model of the relationship between levels of alertness and the speed with which humans process visual information. Copyright © 2017 Elsevier B.V. All rights reserved.

Use of Social Media by Spanish Hospitals: Perceptions, Difficulties, and Success Factors

PubMed Central

Bermúdez-Tamayo, Clara; Jiménez-Pernett, Jaime; García Gutiérrez, José-Francisco; Traver-Salcedo, Vicente; Yubraham-Sánchez, David

2013-01-01

Abstract This exploratory study has two aims: (1) to find out if and how social media (SM) applications are used by hospitals in Spain and (2) to assess hospital managers' perception of these applications in terms of their evaluation of them, reasons for use, success factors, and difficulties encountered during their implementation. A cross-sectional survey has been carried out using Spanish hospitals as the unit of analysis. Geographical differences in the use of SM were found. Social networks are used most often by larger hospitals (30% by medium-size, 28% by large-size). They are also more frequently used by public hospitals (19%, p<0.01) than by private ones. Respondents with a negative perception of SM felt that there is a chance they may be abused by healthcare professionals, whereas those with a positive perception believed that they can be used to improve communication both within and outside the hospital. Reasons for the use of SM include the idea of maximizing exposure of the hospital. The results show that Spanish hospitals are only just beginning to use SM applications and that hospital type can influence their use. The perceptions, reasons for use, success factors, and difficulties encountered during the implementation of SM mean that it is very important for healthcare professionals to use SM correctly and adequately. PMID:23368890

Why Barbie Feels Heavier than Ken: The Influence of Size-Based Expectancies and Social Cues on the Illusory Perception of Weight

ERIC Educational Resources Information Center

Dijker, Anton J. M.

2008-01-01

In order to examine the relative influence of size-based expectancies and social cues on the perceived weight of objects, two studies were performed, using equally weighing dolls differing in sex-related and age-related vulnerability or physical strength cues. To increase variation in perceived size, stimulus objects were viewed through optical…

Taking a Hands-On Approach: Apparent Grasping Ability Scales the Perception of Object Size

ERIC Educational Resources Information Center

Linkenauger, Sally A.; Witt, Jessica K.; Proffitt, Dennis R.

2011-01-01

We examined whether the apparent size of an object is scaled to the morphology of the relevant body part with which one intends to act on it. To be specific, we tested if the visually perceived size of graspable objects is scaled to the extent of apparent grasping ability for the individual. Previous research has shown that right-handed…

An Examination of Teachers' Perceptions and Practice when Teaching Large and Reduced-Size Classes: Do Teachers Really Teach Them in the Same Way?

ERIC Educational Resources Information Center

Harfitt, Gary James

2012-01-01

Class size research suggests that teachers do not vary their teaching strategies when moving from large to smaller classes. This study draws on interviews and classroom observations of three experienced English language teachers working with large and reduced-size classes in Hong Kong secondary schools. Findings from the study point to subtle…

Marketing and psychophysics: cornflakes and Stevens' power function.

PubMed

Clayson, D E

1994-04-01

Although major firms do not publish their pricing and packaging strategies, an analysis of 83 pairs of boxes of breakfast cereals using Stevens' Law showed that firms price their products on the perception of size rather than by actual size. By contrast, laundry detergents are priced by actual weight and volume.

Urbanism from the Perspective of Ecological Psychologists

ERIC Educational Resources Information Center

Gump, Paul V.; Adelgerg, Bettina

1978-01-01

A perception of ecological psychology on urbanism is presented, with emphasis on the following premises: (1) Urban milieu consists of complexes of behavior settings; and (2) Size of a city should be understood in relationship to the number and variety of its settings, rather than in terms of population size. (Author/MA)

The paradoxical moon illusions.

PubMed

Gilinsky, A S

1980-02-01

An adaptation theory of visual space is developed and applied to the data of a variety of studies of visual space perception. By distinguishing between the perceived distance of an object and that of the background or sky, the theory resolves the paradox of the moon illusions and relates both perceived size and perceived distance of the moon to the absolute level of spatial adaptation. The theory assumes that visual space expands or contracts in adjustment to changes in the sensory indicators of depth and provides a measure, A, of this adaptation-level. Changes in A have two effects--one on perceived size, one on perceived distance. Since A varies systematically as a function of angle of regard, availability of cues, and the total space-value, A is a measure of the moon illusions, and a practical index of individual differences by pilots and astronauts in the perception of the size and distance of objects on the ground and in the air.

Adolescent and adult perceptions of traditional and novel smokeless tobacco products and packaging in rural Ohio

PubMed Central

Liu, Sherry T.; Nemeth, Julianna M.; Klein, Elizabeth G.; Ferketich, Amy K.; Kwan, Mei-Po; Wewers, Mary Ellen

2015-01-01

Objective As smokeless tobacco (ST) marketing increases and new products emerge on the market, very little is known about consumer perceptions of ST products. To inform development of future ST counter-marketing approaches, this qualitative study examined consumer perceptions of traditional and novel ST products and packaging. Methods Focus groups and qualitative interviews were held with adolescent (n=23; mean age of 17 years) and adult (n=38; mean age of 29 years) male ST users from rural Ohio counties. Participants were shown a variety of traditional (e.g., Copenhagen®, Timber Wolf®) and novel (e.g., Camel Snus®, Orbs®) ST products and asked about perceptions of these products and their packaging. Transcriptions were coded independently for common themes by two individuals. Findings Adolescents and adults generally had similar beliefs and reactions about ST products. While participants were familiar with a variety of traditional ST products, Copenhagen® was the most frequently used product. Perceptions of quality and price of traditional products were closely tied to product taste and packaging material. Colors, design, and size of ST packaging appealed to participants and influenced decisions to purchase. Adults believed novel ST products had a weak taste and were targeted to untraditional ST users. While the vast majority was unfamiliar with dissolvable tobacco, adolescents noted that they would be more convenient to use during school than traditional ST. Conclusions Packaging has a significant role in shaping perceptions of ST and consumer behavior. Regulation of product packaging such as shape, size, and images should be part of comprehensive tobacco control. PMID:23047885

Adolescent and adult perceptions of traditional and novel smokeless tobacco products and packaging in rural Ohio.

PubMed

Liu, Sherry T; Nemeth, Julianna M; Klein, Elizabeth G; Ferketich, Amy K; Kwan, Mei-Po; Wewers, Mary Ellen

2014-05-01

As smokeless tobacco (ST) marketing increases and new products emerge on the market, very little is known about consumer perceptions of ST products. To inform development of future ST counter-marketing approaches, this qualitative study examined consumer perceptions of traditional and novel ST products and packaging. Focus groups and qualitative interviews were held with adolescent (n=23; mean age of 17 years) and adult (n=38; mean age of 29 years) male ST users from rural Ohio counties. Participants were shown a variety of traditional (eg, Copenhagen, Timber Wolf) and novel (eg, Camel Snus, Orbs) ST products and asked about perceptions of these products and their packaging. Transcriptions were coded independently for common themes by two individuals. Adolescents and adults generally had similar beliefs and reactions about ST products. While participants were familiar with a variety of traditional ST products, Copenhagen was the most frequently used product. Perceptions of quality and price of traditional products were closely tied to product taste and packaging material. Colours, design and size of ST packaging appealed to participants and influenced decisions to purchase. Adults believed novel ST products had a weak taste and were targeted at untraditional ST users. While the vast majority was unfamiliar with dissolvable tobacco, adolescents noted that they would be more convenient to use during school than traditional ST. Packaging has a significant role in shaping perceptions of ST and consumer behaviour. Regulation of product packaging such as shape, size and images should be part of comprehensive tobacco control.

Robotic surgery: current perceptions and the clinical evidence.

PubMed

Ahmad, Arif; Ahmad, Zoha F; Carleton, Jared D; Agarwala, Ashish

2017-01-01

It appears that a discrepancy exists between the perception of robotic-assisted surgery (RAS) and the current clinical evidence regarding robotic-assisted surgery among patients, healthcare providers, and hospital administrators. The purpose of this study was to assess whether or not such a discrepancy exists. We administered survey questionnaires via face-to-face interviews with surgical patients (n = 101), healthcare providers (n = 58), and senior members of hospital administration (n = 6) at a community hospital that performs robotic surgery. The respondents were asked about their perception regarding the infection rate, operative time, operative blood loss, incision size, cost, length of hospital stay (LOS), risk of complications, precision and accuracy, tactile sensation, and technique of robotic-assisted surgery as compared with conventional laparoscopic surgery. We then performed a comprehensive literature review to assess whether or not these perceptions could be corroborated with clinical evidence. The majority of survey respondents perceived RAS as modality to decrease infection rate, increase operative time, decrease operative blood loss, smaller incision size, a shorter LOS, and a lower risk of complications, while increasing the cost. Respondents also believed that robotic surgery provides greater precision, accuracy, and tactile sensation, while improving intra-operative access to organs. A comprehensive literature review found little-to-no clinical evidence that supported the respondent's favorable perceptions of robotic surgery except for the increased costs, and precision and accuracy of the robotic-assisted technique. There is a discrepancy between the perceptions of robotic surgery and the clinical evidence among patients, healthcare providers, and hospital administrators surveyed.

Food photography. I: The perception of food portion size from photographs.

PubMed

Nelson, M; Atkinson, M; Darbyshire, S

1994-11-01

Fifty-one male and female volunteers aged 18-90 years from a wide variety of social and occupational backgrounds completed 7284 assessments of portion size in relation to food photographs. Subjects were shown six portion sizes (two small, two medium and two large) for each of six foods, and asked to compare the amount on the plate in front of them to (a) a series of eight photographs showing weights of portions from the 5th to the 95th centile of portion size (British Adult Dietary Survey), or (b) a single photograph of the average (median) portion size. Photographs were prepared either in colour or in black and white, and in two different sizes. The order of presentation of foods; use of black and white or colour; the size of photographs; and presentation of eight or average photographs were each randomized independently. On average, the mean differences between the portion size presented and the estimate of portion size using the photographs varied from -8 to +6 g (-4 to +5%) for the series of eight photographs, and from -34 to -1 g (-23 to +9%) for the single average photograph. Large portion sizes tended to be underestimated more than medium or small portion sizes, especially when using the average photograph (from -79 to -14 g, -37 to -13%). Being female, 65 years and over, or retired, or seeing photographs in colour, were all associated with small but statistically significant overestimations of portion size. Having a body mass index > or = 30 kg/m2 was associated with an 8% underestimate of portion size. We conclude that use of a series of eight photographs is associated with relatively small errors in portion size perception, whereas use of an average photograph is consistently associated with substantial underestimation across a variety of foods.

Thinking big: the effect of sexually objectifying music videos on bodily self-perception in young women.

PubMed

Mischner, Isabelle H S; van Schie, Hein T; Wigboldus, Daniël H J; van Baaren, Rick B; Engels, Rutger C M E

2013-01-01

The present study investigated the effect of sexually objectifying music video exposure on young women's implicit bodily self-perception and the moderating role of self-esteem. Fifty-six college women of normal weight were either exposed to three sexually objectifying music videos or three neutral music videos. Perceived and ideal body size were measured both before and after video exposure, using horizontally stretched and compressed photographs of the participant's own body in swimming garment. As expected, only women low (but not high) in self-esteem were negatively affected by the sexually objectifying content of the music videos: they perceived themselves as bigger and showed an increased discrepancy between their perceived and ideal body size after video exposure. The neutral music videos did not influence women's bodily self-perceptions. These findings suggest that body image is a flexible construct, and that high self-esteem can protect women against the adverse effects of sexually objectifying media. Copyright © 2012 Elsevier Ltd. All rights reserved.

The malleability of gender stereotypes: influence of population size on perceptions of men and women in the past, present, and future.

PubMed

Garcia-Retamero, Rocio; Müller, Stephanie M; López-Zafra, Esther

2011-01-01

Recent studies on the malleability of gender stereotypes show that they are flexible, dynamic structures that change with the passage of time. In a study, we examined perceptions about men and women of the past, present, and future in Spain and focused on the influence of an important demographic variable on these perceptions: the population size of people's location of residence. Results showed that people perceived an increase in similarity of men and women from the past to the present and from the present to the future. In less-populated locations, however, men and women were more gender stereotyped and, consequently, still perceived to be further from equality than those in more populated areas. We concluded that the study of dynamic gender stereotypes benefits from extensive research in populations that vary in their demographic characteristics and shows the importance of recent movements in rural areas supporting women's participation in the modernization process.

A neural basis for the spatial suppression of visual motion perception

PubMed Central

Liu, Liu D; Haefner, Ralf M; Pack, Christopher C

2016-01-01

In theory, sensory perception should be more accurate when more neurons contribute to the representation of a stimulus. However, psychophysical experiments that use larger stimuli to activate larger pools of neurons sometimes report impoverished perceptual performance. To determine the neural mechanisms underlying these paradoxical findings, we trained monkeys to discriminate the direction of motion of visual stimuli that varied in size across trials, while simultaneously recording from populations of motion-sensitive neurons in cortical area MT. We used the resulting data to constrain a computational model that explained the behavioral data as an interaction of three main mechanisms: noise correlations, which prevented stimulus information from growing with stimulus size; neural surround suppression, which decreased sensitivity for large stimuli; and a read-out strategy that emphasized neurons with receptive fields near the stimulus center. These results suggest that paradoxical percepts reflect tradeoffs between sensitivity and noise in neuronal populations. DOI: http://dx.doi.org/10.7554/eLife.16167.001 PMID:27228283

Adolescent girls and young adult women's perceptions of superslims cigarette packaging: a qualitative study.

PubMed

Ford, Allison; Moodie, Crawford; Purves, Richard; MacKintosh, Anne Marie

2016-01-08

To explore perceptions of superslims packaging, including compact 'lipstick' packs, in line with 3 potential impacts identified within the impact assessment of the European Union (EU) Tobacco Products Directive: appeal, harm perceptions and the seriousness of warning of health risks. Qualitative focus group study. Informal community venues in Scotland, UK. 75 female non-smokers and occasional smokers (age range 12-24). Compact 'lipstick'-type superslims packs were perceived most positively and rated as most appealing. They were also viewed as less harmful than more standard sized cigarette packs because of their smaller size and likeness to cosmetics. Additionally, 'lipstick' packs were rated as less serious in terms of warning about the health risks associated with smoking, either because the small font size of the warnings was difficult to read or because the small pack size prevented the text on the warnings from being displayed properly. Bright pack colours and floral designs were also thought to detract from the health warning. As superslims packs were found to increase appeal, mislead with respect to level of harm, and undermine the on-pack health warnings, this provides support for the decision to ban 'lipstick'-style cigarette packs in the EU and has implications for policy elsewhere. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Risk perception of vervet monkeys Chlorocebus pygerythrus to humans in urban and rural environments.

PubMed

Mikula, Peter; Šaffa, Gabriel; Nelson, Emma; Tryjanowski, Piotr

2018-02-01

Like other animals, primates respond to predation using behavioural adaptations. Hence, they should optimise their escape strategy under the risk of predation, and flee at a distance, referred to as flight initiation distance (FID), when the fitness-related benefits of staying are balanced against the costs of escape. However, there is an absence of FID studies in primates. In this study, we used vervet monkeys Chlorocebus pygerythrus, a medium-sized African cercopithecoid, as a model species to investigate the influence of environment type (urban and rural), group size (defined as the number of visible neighbours), sex and age on FID when approached by a human. We found significantly shorter FID among urban than rural monkeys; urban individuals delayed their escape compared to rural individuals. We found no relationship between FID and sex and age class, but FID was positively correlated with group size in both settings; urban monkeys live in smaller groups than monkeys in rural areas. As FID and group size are important predictors of predation risk perception in primates, results suggest that, despite probable effects of habituation, vervet monkeys in Uganda adjust their antipredator behaviour when coping with novel environments within human settlements. Our findings are consistent with some previous studies of risk perception in animals, and indicate that FID could be used as an alternative measure for predation risk in primates. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Fairness-Based Tasks for Assessing Children’s Perceptions of Food Quantities and Associations with Portion Selection

PubMed Central

Ferrage, Aurore; Godinot, Nicolas

2018-01-01

It is critical to develop ecologically valid experimental methods to assess consumers’ food-related behaviors. Ad libitum approaches are often used but may not be appropriate for studies with children or with products that are not typically consumed until the individual feels full. The current study presents novel methods to assess children’s size perception and portion preference for gummy candies. In the first study, 62 children (30 boys, 32 girls) aged 6 to 9 years completed two matching tasks: one using pictures on a computer screen, and a similar task where the products were physically manipulated. Results of the two matching tasks were correlated, demonstrating that a computer-based approach could be used to predict the factors influencing children’s perception of food amount: the number, size, and shape of pieces. In the second study, a portioning measure was developed to investigate whether the factors identified in the matching tasks were confirmed in a task that more closely represented portion selection in the real world. The effects observed in the matching tasks could not be replicated in the portioning task. The size of each item had no significant impact on the portion selection, suggesting that it may be possible to reduce the size of pieces in snacks where multiple pieces are typically consumed without negatively impacting perceived quantity in children, thus offering a promising strategy to nudge children toward choosing smaller portions. PMID:29642371

Lecturers and Postgraduates Perception of Libraries as Promoters of Teaching, Learning, and Research at the University of Ibadan, Nigeria

ERIC Educational Resources Information Center

Oyewole, Olawale; Adetimirin, Airen

2015-01-01

Lecturers and postgraduates are among the users of the university libraries and their perception of the libraries has influence on utilization of the information resources, hence the need for this study. Survey method was adopted for the study and simple random sampling method was used to select sample size of 38 lecturers and 233 postgraduates.…

Mothers Don't Have Long Hair: An Exploratory Study of Preschool Perceptions of Mother.

ERIC Educational Resources Information Center

Denne, Joan M.

A class of preschoolers, aged 44-63 months and grouped according to age, sex, sibling position, family size and the occupation of each parent, were the subjects of a 2-part study to examine preschoolers' perceptions of mothers. In the first part of the study, each child was shown 4 sets of pictures depicting a variety of possible mother figures.…

Metabolic rate and body size are linked with perception of temporal information☆

PubMed Central

Healy, Kevin; McNally, Luke; Ruxton, Graeme D.; Cooper, Natalie; Jackson, Andrew L.

2013-01-01

Body size and metabolic rate both fundamentally constrain how species interact with their environment, and hence ultimately affect their niche. While many mechanisms leading to these constraints have been explored, their effects on the resolution at which temporal information is perceived have been largely overlooked. The visual system acts as a gateway to the dynamic environment and the relative resolution at which organisms are able to acquire and process visual information is likely to restrict their ability to interact with events around them. As both smaller size and higher metabolic rates should facilitate rapid behavioural responses, we hypothesized that these traits would favour perception of temporal change over finer timescales. Using critical flicker fusion frequency, the lowest frequency of flashing at which a flickering light source is perceived as constant, as a measure of the maximum rate of temporal information processing in the visual system, we carried out a phylogenetic comparative analysis of a wide range of vertebrates that supported this hypothesis. Our results have implications for the evolution of signalling systems and predator–prey interactions, and, combined with the strong influence that both body mass and metabolism have on a species' ecological niche, suggest that time perception may constitute an important and overlooked dimension of niche differentiation. PMID:24109147

Maternal and child awareness and expectations of child overweight.

PubMed

Brødsgaard, Anne; Wagner, Lis; Peitersen, Birgit; Poulsen, Ingrid; Sørensen, Thorkild I A

2011-01-01

We investigated mothers' and children's assessments of body weight and their expectations about perceived body size in relation to overweight of the children. We performed a case-control study of 111 cases of overweight children and 149 controls of non-overweight children (mean age 8.1 years) and their mothers. All were examined and interviewed about their assessment of body weight and their perception of a normal, attractive and acceptable body size. Case children were less able than control children to correctly assess their own body weight (p < 0.001), as were mothers of overweight children (MOC) to assess their children's body weight (p < 0.001). The majority of mothers from both groups wished their children to have a normal body size, but 18% of MOC wished their children to have an overweight body size (p < 0.013). The majority of case children, control children and mothers found a normal body size for boys and girls to be the most attractive and socially acceptable, but more MOC found overweight among boys to be the most attractive (p = 0.006). Overweight children and their mothers show increased uncertainty in the assessment of overweight and obesity, but the perception of a normal, attractive and socially acceptable body size is not distorted. Copyright © 2011 S. Karger AG, Basel.

Obesity, appearance, and psychosocial adaptation in young African American children.

PubMed

Young-Hyman, Deborah; Schlundt, David G; Herman-Wenderoth, Leanna; Bozylinski, Khristine

2003-01-01

To evaluate the contributions of weight status, skin tone, peer teasing, and parental appraisals of child's size to self-esteem and psychosocial adjustment in overweight African American children. Overweight to very obese 5- to 10-year-old African American children (N = 117) completed measures of self-esteem, skin tone satisfaction, peer teasing, and body size perception. Caregivers completed the Child Behavior Checklist and rated their child's body size. Overweight was associated with low appearance self-esteem, and body size dissatisfaction with low global self-worth and low appearance self-esteem in children 8 and older. Appearance self-esteem but not global self-worth was lower in girls than boys. Parental perception of child's size as heavier than average was associated with low child appearance self-esteem. Heavier children also had more parental report of behavior and psychosocial problems, but their scores were in the nonclinical range. Child skin tone dissatisfaction was associated with low global self-worth. Weight-related peer teasing was associated with low self-esteem. The relationship between obesity and self-esteem in African American children depends upon age, gender, and children's experiences with teasing and parental evaluation of their size. Other factors, like skin tone satisfaction, contribute to a child's sense of self-worth.

The consequences of perceived discrimination for psychological well-being: a meta-analytic review.

PubMed

Schmitt, Michael T; Branscombe, Nyla R; Postmes, Tom; Garcia, Amber

2014-07-01

In 2 meta-analyses, we examined the relationship between perceived discrimination and psychological well-being and tested a number of moderators of that relationship. In Meta-Analysis 1 (328 independent effect sizes, N = 144,246), we examined correlational data measuring both perceived discrimination and psychological well-being (e.g., self-esteem, depression, anxiety, psychological distress, life satisfaction). Using a random-effects model, the mean weighted effect size was significantly negative, indicating harm (r = -.23). Effect sizes were larger for disadvantaged groups (r = -.24) compared to advantaged groups (r = -.10), larger for children compared to adults, larger for perceptions of personal discrimination compared to group discrimination, and weaker for racism and sexism compared to other stigmas. The negative relationship was significant across different operationalizations of well-being but was somewhat weaker for positive outcomes (e.g., self-esteem, positive affect) than for negative outcomes (e.g., depression, anxiety, negative affect). Importantly, the effect size was significantly negative even in longitudinal studies that controlled for prior levels of well-being (r = -.15). In Meta-Analysis 2 (54 independent effect sizes, N = 2,640), we examined experimental data from studies manipulating perceptions of discrimination and measuring well-being. We found that the effect of discrimination on well-being was significantly negative for studies that manipulated general perceptions of discrimination (d = -.25), but effects did not differ from 0 when attributions to discrimination for a specific negative event were compared to personal attributions (d = .06). Overall, results support the idea that the pervasiveness of perceived discrimination is fundamental to its harmful effects on psychological well-being. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Optical Extinction Measurements of Dust Density in the GMRO Regolith Test Bin

NASA Technical Reports Server (NTRS)

Lane, J.; Mantovani, J.; Mueller, R.; Nugent, M.; Nick, A.; Schuler, J.; Townsend, I.

2016-01-01

A regolith simulant test bin was constructed and completed in the Granular Mechanics and Regolith Operations (GMRO) Lab in 2013. This Planetary Regolith Test Bed (PRTB) is a 64 sq m x 1 m deep test bin, is housed in a climate-controlled facility, and contains 120 MT of lunar-regolith simulant, called Black Point-1 or BP-1, from Black Point, AZ. One of the current uses of the test bin is to study the effects of difficult lighting and dust conditions on Telerobotic Perception Systems to better assess and refine regolith operations for asteroid, Mars and polar lunar missions. Low illumination and low angle of incidence lighting pose significant problems to computer vision and human perception. Levitated dust on Asteroids interferes with imaging and degrades depth perception. Dust Storms on Mars pose a significant problem. Due to these factors, the likely performance of telerobotics is poorly understood for future missions. Current space telerobotic systems are only operated in bright lighting and dust-free conditions. This technology development testing will identify: (1) the impact of degraded lighting and environmental dust on computer vision and operator perception, (2) potential methods and procedures for mitigating these impacts, (3) requirements for telerobotic perception systems for asteroid capture, Mars dust storms and lunar regolith ISRU missions. In order to solve some of the Telerobotic Perception system problems, a plume erosion sensor (PES) was developed in the Lunar Regolith Simulant Bin (LRSB), containing 2 MT of JSC-1a lunar simulant. PES is simply a laser and digital camera with a white target. Two modes of operation have been investigated: (1) single laser spot - the brightness of the spot is dependent on the optical extinction due to dust and is thus an indirect measure of particle number density, and (2) side-scatter - the camera images the laser from the side, showing beam entrance into the dust cloud and the boundary between dust and void. Both methods must assume a mean particle size in order to extract a number density. The optical extinction measurement yields the product of the 2nd moment of the particle size distribution and the extinction efficiency Qe. For particle sizes in the range of interest (greater than 1 micrometer), Qe approximately equal to 2. Scaling up of the PES single laser and camera system is underway in the PRTB, where an array of lasers penetrate a con-trolled dust cloud, illuminating multiple targets. Using high speed HD GoPro video cameras, the evolution of the dust cloud and particle size density can be studied in detail.

Characterization of an air jet haptic lump display.

PubMed

Bianchi, Matteo; Gwilliam, James C; Degirmenci, Alperen; Okamura, Allison M

2011-01-01

During manual palpation, clinicians rely on distributed tactile information to identify and localize hard lumps embedded in soft tissue. The development of tactile feedback systems to enhance palpation using robot-assisted minimally invasive surgery (RMIS) systems is challenging due to size and weight constraints, motivating a pneumatic actuation strategy. Recently, an air jet approach has been proposed for generating a lump percept. We use this technique to direct a thin stream of air through an aperture directly on the finger pad, which indents the skin in a hemispherical manner, producing a compelling lump percept. We hypothesize that the perceived parameters of the lump (e.g. size and stiffness) can be controlled by jointly adjusting air pressure and the aperture size through which air escapes. In this work, we investigate how these control variables interact to affect perceived pressure on the finger pad. First, we used a capacitive tactile sensor array to measure the effect of aperture size on output pressure, and found that peak output pressure increases with aperture size. Second, we performed a psychophysical experiment for each aperture size to determine the just noticeable difference (JND) of air pressure on the finger pad. Subject-averaged pressure JND values ranged from 19.4-24.7 kPa, with no statistical differences observed between aperture sizes. The aperture-pressure relationship and the pressure JND values will be fundamental for future display control.

Colour Size Illusion on Liquid Crystal Displays and Design Guidelines for Bioinformatics Tools

ERIC Educational Resources Information Center

Yoo, Hyun Seung; Smith-Jackson, Tonya L.

2011-01-01

Although the influence of colour on size perception has been known for a century, there is only limited research on interventions that can reduce this effect. This study was therefore undertaken in order to identify appropriate interventions and propose design guidelines for information visualisation, especially in applications where size…

Class Size: Teachers' Perspectives

ERIC Educational Resources Information Center

Watson, Kevin; Handal, Boris; Maher, Marguerite

2016-01-01

A consistent body of research shows that large classes have been perceived by teachers as an obstacle to deliver quality teaching. This large-scale study sought to investigate further those differential effects by asking 1,119 teachers from 321 K-12 schools in New South Wales (Australia) their perceptions of ideal class size for a variety of…

Visual illusions and plate design: the effects of plate rim widths and rim coloring on perceived food portion size.

PubMed

McClain, A D; van den Bos, W; Matheson, D; Desai, M; McClure, S M; Robinson, T N

2014-05-01

The Delboeuf Illusion affects perceptions of the relative sizes of concentric shapes. This study was designed to extend research on the application of the Delboeuf illusion to food on a plate by testing whether a plate's rim width and coloring influence perceptual bias to affect perceived food portion size. Within-subjects experimental design. Experiment 1 tested the effect of rim width on perceived food portion size. Experiment 2 tested the effect of rim coloring on perceived food portion size. In both experiments, participants observed a series of photographic images of paired, side-by-side plates varying in designs and amounts of food. From each pair, participants were asked to select the plate that contained more food. Multilevel logistic regression examined the effects of rim width and coloring on perceived food portion size. Experiment 1: participants overestimated the diameter of food portions by 5% and the visual area of food portions by 10% on plates with wider rims compared with plates with very thin rims (P<0.0001). The effect of rim width was greater with larger food portion sizes. Experiment 2: participants overestimated the diameter of food portions by 1.5% and the visual area of food portions by 3% on plates with rim coloring compared with plates with no coloring (P=0.01). The effect of rim coloring was greater with smaller food portion sizes. The Delboeuf illusion applies to food on a plate. Participants overestimated food portion size on plates with wider and colored rims. These findings may help design plates to influence perceptions of food portion sizes.

An overture to overeating: The cross-modal effects of acoustic pitch on food preferences and serving behavior.

PubMed

Lowe, Michael; Ringler, Christine; Haws, Kelly

2018-04-01

Billions of dollars are spent annually with the aim of enticing consumers to purchase food. Yet despite the prevalence of such advertising, little is known about how the actual sensation of this advertising media affects consumer behavior, including consequential choices regarding food. This paper explores the effect of acoustic pitch in food advertising, demonstrating in two studies, including a field study in a live retail environment, how the perception of pitch in advertising can impact food desirability and decisions regarding serving size. In study 1, a field study, pitch affects actual serving sizes and purchase behavior in a live, self-serve retail setting, with low pitch leading to larger serving sizes. Study 2 demonstrates how low pitch increases desire for a food product among hungry consumers, and that this effect is mediated by perceptions of size and how filling consumers believe the product will be. We discuss these results in the context of cross-modal correspondence and mental imagery. Copyright © 2017 Elsevier Ltd. All rights reserved.

Stereoscopic depth perception varies with hues

NASA Astrophysics Data System (ADS)

Chen, Zaiqing; Shi, Junsheng; Tai, Yonghang; Yun, Lijun

2012-09-01

The contribution of color information to stereopsis is controversial, and whether the stereoscopic depth perception varies with chromaticity is ambiguous. This study examined the changes in depth perception caused by hue variations. Based on the fact that a greater disparity range indicates more efficient stereoscopic perception, the effect of hue variations on depth perception was evaluated through the disparity range with random-dot stereogram stimuli. The disparity range was obtained by constant-stimulus method for eight chromaticity points sampled from the CIE 1931 chromaticity diagram. Eight sample points include four main color hues: red, yellow, green, and blue at two levels of chroma. The results show that the disparity range for the yellow hue is greater than the red hue, the latter being greater than the blue hue and the disparity range for green hue is smallest. We conclude that the perceived depth is not the same for different hues for a given size of disparity. We suggest that the stereoscopic depth perception can vary with chromaticity.

Hospitals' organizational variables and patients' perceptions of individualized nursing care in Finland.

PubMed

Suhonen, Riitta; Välimäki, Maritta; Katajisto, Jouko; Leino-Kilpi, Helena

2007-03-01

To examine the association between hospitals' organizational variables and patients' perceptions of individualized care. There is lack of evidence related to the effects that the hospital environment has on patient perceptions of the individuality of care they receive. A cross-sectional design was used. The questionnaire survey data were obtained from 861 (response rate 82%) hospital patients and 35 (100%) nurse managers in Finland. Results An inverse relationship between the size of the hospital and ward and patients' perceptions of individualized care was found. Increased staffing or skill mix failed to predict a higher patient perception of individualized care, but primary nursing care delivery did. Instead of increasing the amount of nursing staff, there is a need to improve the quality of the nurse-patient interactions to facilitate individualized care. The generalizability of the study is limited by the regional nature of the setting.

How we perceive our own retina.

PubMed

Kirschfeld, Kuno

2017-10-25

Ever since the days of René Descartes, in the seventeenth century, the search for the relationship between subjective perception and neural activity has been an ongoing challenge. In neuroscience, an approach to the problem via the visual system has produced a paradigm using perceptual suppression, changing with time. Cortical areas in which the neural activity was modulated in temporal correlation with this percept could be traced. Although these areas may lead directly to perception, such temporal correlation of neural activity does not suffice as ultimate proof that they actually do so. In this article, I will use a different method to show that, for the perception of our own retina, any brain area leading directly to this perception also needs to represent the retina without distortion. Furthermore, I will demonstrate that the phenomenon of size constancy must be realized in this area. © 2017 The Authors.

The role of motor simulation in action perception: a neuropsychological case study.

PubMed

Eskenazi, Terry; Grosjean, Marc; Humphreys, Glyn W; Knoblich, Guenther

2009-07-01

Research on embodied cognition stresses that bodily and motor processes constrain how we perceive others. Regarding action perception the most prominent hypothesis is that observed actions are matched to the observer's own motor representations. Previous findings demonstrate that the motor laws that constrain one's performance also constrain one's perception of others' actions. The present neuropsychological case study asked whether neurological impairments affect a person's performance and action perception in the same way. The results showed that patient DS, who suffers from a frontal brain lesion, not only ignored target size when performing movements but also when asked to judge whether others can perform the same movements. In other words DS showed the same violation of Fitts's law when performing and observing actions. These results further support the assumption of close perception action links and the assumption that these links recruit predictive mechanisms residing in the motor system.

Comparative studies of perceived vibration strength for commercial mobile phones.

PubMed

Lee, Heow Pueh; Lim, Siak Piang

2014-05-01

A mobile phone, also known as cell phone or hand phone, is among the most popular electrical devices used by people all over the world. The present study examines the vibration perception of mobile phones by co-relating the relevant design parameters such as excitation frequency, and size and mass of mobile phones to the vibration perception survey by volunteers. Five popular commercially available mobile phone models were tested. The main findings for the perception surveys were that higher vibration frequency and amplitude of the peak acceleration would result in stronger vibration perception of the mobile phones. A larger contact surface area with the palms and figures, higher peak acceleration and the associated larger peak inertia force may be the main factors for the relatively higher vibration perception. The future design for the vibration alert of the mobile phones is likely to follow this trend. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Speech Perception and Short Term Memory Deficits in Persistent Developmental Speech Disorder

PubMed Central

Kenney, Mary Kay; Barac-Cikoja, Dragana; Finnegan, Kimberly; Jeffries, Neal; Ludlow, Christy L.

2008-01-01

Children with developmental speech disorders may have additional deficits in speech perception and/or short-term memory. To determine whether these are only transient developmental delays that can accompany the disorder in childhood or persist as part of the speech disorder, adults with a persistent familial speech disorder were tested on speech perception and short-term memory. Nine adults with a persistent familial developmental speech disorder without language impairment were compared with 20 controls on tasks requiring the discrimination of fine acoustic cues for word identification and on measures of verbal and nonverbal short-term memory. Significant group differences were found in the slopes of the discrimination curves for first formant transitions for word identification with stop gaps of 40 and 20 ms with effect sizes of 1.60 and 1.56. Significant group differences also occurred on tests of nonverbal rhythm and tonal memory, and verbal short-term memory with effect sizes of 2.38, 1.56 and 1.73. No group differences occurred in the use of stop gap durations for word identification. Because frequency-based speech perception and short-term verbal and nonverbal memory deficits both persisted into adulthood in the speech-impaired adults, these deficits may be involved in the persistence of speech disorders without language impairment. PMID:15896836

Audiovisual speech perception in infancy: The influence of vowel identity and infants' productive abilities on sensitivity to (mis)matches between auditory and visual speech cues.

PubMed

Altvater-Mackensen, Nicole; Mani, Nivedita; Grossmann, Tobias

2016-02-01

Recent studies suggest that infants' audiovisual speech perception is influenced by articulatory experience (Mugitani et al., 2008; Yeung & Werker, 2013). The current study extends these findings by testing if infants' emerging ability to produce native sounds in babbling impacts their audiovisual speech perception. We tested 44 6-month-olds on their ability to detect mismatches between concurrently presented auditory and visual vowels and related their performance to their productive abilities and later vocabulary size. Results show that infants' ability to detect mismatches between auditory and visually presented vowels differs depending on the vowels involved. Furthermore, infants' sensitivity to mismatches is modulated by their current articulatory knowledge and correlates with their vocabulary size at 12 months of age. This suggests that-aside from infants' ability to match nonnative audiovisual cues (Pons et al., 2009)-their ability to match native auditory and visual cues continues to develop during the first year of life. Our findings point to a potential role of salient vowel cues and productive abilities in the development of audiovisual speech perception, and further indicate a relation between infants' early sensitivity to audiovisual speech cues and their later language development. PsycINFO Database Record (c) 2016 APA, all rights reserved.

Turbidity in oil-in-water-emulsions - Key factors and visual perception.

PubMed

Linke, C; Drusch, S

2016-11-01

The aim of the present study is to systematically describe the factors affecting turbidity in beverage emulsions and to get a better understanding of visual perception of turbidity. The sensory evaluation of the human visual perception of turbidity showed that humans are most sensitive to turbidity differences between two samples in the range between 1000 and 1500 NTU (ratio) (nephelometric turbidity units). At very high turbidity values >2000 TU in NTU (ratio) were needed to distinguish between samples that they were perceived significantly different. Particle size was the most important factor affecting turbidity. It was shown that a maximum turbidity occurs at a mean volume - surface diameter of 0.2μm for the oil droplet size. Additional parameters were the refractive index, the composition of the aqueous phase and the presence of excess emulsifier. In a concentration typical for a beverage emulsion a change in the refractive index of the oil phase may allow the alteration of turbidity by up to 30%. With the knowledge on visual perception of turbidity and the determining factors, turbidity can be tailored in product development according to the customer requirements and in quality control to define acceptable variations in optical appearance. Copyright © 2016. Published by Elsevier Ltd.

Grasping isoluminant stimuli.

PubMed

Kleinholdermann, Urs; Franz, Volker H; Gegenfurtner, Karl R; Stockmeier, Kerstin

2009-07-01

We used a virtual reality setup to let participants grasp discs, which differed in luminance, chromaticity and size. Current theories on perception and action propose a division of labor in the brain into a color proficient perception pathway and a less color-capable action pathway. In this study, we addressed the question whether isoluminant stimuli, which provide only a chromatic but no luminance contrast for action planning, are harder to grasp than stimuli providing luminance contrast or both kinds of contrast. Although we found that grasps of isoluminant stimuli had a slightly steeper slope relating the maximum grip aperture to disc size, all other measures of grip quality were unaffected. Overall, our results do not support the view that isoluminance of stimulus and background impedes the planning of a grasping movement.

BMI-based body size guides for women and men: development and validation of a novel pictorial method to assess weight-related concepts.

PubMed

Harris, C V; Bradlyn, A S; Coffman, J; Gunel, E; Cottrell, L

2008-02-01

To develop and evaluate two BMI-based instruments to determine perceptions of weight status, particularly perceptions of overweight and obesity, using pictorial images of women and men. Pictures of adults with known BMI values were used to construct gender-specific body size guides (BSGs) containing 10 bodies that ranged from underweight to class III obesity. Figures were standardized and a composite face was added to each. The BSGs were administered to 400 adults to assess the psychometric properties of the instruments and weight perceptions. High correlations between the BMIs of respondents and the BMIs of the current body selected by respondents provided strong support for the criterion-related validity of the BSGs, and the logical pattern of responses to items assessing perception of weight categories supported construct validity for the scales. Test-retest reliability, assessed by correlations for both current and ideal body, was also high, despite the lengthy 6-month testing interval. Respondents' perceptions of the bodies within specific weight categories indicated that a majority failed to recognize the overweight female as overweight and perceived the overweight male as normal weight. Obese bodies were generally unrecognized as such until the bodies reached the higher levels of obesity (that is, BMI values >39). Perception of weight was influenced by the respondents' weight status and gender. Psychometric analyses indicated the BSGs are valid and reliable instruments. These results, coupled with the face validity of the scales and the relationship between the bodies and BMI values, indicate the BSGs offer advantages over existing instruments for researchers of weight perception and body image. Administration of the scales to an adult sample confirmed that overweight and obesity are under-recognized. Increased efforts to improve public understanding of these terms are needed and the BSGs may provide useful tools for this purpose.

Comparing Novice and Expert Perceptions of Interactive Multimedia Tools for Conveying Conceptions of Size and Scale

ERIC Educational Resources Information Center

Magana, Alejandra; Newby, Timothy; Brophy, Sean

2012-01-01

Education in nanotechnology presents major challenges in science literacy. One of these challenges relates to conveying size and scale-related concepts. Because of the potential difficulties in conveying concepts and ideas that are not visible to the naked eye, multimedia for learning could be an appropriate vehicle to deliver curricular materials…

The Education and Skills Gap: A Global Crisis

ERIC Educational Resources Information Center

Cornelius, Dave

2011-01-01

It is like trying to fit a triangular peg into a round hole while both the hole and the peg continually change shape and size. Sound a little crazy? That is just what industry thinks about the current global "one-size-fits-all" concept of education. The perception from business, government and education leaders of 50 nations at the…

Cognitive Processing about Classroom-Relevant Contexts: Teachers' Attention to and Utilization of Girls' Body Size, Ethnicity, Attractiveness, and Facial Affect

ERIC Educational Resources Information Center

Wang, Shirley S.; Treat, Teresa A.; Brownell, Kelly D.

2008-01-01

This study examines 2 aspects of cognitive processing in person perception--attention and decision making--in classroom-relevant contexts. Teachers completed 2 implicit, performance-based tasks that characterized attention to and utilization of 4 student characteristics of interest: ethnicity, facial affect, body size, and attractiveness. Stimuli…

What Does School Size Do: Safety Perceptions of Educators and Students

ERIC Educational Resources Information Center

Bakioglu, Aysen; Geyin, Cigdem

2009-01-01

The purpose of this study is to find out how teachers, principals, vice principals and students perceive school safety and how that differs related to school size. 194 educators and 1420 students' views were elicited by two self-deviced school safety inventories conducted in 10 state high schools in Istanbul in 2008. Cronbach alpha value for…

Data on German farmers risk preference, perception and management strategies.

PubMed

Meraner, Manuela; Finger, Robert

2017-12-01

The extent to which people are willing to take on risk, i.e. their risk preferences as well as subjective risk perception plays a major role in explaining their behavior. This is of particular relevance in agricultural production, which is inherently risky. The data presented here was collected amongst a total of 64 German farmers in 2015. It includes results of three different risk preference elicitation methods (multiple price list, business statements in four relevant domains and general self-assessment) as well as risk perception. Additionally, farm business characteristics (e.g. size, farm-level workforce, succession) and personal farmer characteristics (e.g. age, gender, risk literacy) are included.

An Evaluation of the Perceptions of Multicultural Knowledge and Multicultural Awareness between Graduating Counselor Education Students with Beginning Counselor Education Students Who Have Recently Completed a Course in Multicultural Issues and Strategies in Counseling

ERIC Educational Resources Information Center

Santos, Tad Pierre

2012-01-01

This was a study of student perceptions and retention of multicultural counseling awareness and knowledge. All of the graduate students of a medium sized, private university in Pennsylvania, in the counselor education program (included marriage and family, school counseling, and community counseling tracks) were required to take the Multicultural…

Perceptions and beliefs about body size, weight, and weight loss among obese African American women: a qualitative inquiry.

PubMed

Befort, Christie A; Thomas, Janet L; Daley, Christine M; Rhode, Paula C; Ahluwalia, Jasjit S

2008-06-01

The purpose of this qualitative study was to explore perceptions and beliefs about body size, weight, and weight loss among obese African American women in order to form a design of weight loss intervention with this target population. Six focus groups were conducted at a community health clinic. Participants were predominantly middle-aged with a mean Body Mass Index of 40.3 +/- 9.2 kg/m(2). Findings suggest that participants (a) believe that people can be attractive and healthy at larger sizes; (b) still feel dissatisfied with their weight and self-conscious about their bodies; (c) emphasize eating behavior as the primary cause for weight gain; (d) view pregnancy, motherhood, and caregiving as major precursors to weight gain; (e) view health as the most important reason to lose weight; (f) have mixed experiences and expectations for social support for weight loss; and (g) prefer treatments that incorporate long-term lifestyle modification rather than fad diets or medication.

From the Cover: Explaining the moon illusion

NASA Astrophysics Data System (ADS)

Kaufman, Lloyd; Kaufman, James H.

2000-01-01

An old explanation of the moon illusion holds that various cues place the horizon moon at an effectively greater distance than the elevated moon. Although both moons have the same angular size, the horizon moon must be perceived as larger. More recent explanations hold that differences in accommodation or other factors cause the elevated moon to appear smaller. As a result of this illusory difference in size, the elevated moon appears to be more distant than the horizon moon. These two explanations, both based on the geometry of stereopsis, lead to two diametrically opposed hypotheses. That is, a depth interval at a long distance is associated with a smaller binocular disparity, whereas an equal depth interval at a smaller distance is associated with a larger disparity. We conducted experiments involving artificial moons and confirmed the hypothesis that the horizon moon is at a greater perceptual distance. Moreover, when a moon of constant angular size was moved closer it was also perceived as growing smaller, which is consistent with the older explanation. Although Emmert's law does not predict the size-distance relationship over long distances, we conclude that the horizon moon is perceived as larger because the perceptual system treats it as though it is much farther away. Finally, we observe that recent explanations substitute perceived size for angular size as a cue to distance. Thus, they imply that perceptions cause perceptions.

Moon illusion and spiral aftereffect: illusions due to the loom-zoom system?

PubMed

Hershenson, M

1982-12-01

The moon illusion and the spiral aftereffect are illusions in which apparent size and apparent distance vary inversely. Because this relationship is exactly opposite to that predicted by the static size--distance invariance hypothesis, the illusions have been called "paradoxical." The illusions may be understood as products of a loom-zoom system, a hypothetical visual subsystem that, in its normal operation, acts according to its structural constraint, the constancy axiom, to produce perceptions that satisfy the constraints of stimulation, the kinetic size--distance invariance hypothesis. When stimulated by its characteristic stimulus of symmetrical expansion or contraction, the loom-zoom system produces the perception of a rigid object moving in depth. If this system is stimulated by a rotating spiral, a negative motion-aftereffect is produced when rotation ceases. If fixation is then shifted to a fixed-sized disc, the aftereffect process alters perceived distance and the loom-zoom system alters perceived size such that the disc appears to expand and approach or to contract and recede, depending on the direction of rotation of the spiral. If the loom-zoom system is stimulated by a moon-terrain configuration, the equidistance tendency produces a foreshortened perceived distance for the moon as an inverse function of elevation and acts in conjunction with the loom-zoom system to produce the increased perceived size of the moon.

Front-Presented Looming Sound Selectively Alters the Perceived Size of a Visual Looming Object.

PubMed

Yamasaki, Daiki; Miyoshi, Kiyofumi; Altmann, Christian F; Ashida, Hiroshi

2018-07-01

In spite of accumulating evidence for the spatial rule governing cross-modal interaction according to the spatial consistency of stimuli, it is still unclear whether 3D spatial consistency (i.e., front/rear of the body) of stimuli also regulates audiovisual interaction. We investigated how sounds with increasing/decreasing intensity (looming/receding sound) presented from the front and rear space of the body impact the size perception of a dynamic visual object. Participants performed a size-matching task (Experiments 1 and 2) and a size adjustment task (Experiment 3) of visual stimuli with increasing/decreasing diameter, while being exposed to a front- or rear-presented sound with increasing/decreasing intensity. Throughout these experiments, we demonstrated that only the front-presented looming sound caused overestimation of the spatially consistent looming visual stimulus in size, but not of the spatially inconsistent and the receding visual stimulus. The receding sound had no significant effect on vision. Our results revealed that looming sound alters dynamic visual size perception depending on the consistency in the approaching quality and the front-rear spatial location of audiovisual stimuli, suggesting that the human brain differently processes audiovisual inputs based on their 3D spatial consistency. This selective interaction between looming signals should contribute to faster detection of approaching threats. Our findings extend the spatial rule governing audiovisual interaction into 3D space.

Explaining the moon illusion.

PubMed

Kaufman, L; Kaufman, J H

2000-01-04

An old explanation of the moon illusion holds that various cues place the horizon moon at an effectively greater distance than the elevated moon. Although both moons have the same angular size, the horizon moon must be perceived as larger. More recent explanations hold that differences in accommodation or other factors cause the elevated moon to appear smaller. As a result of this illusory difference in size, the elevated moon appears to be more distant than the horizon moon. These two explanations, both based on the geometry of stereopsis, lead to two diametrically opposed hypotheses. That is, a depth interval at a long distance is associated with a smaller binocular disparity, whereas an equal depth interval at a smaller distance is associated with a larger disparity. We conducted experiments involving artificial moons and confirmed the hypothesis that the horizon moon is at a greater perceptual distance. Moreover, when a moon of constant angular size was moved closer it was also perceived as growing smaller, which is consistent with the older explanation. Although Emmert's law does not predict the size-distance relationship over long distances, we conclude that the horizon moon is perceived as larger because the perceptual system treats it as though it is much farther away. Finally, we observe that recent explanations substitute perceived size for angular size as a cue to distance. Thus, they imply that perceptions cause perceptions.

Adolescents' perceptions of cigarette brand image: does plain packaging make a difference?

PubMed

Germain, Daniella; Wakefield, Melanie A; Durkin, Sarah J

2010-04-01

To examine the effect of plain packaging on adolescents' perceptions of cigarette packs, attributes of smokers, and expectations of cigarette taste, and to identify the effect of increasing the size of pictorial health warnings on appraisal of plain packs. We used a 5 (degree of plain packaging and graphic health warning)x 3 (brand type) between-subjects experimental design, using a Web-based methodology to expose adolescents to one randomly selected cigarette pack, during which respondents completed ratings. When brand elements such as color, branded fonts, and imagery were progressively removed from cigarette packs, adolescents perceived packs to be less appealing, rated attributes of a typical smoker of the pack less positively, and had more negative expectations of cigarette taste. Pack appeal was reduced even further when the size of the pictorial health warning on the most plain pack was increased from 30% to 80% of the pack face, with this effect apparent among susceptible nonsmokers, experimenters, and established smokers. Removing as much brand information from cigarette packs as possible is likely to reduce positive cigarette brand image associations among adolescents. By additionally increasing the size of pictorial health warnings, positive pack perceptions of those who are at greater risk of becoming regular addicted adult smokers are most likely to be reduced. Copyright 2010 Society for Adolescent Medicine. Published by Elsevier Inc. All rights reserved.

Visual illusions and plate design: The effects of plate rim widths and rim coloring on perceived food portion size

PubMed Central

McClain, Arianna; van den Bos, Wouter; Matheson, Donna; Desai, Manisha; McClure, Samuel M.; Robinson, Thomas N.

2013-01-01

OBJECTIVE The Delboeuf Illusion affects perceptions of the relative sizes of concentric shapes. This study was designed to extend research on the application of the Delboeuf illusion to food on a plate by testing whether a plate’s rim width and coloring influence perceptual bias to affect perceived food portion size. DESIGN AND METHODS Within-subjects experimental design. Experiment 1 tested the effect of rim width on perceived food portion size. Experiment 2 tested the effect of rim coloring on perceived food portion size. In both experiments, participants observed a series of photographic images of paired, side-by-side plates varying in designs and amounts of food. From each pair, participants were asked to select the plate that contained more food. Multi-level logistic regression examined the effects of rim width and coloring on perceived food portion size. RESULTS Experiment 1: Participants overestimated the diameter of food portions by 5% and the visual area of food portions by 10% on plates with wider rims compared to plates with very thin rims (P<0.0001). The effect of rim width was greater with larger food portion sizes. Experiment 2: Participants overestimated the diameter of food portions by 1.5% and the visual area of food portions by 3% on plates with rim coloring compared to plates with no coloring (P=0.01). The effect of rim coloring was greater with smaller food portion sizes. CONCLUSION The Delboeuf illusion applies to food on a plate. Participants overestimated food portion size on plates with wider and colored rims. These findings may help design plates to influence perceptions of food portion sizes. PMID:24005858

Owning an overweight or underweight body: distinguishing the physical, experienced and virtual body.

PubMed

Piryankova, Ivelina V; Wong, Hong Yu; Linkenauger, Sally A; Stinson, Catherine; Longo, Matthew R; Bülthoff, Heinrich H; Mohler, Betty J

2014-01-01

Our bodies are the most intimately familiar objects we encounter in our perceptual environment. Virtual reality provides a unique method to allow us to experience having a very different body from our own, thereby providing a valuable method to explore the plasticity of body representation. In this paper, we show that women can experience ownership over a whole virtual body that is considerably smaller or larger than their physical body. In order to gain a better understanding of the mechanisms underlying body ownership, we use an embodiment questionnaire, and introduce two new behavioral response measures: an affordance estimation task (indirect measure of body size) and a body size estimation task (direct measure of body size). Interestingly, after viewing the virtual body from first person perspective, both the affordance and the body size estimation tasks indicate a change in the perception of the size of the participant's experienced body. The change is biased by the size of the virtual body (overweight or underweight). Another novel aspect of our study is that we distinguish between the physical, experienced and virtual bodies, by asking participants to provide affordance and body size estimations for each of the three bodies separately. This methodological point is important for virtual reality experiments investigating body ownership of a virtual body, because it offers a better understanding of which cues (e.g. visual, proprioceptive, memory, or a combination thereof) influence body perception, and whether the impact of these cues can vary between different setups.

Owning an Overweight or Underweight Body: Distinguishing the Physical, Experienced and Virtual Body

PubMed Central

Piryankova, Ivelina V.; Wong, Hong Yu; Linkenauger, Sally A.; Stinson, Catherine; Longo, Matthew R.; Bülthoff, Heinrich H.; Mohler, Betty J.

2014-01-01

Our bodies are the most intimately familiar objects we encounter in our perceptual environment. Virtual reality provides a unique method to allow us to experience having a very different body from our own, thereby providing a valuable method to explore the plasticity of body representation. In this paper, we show that women can experience ownership over a whole virtual body that is considerably smaller or larger than their physical body. In order to gain a better understanding of the mechanisms underlying body ownership, we use an embodiment questionnaire, and introduce two new behavioral response measures: an affordance estimation task (indirect measure of body size) and a body size estimation task (direct measure of body size). Interestingly, after viewing the virtual body from first person perspective, both the affordance and the body size estimation tasks indicate a change in the perception of the size of the participant's experienced body. The change is biased by the size of the virtual body (overweight or underweight). Another novel aspect of our study is that we distinguish between the physical, experienced and virtual bodies, by asking participants to provide affordance and body size estimations for each of the three bodies separately. This methodological point is important for virtual reality experiments investigating body ownership of a virtual body, because it offers a better understanding of which cues (e.g. visual, proprioceptive, memory, or a combination thereof) influence body perception, and whether the impact of these cues can vary between different setups. PMID:25083784

Perception while watching movies: Effects of physical screen size and scene type.

PubMed

Troscianko, Tom; Meese, Timothy S; Hinde, Stephen

2012-01-01

Over the last decade, television screens and display monitors have increased in size considerably, but has this improved our televisual experience? Our working hypothesis was that the audiences adopt a general strategy that "bigger is better." However, as our visual perceptions do not tap directly into basic retinal image properties such as retinal image size (C. A. Burbeck, 1987), we wondered whether object size itself might be an important factor. To test this, we needed a task that would tap into the subjective experiences of participants watching a movie on different-sized displays with the same retinal subtense. Our participants used a line bisection task to self-report their level of "presence" (i.e., their involvement with the movie) at several target locations that were probed in a 45-min section of the movie "The Good, The Bad, and The Ugly." Measures of pupil dilation and reaction time to the probes were also obtained. In Experiment 1, we found that subjective ratings of presence increased with physical screen size, supporting our hypothesis. Face scenes also produced higher presence scores than landscape scenes for both screen sizes. In Experiment 2, reaction time and pupil dilation results showed the same trends as the presence ratings and pupil dilation correlated with presence ratings, providing some validation of the method. Overall, the results suggest that real-time measures of subjective presence might be a valuable tool for measuring audience experience for different types of (i) display and (ii) audiovisual material.

The Effects of Compensatory Auditory Stimulation and High-Definition Transcranial Direct Current Stimulation (HD-tDCS) on Tinnitus Perception - A Randomized Pilot Study.

PubMed

Henin, Simon; Fein, Dovid; Smouha, Eric; Parra, Lucas C

2016-01-01

Tinnitus correlates with elevated hearing thresholds and reduced cochlear compression. We hypothesized that reduced peripheral input leads to elevated neuronal gain resulting in the perception of a phantom sound. The purpose of this pilot study was to test whether compensating for this peripheral deficit could reduce the tinnitus percept acutely using customized auditory stimulation. To further enhance the effects of auditory stimulation, this intervention was paired with high-definition transcranial direct current stimulation (HD-tDCS). A randomized sham-controlled, single blind study was conducted in a clinical setting on adult participants with chronic tinnitus (n = 14). Compensatory auditory stimulation (CAS) and HD-tDCS were administered either individually or in combination in order to access the effects of both interventions on tinnitus perception. CAS consisted of sound exposure typical to daily living (20-minute sound-track of a TV show), which was adapted with compressive gain to compensate for deficits in each subject's individual audiograms. Minimum masking levels and the visual analog scale were used to assess the strength of the tinnitus percept immediately before and after the treatment intervention. CAS reduced minimum masking levels, and visual analog scale trended towards improvement. Effects of HD-tDCS could not be resolved with the current sample size. The results of this pilot study suggest that providing tailored auditory stimulation with frequency-specific gain and compression may alleviate tinnitus in a clinical population. Further experimentation with longer interventions is warranted in order to optimize effect sizes.

Small Scale and School Culture: The Experience of Private Schools. ERIC Digest.

ERIC Educational Resources Information Center

Conway, George E.

It is a widely held perception in this country that private schools are superior to public schools. This digest examines school size and school culture as they relate to the high quality of education in private schools. The average private school is about half the size of the average public school. Reflecting Tonnies' (Ferdinand Tonnies, 1887)…

Bigness is in the eye of the beholder. [size and distance perception of pilots in flight

NASA Technical Reports Server (NTRS)

Roscoe, S. N.

1985-01-01

This report reviews an investigation of judgments of size and distance as required of pilots in flight. The experiments covered a broad spectrum of basic psychophysiological issues involving the measurement of visual accommodation and its correlation with various other dependent variables. Psychophysiological issues investigated included the size-distance invariance hypothesis, the projection of afterimages, the moon illusion, night and empty-field myopia, the dark focus and its so-called Mandelbaum effect, the nature and locus of the accommodative stimulus, the relation between accommodation, retinal size, and perceived size, and possible relationships among accommodative responses, autonomic balance, and personality variables.

Replication and Pedagogy in the History of Psychology VI: Egon Brunswik on Perception and Explicit Reasoning

NASA Astrophysics Data System (ADS)

Athy, Jeremy; Friedrich, Jeff; Delany, Eileen

2008-05-01

Egon Brunswik (1903 1955) first made an interesting distinction between perception and explicit reasoning, arguing that perception included quick estimates of an object’s size, nearly always resulting in good approximations in uncertain environments, whereas explicit reasoning, while better at achieving exact estimates, could often fail by wide margins. An experiment conducted by Brunswik to investigate these ideas was never published and the only available information is a figure of the results presented in a posthumous book in 1956. We replicated and extended his study to gain insight into the procedures Brunswik used in obtaining his results. Explicit reasoning resulted in fewer errors, yet more extreme ones than perception. Brunswik’s graphical analysis of the results led to different conclusions, however, than did a modern statistically-based analysis.

Deficit in automatic sound-change detection may underlie some music perception deficits after acute hemispheric stroke.

PubMed

Kohlmetz, C; Altenmüller, E; Schuppert, M; Wieringa, B M; Münte, T F

2001-01-01

Music perception deficits following acute neurological damage are thought to be rare. By a newly devised test battery of music-perception skills, however, we were able to identify among a group of 12 patients with acute hemispheric stroke six patients with music perception deficits (amusia) while six others had no such deficits. In addition we recorded event-related brain potentials (ERPs) in a passive listening task with frequent standard and infrequent pitch deviants designed to elicit the mismatch negativity (MMN). The MMN in the patients with amusia was grossly reduced, while the non-amusic patients and control subjects had MMNs of equal size. These data show that amusia is quite common in unselected stroke patients. The MMN reduction suggests that amusia is related to unspecific automatic stimulus classification deficits in these patients.

How to reinforce perception of depth in single two-dimensional pictures

NASA Technical Reports Server (NTRS)

Nagata, S.

1989-01-01

The physical conditions of the display of single 2-D pictures, which produce images realistically, were studied by using the characteristics of the intake of the information for visual depth perception. Depth sensitivity, which is defined as the ratio of viewing distance to depth discrimination threshold, was introduced in order to evaluate the availability of various cues for depth perception: binocular parallax, motion parallax, accommodation, convergence, size, texture, brightness, and air-perspective contrast. The effects of binocular parallax in different conditions, the depth sensitivity of which is greatest at a distance of up to about 10 m, were studied with the new versatile stereoscopic display. From these results, four conditions to reinforce the perception of depth in single pictures were proposed, and these conditions are met by the old viewing devices and the new high-definition and wide television displays.

The extreme relativity of perception: A new contextual effect modulates human resolving power.

PubMed

Namdar, Gal; Ganel, Tzvi; Algom, Daniel

2016-04-01

The authors report the discovery of a new effect of context that modulates human resolving power with respect to an individual stimulus. They show that the size of the difference threshold or the just noticeable difference around a standard stimulus depends on the range of the other standards tested simultaneously for resolution within the same experimental session. The larger this range, the poorer the resolving power for a given standard. The authors term this effect the range of standards effect (RSE). They establish this result both in the visual domain for the perception of linear extent, and in the somatosensory domain for the perception of weight. They discuss the contingent nature of stimulus resolution in perception and psychophysics and contrast it with the immunity to contextual influences of visually guided action. (c) 2016 APA, all rights reserved).

Morphological evidence of mechanoreceptive gravity perception in a water flea - Daphnia magna

NASA Technical Reports Server (NTRS)

Meyers, D. G.

1985-01-01

Hair-like structures or setae located in the basal membrane of the swimming antennae of the water flea, D. magna, were observed by scanning electron microscopy and compared to mechanoreceptors in the Higher Order Crustacea. Similarities in anatomy, size, attachment, number, length, and orientation support the hypothesis that the setae are rheoceptive mechanoreceptors which mediate gravity perception through deflection by water currents during the sink phase of hop-and-sink swimming behavior.

Quantifying the strength of the associations of prototype perceptions with behaviour, behavioural willingness and intentions: a meta-analysis.

PubMed

van Lettow, Britt; de Vries, Hein; Burdorf, Alex; van Empelen, Pepijn

2016-01-01

Prototypes (i.e., social images representing perceptions of typical persons engaging in or refraining from certain behaviour) have been shown to explain health-related behaviours. The present meta-analysis quantified the strength of the associations of prototype perceptions with health motivation and behaviour. Specifically, the analysis addressed (i) the relationship of prototype favourability (i.e., degree of likability) and similarity (i.e., perceived resemblance to the self) with behaviour, willingness and intentions; (ii) the effect of the interaction between favourability and similarity; and (iii) the extent to which health-risk and health-protective prototypes differed in their association with these outcomes. A total of 80 independent studies were identified based on 69 articles. The results indicated that prototype favourability and similarity were related to behaviour, intentions and willingness with small-to-medium effect sizes (r+ = 0.12-0.43). Direct measures of prototype perceptions generally produced larger effects than indirect measures. The interaction between favourability and similarity produced small-to-large effect sizes (r+ = .22-.54). The results suggest that both health-risk and health-protective prototypes might be useful targets for interventions (r+ = .22-.54). In order to increase health-protective behaviours, intentions and behaviour could be targeted by increasing similarity to health-protective prototypes. Health-risk behaviour might be decreased by targeting willingness by modifying health-risk prototype favourability and similarity.

Influence of urbanity on perception of mental illness stigma: a population based study in urban and rural Hanoi, Vietnam.

PubMed

Ta, Thi Minh Tam; Zieger, Aron; Schomerus, Georg; Cao, Tien Duc; Dettling, Michael; Do, Xuan Tinh; Mungee, Aditya; Diefenbacher, Albert; Angermeyer, Matthias C; Hahn, Eric

2016-12-01

To examine, for the first time in Vietnam, whether urbanity of respondents among other socio-demographic factors affects the public perception of stigma attached to persons with mental illness in Hanoi. A general population-based survey was carried out in 2013 in the greater Hanoi area. The perception of stigma attached to people with mental illness was elicited using Link's perceived discrimination and devaluation scale (PDDS) carried out in Vietnamese language. The survey sample (n = 806) was stratified for gender, urban/rural location, age, household size and marital status, in accordance with the 2013 Vietnamese census. Comparing the total score of the PDDS and its single items, we found less perceived stigma and discrimination among the rural population of Hanoi and in respondents who reported religious attainment to either Buddhism or Christianity. Logistic regression analyses found no significant influences of gender, age, household size or marital status regarding the perceived stigma toward persons with mental illness. Less negative perception of stigma attached to persons with mental illness that was observed among the rural population in the Hanoi area may be interpreted in the light of possibly more demanding living conditions in modern urban Vietnam with less opportunities for mentally ill patients and points toward a dynamic interaction with rapidly changing living conditions in Asian megacities. © The Author(s) 2016.

Scanpath-based analysis of objects conspicuity in context of human vision physiology.

PubMed

Augustyniak, Piotr

2007-01-01

This paper discusses principal aspects of objects conspicuity investigated with use of an eye tracker and interpreted on the background of human vision physiology. Proper management of objects conspicuity is fundamental in several leading edge applications in the information society like advertisement, web design, man-machine interfacing and ergonomics. Although some common rules of human perception are applied since centuries in the art, the interest of human perception process is motivated today by the need of gather and maintain the recipient attention by putting selected messages in front of the others. Our research uses the visual tasks methodology and series of progressively modified natural images. The modifying details were attributed by their size, color and position while the scanpath-derived gaze points confirmed or not the act of perception. The statistical analysis yielded the probability of detail perception and correlations with the attributes. This probability conforms to the knowledge about the retina anatomy and perception physiology, although we use noninvasive methods only.

Dairy farmers with larger herd sizes adopt more precision dairy technologies.

PubMed

Gargiulo, J I; Eastwood, C R; Garcia, S C; Lyons, N A

2018-06-01

An increase in the average herd size on Australian dairy farms has also increased the labor and animal management pressure on farmers, thus potentially encouraging the adoption of precision technologies for enhanced management control. A survey was undertaken in 2015 in Australia to identify the relationship between herd size, current precision technology adoption, and perception of the future of precision technologies. Additionally, differences between farmers and service providers in relation to perception of future precision technology adoption were also investigated. Responses from 199 dairy farmers, and 102 service providers, were collected between May and August 2015 via an anonymous Internet-based questionnaire. Of the 199 dairy farmer responses, 10.4% corresponded to farms that had fewer than 150 cows, 37.7% had 151 to 300 cows, 35.5% had 301 to 500 cows; 6.0% had 501 to 700 cows, and 10.4% had more than 701 cows. The results showed that farmers with more than 500 cows adopted between 2 and 5 times more specific precision technologies, such as automatic cup removers, automatic milk plant wash systems, electronic cow identification systems and herd management software, when compared with smaller farms. Only minor differences were detected in perception of the future of precision technologies between either herd size or farmers and service providers. In particular, service providers expected a higher adoption of automatic milking and walk over weighing systems than farmers. Currently, the adoption of precision technology has mostly been of the type that reduces labor needs; however, respondents indicated that by 2025 adoption of data capturing technology for monitoring farm system parameters would be increased. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

[Effect sizes, statistical power and sample sizes in "the Japanese Journal of Psychology"].

PubMed

Suzukawa, Yumi; Toyoda, Hideki

2012-04-01

This study analyzed the statistical power of research studies published in the "Japanese Journal of Psychology" in 2008 and 2009. Sample effect sizes and sample statistical powers were calculated for each statistical test and analyzed with respect to the analytical methods and the fields of the studies. The results show that in the fields like perception, cognition or learning, the effect sizes were relatively large, although the sample sizes were small. At the same time, because of the small sample sizes, some meaningful effects could not be detected. In the other fields, because of the large sample sizes, meaningless effects could be detected. This implies that researchers who could not get large enough effect sizes would use larger samples to obtain significant results.

Physical perceptions and self-concept in athletes with muscle dysmorphia symptoms.

PubMed

González-Martí, Irene; Fernández Bustos, Juan Gregorio; Hernández-Martínez, Andrea; Contreras Jordán, Onofre Ricardo

2014-01-01

Individuals affected by Muscle Dysmorphia (MD; body image disorder based on the sub estimation of muscle size), practice weightlifting in order to alleviate their muscular dissatisfaction. Although physical activity is associated with increased physical self-perception, we assume that this was not reproduced in full in people with MD. The study sample consisted of 734 weightlifters and bodybuilders, 562 men and 172 women, who completed the Escala de Satisfacción Muscular, the Physical Self-Concept Questionnaire, and from whom measures of body fat and Fat -Free Mass Index (FFMI) were obtained. The results showed that people suffering from MD symptoms, overall, have poorer physical self-concept perceptions (F = 18.46 - 34.77, p < .01).

Ballroom dance and body size perception.

PubMed

Fonseca, Cristiane Costa; Thurm, Bianca Elisabeth; Vecchi, Rodrigo Luiz; Gama, Eliane Florencio

2014-10-01

Ballroom dancing consists in the performance of rhythmic movements guided by music, which provide sensorimotor integration and stimulate feelings. The body schema is the unconscious sensorimotor representation that allows the individual to perceive his anatomical body in space. Comprising tactile, proprioceptive, kinesthetic, and environmental information, it is directly related to movement. The aim of this study was to investigate the influence of non-competitive practice of ballroom dancing on body perception. The projection point test was applied to 30 volunteers before and after a period of 3 mo.; 15 controls attended lectures on body perception and 15 participants took dance lessons. It was observed that ballroom dancing brought perceptual benefits for those who practiced it.

Voices from the Field: The Perceptions of Teachers and Principals on the Class Size Reduction Program in a Large Urban School District.

ERIC Educational Resources Information Center

Munoz, Marco A.; Portes, Pedro R.

A class size reduction (CSR) program was implemented in a large low-performing urban elementary school district. The CSR program helps schools improve student learning by hiring additional teachers so that children in the early elementary grades can attend smaller classes. This study used a participant-oriented evaluation model to examine the…

The influence of herd size, conspecific risk, and predation risk on the vigilance of elk (Cervus elaphus) in Yellowstone National Park, and, Interest, learning, and a thematic biology course

NASA Astrophysics Data System (ADS)

Lung, Mark A.

This dissertation is a composite of biological and educational research. The biological research concerns Rocky Mountain elk (Cervus elaphus ) behavior. The educational research presents ideas and findings on the influence of a thematic general biology course on student interest and perception of learning. The dissertation begins with a Preface that attempts to bring the ideas presented in later chapters together. Chapter One is a review of the literature concerning sociality, social behaviors, and elk biology. It summarizes current research literature as a means of introduction to Chapter Two. Chapter Two presents findings concerning the effects of herd size, predation risk, and the risk of being near conspecifics on two behaviors commonly associated with social animals---vigilance and aggression. Vigilance and aggression were measured in elk in Yellowstone National Park in two regions that varied in their presence of elk predators (wolves---Canis lupus, and grizzly bears---Ursus arctos) and in two seasons (spring and fall) that varied in the risks of being near conspecifics. Overall, male and female elk responded very differently. Male elk adjust their vigilance and aggression in response to changes in conspecific risk, but not to changes in predation risk. Female elk adjust their vigilance in response to changes in predation risk, but not to changes in conspecific risk. Males show no response in vigilance to changes in herd size. Non-reproductive females, however, adjust their levels of vigilance with changes in herd size in high risk regions. Interestingly, in the spring, vigilance decreases with increasing herd size, but in the fall, vigilance increases with increasing herd size. Chapter Three presents findings concerning the influence of a thematic course design on student perceptions of interest and teaming in a non-major's biology course (Bins 100: Concepts of Biology). I compared responses on student evaluations from two sections of Bios 100 taught in a traditional, survey style with a section taught using a thematic approach. Students in the thematic section responded significantly more positively in all responses concerning the effect of the course on interest and perception of learning.

Perception while watching movies: Effects of physical screen size and scene type

PubMed Central

Troscianko, Tom; Meese, Timothy S.; Hinde, Stephen

2012-01-01

Over the last decade, television screens and display monitors have increased in size considerably, but has this improved our televisual experience? Our working hypothesis was that the audiences adopt a general strategy that “bigger is better.” However, as our visual perceptions do not tap directly into basic retinal image properties such as retinal image size (C. A. Burbeck, 1987), we wondered whether object size itself might be an important factor. To test this, we needed a task that would tap into the subjective experiences of participants watching a movie on different-sized displays with the same retinal subtense. Our participants used a line bisection task to self-report their level of “presence” (i.e., their involvement with the movie) at several target locations that were probed in a 45-min section of the movie “The Good, The Bad, and The Ugly.” Measures of pupil dilation and reaction time to the probes were also obtained. In Experiment 1, we found that subjective ratings of presence increased with physical screen size, supporting our hypothesis. Face scenes also produced higher presence scores than landscape scenes for both screen sizes. In Experiment 2, reaction time and pupil dilation results showed the same trends as the presence ratings and pupil dilation correlated with presence ratings, providing some validation of the method. Overall, the results suggest that real-time measures of subjective presence might be a valuable tool for measuring audience experience for different types of (i) display and (ii) audiovisual material. PMID:23145293

An Evaluation of the Effectiveness of a Vibrating Syringe Attachment in Decreasing Intraoral Injection Pain Perception

DTIC Science & Technology

2012-06-01

mucosa penetrations to periosteum by a 27-gauge short needle attached to a dental cartridge syringe . New needles were used for each injection, and the...of the American Dental Association, 134(2), 228-234. 7. Bonjar AHS. (2011) Syringe micro vibrator (SMV) a new device being introduced in dentistry...Lautenbacher S. (2004) Pathophysiology of Pain Perception. New York , New York : Kluwer and Plenum. 16 Flanagan T, Wahl MJ, Schmitt MM, Wahl JA. (2007) Size

Unit-level voluntary turnover rates and customer service quality: implications of group cohesiveness, newcomer concentration, and size.

PubMed

Hausknecht, John P; Trevor, Charlie O; Howard, Michael J

2009-07-01

Despite substantial growth in the service industry and emerging work on turnover consequences, little research examines how unit-level turnover rates affect essential customer-related outcomes. The authors propose an operational disruption framework to explain why voluntary turnover impairs customers' service quality perceptions. On the basis of a sample of 75 work units and data from 5,631 employee surveys, 59,602 customer surveys, and organizational records, results indicate that unit-level voluntary turnover rates are negatively related to service quality perceptions. The authors also examine potential boundary conditions related to the disruption framework. Of 3 moderators studied (group cohesiveness, group size, and newcomer concentration), results show that turnover's negative effects on service quality are more pronounced in larger units and in those with a greater concentration of newcomers.

The integration of stimulus dimensions in the perception of music.

PubMed

Prince, Jon B

2011-11-01

A central aim of cognitive psychology is to explain how we integrate stimulus dimensions into a unified percept, but how the dimensions of pitch and time combine in the perception of music remains a largely unresolved issue. The goal of this study was to test the effect of varying the degree of conformity to dimensional structure in pitch and time (specifically, tonality and metre) on goodness ratings and classifications of melodies. The pitches and durations of melodies were either presented in their original order, as a reordered sequence, or replaced with random elements. Musically trained and untrained participants (24 each) rated melodic goodness, attending selectively to the dimensions of pitch, time, or both. Also, 24 trained participants classified whether or not the melodies were tonal, metric, or both. Pitch and temporal manipulations always influenced responses, but participants successfully emphasized either dimension in accordance with instructions. Effects of pitch and time were mostly independent for selective attention conditions, but more interactive when evaluating both dimensions. When interactions occurred, the effect of either dimension increased as the other dimension conformed more to its original structure. Relative main effect sizes (| pitch η(2) - time η(2) |) predicted the strength of pitch-time interactions (pitch × time η(2)); interactions were stronger when main effect sizes were more evenly matched. These results have implications for dimensional integration in several domains. Relative main effect size could serve as an indicator of dimensional salience, such that interactions are more likely when dimensions are equally salient.

Explaining the moon illusion

PubMed Central

Kaufman, Lloyd; Kaufman, James H.

2000-01-01

An old explanation of the moon illusion holds that various cues place the horizon moon at an effectively greater distance than the elevated moon. Although both moons have the same angular size, the horizon moon must be perceived as larger. More recent explanations hold that differences in accommodation or other factors cause the elevated moon to appear smaller. As a result of this illusory difference in size, the elevated moon appears to be more distant than the horizon moon. These two explanations, both based on the geometry of stereopsis, lead to two diametrically opposed hypotheses. That is, a depth interval at a long distance is associated with a smaller binocular disparity, whereas an equal depth interval at a smaller distance is associated with a larger disparity. We conducted experiments involving artificial moons and confirmed the hypothesis that the horizon moon is at a greater perceptual distance. Moreover, when a moon of constant angular size was moved closer it was also perceived as growing smaller, which is consistent with the older explanation. Although Emmert's law does not predict the size–distance relationship over long distances, we conclude that the horizon moon is perceived as larger because the perceptual system treats it as though it is much farther away. Finally, we observe that recent explanations substitute perceived size for angular size as a cue to distance. Thus, they imply that perceptions cause perceptions. PMID:10618447

Odors Bias Time Perception in Visual and Auditory Modalities

PubMed Central

Yue, Zhenzhu; Gao, Tianyu; Chen, Lihan; Wu, Jiashuang

2016-01-01

Previous studies have shown that emotional states alter our perception of time. However, attention, which is modulated by a number of factors, such as emotional events, also influences time perception. To exclude potential attentional effects associated with emotional events, various types of odors (inducing different levels of emotional arousal) were used to explore whether olfactory events modulated time perception differently in visual and auditory modalities. Participants were shown either a visual dot or heard a continuous tone for 1000 or 4000 ms while they were exposed to odors of jasmine, lavender, or garlic. Participants then reproduced the temporal durations of the preceding visual or auditory stimuli by pressing the spacebar twice. Their reproduced durations were compared to those in the control condition (without odor). The results showed that participants produced significantly longer time intervals in the lavender condition than in the jasmine or garlic conditions. The overall influence of odor on time perception was equivalent for both visual and auditory modalities. The analysis of the interaction effect showed that participants produced longer durations than the actual duration in the short interval condition, but they produced shorter durations in the long interval condition. The effect sizes were larger for the auditory modality than those for the visual modality. Moreover, by comparing performance across the initial and the final blocks of the experiment, we found odor adaptation effects were mainly manifested as longer reproductions for the short time interval later in the adaptation phase, and there was a larger effect size in the auditory modality. In summary, the present results indicate that odors imposed differential impacts on reproduced time durations, and they were constrained by different sensory modalities, valence of the emotional events, and target durations. Biases in time perception could be accounted for by a framework of attentional deployment between the inducers (odors) and emotionally neutral stimuli (visual dots and sound beeps). PMID:27148143

Polyphenolic, polysaccharide and oligosaccharide composition of Tempranillo red wines and their relationship with the perceived astringency.

PubMed

Quijada-Morín, Natalia; Williams, Pascale; Rivas-Gonzalo, Julián C; Doco, Thierry; Escribano-Bailón, M Teresa

2014-07-01

The influence of the proanthocyanidic, polysaccharide and oligosaccharide composition on astringency perception of Tempranillo wines has been evaluated. Statistical analyses revealed the existence of relationships between chemical composition and perceived astringency. Proanthocyanidic subunit distribution had the strongest contribution to the multiple linear regression (MLR) model. Polysaccharide families showed clear opposition to astringency perception according to principal component analysis (PCA) results, being stronger for mannoproteins and rhamnogalacturonan-II (RG-II), but only Polysaccharides Rich in Arabinose and Galactose (PRAGs) were considered in the final fitted MLR model, which explained 96.8% of the variability observed in the data. Oligosaccharides did not show a clear opposition, revealing that structure and size of carbohydrates are important for astringency perception. Mannose and galactose residues in the oligosaccharide fraction are positively related to astringency perception, probably because its presence is consequence of the degradation of polysaccharides. Copyright © 2014 Elsevier Ltd. All rights reserved.

Body ownership promotes visual awareness.

PubMed

van der Hoort, Björn; Reingardt, Maria; Ehrsson, H Henrik

2017-08-17

The sense of ownership of one's body is important for survival, e.g., in defending the body against a threat. However, in addition to affecting behavior, it also affects perception of the world. In the case of visuospatial perception, it has been shown that the sense of ownership causes external space to be perceptually scaled according to the size of the body. Here, we investigated the effect of ownership on another fundamental aspect of visual perception: visual awareness. In two binocular rivalry experiments, we manipulated the sense of ownership of a stranger's hand through visuotactile stimulation while that hand was one of the rival stimuli. The results show that ownership, but not mere visuotactile stimulation, increases the dominance of the hand percept. This effect is due to a combination of longer perceptual dominance durations and shorter suppression durations. Together, these results suggest that the sense of body ownership promotes visual awareness.

Body ownership promotes visual awareness

PubMed Central

Reingardt, Maria; Ehrsson, H Henrik

2017-01-01

The sense of ownership of one’s body is important for survival, e.g., in defending the body against a threat. However, in addition to affecting behavior, it also affects perception of the world. In the case of visuospatial perception, it has been shown that the sense of ownership causes external space to be perceptually scaled according to the size of the body. Here, we investigated the effect of ownership on another fundamental aspect of visual perception: visual awareness. In two binocular rivalry experiments, we manipulated the sense of ownership of a stranger’s hand through visuotactile stimulation while that hand was one of the rival stimuli. The results show that ownership, but not mere visuotactile stimulation, increases the dominance of the hand percept. This effect is due to a combination of longer perceptual dominance durations and shorter suppression durations. Together, these results suggest that the sense of body ownership promotes visual awareness. PMID:28826500

Multimodal emotion perception after anterior temporal lobectomy (ATL)

PubMed Central

Milesi, Valérie; Cekic, Sezen; Péron, Julie; Frühholz, Sascha; Cristinzio, Chiara; Seeck, Margitta; Grandjean, Didier

2014-01-01

In the context of emotion information processing, several studies have demonstrated the involvement of the amygdala in emotion perception, for unimodal and multimodal stimuli. However, it seems that not only the amygdala, but several regions around it, may also play a major role in multimodal emotional integration. In order to investigate the contribution of these regions to multimodal emotion perception, five patients who had undergone unilateral anterior temporal lobe resection were exposed to both unimodal (vocal or visual) and audiovisual emotional and neutral stimuli. In a classic paradigm, participants were asked to rate the emotional intensity of angry, fearful, joyful, and neutral stimuli on visual analog scales. Compared with matched controls, patients exhibited impaired categorization of joyful expressions, whether the stimuli were auditory, visual, or audiovisual. Patients confused joyful faces with neutral faces, and joyful prosody with surprise. In the case of fear, unlike matched controls, patients provided lower intensity ratings for visual stimuli than for vocal and audiovisual ones. Fearful faces were frequently confused with surprised ones. When we controlled for lesion size, we no longer observed any overall difference between patients and controls in their ratings of emotional intensity on the target scales. Lesion size had the greatest effect on intensity perceptions and accuracy in the visual modality, irrespective of the type of emotion. These new findings suggest that a damaged amygdala, or a disrupted bundle between the amygdala and the ventral part of the occipital lobe, has a greater impact on emotion perception in the visual modality than it does in either the vocal or audiovisual one. We can surmise that patients are able to use the auditory information contained in multimodal stimuli to compensate for difficulty processing visually conveyed emotion. PMID:24839437

A brief psychological intervention for mothers of children with food allergy can change risk perception and reduce anxiety: Outcomes of a randomized controlled trial.

PubMed

Boyle, R J; Umasunthar, T; Smith, J G; Hanna, H; Procktor, A; Phillips, K; Pinto, C; Gore, C; Cox, H E; Warner, J O; Vickers, B; Hodes, M

2017-10-01

Mothers of children with food allergy have increased anxiety, which may be influenced by healthcare professionals' communication of risk. To evaluate a brief psychological intervention for reducing anxiety in mothers of children with food allergy. Two hundred mothers of children with food allergy were recruited from allergy clinics. A computer-generated randomization list was used to allocate participants to a single-session cognitive behavioural therapy intervention including a risk communication module, or standard care. Anxiety and risk perception were assessed at 6 weeks and 1 year. Primary outcome was state anxiety at 6 weeks. Secondary outcomes included state anxiety at 1 year, risk perception at 6 weeks and 1 year, and salivary cortisol response to a simulated anaphylaxis scenario at 1 year. We found no significant difference in the primary outcome state anxiety at 6 weeks, with mean 31.9 (SD 10.2) intervention, 34.0 (10.2) control; mean difference 2.1 (95% CI -0.9, 5.0; P=.17). There was significantly reduced state anxiety at 6 weeks in the intervention group, in the subgroup of participants with moderate/high anxiety at enrolment (103/200, 52%), with mean 33.0 (SD 9.3) intervention, 37.8 (SD 10.0) control; mean difference 4.8 (95% CI 0.9, 8.7; P=.016; Cohen's d effect size 0.50). The psychological intervention also reduced risk perception and salivary cortisol response (P=.032; effect size 0.36). We found evidence that a brief psychological intervention which incorporates accurate risk information may impact on anxiety, risk perception and physiological stress response in mothers of children with food allergy. © 2017 John Wiley & Sons Ltd.

The nature of face representations in subcortical regions.

PubMed

Gabay, Shai; Burlingham, Charles; Behrmann, Marlene

2014-07-01

Studies examining the neural correlates of face perception in humans have focused almost exclusively on the distributed cortical network of face-selective regions. Recently, however, investigations have also identified subcortical correlates of face perception and the question addressed here concerns the nature of these subcortical face representations. To explore this issue, we presented to participants pairs of images sequentially to the same or to different eyes. Superior performance in the former over latter condition implicates monocular, prestriate portions of the visual system. Over a series of five experiments, we manipulated both lower-level (size, location) as well as higher-level (identity) similarity across the pair of faces. A monocular advantage was observed even when the faces in a pair differed in location and in size, implicating some subcortical invariance across lower-level image properties. A monocular advantage was also observed when the faces in a pair were two different images of the same individual, indicating the engagement of subcortical representations in more abstract, higher-level aspects of face processing. We conclude that subcortical structures of the visual system are involved, perhaps interactively, in multiple aspects of face perception, and not simply in deriving initial coarse representations. Copyright © 2014 Elsevier Ltd. All rights reserved.

Breakfast food health and acute exercise: Effects on state body image.

PubMed

Hayes, Jacqueline F; Giles, Grace E; Mahoney, Caroline R; Kanarek, Robin B

2018-05-10

Food intake and exercise have been shown to alter body satisfaction in a state-dependent manner. One-time consumption of food perceived as unhealthy can be detrimental to body satisfaction, whereas an acute bout of moderate-intensity aerobic exercise can be beneficial. The current study examined the effect of exercise on state body image and appearance-related self-esteem following consumption of isocaloric foods perceived as healthy or unhealthy in 36 female college students (18-30 years old) in the Northeastern United States. Using a randomized-controlled design, participants attended six study sessions with breakfast conditions (healthy, unhealthy, no food) and activity (exercise, quiet rest) as within-participants factors. Body image questionnaires were completed prior to breakfast condition, between breakfast and activity conditions, and following activity condition. Results showed that consumption of an unhealthy breakfast decreased appearance self-esteem and increased body size perception, whereas consumption of a healthy breakfast did not influence appearance self-esteem but increased body size perception. Exercise did not influence state body image attitudes or perceptions following meal consumption. Study findings suggest that morning meal type, but not aerobic exercise, influence body satisfaction in college-aged females. Copyright © 2018. Published by Elsevier Ltd.

Chubby hands or little fingers: sex differences in hand representation.

PubMed

Coelho, Lara A; Gonzalez, Claudia L R

2018-04-03

Disturbed body representation is a condition defined by the perception that one's body size is different from their anatomical size. While equal amounts of males and females suffer from disturbed body representation, there appear to be differences in the direction of this distortion. Females will typically overestimate, whereas males will typically underestimate body size. One part of the body that has been consistently misperceived is the hands. This misrepresentation consists of two distinct characteristics: an overestimation of hand width, and an underestimation of finger length. Many of these studies, however, have used predominately female participants, allowing for the possibility that women are driving this distortion. The aim of the present study was to examine possible sex differences in hand perception. To this end, participants estimated the location of ten landmarks on their hands when their hands were hidden from view. Our results indicate that females follow the characteristic distortion, whereas males only underestimate finger length (albeit more than females). These findings are surprising, because the hands are not an area of concern for weight gain/loss. We discuss these findings in relation to body dysmorphia literature.

Serotonin has opposite effects on the aggressiveness of crayfish, facing either a smaller or a larger rival: alteration of size perception.

PubMed

Bacqué-Cazenave, Julien; Cattaert, Daniel; Delbecque, Jean Paul; Fossat, Pascal

2018-04-26

We injected serotonin (5-HT) in adult male crayfish before pairing them with size-matched non-injected competitors, and we observed dyadic agonistic interactions. Paradoxically, 5-HT elicited opposite behavioral responses if the injected animal was opposed by a smaller or larger rival: the level of aggressiveness of the injected crayfish was higher in front of a larger rival but lower in front of a smaller rival. Our results indicate that the effects of 5-HT on aggressiveness are dependent on the perception of the relative size difference of the opponent. In both cases, however, 5-HT significantly delayed the decision to retreat. We conclude that 5-HT does not primarily act on aggressiveness but rather on the brain centers that integrate risk assessment and/or decision-making, which then modulate the aggressive response. Our study supports a reinterpretation of the role of 5-HT in crustacean agonistic behavior that may be of interest for other animals. © 2018. Published by The Company of Biologists Ltd.

Perceiving groups: The people perception of diversity and hierarchy.

PubMed

Phillips, L Taylor; Slepian, Michael L; Hughes, Brent L

2018-05-01

The visual perception of individuals has received considerable attention (visual person perception), but little social psychological work has examined the processes underlying the visual perception of groups of people (visual people perception). Ensemble-coding is a visual mechanism that automatically extracts summary statistics (e.g., average size) of lower-level sets of stimuli (e.g., geometric figures), and also extends to the visual perception of groups of faces. Here, we consider whether ensemble-coding supports people perception, allowing individuals to form rapid, accurate impressions about groups of people. Across nine studies, we demonstrate that people visually extract high-level properties (e.g., diversity, hierarchy) that are unique to social groups, as opposed to individual persons. Observers rapidly and accurately perceived group diversity and hierarchy, or variance across race, gender, and dominance (Studies 1-3). Further, results persist when observers are given very short display times, backward pattern masks, color- and contrast-controlled stimuli, and absolute versus relative response options (Studies 4a-7b), suggesting robust effects supported specifically by ensemble-coding mechanisms. Together, we show that humans can rapidly and accurately perceive not only individual persons, but also emergent social information unique to groups of people. These people perception findings demonstrate the importance of visual processes for enabling people to perceive social groups and behave effectively in group-based social interactions. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

How hard they hit? Perception, adaptation and public health implications of heat waves in urban and peri-urban Pakistan.

PubMed

Rauf, Sara; Bakhsh, Khuda; Abbas, Azhar; Hassan, Sarfraz; Ali, Asghar; Kächele, Harald

2017-04-01

Heat waves threaten human health given the fast changing climatic scenarios in the recent past. Adaptation to heat waves would take place when people perceive their impacts based on their knowledge. The present study examines perception level and its determinants resulting in adaptation to heat waves in Pakistan. The study used cross-sectional data from urban and peri-urban respondents of Faisalabad District. The study employs a health belief model to assess risk perception among the respondents. Logistic model is used to determine factors affecting level of knowledge, perception and adaptation to heat waves. Around 30% of peri-urban respondents have a low level of knowledge about the fatal impacts of heat waves. Risk perception of heat waves is very low among urban (57%) and peri-urban (66%) respondents. Households' knowledge on heat waves is significantly related to age, gender, education, wealth and access to health services. Determinants of perception include knowledge of heat waves, age and joint effect of marital status and knowledge while income level, family size, urban/peri-urban background, perceived barriers, perceived benefits and cues to action significantly affect adaptation to heat waves. To reduce deadly health impacts, mass awareness campaigns are needed to build perception and improve adaptation to heat waves.

A homogeneous field for light adaptation.

DOT National Transportation Integrated Search

1966-09-01

Visual judgments of size, distance, slant, etc. in the flying situation are often made under reduced cue conditions, especially during night flying. In the experimental study of spatial perception under these conditions, experiments often require lon...

Managerial Receptivity and Implementation of Policies.

ERIC Educational Resources Information Center

Stevens, John M.; And Others

1980-01-01

Managerial receptivity to new policy, perceived emphasis by top level management, organizational size, work overload, perceptions of the importance of performance for promotion, and the manager's attitude toward change were important predictors for successful implementation. (Author)

Illusion in reality: visual perception in displays

NASA Astrophysics Data System (ADS)

Kaufman, Lloyd; Kaufman, James H.

2001-06-01

Research into visual perception ultimately affects display design. Advance in display technology affects, in turn, our study of perception. Although this statement is too general to provide controversy, this paper present a real-life example that may prompt display engineers to make greater use of basic knowledge of visual perception, and encourage those who study perception to track more closely leading edge display technology. Our real-life example deals with an ancient problem, the moon illusion: why does the horizon moon appear so large while the elevated moon look so small. This was a puzzle for many centuries. Physical explanations, such as refraction by the atmosphere, are incorrect. The difference in apparent size may be classified as a misperception, so the answer must lie in the general principles of visual perception. The factors underlying the moon illusion must be the same factors as those that enable us to perceive the sizes of ordinary objects in visual space. Progress toward solving the problem has been irregular, since methods for actually measuring the illusion under a wide range of conditions were lacking. An advance in display technology made possible a serious and methodologically controlled study of the illusion. This technology was the first heads-up display. In this paper we will describe how the heads-up display concept made it possible to test several competing theories of the moon illusion, and how it led to an explanation that stood for nearly 40 years. We also consider the criticisms of that explanation and how the optics of the heads-up display also played a role in providing data for the critics. Finally, we will describe our own advance on the original methodology. This advance was motivated by previously unrelated principles of space perception. We used a stereoscopic heads up display to test alternative hypothesis about the illusion and to discrimate between two classes of mutually contradictory theories. At its core, the explanation for the moon illusion has implications for the design of virtual reality displays. Howe do we scale disparity at great distances to reflect depth between points at those distances. We conjecture that one yardstick involved in that scaling is provided by oculomotor cues operating at near distances. Without the presence of such a yardstick it is not possible to account for depth at long distances. As we shall explain, size and depth constancy should both fail in virtual reality display where all of the visual information is optically in one plane. We suggest ways to study this problem, and also means by which displays may be designed to present information at different optical distances.

Law enforcement officers' risk perceptions toward on-duty motor-vehicle events.

PubMed

Tiesman, Hope M; Heick, Rebecca J; Konda, Srinivas; Hendricks, Scott

Motor-vehicle-related events (MVEs) are the leading cause of on-duty death for law enforcement officers, yet little is known about how officers view this significant job hazard. The purpose of this paper is to explore officers' motor-vehicle risk perception and examine how prior on-duty MVEs and the death or injury of a fellow officer influences this perception. A state-wide random sample of 136 law enforcement agencies was drawn using publically accessible databases, stratified on type and size of agency. In total, 60 agencies agreed to participate and a cross-sectional questionnaire was distributed to 1,466 officers. Using six-point Likert scales, composite scores for motor-vehicle and intentional violence risk perception were derived. A linear regression multivariable model was used to examine factors affecting motor-vehicle risk perception. Motor-vehicle risk perception scores were significantly higher than intentional violence scores. A prior on-duty motor-vehicle crash, prior roadside incident, or knowledge of fellow officer's injury or death from a MVE significantly increased motor-vehicle risk perception scores. After controlling for potential confounders though, only prior on-duty crashes and roadside incidents impacted motor-vehicle risk perception. The study comprised primarily small, rural agencies and generalizability may be limited. Also, although the data were collected anonymously, reporting and response biases may affect these findings. This study involved a large and diverse cohort of officers and explored motor-vehicle risk perception. A better understanding of officers' risk perceptions will assist in the development and implementation of occupational injury prevention programs, training, and policy.

Reducing Size, Weight, and Power (SWaP) of Perception Systems in Small Autonomous Aerial Systems

NASA Technical Reports Server (NTRS)

Jones, Kennie H.; Gross, Jason

2014-01-01

The objectives are to examine recent trends in the reduction of size, weight, and power (SWaP) requirements of sensor systems for environmental perception and to explore new technology that may overcome limitations in current systems. Improving perception systems to facilitate situation awareness is critical in the move to introduce increasing autonomy in aerial systems. Whether the autonomy is in the current state-of-the-art of increasing automation or is enabling cognitive decisions that facilitate adaptive behavior, collection of environmental information and fusion of that information into knowledge that can direct actuation is imperative to decisions resulting in appropriate behavior. Artificial sensory systems such as cameras, radar, LIDAR, and acoustic sensors have been in use on aircraft for many years but, due to the large size and weight of the airplane and electrical power made available through powerful engines, the SWaP requirements of these sensors was inconsequential. With the proliferation of Remote Piloted Vehicles (RPV), the trend is in significant reduction in SWaP of the vehicles. This requires at least an equivalent reduction in SWaP for the sensory systems. A survey of some currently available sensor systems and changing technology will reveal the trend toward reduction of SWaP of these systems and will predict future reductions. A new technology will be introduced that provides an example of a desirable new trend. A new device replaces multiple conventional sensory devices facilitating synchronization, localization, altimetry, collision avoidance, terrain mapping, and data communication in a single integrated, small form-factor, extremely lightweight, and low power device that it is practical for integration into small autonomous vehicles and can facilitate cooperative behavior. The technology is based on Ultra WideBand (UWB) radio using short pulses of energy rather than continuous sine waves. The characteristics of UWB yield several desirable characteristics to facilitate integration of perception for autonomous activities. The capabilities of this device and its limitations will be assessed.

Perceptions of non-traditional tobacco products between asthmatic and non-asthmatic college students.

PubMed

Martinasek, Mary P; White, Robin M; Wheldon, Christopher W; Gibson-Young, Linda

2018-05-01

Electronic nicotine delivery systems (ENDS) use is common among college students and there are perceptions that ENDS are not as harmful as traditional cigarettes. The aim of this study was to examine differences in ENDS use, risk perceptions and co-occurring smoking behaviors between college students with and without asthma. The study consisted of a cross-sectional online survey with a final sample size of 898 college students. The voluntary participation survey was disseminated to all undergraduate and graduate students at a mid-sized liberal arts university in the Southeast U.S. in the fall of 2014. Approximately 19.7% reported that they had been previously diagnosed with asthma. Forty three percent of participants (n = 384) used ENDS in the past 30 days. Equivalent percentages of college students with asthma (46.9%) and college students without asthma (46.9%) have tried ENDS. Overall participants indicated that they perceived ENDS use as less (44%) or equally (38%) as harmful as cigarettes. College students with asthma had 2.85 (95% CI: 1.18-6.89) greater odds of being in the poly user class, which was characterized by dual use of ENDS, combustible cigarettes, hookah, and marijuana. In this study, college students with asthma were similar to their peers with regard to their use of ENDS and related risk perceptions; however, a small subsample of those with asthma exhibited problematic smoking behaviors characterized by dual use of multiple tobacco products including marijuana.

Acceptability of Dry Dog Food Visual Characteristics by Consumer Segments Based on Overall Liking: a Case Study in Poland.

PubMed

Gomez Baquero, David; Koppel, Kadri; Chambers, Delores; Hołda, Karolina; Głogowski, Robert; Chambers, Edgar

2018-05-23

Sensory analysis of pet foods has been emerging as an important field of study for the pet food industry over the last few decades. Few studies have been conducted on understanding the pet owners’ perception of pet foods. The objective of this study is to gain a deeper understanding on the perception of the visual characteristics of dry dog foods by dog owners in different consumer segments. A total of 120 consumers evaluated the appearance of 30 dry dog food samples with varying visual characteristics. The consumers rated the acceptance of the samples and associated each one with a list of positive and negative beliefs. Cluster Analysis, ANOVA and Correspondence Analysis were used to analyze the consumer responses. The acceptability of the appearance of dry dog foods was affected by the number of different kibbles present, color(s), shape(s), and size(s) of the kibbles in the product. Three consumer clusters were identified. Consumers rated highest single-kibble samples of medium sizes, traditional shapes, and brown colors. Participants disliked extra-small or extra-large kibble sizes, shapes with high-dimensional contrast, and kibbles of light brown color. These findings can help dry dog food manufacturers to meet consumers’ needs with increasing benefits to the pet food and commodity industries.

Relationships among vocabulary size, nonverbal cognition, and spoken word recognition in adults with cochlear implants

NASA Astrophysics Data System (ADS)

Collison, Elizabeth A.; Munson, Benjamin; Carney, Arlene E.

2002-05-01

Recent research has attempted to identify the factors that predict speech perception performance among users of cochlear implants (CIs). Studies have found that approximately 20%-60% of the variance in speech perception scores can be accounted for by factors including duration of deafness, etiology, type of device, and length of implant use, leaving approximately 50% of the variance unaccounted for. The current study examines the extent to which vocabulary size and nonverbal cognitive ability predict CI listeners' spoken word recognition. Fifteen postlingually deafened adults with nucleus or clarion CIs were given standardized assessments of nonverbal cognitive ability and expressive vocabulary size: the Expressive Vocabulary Test, the Test of Nonverbal Intelligence-III, and the Woodcock-Johnson-III Test of Cognitive Ability, Verbal Comprehension subtest. Two spoken word recognition tasks were administered. In the first, listeners identified isophonemic CVC words. In the second, listeners identified gated words varying in lexical frequency and neighborhood density. Analyses will examine the influence of lexical frequency and neighborhood density on the uniqueness point in the gating task, as well as relationships among nonverbal cognitive ability, vocabulary size, and the two spoken word recognition measures. [Work supported by NIH Grant P01 DC00110 and by the Lions 3M Hearing Foundation.

Size Constancy in Bat Biosonar? Perceptual Interaction of Object Aperture and Distance

PubMed Central

Heinrich, Melina; Wiegrebe, Lutz

2013-01-01

Perception and encoding of object size is an important feature of sensory systems. In the visual system object size is encoded by the visual angle (visual aperture) on the retina, but the aperture depends on the distance of the object. As object distance is not unambiguously encoded in the visual system, higher computational mechanisms are needed. This phenomenon is termed “size constancy”. It is assumed to reflect an automatic re-scaling of visual aperture with perceived object distance. Recently, it was found that in echolocating bats, the ‘sonar aperture’, i.e., the range of angles from which sound is reflected from an object back to the bat, is unambiguously perceived and neurally encoded. Moreover, it is well known that object distance is accurately perceived and explicitly encoded in bat sonar. Here, we addressed size constancy in bat biosonar, recruiting virtual-object techniques. Bats of the species Phyllostomus discolor learned to discriminate two simple virtual objects that only differed in sonar aperture. Upon successful discrimination, test trials were randomly interspersed using virtual objects that differed in both aperture and distance. It was tested whether the bats spontaneously assigned absolute width information to these objects by combining distance and aperture. The results showed that while the isolated perceptual cues encoding object width, aperture, and distance were all perceptually well resolved by the bats, the animals did not assign absolute width information to the test objects. This lack of sonar size constancy may result from the bats relying on different modalities to extract size information at different distances. Alternatively, it is conceivable that familiarity with a behaviorally relevant, conspicuous object is required for sonar size constancy, as it has been argued for visual size constancy. Based on the current data, it appears that size constancy is not necessarily an essential feature of sonar perception in bats. PMID:23630598

Size constancy in bat biosonar? Perceptual interaction of object aperture and distance.

PubMed

Heinrich, Melina; Wiegrebe, Lutz

2013-01-01

Perception and encoding of object size is an important feature of sensory systems. In the visual system object size is encoded by the visual angle (visual aperture) on the retina, but the aperture depends on the distance of the object. As object distance is not unambiguously encoded in the visual system, higher computational mechanisms are needed. This phenomenon is termed "size constancy". It is assumed to reflect an automatic re-scaling of visual aperture with perceived object distance. Recently, it was found that in echolocating bats, the 'sonar aperture', i.e., the range of angles from which sound is reflected from an object back to the bat, is unambiguously perceived and neurally encoded. Moreover, it is well known that object distance is accurately perceived and explicitly encoded in bat sonar. Here, we addressed size constancy in bat biosonar, recruiting virtual-object techniques. Bats of the species Phyllostomus discolor learned to discriminate two simple virtual objects that only differed in sonar aperture. Upon successful discrimination, test trials were randomly interspersed using virtual objects that differed in both aperture and distance. It was tested whether the bats spontaneously assigned absolute width information to these objects by combining distance and aperture. The results showed that while the isolated perceptual cues encoding object width, aperture, and distance were all perceptually well resolved by the bats, the animals did not assign absolute width information to the test objects. This lack of sonar size constancy may result from the bats relying on different modalities to extract size information at different distances. Alternatively, it is conceivable that familiarity with a behaviorally relevant, conspicuous object is required for sonar size constancy, as it has been argued for visual size constancy. Based on the current data, it appears that size constancy is not necessarily an essential feature of sonar perception in bats.

Size misperception among overweight and obese families.

PubMed

Paul, Tracy K; Sciacca, Robert R; Bier, Michael; Rodriguez, Juviza; Song, Sharon; Giardina, Elsa-Grace V

2015-01-01

Perception of body size is a key factor driving health behavior. Mothers directly influence children's nutritional and exercise behaviors. Mothers of ethnic minority groups and lower socioeconomic status are less likely to correctly identify young children as overweight or obese. Little evaluation has been done of the inverse--the child's perception of the mother's weight. To determine awareness of weight status among mother-child dyads (n = 506). Cross-sectional study conducted in an outpatient pediatric dental clinic of Columbia University Medical Center, New York, NY. Primarily Hispanic (82.2 %) mothers (n = 253), 38.8 ± 7.5 years of age, and children (n = 253), 10.5 ± 1.4 years of age, responding to a questionnaire adapted from the validated Behavioral Risk Factor Surveillance System. Anthropometric measures-including height, weight, and waist circumference-and awareness of self-size and size of other generation were obtained. 71.4 % of obese adults and 35.1 % of overweight adults underestimated size, vs. 8.6 % of normal-weight (NW) adults (both p < 0.001). Among overweight and obese children, 86.3 % and 62.3 % underestimated their size, vs. 14.9 % NW children (both p < 0.001). Among mothers with overweight children, 80.0 % underestimated their child's weight, vs. 7.1 % of mothers with NW children (p < 0.001); 23.1 % of mothers with obese children also underestimated their child's weight (p < 0.01). Among children with obese mothers, only 13.0 % correctly classified the adult's size, vs. 76.5 % with NW mothers (p < 0.001). Among obese mothers, 20.8 % classified overweight body size as ideal, vs. 1.2 % among NW mothers (p < 0.001). Overweight/obese adults and children frequently underestimate their size. Adults misjudge overweight/obese children as being of normal weight, and children of obese mothers often underestimate the adult's size. Failure to recognize overweight/obesity status among adults and children can lead to prolonged exposure to obesity-related comorbidities.

Mother-Reported and Children's Perceived Social and Academic Competence in Clinic-Referred Youth: Unique Relations to Depression and/or Social Anxiety and the Role of Self-perceptions.

PubMed

Epkins, Catherine C; Seegan, Paige L

2015-10-01

Depression and social anxiety symptoms and disorders are highly comorbid, and are associated with low social acceptance and academic competence. Theoretical models of both depression and social anxiety highlight the saliency of negative self-perceptions. We examined whether children's self-perceptions of social acceptance and mother-reported youth social acceptance are independently and uniquely related to children's depression and social anxiety, both before and after controlling for comorbid symptoms. Similar questions were examined regarding academic competence. The sample was 110 clinic-referred youth aged 8-16 years (65 boys, 45 girls; M age = 11.15, SD = 2.57). In the social acceptance area, both youth self-perceptions and mother-perceptions had independent and unique relations to depression and social anxiety, before and after controlling for comorbid symptoms. In the academic domain, both youth self-perceptions and mother-perceptions had independent and unique relations to depression, before and after controlling for social anxiety; yet only youth self-perceptions were related to social anxiety, before, but not after controlling for depression. For depression, larger effect sizes were observed for children's perceived, versus mother-reported, social acceptance and academic competence. Bootstrapping and Sobel tests found youth self-perceptions of social acceptance mediated the relation between mothers' perceptions and each of youth depression and social anxiety; and perceived academic competence mediated the relation between mothers' perceptions and youth depression, both before and after controlling for social anxiety. We found similarities and differences in findings for depression and social anxiety. Theoretical and treatment implications are highlighted, and future research directions are discussed.

HIV Risk Perception, HIV Knowledge, and Sexual Risk Behaviors among Transgender Women in South Florida.

PubMed

De Santis, Joseph P; Hauglum, Shayne D; Deleon, Diego A; Provencio-Vasquez, Elias; Rodriguez, Allan E

2017-05-01

Transgender women experience a variety of factors that may contribute to HIV risk. The purpose of this study was to explore links among HIV risk perception, knowledge, and sexual risk behaviors of transgender women. A descriptive, correlational study design was used. Fifty transgender women from the South Florida area were enrolled in the study. Transgender women completed a demographic questionnaire and standardized instruments measuring HIV risk perception, knowledge, and sexual risk behaviors. Transgender women reported low levels of HIV risk perception, and had knowledge deficits regarding HIV risk/transmission. Some participants engaged in high-risk sexual behaviors. Predictors of sexual risk behaviors among transgender women were identified. More research is needed with a larger sample size to continue studying factors that contribute to sexual risk behaviors in the understudied population of transgender women. Evidence-based guidelines are available to assist public health nurses in providing care for transgender women. Nurses must assess HIV perception risk and HIV knowledge and provide relevant education to transgender women on ways to minimize sexual risk. © 2016 Wiley Periodicals, Inc.

Developmental study of visual perception of handwriting movement: influence of motor competencies?

PubMed

Bidet-Ildei, Christel; Orliaguet, Jean-Pierre

2008-07-25

This paper investigates the influence of motor competencies for the visual perception of human movements in 6-10 years old children. To this end, we compared the kinematics of actual performed and perceptual preferred handwriting movements. The two children's tasks were (1) to write the letter e on a digitizer (handwriting task) and (2) to adjust the velocity of an e displayed on a screen so that it would correspond to "their preferred velocity" (perceptive task). In both tasks, the size of the letter (from 3.4 to 54.02 cm) was different on each trial. Results showed that irrespective of age and task, total movement time conforms to the isochrony principle, i.e., the tendency to maintain constant the duration of movement across changes of amplitude. However, concerning movement speed, there is no developmental correspondence between results obtained in the motor and the perceptive tasks. In handwriting task, movement time decreased with age but no effect of age was observed in the perceptive task. Therefore, perceptual preference of handwriting movement in children could not be strictly interpreted in terms of motor-perceptual coupling.

Accuracy of body image perception and preferred weight loss strategies in schizophrenia: a controlled pilot study.

PubMed

Loh, C; Meyer, J M; Leckband, S G

2008-02-01

Obesity in severely mentally ill (SMI) populations is an increasing problem, but there is no controlled data regarding the relationship between SMI and weight perception. Fifty patients with schizophrenia and 50 demographically matched control participants were recruited. Weight, height, and body image accuracy were assessed for all participants, and assessments of mood, psychotic symptom severity and anxiety, and preferred modes of weight loss were assessed for the schizophrenia sample. Patients with schizophrenia were significantly more likely to be obese than controls (46% vs. 18%, P < 0.005), and most patients expressed an interest in losing weight. Obese participants with schizophrenia underestimated their body size (11.0%) more than controls (4.9%) (P < 0.05). Patients with schizophrenia are more likely to underestimate their body size, independent of the effects of obesity. However, they also express concern about weight issues and willingness to participate in psychoeducational groups targeted at weight loss.

Validity of a figure rating scale assessing body size perception in school-age children.

PubMed

Lombardo, Caterina; Battagliese, Gemma; Pezzuti, Lina; Lucidi, Fabio

2014-01-01

This study aimed to provide data concerning the validity of a short sequence of face valid pictorial stimuli assessing the perception of body size in school-age children. A sequence of gender and age-appropriate silhouettes was administered to 314 boys and girls aged 6-14 years. The self-evaluations provided by the children correlated significantly with their actual BMI corrected for age. Furthermore, the children's self-evaluations always significantly correlated with the evaluations provided by the three external observers; i.e., both parents and the interviewers. The results indicate that this sequence of pictorial stimuli, depicting realistic human forms appropriate for children, is a valid measure of children's body image. Relevant differences across age groups were also found, indicating that before the age of eight, the correlations between the children's self-evaluations and their BMI or the judgments of the three observers are lower than in the other age groups.

Perceived value in food selection when dining out: comparison of African Americans and Euro-Americans.

PubMed

Vinci, Debra M; Philipp, Steven F

2007-06-01

This descriptive study compares African Americans' and Euro-Americans' perceived value of food selection pertaining to cost, portion size, and meal satisfaction when eating away from home. A stratified sample was drawn from a southern U.S. metropolitan area (N= 1,011; 486 African American, 525 Euro-American). Analysis showed no difference between African-American and Euro-American adults by sex or how often they dined out. These two groups significantly differed across years of education, age, and answering 14 of 18 rated statements on value perceptions. African-Americans' value perceptions were influenced more by lower cost foods and larger portion sizes than those of Euro-Americans. For meal satisfaction, African Americans were more likely to agree with statements that indicate preferring foods high in energy and low in essential micronutrient density. This study supports the need for more investigation.

Optimal Distinctiveness Signals Membership Trust.

PubMed

Leonardelli, Geoffrey J; Loyd, Denise Lewin

2016-07-01

According to optimal distinctiveness theory, sufficiently small minority groups are associated with greater membership trust, even among members otherwise unknown, because the groups are seen as optimally distinctive. This article elaborates on the prediction's motivational and cognitive processes and tests whether sufficiently small minorities (defined by relative size; for example, 20%) are associated with greater membership trust relative to mere minorities (45%), and whether such trust is a function of optimal distinctiveness. Two experiments, examining observers' perceptions of minority and majority groups and using minimal groups and (in Experiment 2) a trust game, revealed greater membership trust in minorities than majorities. In Experiment 2, participants also preferred joining minorities over more powerful majorities. Both effects occurred only when minorities were 20% rather than 45%. In both studies, perceptions of optimal distinctiveness mediated effects. Discussion focuses on the value of relative size and optimal distinctiveness, and when membership trust manifests. © 2016 by the Society for Personality and Social Psychology, Inc.

Low is large: spatial location and pitch interact in voice-based body size estimation.

PubMed

Pisanski, Katarzyna; Isenstein, Sari G E; Montano, Kelyn J; O'Connor, Jillian J M; Feinberg, David R

2017-05-01

The binding of incongruent cues poses a challenge for multimodal perception. Indeed, although taller objects emit sounds from higher elevations, low-pitched sounds are perceptually mapped both to large size and to low elevation. In the present study, we examined how these incongruent vertical spatial cues (up is more) and pitch cues (low is large) to size interact, and whether similar biases influence size perception along the horizontal axis. In Experiment 1, we measured listeners' voice-based judgments of human body size using pitch-manipulated voices projected from a high versus a low, and a right versus a left, spatial location. Listeners associated low spatial locations with largeness for lowered-pitch but not for raised-pitch voices, demonstrating that pitch overrode vertical-elevation cues. Listeners associated rightward spatial locations with largeness, regardless of voice pitch. In Experiment 2, listeners performed the task while sitting or standing, allowing us to examine self-referential cues to elevation in size estimation. Listeners associated vertically low and rightward spatial cues with largeness more for lowered- than for raised-pitch voices. These correspondences were robust to sex (of both the voice and the listener) and head elevation (standing or sitting); however, horizontal correspondences were amplified when participants stood. Moreover, when participants were standing, their judgments of how much larger men's voices sounded than women's increased when the voices were projected from the low speaker. Our results provide novel evidence for a multidimensional spatial mapping of pitch that is generalizable to human voices and that affects performance in an indirect, ecologically relevant spatial task (body size estimation). These findings suggest that crossmodal pitch correspondences evoke both low-level and higher-level cognitive processes.

Correlations between community size and student perceptions of value.

PubMed

Anderson, Susan M; Simanton, Edward

2017-01-01

The purpose of this study was to determine if medical students' feeling of being valued was correlated to community size. The study, conducted in several communities in South Dakota, examined students' feeling of value relating to attending physicians, healthcare teams and patients. Student value items were added to student satisfaction surveys sent out to students at the end of their primary clinical year and data collected from two graduating classes of students (n=114). Student responses were grouped by clinical campus and mean responses by community size were calculated. Additionally, student encounter logs were reviewed for study participants to gauge participation levels during clinical encounters. The degree to which students felt valued by their physician attending, the healthcare team and the patients decreased consistently as community size increased. Differences were statistically significant between students in the smallest and largest communities. Additionally, students in the community of 15 000 felt significantly more valued than students in the community of 170 000. Furthermore, there also appears to be a relationship between the percentage of participation in patient care by students and community size. Students in the smaller, rural communities participated at a higher percentage rather than observing. There appears to be a relationship between community size and the extent to which students feel value. The degree to which students felt valued decreased consistently as community size increased. Differences were statistically significant between students in the smallest communities and the two largest communities. Students in the smaller, rural communities participated at a higher percentage. Additional studies are needed to address whether students participate more as a result of feeling valued, or whether participation leads to an enhanced perception of value by students.

Illusory Distance Modulates Perceived Size of Afterimage despite the Disappearance of Depth Cues

PubMed Central

Liu, Shengxi; Lei, Quan

2016-01-01

It is known that the perceived size of an afterimage is modulated by the perceived distance between the observer and the depth plane on which the afterimage is projected (Emmert’s law). Illusions like Ponzo demonstrate that illusory distance induced by depth cues can also affect the perceived size of an object. In this study, we report that the illusory distance not only modulates the perceived size of object’s afterimage during the presence of the depth cues, but the modulation persists after the disappearance of the depth cues. We used an adapted version of the classic Ponzo illusion. Illusory depth perception was induced by linear perspective cues with two tilted lines converging at the upper boundary of the display. Two horizontal bars were placed between the two lines, resulting in a percept of the upper bar to be farther away than the lower bar. Observers were instructed to make judgment about the relative size of the afterimage of the lower and the upper bars after adaptation. When the perspective cues and the bars were static, the illusory effect of the Ponzo afterimage is consistent with that of the traditional size-distance illusion. When the perspective cues were flickering and the bars were static, only the afterimage of the latter was perceived, yet still a considerable amount of the illusory effect was perceived. The results could not be explained by memory of a prejudgment of the bar length during the adaptation phase. The findings suggest that cooccurrences of depth cues and object may link a depth marker for the object, so that the perceived size of the object or its afterimage is modulated by feedback of depth information from higher-level visual cortex even when there is no depth cues directly available on the retinal level. PMID:27391335

The moon illusion and size-distance scaling--evidence for shared neural patterns.

PubMed

Weidner, Ralph; Plewan, Thorsten; Chen, Qi; Buchner, Axel; Weiss, Peter H; Fink, Gereon R

2014-08-01

A moon near to the horizon is perceived larger than a moon at the zenith, although--obviously--the moon does not change its size. In this study, the neural mechanisms underlying the "moon illusion" were investigated using a virtual 3-D environment and fMRI. Illusory perception of an increased moon size was associated with increased neural activity in ventral visual pathway areas including the lingual and fusiform gyri. The functional role of these areas was further explored in a second experiment. Left V3v was found to be involved in integrating retinal size and distance information, thus indicating that the brain regions that dynamically integrate retinal size and distance play a key role in generating the moon illusion.

Transfer of adaptation reveals shared mechanism in grasping and manual estimation.

PubMed

Cesanek, Evan; Domini, Fulvio

2018-06-19

An influential idea in cognitive neuroscience is that perception and action are highly separable brain functions, implemented in distinct neural systems. In particular, this theory predicts that the functional distinction between grasping, a skilled action, and manual estimation, a type of perceptual report, should be mirrored by a split between their respective control systems. This idea has received support from a variety of dissociations, yet many of these findings have been criticized for failing to pinpoint the source of the dissociation. In this study, we devised a novel approach to this question, first targeting specific grasp control mechanisms through visuomotor adaptation, then testing whether adapted mechanisms were also involved in manual estimation - a response widely characterized as perceptual in function. Participants grasped objects in virtual reality that could appear larger or smaller than the actual physical sizes felt at the end of each grasp. After brief exposure to a size perturbation, manual estimates were biased in the same direction as the maximum grip apertures of grasping movements, indicating that the adapted mechanism is active in both tasks, regardless of the perception-action distinction. Additional experiments showed that the transfer effect generalizes broadly over space (Exp. 1B) and does not appear to arise from a change in visual perception (Exp. 2). We discuss two adaptable mechanisms that could have mediated the observed effect: (a) an afferent proprioceptive mechanism for sensing grip shape; and (b) an efferent visuomotor transformation of size information into a grip-shaping motor command. Copyright © 2018. Published by Elsevier Ltd.

A RAND Analysis Tool for Intelligence, Surveillance, and Reconnaissance: The Collections Operations Model

DTIC Science & Technology

2008-01-01

appropriate; scan cycle, emission interval, or emission probability; frequency bands; relative angular size of 2 Carl Rhodes, Jeff Hagen, and Mark...choices based on its own perceptions. An agent has autonomy. 2 In this report, “behaviors” are individual scripts , programs, instructions, or decision...relative angular size of main and side lobes (for directional signals); and the effective radiated power of each radiative lobe. With these parameters and

Interactions between whey proteins and salivary proteins as related to astringency of whey protein beverages at low pH.

PubMed

Ye, A; Streicher, C; Singh, H

2011-12-01

Whey protein beverages have been shown to be astringent at low pH. In the present study, the interactions between model whey proteins (β-lactoglobulin and lactoferrin) and human saliva in the pH range from 7 to 2 were investigated using particle size, turbidity, and ζ-potential measurements and sodium dodecyl sulfate-PAGE. The correlation between the sensory results of astringency and the physicochemical data was discussed. Strong interactions between β-lactoglobulin and salivary proteins led to an increase in the particle size and turbidity of mixtures of both unheated and heated β-lactoglobulin and human saliva at pH ∼3.4. However, the large particle size and high turbidity that occurred at pH 2.0 were the result of aggregation of human salivary proteins. The intense astringency in whey protein beverages may result from these increases in particle size and turbidity at these pH values and from the aggregation and precipitation of human salivary proteins alone at pH <3.0. The involvement of salivary proteins in the interaction is a key factor in the perception of astringency in whey protein beverages. At any pH, the increases in particle size and turbidity were much smaller in mixtures of lactoferrin and saliva, which suggests that aggregation and precipitation may not be the only mechanism linked to the perception of astringency in whey protein. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Mismatched summation mechanisms in older adults for the perception of small moving stimuli.

PubMed

McDougall, Thomas J; Nguyen, Bao N; McKendrick, Allison M; Badcock, David R

2018-01-01

Previous studies have found evidence for reduced cortical inhibition in aging visual cortex. Reduced inhibition could plausibly increase the spatial area of excitation in receptive fields of older observers, as weaker inhibitory processes would allow the excitatory receptive field to dominate and be psychophysically measureable over larger areas. Here, we investigated aging effects on spatial summation of motion direction using the Battenberg summation method, which aims to control the influence of locally generated internal noise changes by holding overall display size constant. This method produces more accurate estimates of summation area than conventional methods that simply increase overall stimulus dimensions. Battenberg stimuli have a checkerboard arrangement, where check size (luminance-modulated drifting gratings alternating with mean luminance areas), but not display size, is varied and compared with performance for a full field stimulus to provide a measure of summation. Motion direction discrimination thresholds, where contrast was the dependent variable, were measured in 14 younger (24-34 years) and 14 older (62-76 years) adults. Older observers were less sensitive for all check sizes, but the relative sensitivity across sizes, also differed between groups. In the older adults, the full field stimulus offered smaller performance improvements compared to that for younger adults, specifically for the small checked Battenberg stimuli. This suggests aging impacts on short-range summation mechanisms, potentially underpinned by larger summation areas for the perception of small moving stimuli. Copyright © 2017 Elsevier Ltd. All rights reserved.

Social class and family size as determinants of attributed machismo, femininity, and family planning: a field study in two South American communities.

PubMed

Nicassio, P M

1977-12-01

A study was conducted to determine the way in which stereotypes of machismo and femininity are associated with family size and perceptions of family planning. A total of 144 adults, male and female, from a lower class and an upper middle class urban area in Colombia were asked to respond to photographs of Colombian families varying in size and state of completeness. The study illustrated the critical role of sex-role identity and sex-role organization as variables having an effect on fertility. The lower-class respondents described parents in the photographs as significantly more macho or feminine because of their children than the upper-middle-class subjects did. Future research should attempt to measure when this drive to sex-role identity is strongest, i.e., when men and women are most driven to reproduce in order to "prove" themselves. Both lower- and upper-middle-class male groups considered male dominance in marriage to be directly linked with family size. Perceptions of the use of family planning decreased linearly with family size for both social groups, although the lower-class females attributed more family planning to spouses of large families than upper-middle-class females. It is suggested that further research deal with the ways in which constructs of machismo and male dominance vary between the sexes and among socioeconomic groups and the ways in which they impact on fertility.

Law enforcement officers’ risk perceptions toward on-duty motor-vehicle events

PubMed Central

Tiesman, Hope M.; Heick, Rebecca J.; Konda, Srinivas; Hendricks, Scott

2015-01-01

Purpose Motor-vehicle-related events (MVEs) are the leading cause of on-duty death for law enforcement officers, yet little is known about how officers view this significant job hazard. The purpose of this paper is to explore officers’ motor-vehicle risk perception and examine how prior on-duty MVEs and the death or injury of a fellow officer influences this perception. Design/methodology/approach A state-wide random sample of 136 law enforcement agencies was drawn using publically accessible databases, stratified on type and size of agency. In total, 60 agencies agreed to participate and a cross-sectional questionnaire was distributed to 1,466 officers. Using six-point Likert scales, composite scores for motor-vehicle and intentional violence risk perception were derived. A linear regression multivariable model was used to examine factors affecting motor-vehicle risk perception. Findings Motor-vehicle risk perception scores were significantly higher than intentional violence scores. A prior on-duty motor-vehicle crash, prior roadside incident, or knowledge of fellow officer’s injury or death from a MVE significantly increased motor-vehicle risk perception scores. After controlling for potential confounders though, only prior on-duty crashes and roadside incidents impacted motor-vehicle risk perception. Research limitations/implications The study comprised primarily small, rural agencies and generalizability may be limited. Also, although the data were collected anonymously, reporting and response biases may affect these findings. Originality/value This study involved a large and diverse cohort of officers and explored motor-vehicle risk perception. A better understanding of officers’ risk perceptions will assist in the development and implementation of occupational injury prevention programs, training, and policy. PMID:26380563

Relationship between auditory perception and vocal production in cochlear implantees: a systematic review.

PubMed

Cysneiros, Helena Renata Silva; Leal, Mariana de Carvalho; Lucena, Jonia Alves; Muniz, Lilian Ferreira

To conduct a systematic review of the scientific literature studying the relationship between vocal production and auditory perception in cochlear implant users. This is an integrative systematic review. The plattforms/databases Bireme, SciELO, Cochrane, Scopus and Web of Science were consulted and the descriptors used were voice, cochlear implant and auditory perception. Original papers published in English, French, Spanish or Portuguese involving the study of vocal production and auditory perception in cochlear implant users were selected and there was no restriction about year of publication of the articles. The studies selected were analyzed according to the author, location, year and publication of the article, as well as for their sample size, type of vocal production and auditory perception assessment and for its major findings and recommendation grade/level of scientific evidence. The results suggest the existence of positive relationship between vocal production and auditory perception in cochlear implant users, and indicate that the deployment time has a positive influence in this relationship. None of the selected studies were rated at level 1 of scientific evidence or grade A of recommendation, which is related to the methodological approach that can go with this subject matter. There is great lack of publications relating auditory perception and speech production in cochlear implant users. This gap is even greater when it comes to the adult population.

A neural interface provides long-term stable natural touch perception.

PubMed

Tan, Daniel W; Schiefer, Matthew A; Keith, Michael W; Anderson, James Robert; Tyler, Joyce; Tyler, Dustin J

2014-10-08

Touch perception on the fingers and hand is essential for fine motor control, contributes to our sense of self, allows for effective communication, and aids in our fundamental perception of the world. Despite increasingly sophisticated mechatronics, prosthetic devices still do not directly convey sensation back to their wearers. We show that implanted peripheral nerve interfaces in two human subjects with upper limb amputation provided stable, natural touch sensation in their hands for more than 1 year. Electrical stimulation using implanted peripheral nerve cuff electrodes that did not penetrate the nerve produced touch perceptions at many locations on the phantom hand with repeatable, stable responses in the two subjects for 16 and 24 months. Patterned stimulation intensity produced a sensation that the subjects described as natural and without "tingling," or paresthesia. Different patterns produced different types of sensory perception at the same location on the phantom hand. The two subjects reported tactile perceptions they described as natural tapping, constant pressure, light moving touch, and vibration. Changing average stimulation intensity controlled the size of the percept area; changing stimulation frequency controlled sensation strength. Artificial touch sensation improved the subjects' ability to control grasping strength of the prosthesis and enabled them to better manipulate delicate objects. Thus, electrical stimulation through peripheral nerve electrodes produced long-term sensory restoration after limb loss. Copyright © 2014, American Association for the Advancement of Science.

A neural interface provides long-term stable natural touch perception

PubMed Central

Tan, Daniel W.; Schiefer, Matthew A.; Keith, Michael W.; Anderson, James Robert; Tyler, Joyce; Tyler, Dustin J.

2017-01-01

Touch perception on the fingers and hand is essential for fine motor control, contributes to our sense of self, allows for effective communication, and aids in our fundamental perception of the world. Despite increasingly sophisticated mechatronics, prosthetic devices still do not directly convey sensation back to their wearers. We show that implanted peripheral nerve interfaces in two human subjects with upper limb amputation provided stable, natural touch sensation in their hands for more than 1 year. Electrical stimulation using implanted peripheral nerve cuff electrodes that did not penetrate the nerve produced touch perceptions at many locations on the phantom hand with repeatable, stable responses in the two subjects for 16 and 24 months. Patterned stimulation intensity produced a sensation that the subjects described as natural and without “tingling,” or paresthesia. Different patterns produced different types of sensory perception at the same location on the phantom hand. The two subjects reported tactile perceptions they described as natural tapping, constant pressure, light moving touch, and vibration. Changing average stimulation intensity controlled the size of the percept area; changing stimulation frequency controlled sensation strength. Artificial touch sensation improved the subjects’ ability to control grasping strength of the prosthesis and enabled them to better manipulate delicate objects. Thus, electrical stimulation through peripheral nerve electrodes produced long-term sensory restoration after limb loss. PMID:25298320

Measuring the size of an earthquake

USGS Publications Warehouse

Spence, W.

1977-01-01

Earthquakes occur in a broad range of sizes. A rock burst in an Idaho silver mine may involve the fracture of 1 meter of rock; the 1965 Rat island earthquake in the Aleutian arc involved a 650-kilometer lenght of Earth's crust. Earthquakes can be even smaller and even larger. if an earthquake is felt or causes perceptible surface damage, then its intesnity of shaking can be subjectively estimated. But many large earthquakes occur in oceanic area or at great focal depths. These are either simply not felt or their felt pattern does not really indicate their true size. 

The portion size effect on food intake is robust to contextual size information.

PubMed

Reily, Natalie M; Vartanian, Lenny R

2016-10-01

Larger portion sizes have consistently been shown to lead to greater food intake. However, studies of the portion size effect typically provided participants with a single portion of food at a time without any objective information about the size of the portion, and hence failed to consider the potential significance of contextual size information. In order to investigate whether contextual size information moderates the portion size effect, participants were served small or large portions of pasta for lunch in the presence or absence of contextual size information. Study 1 found that the portion size effect on food intake was robust to contextual size information. Study 2 replicated this finding in an online paradigm, showing that contextual size information also had no influence on prospective intake, even when participants chose the portion size they preferred. Both studies also showed that participants' perceptions of how much was appropriate to eat mediated the effect of portion size on intake. A practical implication of our findings is that modifying consumption norms may be an effective way to promote healthier consumer food decisions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Gradients of fear: How perception influences fear generalization.

PubMed

Struyf, Dieter; Zaman, Jonas; Hermans, Dirk; Vervliet, Bram

2017-06-01

The current experiment investigated whether overgeneralization of fear could be due to an inability to perceptually discriminate the initial fear-evoking stimulus from similar stimuli, as fear learning-induced perceptual impairments have been reported but their influence on generalization gradients remain to be elucidated. Three hundred and sixty-eight healthy volunteers participated in a differential fear conditioning paradigm with circles of different sizes as conditioned stimuli (CS), of which one was paired to an aversive IAPS picture. During generalization, each subject was presented with one of 10 different sized circles including the CSs, and were asked to categorize the stimulus as either a CS or as novel after fear responses were recorded. Linear mixed models were used to investigate differences in fear generalization gradients depending on the participant's perception of the test stimulus. We found that the incorrect perception of a novel stimulus as the initial fear-evoking stimulus strongly boosted fear responses. The current findings demonstrate that a significant number of novel stimuli used to assess generalization are incorrectly identified as the initial fear-evoking stimulus, providing a perceptual account for the observed overgeneralization in panic and anxiety disorders. Accordingly, enhancing perceptual processing may be a promising treatment for targeting excessive fear generalization. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Optimal faces for gender and expression: a new technique for measuring dynamic templates used in face perception.

PubMed

Poirier, Frédéric J A M; Faubert, Jocelyn

2012-06-22

Facial expressions are important for human communications. Face perception studies often measure the impact of major degradation (e.g., noise, inversion, short presentations, masking, alterations) on natural expression recognition performance. Here, we introduce a novel face perception technique using rich and undegraded stimuli. Participants modified faces to create optimal representations of given expressions. Using sliders, participants adjusted 53 face components (including 37 dynamic) including head, eye, eyebrows, mouth, and nose shape and position. Data was collected from six participants and 10 conditions (six emotions + pain + gender + neutral). Some expressions had unique features (e.g., frown for anger, upward-curved mouth for happiness), whereas others had shared features (e.g., open eyes and mouth for surprise and fear). Happiness was different from other emotions. Surprise was different from other emotions except fear. Weighted sum morphing provides acceptable stimuli for gender-neutral and dynamic stimuli. Many features were correlated, including (1) head size with internal feature sizes as related to gender, (2) internal feature scaling, and (3) eyebrow height and eye openness as related to surprise and fear. These findings demonstrate the method's validity for measuring the optimal facial expressions, which we argue is a more direct measure of their internal representations.

Occupants' Perceptions of Amenity and Efficiency for Verification of Spatial Design Adequacy.

PubMed

Lee, Sangwon; Wohn, Kwangyun

2016-01-14

The best spatial design condition to satisfy the occupancy needs of amenity and efficiency is determined through analyzing the spatial design adequacy (SDA). In this study, the relationship between the space design elements and space on future occupants' perception are analyzed. The thirty-three participants reported their self-evaluated SDA that describes the quality of eight alternative housing living rooms with different spatial factors. The occupants were guided through the perception processing elaboration in order for them to evaluate the actual perception in the real space. The findings demonstrated that the spatial size (e.g., width, depth, and height) is significantly correlated with the overall satisfaction of amenity. It is also found that the spatial shape (e.g., the width-to-depth ratio, the height-to-area ratio, and room shape) may significantly influence the overall satisfaction of efficiency. The findings also demonstrate that the causal relationship between the spatial factors and space is clearly present in the occupants' perception, reflecting the time-sequential characteristics of the actual experience divided into amenity and efficiency. This result indicates that the correlation between the spatial factors and space of SDA under the occupants' perception processing elaboration can be a useful guide to predict the occupancy satisfaction of amenity and efficiency in real spaces.

Occupants’ Perceptions of Amenity and Efficiency for Verification of Spatial Design Adequacy

PubMed Central

Lee, Sangwon; Wohn, Kwangyun

2016-01-01

The best spatial design condition to satisfy the occupancy needs of amenity and efficiency is determined through analyzing the spatial design adequacy (SDA). In this study, the relationship between the space design elements and space on future occupants’ perception are analyzed. The thirty-three participants reported their self-evaluated SDA that describes the quality of eight alternative housing living rooms with different spatial factors. The occupants were guided through the perception processing elaboration in order for them to evaluate the actual perception in the real space. The findings demonstrated that the spatial size (e.g., width, depth, and height) is significantly correlated with the overall satisfaction of amenity. It is also found that the spatial shape (e.g., the width-to-depth ratio, the height-to-area ratio, and room shape) may significantly influence the overall satisfaction of efficiency. The findings also demonstrate that the causal relationship between the spatial factors and space is clearly present in the occupants’ perception, reflecting the time-sequential characteristics of the actual experience divided into amenity and efficiency. This result indicates that the correlation between the spatial factors and space of SDA under the occupants’ perception processing elaboration can be a useful guide to predict the occupancy satisfaction of amenity and efficiency in real spaces. PMID:26784211

Perceptions of Depression and Access to Mental Health Care Among Latino Immigrants: Looking Beyond One Size Fits All.

PubMed

Martinez Tyson, Dinorah; Arriola, Nora B; Corvin, Jaime

2016-07-01

Compared with non-Latino Whites, Latino immigrants have a lower prevalence of depression. However, they are also less likely to seek professional mental health services. Our objective was to compare and contrast perceptions of depression and access to mental health care among four of the largest Latino immigrant subgroups in Florida (Puerto Rican, Cuban, Mexican, and Colombian). We conducted a total of 120 interviews (30 men and women from each subgroup). Thematic analysis of qualitative data revealed that participants across the four groups were aware of the signs and symptoms of depression and had similar perceptions of depression. However, notable differences by subgroup emerged with regard to perceptions of access to mental health care. We suggest that the variation stems from differences in life experiences and the immigration context. Understanding the variances and nuances of Latino immigrants' cultural construction of depression and immigration experience will enable practitioners to better serve this community. © The Author(s) 2015.

The effects of earthquake measurement concepts and magnitude anchoring on individuals' perceptions of earthquake risk

USGS Publications Warehouse

Celsi, R.; Wolfinbarger, M.; Wald, D.

2005-01-01

The purpose of this research is to explore earthquake risk perceptions in California. Specifically, we examine the risk beliefs, feelings, and experiences of lay, professional, and expert individuals to explore how risk is perceived and how risk perceptions are formed relative to earthquakes. Our results indicate that individuals tend to perceptually underestimate the degree that earthquake (EQ) events may affect them. This occurs in large part because individuals' personal felt experience of EQ events are generally overestimated relative to experienced magnitudes. An important finding is that individuals engage in a process of "cognitive anchoring" of their felt EQ experience towards the reported earthquake magnitude size. The anchoring effect is moderated by the degree that individuals comprehend EQ magnitude measurement and EQ attenuation. Overall, the results of this research provide us with a deeper understanding of EQ risk perceptions, especially as they relate to individuals' understanding of EQ measurement and attenuation concepts. ?? 2005, Earthquake Engineering Research Institute.

The reasonable woman standard: a meta-analytic review of gender differences in perceptions of sexual harassment.

PubMed

Blumenthal, J A

1998-02-01

Courts and legislatures have begun to develop the "reasonable woman standard" (RWS) as a criterion for deciding sexual harassment trials. This standard rests on assumptions of a "wide divergence" between the perceptions of men and women when viewing social-sexual behavior that may be considered harassing. Narrative reviews of the literature on such perceptions have suggested that these assumptions are only minimally supported. To test these assumptions quantitatively, a meta-analytic review was conducted that assessed the size, stability, and moderators of gender differences in perceptions of sexual harassment. The effect of the actor's status relative to the target also was evaluated meta-analytically, as one alternative to the importance of gender effects. Results supported the claims of narrative reviews for a relatively small gender effect, and draw attention to the status effect. In discussing legal implications of the present findings, earlier claims are echoed suggesting caution in establishing the reasonable woman standard, and one alternative to the RWS, the "reasonable victim standard," is discussed.

Losing face: impaired discrimination of featural and configural information in the mouth region of an inverted face.

PubMed

Tanaka, James W; Kaiser, Martha D; Hagen, Simen; Pierce, Lara J

2014-05-01

Given that all faces share the same set of features-two eyes, a nose, and a mouth-that are arranged in similar configuration, recognition of a specific face must depend on our ability to discern subtle differences in its featural and configural properties. An enduring question in the face-processing literature is whether featural or configural information plays a larger role in the recognition process. To address this question, the face dimensions task was designed, in which the featural and configural properties in the upper (eye) and lower (mouth) regions of a face were parametrically and independently manipulated. In a same-different task, two faces were sequentially presented and tested in their upright or in their inverted orientation. Inversion disrupted the perception of featural size (Exp. 1), featural shape (Exp. 2), and configural changes in the mouth region, but it had relatively little effect on the discrimination of featural size and shape and configural differences in the eye region. Inversion had little effect on the perception of information in the top and bottom halves of houses (Exp. 3), suggesting that the lower-half impairment was specific to faces. Spatial cueing to the mouth region eliminated the inversion effect (Exp. 4), suggesting that participants have a bias to attend to the eye region of an inverted face. The collective findings from these experiments suggest that inversion does not differentially impair featural or configural face perceptions, but rather impairs the perception of information in the mouth region of the face.

Correlates of self worth and body size dissatisfaction among obese Latino youth

PubMed Central

Mirza, Nazrat M; Mackey, Eleanor Race; Armstrong, Bridget; Jaramillo, Ana; Palmer, Matilde M

2011-01-01

The current study examined self-worth and body size dissatisfaction, and their association with maternal acculturation among obese Latino youth enrolled in a community-based obesity intervention program. Upon entry to the program, a sample of 113 participants reported global self-worth comparable to general population norms, but lower athletic competence and perception of physical appearance. Interestingly, body size dissatisfaction was more prevalent among younger respondents. Youth body size dissatisfaction was associated with less acculturated mothers and higher maternal dissatisfaction with their child's body size. By contrast, although global self-worth was significantly related to body dissatisfaction, it was not influenced by mothers’ acculturation or dissatisfaction with their own or their child’s body size. Obesity intervention programs targeted to Latino youth need to address self-worth concerns among the youth as well as addressing maternal dissatisfaction with their children’s body size. PMID:21354881

Coordinate Transformations in Object Recognition

ERIC Educational Resources Information Center

Graf, Markus

2006-01-01

A basic problem of visual perception is how human beings recognize objects after spatial transformations. Three central classes of findings have to be accounted for: (a) Recognition performance varies systematically with orientation, size, and position; (b) recognition latencies are sequentially additive, suggesting analogue transformation…

Visual perception of writing and pointing movements.

PubMed

Méary, David; Chary, Catherine; Palluel-Germain, Richard; Orliaguet, Jean-Pierre

2005-01-01

Studies of movement production have shown that the relationship between the amplitude of a movement and its duration varies according to the type of gesture. In the case of pointing movements the duration increases as a function of distance and width of the target (Fitts' law), whereas for writing movements the duration tends to remain constant across changes in trajectory length (isochrony principle). We compared the visual perception of these two categories of movement. The participants judged the speed of a light spot that portrayed the motion of the end-point of a hand-held pen (pointing or writing). For the two types of gesture we used 8 stimulus sizes (from 2.5 cm to 20 cm) and 32 durations (from 0.2 s to 1.75 s). Viewing each combination of size and duration, participants had to indicate whether the movement speed seemed "fast", "slow", or "correct". Results showed that the participants' perceptual preferences were in agreement with the rules of movement production. The stimulus size was more influential in the pointing condition than in the writing condition. We consider that this finding reflects the influence of common representational resources for perceptual judgment and movement production.

Emotive hemispheric differences measured in real-life portraits using pupil diameter and subjective aesthetic preferences.

PubMed

Blackburn, Kelsey; Schirillo, James

2012-06-01

The biased positioning of faces exposed to viewers of Western portraiture has suggested there may be fundamental differences in the lateralized expression and perception of emotion. The present study investigates whether there are differences in the perception of the left and right sides of the face in real-life photographs of individuals. The study paired conscious aesthetic ratings of pleasantness with measurements of pupil size, which are thought to be a reliable unconscious measure of interest first tested by Hess. Images of 10 men and 10 women were taken from the left and right sides of the face. These images were also mirror-reversed. As expected, we found a strong preference for left-sided portraits (regardless of original or mirror-reversed orientation), such that left hemifaces elicited higher ratings and greater pupil dilation. Interestingly, this effect was true of both sexes. A positive linear relationship was also found between pupil size and aesthetic ratings such that pupil size increased with pleasantness ratings. These findings provide support for the notions of lateralized emotion, right-hemispheric dominance, pupillary dilation to pleasant images, and constriction to unpleasant images.

Vulnerability of reactive skin to electric current perception--a pilot study implicating mast cells and the lymphatic microvasculature.

PubMed

Quatresooz, Pascale; Piérard-Franchimont, Claudine; Piérard, Gérald E

2009-09-01

Sensitive/reactive skin is regarded as a manifestation of sensory irritation. This susceptibility condition to various exogenous factors suggests the intervention of some neuropeptides and other neurobiological mediators. Mast cells are among the putative implicated cells. The present immunohistochemical and morphometric study was performed on two groups of 36 gender- and age-matched subjects complaining or not from reactive skin as determined by electric current perception. In the mid upper part of the dermis, the numerical density in mast cells and the size of the microvasculature were assessed distinguishing the blood and lymphatic vessels. Globally, the distributions of data were large in reactive skin. This condition was characterized by a prominent increase in both the numerical density in mast cells and the overall size of the lymphatics. By contrast, no difference was found in the size of cutaneous blood vessels. More precisely, it appeared that a subgroup of people with reactive skin exhibited these changes contrasting with some other individuals whose data remained close to the normal range. Mast cells and lymphatics are probably involved in the process of sensory irritation affecting a subgroup of the population.

Effect of Display Technology on Perceived Scale of Space.

PubMed

Geuss, Michael N; Stefanucci, Jeanine K; Creem-Regehr, Sarah H; Thompson, William B; Mohler, Betty J

2015-11-01

Our goal was to evaluate the degree to which display technologies influence the perception of size in an image. Research suggests that factors such as whether an image is displayed stereoscopically, whether a user's viewpoint is tracked, and the field of view of a given display can affect users' perception of scale in the displayed image. Participants directly estimated the size of a gap by matching the distance between their hands to the gap width and judged their ability to pass unimpeded through the gap in one of five common implementations of three display technologies (two head-mounted displays [HMD] and a back-projection screen). Both measures of gap width were similar for the two HMD conditions and the back projection with stereo and tracking. For the displays without tracking, stereo and monocular conditions differed from each other, with monocular viewing showing underestimation of size. Display technologies that are capable of stereoscopic display and tracking of the user's viewpoint are beneficial as perceived size does not differ from real-world estimates. Evaluations of different display technologies are necessary as display conditions vary and the availability of different display technologies continues to grow. The findings are important to those using display technologies for research, commercial, and training purposes when it is important for the displayed image to be perceived at an intended scale. © 2015, Human Factors and Ergonomics Society.

Is obesity contagious by way of body image? A study on Japanese female students in the United States.

PubMed

Bagrowicz, Rinako; Watanabe, Chiho; Umezaki, Masahiro

2013-10-01

Although it has been suggested that obesity is 'contagious' within the social network, direct cause of this spread of obesity remains unclear. This study hypothesized that Body Image (BI), the perception of one's own body size, may play a role in this obesity spread, since a high prevalence of obesity could shift people's perception of 'what is normal'. Young Japanese females (n = 53) were interviewed within 1 month after moving to New York City, where the prevalence of obesity is substantially higher than that of their home country, Japan. Each participant was examined for her BI in terms of current body size (CBS) and ideal body size (IBS). They were interviewed again 2 months after the first examination. Between the two interviews, the participants' CBS was decreased (having thinner self-image), while the IBS increased (having fatter ideal-image), leading to less dissatisfaction (smaller CBS-IBS) with their body size. These results suggest that one's BI could change in a period as short as 2 months, possibly because of being surrounded by more obese people. The IBS change was positively associated with BMI change (increased by 0.4 ± 0.6 kg/m²), warranting further study on the role of BI in the spread of obesity.

Relationship between self-discrepancy and worries about penis size in men with body dysmorphic disorder.

PubMed

Veale, David; Miles, Sarah; Read, Julie; Bramley, Sally; Troglia, Andrea; Carmona, Lina; Fiorito, Chiara; Wells, Hannah; Wylie, Kevan; Muir, Gordon

2016-06-01

We explored self-discrepancy in men with body dysmorphic disorder (BDD) concerned about penis size, men without BDD but anxious about penis size, and controls. Men with BDD (n=26) were compared to those with small penis anxiety (SPA; n=31) and controls (n=33), objectively (by measuring) and investigating self-discrepancy: actual size, ideal size, and size they felt they should be according to self and other. Most men under-estimated their penis size, with the BDD group showing the greatest discrepancy between perceived and ideal size. The SPA group showed a larger discrepancy than controls. This was replicated for the perceptions of others, suggesting the BDD group internalised the belief that they should have a larger penis size. There was a significant correlation between symptoms of BDD and this discrepancy. This self-actual and self-ideal/self-should discrepancy and the role of comparing could be targeted in therapy. Copyright © 2016. Published by Elsevier Ltd.

Neural responses to sounds presented on and off the beat of ecologically valid music

PubMed Central

Tierney, Adam; Kraus, Nina

2013-01-01

The tracking of rhythmic structure is a vital component of speech and music perception. It is known that sequences of identical sounds can give rise to the percept of alternating strong and weak sounds, and that this percept is linked to enhanced cortical and oscillatory responses. The neural correlates of the perception of rhythm elicited by ecologically valid, complex stimuli, however, remain unexplored. Here we report the effects of a stimulus' alignment with the beat on the brain's processing of sound. Human subjects listened to short popular music pieces while simultaneously hearing a target sound. Cortical and brainstem electrophysiological onset responses to the sound were enhanced when it was presented on the beat of the music, as opposed to shifted away from it. Moreover, the size of the effect of alignment with the beat on the cortical response correlated strongly with the ability to tap to a beat, suggesting that the ability to synchronize to the beat of simple isochronous stimuli and the ability to track the beat of complex, ecologically valid stimuli may rely on overlapping neural resources. These results suggest that the perception of musical rhythm may have robust effects on processing throughout the auditory system. PMID:23717268

Safety culture in the operating room of a public hospital in the perception of healthcare professionals1

PubMed Central

Carvalho, Paloma Aparecida; Göttems, Leila Bernarda Donato; Pires, Maria Raquel Gomes Maia; de Oliveira, Maria Liz Cunha

2015-01-01

Objective: to evaluate the perception of healthcare professionals about the safety culture in the operating room of a public hospital, large-sized, according to the domains of the Safety Attitudes Questionnaire (SAQ). Method: descriptive, cross-sectional and quantitative research, with the application of the SAQ to 226 professionals. Descriptive data analysis, instrument consistency and exploratory factor analysis. Results: participants were distributed homogeneously between females (49.6%) and males (50.4%); mean age of 39.6 (SD±9.9) years and length of professional experience of 9.9 (SD±9.2) years. And Cronbach's ( of 0.84. It was identified six domains proposed in the questionnaire: stress perception (74.5) and job satisfaction (70.7) showed satisfactory results; teamwork environment (59.1) and climate of security (48.9) presented scores below the minimum recommended (75); unit's management perceptions (44.5), hospital management perceptions (34.9) and working conditions (41.9) presented the lowest averages. Conclusions: the results showed that, from the perspective of the professionals, there is weakness in the values, attitudes, skills and behaviors that determine the safety culture in a healthcare organization. PMID:26625994

Problems in depth perception : equidistance judgments in the vicinity of a binocular illusion.

DOT National Transportation Integrated Search

1966-07-01

Judgments of the size and distance of objects are sometimes made in aircraft under background-viewing conditions that may themselves create false sensory impressions (illusions). In this study, the effects of a background illusion on judgments of the...

The Effect of Comparatively-Framed versus Similarity-Framed E-Cigarette and Snus Print Ads on Young Adults’ Ad and Product Perceptions

PubMed Central

Banerjee, Smita C.; Greene, Kathryn; Li, Yuelin; Ostroff, Jamie S.

2016-01-01

Objectives This study examined the effects of comparative-framing [C-F; ads highlighting differences between the advertised product and conventional cigarettes and/or smokeless tobacco products] versus similarity-framing (S-F; ads highlighting congruence with conventional cigarettes and/or smokeless tobacco products) in e-cigarette and snus ads on young adult smokers’ and non-smokers’ ad- and product-related perceptions. Methods One thousand fifty one (1,051) young adults (18–24 years; 76% women; 50% smokers) from existing consumer panels were recruited in a within-subjects quasi-experiment. Each participant viewed 4 online advertisements, varied by tobacco product type (e-cigarette or snus) and ad framing (C-F or S-F). The dependent measures for this study were ad-related (ad perceptions, ad credibility) and product-related perceptions (absolute and comparative risk perceptions, product appeal, and product use intentions). Results Former and current smokers rated C-F ads as more persuasive than S-F ads, as evidenced by favorable ad perceptions and high product use intentions. Former and current smokers also rated e-cigarette ads with more favorable ad perceptions, low absolute and comparative risk perceptions, high product appeal, and high product use intentions as compared to snus ads. However, the effect sizes of the significant differences are less than.2, indicating small magnitude of difference between the study variables. Conclusions Unless FDA regulates e-cig and snus advertising, there is a potential of decreasing risk perceptions and increasing use of e-cigs among young adults. Further research on implicit/explicit comparative claims in e-cigarettes and snus advertisements that encourage risk misperceptions is recommended. PMID:28042597

The Effect of Comparatively-Framed versus Similarity-Framed E-Cigarette and Snus Print Ads on Young Adults' Ad and Product Perceptions.

PubMed

Banerjee, Smita C; Greene, Kathryn; Li, Yuelin; Ostroff, Jamie S

2016-07-01

This study examined the effects of comparative-framing [C-F; ads highlighting differences between the advertised product and conventional cigarettes and/or smokeless tobacco products] versus similarity-framing (S-F; ads highlighting congruence with conventional cigarettes and/or smokeless tobacco products) in e-cigarette and snus ads on young adult smokers' and non-smokers' ad- and product-related perceptions. One thousand fifty one (1,051) young adults (18-24 years; 76% women; 50% smokers) from existing consumer panels were recruited in a within-subjects quasi-experiment. Each participant viewed 4 online advertisements, varied by tobacco product type (e-cigarette or snus) and ad framing (C-F or S-F). The dependent measures for this study were ad-related (ad perceptions, ad credibility) and product-related perceptions (absolute and comparative risk perceptions, product appeal, and product use intentions). Former and current smokers rated C-F ads as more persuasive than S-F ads, as evidenced by favorable ad perceptions and high product use intentions. Former and current smokers also rated e-cigarette ads with more favorable ad perceptions, low absolute and comparative risk perceptions, high product appeal, and high product use intentions as compared to snus ads. However, the effect sizes of the significant differences are less than.2, indicating small magnitude of difference between the study variables. Unless FDA regulates e-cig and snus advertising, there is a potential of decreasing risk perceptions and increasing use of e-cigs among young adults. Further research on implicit/explicit comparative claims in e-cigarettes and snus advertisements that encourage risk misperceptions is recommended.

Physicians’ Perceptions of Autonomy across Practice Types: Is Autonomy in Solo Practice a Myth?

PubMed Central

Lin, Katherine Y.

2013-01-01

Physicians in the United States are now less likely to practice in smaller, more traditional, solo practices, and more likely to practice in larger group practices. Though older theory predicts conflict between bureaucracy and professional autonomy, studies have shown that professions in general, and physicians in particular, have adapted to organizational constraints. However, much work remains in clarifying the nature of this relationship and how exactly physicians have adapted to various organizational settings. To this end, the present study examines physicians’ autonomy experiences in different decision types between organization sizes. Specifically, I ask: In what kinds of decisions do doctors perceive autonomous control? How does this vary by organizational size? Using stacked “spell” data constructed from the Community Tracking Study (CTS) Physician Survey (1996–2005) (n=16,519) I examine how physicians’ perceptions of autonomy vary between solo/two physician practices, small group practices with three to ten physicians, and large practices with ten or more physicians, in two kinds of decisions: logistic-based and knowledge-based decisions. Capitalizing on the longitudinal nature of the data I estimate how changes in practice size are associated with perceptions of autonomy, accounting for previous reports of autonomy. I also test whether managed care involvement, practice ownership, and salaried employment help explain part of this relationship. I find that while physicians practicing in larger group practices reported lower levels of autonomy in logistic-based decisions, physicians in solo/two physician practices reported lower levels of autonomy in knowledge-based decisions. Managed care involvement and ownership explain some, but not all, of the associations. These findings suggest that professional adaptation to various organizational settings can lead to varying levels of perceived autonomy across different kinds of decisions. PMID:24444835

The Integrated Care of Asthma in Switzerland (INCAS) Study: Changes in Asthma Control and Perception of Health Care through Asthma Education.

PubMed

Dürr, Selina; Hersberger, Kurt E; Zeller, Andreas; Scheuzger, Jonas; Miedinger, David; Gregoriano, Claudia; Joos Zellweger, Ladina; Steurer-Stey, Claudia; Leuppi, Jörg Daniel

2017-01-01

Despite great efforts in establishing optimal asthma management, asthma may remain uncontrolled. To effectively manage chronic diseases, such as asthma, it is important to train patients in self-management skills. The aim of this study was to assess the potential benefit of standardised asthma education in Switzerland for asthma control and patients' perception of received asthma care and of self-management support. For this multicentre longitudinal controlled study, asthma patients were recruited in Switzerland. The Asthma Control Test (ACT) was used to assess asthma control. The Patient Assessment of Chronic Illness Care questionnaire (PACIC 5A) was applied to evaluate received health-care services and self-management support. Patients were offered the possibility to attend asthma education sessions conducted by the Swiss Lung League and Swiss Allergy Centre. After 1 year, attenders and non-attenders completed the questionnaires again. Changes in ACT and PACIC 5A scores were analysed using dependent t tests. Overall, 223 patients with asthma were investigated (mean age 43 ± 12 years, 38% male, 13% current smokers, 29% ex-smokers). Sixty-one (27%) patients attended education sessions. Both groups had improved asthma control at follow-up (attenders: t(56) = -3.2, r = 0.4 [medium effect size], p = 0.002; non-attenders: t(141) = -2.6, r = 0.2 [small effect size], p = 0.010). Attenders improved in PACIC and 5A sum scores (t(50) = -3.6, r = 0.5 [medium effect size], p = 0.001). A comprehensive self-management asthma education programme in Switzerland improved asthma control and patients' perception of received asthma care and of self-management support. Professionals should motivate patients to attend asthma education in order to become active partners in managing their disease. © 2017 S. Karger AG, Basel.

Physicians' perceptions of autonomy across practice types: Is autonomy in solo practice a myth?

PubMed

Lin, Katherine Y

2014-01-01

Physicians in the United States are now less likely to practice in smaller, more traditional, solo practices, and more likely to practice in larger group practices. Though older theory predicts conflict between bureaucracy and professional autonomy, studies have shown that professions in general, and physicians in particular, have adapted to organizational constraints. However, much work remains in clarifying the nature of this relationship and how exactly physicians have adapted to various organizational settings. To this end, the present study examines physicians' autonomy experiences in different decision types between organization sizes. Specifically, I ask: In what kinds of decisions do doctors perceive autonomous control? How does this vary by organizational size? Using stacked "spell" data constructed from the Community Tracking Study (CTS) Physician Survey (1996-2005) (n = 16,519) I examine how physicians' perceptions of autonomy vary between solo/two physician practices, small group practices with three to ten physicians, and large practices with ten or more physicians, in two kinds of decisions: logistic-based and knowledge-based decisions. Capitalizing on the longitudinal nature of the data I estimate how changes in practice size are associated with perceptions of autonomy, accounting for previous reports of autonomy. I also test whether managed care involvement, practice ownership, and salaried employment help explain part of this relationship. I find that while physicians practicing in larger group practices reported lower levels of autonomy in logistic-based decisions, physicians in solo/two physician practices reported lower levels of autonomy in knowledge-based decisions. Managed care involvement and ownership explain some, but not all, of the associations. These findings suggest that professional adaptation to various organizational settings can lead to varying levels of perceived autonomy across different kinds of decisions. Copyright © 2013 Elsevier Ltd. All rights reserved.

Ambient music in the emergency services: the professionals' perception.

PubMed

Gatti, Maria Fernanda Zorzi; da Silva, Maria Júlia Paes

2007-01-01

Due to the assistant characteristic of the emergency service, the health professional experiences countless situations that generate anxiety. This study aimed to learn the professionals' perception about the presence of classical music in the working environment. The sample was composed of 49 professionals of the adult emergency department of a medium sized private hospital. The data were collected through a questionnaire to evaluate the professional's perception. The results showed that 78% of the professionals noticed alteration in the atmosphere when the music was present, 41% believed that the music altered their personal performance; 85% believed it altered their performance in a positive way and 15% in a negative way. Regarding the musical repertoire, 61% of the individuals affirmed they enjoyed the selection, 96% believed that the ambient music should be kept, while 76% of the interviewees suggested other musical genres.

Illusory Changes in Body Size Modulate Body Satisfaction in a Way That Is Related to Non-Clinical Eating Disorder Psychopathology

PubMed Central

Preston, Catherine; Ehrsson, H. Henrik

2014-01-01

Historically, body size overestimation has been linked to abnormal levels of body dissatisfaction found in eating disorders. However, recently this relationship has been called into question. Indeed, despite a link between how we perceive and how we feel about our body seeming intuitive, until now lack of an experimental method to manipulate body size has meant that a causal link, even in healthy participants, has remained elusive. Recent developments in body perception research demonstrate that the perceptual experience of the body can be readily manipulated using multisensory illusions. The current study exploits such illusions to modulate perceived body size in an attempt to influence body satisfaction. Participants were presented with stereoscopic video images of slimmer and wider mannequin bodies viewed through head-mounted displays from first person perspective. Illusory ownership was induced by synchronously stroking the seen mannequin body with the unseen real body. Pre and post-illusion affective and perceptual measures captured changes in perceived body size and body satisfaction. Illusory ownership of a slimmer body resulted in participants perceiving their actual body as slimmer and giving higher ratings of body satisfaction demonstrating a direct link between perceptual and affective body representations. Change in body satisfaction following illusory ownership of a wider body, however, was related to degree of (non-clinical) eating disorder psychopathology, which can be linked to fluctuating body representations found in clinical samples. The results suggest that body perception is linked to body satisfaction and may be of importance for eating disorder symptomology. PMID:24465698

Size and distance are perceived independently in an optical tunnel: Evidence for direct perception.

PubMed

Kim, Seokhun; Carello, Claudia; Turvey, Michael T

2016-08-01

The historical but questionable size-distance invariance hypothesis (SDIH) features computation over geometric, oculomotor, and binocular cues and the coupling of percepts-perceived size, S', is mediated by perceived distance, D'. A contemporary non-mediational hypothesis holds that S' and D' are specific to distinct optical variables. We report two experiments with an optical tunnel, an arrangement of alternating black and white concentric rings, that allows systematic manipulation of the optic array at a point of observation while controlling a variety of size and depth cues. Participants viewed targets of different sizes at different distances monocularly, reporting S' and D' via magnitude production. In Experiment 1, the target was either placed in a continuous tunnel (extending 164cm) or in a tunnel that truncated at the target's location. Experiment 2 included a third tunnel, one that was truncated with a flat depiction of the posterior surface structure that would have been visible in the continuous tunnel. In both experiments, S' decreased with D but D' was unaffected by S. Partial correlation analyses showed that the relationship between S' and D' was not significant when the contributions of other variables were removed. Importantly, S' and D' were affected differently by manipulations of the optical tunnel's continuity while computationally obvious visual cues were controlled. These outcomes suggest that D' is not a mediator of S'. Rather S' and D' are independently determined with correlated but different optical bases, results that support the direct model. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ensemble representations: effects of set size and item heterogeneity on average size perception.

PubMed

Marchant, Alexander P; Simons, Daniel J; de Fockert, Jan W

2013-02-01

Observers can accurately perceive and evaluate the statistical properties of a set of objects, forming what is now known as an ensemble representation. The accuracy and speed with which people can judge the mean size of a set of objects have led to the proposal that ensemble representations of average size can be computed in parallel when attention is distributed across the display. Consistent with this idea, judgments of mean size show little or no decrement in accuracy when the number of objects in the set increases. However, the lack of a set size effect might result from the regularity of the item sizes used in previous studies. Here, we replicate these previous findings, but show that judgments of mean set size become less accurate when set size increases and the heterogeneity of the item sizes increases. This pattern can be explained by assuming that average size judgments are computed using a limited capacity sampling strategy, and it does not necessitate an ensemble representation computed in parallel across all items in a display. Copyright © 2012 Elsevier B.V. All rights reserved.

Pyramid algorithms as models of human cognition

NASA Astrophysics Data System (ADS)

Pizlo, Zygmunt; Li, Zheng

2003-06-01

There is growing body of experimental evidence showing that human perception and cognition involves mechanisms that can be adequately modeled by pyramid algorithms. The main aspect of those mechanisms is hierarchical clustering of information: visual images, spatial relations, and states as well as transformations of a problem. In this paper we review prior psychophysical and simulation results on visual size transformation, size discrimination, speed-accuracy tradeoff, figure-ground segregation, and the traveling salesman problem. We also present our new results on graph search and on the 15-puzzle.

Gaze anchoring guides real but not pantomime reach-to-grasp: support for the action-perception theory.

PubMed

Kuntz, Jessica R; Karl, Jenni M; Doan, Jon B; Whishaw, Ian Q

2018-04-01

Reach-to-grasp movements feature the integration of a reach directed by the extrinsic (location) features of a target and a grasp directed by the intrinsic (size, shape) features of a target. The action-perception theory suggests that integration and scaling of a reach-to-grasp movement, including its trajectory and the concurrent digit shaping, are features that depend upon online action pathways of the dorsal visuomotor stream. Scaling is much less accurate for a pantomime reach-to-grasp movement, a pretend reach with the target object absent. Thus, the action-perception theory proposes that pantomime movement is mediated by perceptual pathways of the ventral visuomotor stream. A distinguishing visual feature of a real reach-to-grasp movement is gaze anchoring, in which a participant visually fixates the target throughout the reach and disengages, often by blinking or looking away/averting the head, at about the time that the target is grasped. The present study examined whether gaze anchoring is associated with pantomime reaching. The eye and hand movements of participants were recorded as they reached for a ball of one of three sizes, located on a pedestal at arms' length, or pantomimed the same reach with the ball and pedestal absent. The kinematic measures for real reach-to-grasp movements were coupled to the location and size of the target, whereas the kinematic measures for pantomime reach-to-grasp, although grossly reflecting target features, were significantly altered. Gaze anchoring was also tightly coupled to the target for real reach-to-grasp movements, but there was no systematic focus for gaze, either in relation with the virtual target, the previous location of the target, or the participant's reaching hand, for pantomime reach-to-grasp. The presence of gaze anchoring during real vs. its absence in pantomime reach-to-grasp supports the action-perception theory that real, but not pantomime, reaches are online visuomotor actions and is discussed in relation with the neural control of real and pantomime reach-to-grasp movements.

Blended-Learning Pain Neuroscience Education for People With Chronic Spinal Pain: Randomized Controlled Multicenter Trial.

PubMed

Malfliet, Anneleen; Kregel, Jeroen; Meeus, Mira; Roussel, Nathalie; Danneels, Lieven; Cagnie, Barbara; Dolphens, Mieke; Nijs, Jo

2018-05-01

Available evidence favors the use of pain neuroscience education (PNE) in patients with chronic pain. However, PNE trials are often limited to small sample sizes and, despite the current digital era, the effects of blended-learning PNE (ie, the combination of online digital media with traditional educational methods) have not yet been investigated. The study objective was to examine whether blended-learning PNE is able to improve disability, catastrophizing, kinesiophobia, and illness perceptions. This study was a 2-center, triple-blind randomized controlled trial (participants, statistician, and outcome assessor were masked). The study took place at university hospitals in Ghent and Brussels, Belgium. Participants were 120 people with nonspecific chronic spinal pain (ie, chronic neck pain and low back pain). The intervention was 3 sessions of PNE or biomedically focused back/neck school education (addressing spinal anatomy and physiology). Measurements were self-report questionnaires (Pain Disability Index, Pain Catastrophizing Scale, Tampa Scale for Kinesiophobia, Illness Perception Questionnaire, and Pain Vigilance and Awareness Questionnaire). None of the treatment groups showed a significant change in the perceived disability (Pain Disability Index) due to pain (mean group difference posteducation: 1.84; 95% CI = -2.80 to 6.47). Significant interaction effects were seen for kinesiophobia and several subscales of the Illness Perception Questionnaire, including negative consequences, cyclical time line, and acute/chronic time line. In-depth analysis revealed that only in the PNE group were these outcomes significantly improved (9% to 17% improvement; 0.37 ≤ Cohen d ≥ 0.86). Effect sizes are small to moderate, which might raise the concern of limited clinical utility; however, changes in kinesiophobia exceed the minimal detectable difference. PNE should not be used as the sole treatment modality but should be combined with other treatment strategies. Blended-learning PNE was able to improve kinesiophobia and illness perceptions in participants with chronic spinal pain. As effect sizes remained small to medium, PNE should not be used as a sole treatment but rather should be used as a key element within a comprehensive active rehabilitation program. Future studies should compare the effects of blended-learning PNE with offline PNE and should consider cost-effectiveness.

Inexpensive Animal Learning Exercises for Huge Introductory Laboratory Classes

ERIC Educational Resources Information Center

Katz, Albert N.

1978-01-01

Suggests use of the planarian D. Dorotocephala, an animal 20 mm in size, in order to provide inexpensive lab experiences for students in large introductory psychology courses. The animal can be used to study perception, memory, behavior modification, and group processes. (Author/AV)

Adolescent Athleticism, Exercise, Body Image, and Dietary Practices.

ERIC Educational Resources Information Center

Rainey, Cheryl J.; McKeown, Robert E.; Sargent, Roger G.; Valois, Robert F.

1998-01-01

Investigated relationships between physical activity and athletic participation and body-size perceptions, diet, and weight-control practice among high school students, noting racial and gender differences. Surveys indicated that diet quality improved and weight-loss attempts increased as physical activity and athletic participation increased.…

Realistic weight perception and body size assessment in a racially diverse community sample of dieters.

PubMed

Cachelin, F M; Striegel-Moore, R H; Elder, K A

1998-01-01

Recently, a shift in obesity treatment away from emphasizing ideal weight loss goals to establishing realistic weight loss goals has been proposed; yet, what constitutes "realistic" weight loss for different populations is not clear. This study examined notions of realistic shape and weight as well as body size assessment in a large community-based sample of African-American, Asian, Hispanic, and white men and women. Participants were 1893 survey respondents who were all dieters and primarily overweight. Groups were compared on various variables of body image assessment using silhouette ratings. No significant race differences were found in silhouette ratings, nor in perceptions of realistic shape or reasonable weight loss. Realistic shape and weight ratings by both women and men were smaller than current shape and weight but larger than ideal shape and weight ratings. Compared with male dieters, female dieters considered greater weight loss to be realistic. Implications of the findings for the treatment of obesity are discussed.

Modeling of Depth Cue Integration in Manual Control Tasks

NASA Technical Reports Server (NTRS)

Sweet, Barbara T.; Kaiser, Mary K.; Davis, Wendy

2003-01-01

Psychophysical research has demonstrated that human observers utilize a variety of visual cues to form a perception of three-dimensional depth. However, most of these studies have utilized a passive judgement paradigm, and failed to consider depth-cue integration as a dynamic and task-specific process. In the current study, we developed and experimentally validated a model of manual control of depth that examines how two potential cues (stereo disparity and relative size) are utilized in both first- and second-order active depth control tasks. We found that stereo disparity plays the dominate role for determining depth position, while relative size dominates perception of depth velocity. Stereo disparity also plays a reduced role when made less salient (i.e., when viewing distance is increased). Manual control models predict that position information is sufficient for first-order control tasks, while velocity information is required to perform a second-order control task. Thus, the rules for depth-cue integration in active control tasks are dependent on both task demands and cue quality.

Parents perception of weight status of Mexican preschool children using different tools.

PubMed

Souto-Gallardo, M C; Jiménez-Cruz, A; Bacardí-Gascón, M

2011-12-01

The aim of this study was to evaluate the ability of parents to estimate the weight status of preschool children attending the Instituto Mexicano del Seguro Social (IMSS) day-care centers using three different tools. A total of 100 parent-child pairs attending to all the existing IMSS day-care centers in Ensenada (n = 9) completed a questionnaire on the perception of children's weight status using verbal description, sketches, and pictures. Chi squared test and univariate logistic regression was applied to assess the difference in perception between the tools used, the factors associated with the weight status perception and to identify predictors of parental underestimation of their child's weight. The sample size was estimated for a significance level of 0.05 with statistical power of 80%. No significant differences were found in the perception of weight status using different tools. The parents' underestimation of the child's weight status ranged from 51 to 59%, this percentage jumps to 79 to 84% in overweight children and 82 to 91% in obese children. Being a young mother and having a daughter increased the risk of underestimation. Higher odds of underestimation were found in > 2BMI z-score. The high underestimation found in this study shows that the ability of parents in signaling an alert to prevent childhood obesity might be highly reduced and preventive health programs should include increasing the weight status perception.

The influence of pain-related expectations on intensity perception of non-painful somatosensory stimuli.

PubMed

Zaman, Jonas; Wiech, Katja; Claes, Nathalie; Van Oudenhove, Lukas; Van Diest, Ilse; Vlaeyen, Johan W S

2018-04-03

The extent to which pain-related expectations, known to affect pain perception, also affect perception of non-painful sensations remains unclear, as well as the potential role of unpredictability in this context. In a proprioceptive fear conditioning paradigm, various arm extension movements were associated with predictable and unpredictable electrocutaneous pain or its absence. During a subsequent test phase non-painful electrocutaneous stimuli with a high or low intensity were presented during movement execution. We used hierarchical drift diffusion modeling to examine the influence of expecting pain on the perceptual decision-making process underlying intensity perception of non-painful sensations. In the first experiment (n=36), the pain stimulus was never presented during the test phase after conditioning. In the second experiment (n=39), partial reinforcement was adopted to prevent extinction of pain expectations. In both experiments, movements that were associated with (un)predictable pain led to higher pain-expectancy, self-reported fear, unpleasantness and arousal, as compared to movements that were never paired with pain (effect sizes ηp ranging from .119 - .557; all p-values < .05). Only in the second experiment - when the threat of the pain US remained present - we found that the expectation of pain affected decision-making. Compared to the no pain condition, an a priori decision-making bias towards the high intensity decision threshold was found with the strongest bias during unpredictable pain (effect sizes ηp ranging from .469 - .504; all p-values < .001). Thus, the expectation of pain not only affects inferential processes for subsequent painful but also for non-painful bodily stimuli, with unpredictability moderating these effects, and only when the threat of pain remains present due to partial reinforcement.

Gestalt-like constraints produce veridical (Euclidean) percepts of 3D indoor scenes

PubMed Central

Kwon, TaeKyu; Li, Yunfeng; Sawada, Tadamasa; Pizlo, Zygmunt

2015-01-01

This study, which was influenced a lot by Gestalt ideas, extends our prior work on the role of a priori constraints in the veridical perception of 3D shapes to the perception of 3D scenes. Our experiments tested how human subjects perceive the layout of a naturally-illuminated indoor scene that contains common symmetrical 3D objects standing on a horizontal floor. In one task, the subject was asked to draw a top view of a scene that was viewed either monocularly or binocularly. The top views the subjects reconstructed were configured accurately except for their overall size. These size errors varied from trial to trial, and were shown most-likely to result from the presence of a response bias. There was little, if any, evidence of systematic distortions of the subjects’ perceived visual space, the kind of distortions that have been reported in numerous experiments run under very unnatural conditions. This shown, we proceeded to use Foley’s (Vision Research 12 (1972) 323–332) isosceles right triangle experiment to test the intrinsic geometry of visual space directly. This was done with natural viewing, with the impoverished viewing conditions Foley had used, as well as with a number of intermediate viewing conditions. Our subjects produced very accurate triangles when the viewing conditions were natural, but their performance deteriorated systematically as the viewing conditions were progressively impoverished. Their perception of visual space became more compressed as their natural visual environment was degraded. Once this was shown, we developed a computational model that emulated the most salient features of our psychophysical results. We concluded that human observers see 3D scenes veridically when they view natural 3D objects within natural 3D environments. PMID:26525845

Patient’s Perception of Nursing Care at a Large Teaching Hospital in India

PubMed Central

Samina, Mufti; GJ, Qadri; Tabish, SA; Samiya, Mufti; Riyaz, R

2008-01-01

Background: As focus has shifted from the healthcare providers to the healthcare consumers; patient satisfaction is being increasingly used worldwide for the assessment of quality of services provided by healthcare institutions. To understand patient satisfaction, “patient’s perception” of care must first be understood. Of all the healthcare workers nurses spend maximum time with the patients. Therefore, the nurse is in a unique position to influence and promote effective consumer relationships. Though patient satisfaction surveys with nursing care are routinely conducted in the developed world to monitor and improve the quality of care, the same is not true for the developing world especially in the Indian subcontinent. Objective: To conduct a study of patient’s perception of nursing care in a large teaching hospital. Methods: A prospective study spread over a period of one year was carried out. Sample size consisted of seven percent of patients each admitted as emergency and routine. All the randomly selected patients were administered questionnaires, thus obtaining a sample size of 2600. Of these 2500 questionnaires were usable for data analysis (valid response rate of 81.6%). Results: The results of the study revealed a relatively higher percentage of patients with poor perception regarding ‘explanation and information’, and ‘caring attitude’ aspects of nursing care (31.6% and 11.5% respectively). However more than 95% patients had good perception of ‘responsiveness’, ‘availability’ and ‘ward organization’ capability of the nurse. Conclusion: Patient satisfaction surveys should become a regular outcome monitoring feature in all the hospitals. Also In-service training programs for nurses, with special emphasis on communication are need of the hour and should become a regular exercise. PMID:21475490

How much does what you eat matter? The potential role of meal size, fat content, and gender on ratings of desirability.

PubMed

Yantcheva, B; Brindal, E

2013-08-01

This study examined how the amount and type of food that a person eats affects perceptions of their personal desirability, femininity/masculinity, and body size while accounting for any assumed similarity biases. Female students (18 to 59 years old) were recruited through the School of Psychology at the University of Adelaide. Participants (n = 191) rated the characteristics of a fictional person based on information in a personal profile. Profiles were identical aside from experimental manipulations of gender (male/female), meal size (small/large) and meal type (regular fat/high fat) with meal manipulations calculated using nutrient recommendations. Ratings of desirability and body size were affected primarily by meal type with targets described as eating a regular fat meal seen as more desirable (M = 5.40, SD = 0.56) and thinner (M = 3.93, SD = 1.05) than those having a high fat meal (M = 5.09, SD = 0.66; M = 4.29, SD = 1.04) (p = .001). Meal size manipulations affected only ratings of body size with larger meals (M = 4.25, SD = 0.88) resulting in higher ratings relative to smaller meals (M = 3.96, SD = 1.20) (p = .036). Despite a suggestion of interactions between target gender and both meal characteristics for ratings of femininity/masculinity in our results, post-hoc analyses largely failed to reveal any pairwise differences. Perceived similarity to the target did relate to levels of desirability (p = .006), and self-esteem positively associated with ratings of target body size (p = .010). Even though men's perceptions of eating behaviours were not reported in this paper, these findings have implications for a better understanding of social pressures faced not only by women, but also for men, as potentially both genders may be affected by eating norms regarding the healthiness of a meal. Copyright © 2013 Elsevier Ltd. All rights reserved.

Top-down control of visual perception: attention in natural vision.

PubMed

Rolls, Edmund T

2008-01-01

Top-down perceptual influences can bias (or pre-empt) perception. In natural scenes, the receptive fields of neurons in the inferior temporal visual cortex (IT) shrink to become close to the size of objects. This facilitates the read-out of information from the ventral visual system, because the information is primarily about the object at the fovea. Top-down attentional influences are much less evident in natural scenes than when objects are shown against blank backgrounds, though are still present. It is suggested that the reduced receptive-field size in natural scenes, and the effects of top-down attention contribute to change blindness. The receptive fields of IT neurons in complex scenes, though including the fovea, are frequently asymmetric around the fovea, and it is proposed that this is the solution the IT uses to represent multiple objects and their relative spatial positions in a scene. Networks that implement probabilistic decision-making are described, and it is suggested that, when in perceptual systems they take decisions (or 'test hypotheses'), they influence lower-level networks to bias visual perception. Finally, it is shown that similar processes extend to systems involved in the processing of emotion-provoking sensory stimuli, in that word-level cognitive states provide top-down biasing that reaches as far down as the orbitofrontal cortex, where, at the first stage of affective representations, olfactory, taste, flavour, and touch processing is biased (or pre-empted) in humans.

Educators' Perceptions of Automated Feedback Systems

ERIC Educational Resources Information Center

Debuse, Justin C. W.; Lawley, Meredith; Shibl, Rania

2008-01-01

Assessment of student learning is a core function of educators. Ideally students should be provided with timely, constructive feedback to facilitate learning. However, provision of high quality feedback becomes more complex as class sizes increase, modes of study expand and academic workloads increase. ICT solutions are being developed to…

Seeing the Body Distorts Tactile Size Perception

ERIC Educational Resources Information Center

Longo, Matthew R.; Sadibolova, Renata

2013-01-01

Vision of the body modulates somatosensation, even when entirely non-informative about stimulation. For example, seeing the body increases tactile spatial acuity, but reduces acute pain. While previous results demonstrate that vision of the body modulates somatosensory sensitivity, it is unknown whether vision also affects metric properties of…

Student Perception of Academic Achievement Factors at High School

ERIC Educational Resources Information Center

Bahar, Mustafa

2016-01-01

Measuring the quality of the "product" is elemental in education, and most studies depend on observational data about student achievement factors, focusing overwhelmingly on quantitative data namely achievement scores, school data like attendance, facilities, expenditure class size, etc. But there is little evidence of learner…

Community Size, Perceptions of Majority Opinion and Opinion Expression.

ERIC Educational Resources Information Center

Salmon, Charles T.; Oshagan, Hayg

A study examined structural determinants of opinion expression by merging two theoretical perspectives: the "spiral of silence" model advanced by Elisabeth Noelle-Neumann, and the structural approach to communication research offered by Phillip Tichenor, George Donohue, and Clarice Olien. The study also distinguished between different…

Multicompetent Health Professionals: Needs, Combinations, and Curriculum Development.

ERIC Educational Resources Information Center

Beachey, Will

1988-01-01

Presents results from surveys of health professions alumni (n=320) and hospital administrators (n=80) that revealed a perception of need for multicompetency regardless of hospital size or profession, particularly such combinations as medical technology/radiology technology, nursing/respiratory therapy, and physical therapy/occupational therapy.…

Healthcare service quality perception in Japan.

PubMed

Eleuch, Amira ep Koubaa

2011-01-01

This study aims to assess Japanese patients' healthcare service quality perceptions and to shed light on the most meaningful service features. It follows-up a study published in IJHCQA Vol. 21 No. 7. Through a non-linear approach, the study relied on the scatter model to detect healthcare service features' importance in forming overall quality judgment. Japanese patients perceive healthcare services through a linear compensatory process. Features related to technical quality and staff behavior compensate for each other to decide service quality. A limitation of the study is the limited sample size. Non-linear approaches could help researchers to better understand patients' healthcare service quality perceptions. The study highlights a need to adopt an evolution that enhances technical quality and medical practices in Japanese healthcare settings. The study relies on a non-linear approach to assess patient overall quality perceptions in order to enrich knowledge. Furthermore, the research is conducted in Japan where healthcare marketing studies are scarce owing to cultural and language barriers. Japanese culture and healthcare system characteristics are used to explain and interpret the results.

Development of a new body image assessment scale in urban Cameroon: an anthropological approach.

PubMed

Cohen, Emmanuel; Pasquet, Patrick

2011-01-01

Develop and validate body image scales (BIS) presenting real human bodies adapted to the macroscopic phenotype of urban Cameroonian populations. Quantitative and qualitative analysis. Yaoundé, capital city of Cameroon. Four samples with balanced sex-ratio: the first (n=16) aged 18 to 65 years (qualitative study), the second (n=30) aged 25 to 40 years (photo database), the third (n=47) and fourth (n=181), > or =18 years (validation study). Construct validity, test retest reliability, concurrent and convergent validity of BIS. Body image scales present six Cameroonians of each sex arranged according to main body mass index (BMI) categories: underweight (<18.5 kg/m2), normal (18.5-24.9 kg/m2), overweight (25-29.9 kg/m2), obesity class I (30-34.9 kg/m2), obesity class II (35-39.9 kg/m2), and obesity class III (> or =40 kg/m2). Test-retest reliability correlations for current body size (CBS), desired body size and current desirable discrepancy (body self-satisfaction index) on BIS were never below .90. Plus, for the concurrent validity, we observed a significant correlation (r=0.67, P<.01) between measured BMI and CBS. Finally, the convergent validity between BIS and a female African American silhouettes scale, for different dimensions of body size perceptions, is acceptable. Body image scales are adapted to the phenotypic characteristics of urban Cameroonian populations. They are reliable and valid to assess body size perceptions and culturally adapted to the Cameroonian context.

Preferred child body size and parental underestimation of child weight in Mexican American families

PubMed Central

Pasch, Lauri A.; Penilla, Carlos; Tschann, Jeanne M.; Martinez, Suzanna M.; Deardorff, Julianna; de Groat, Cynthia L.; Gregorich, Steven E.; Flores, Elena; Butte, Nancy F.; Greenspan, Louise C.

2016-01-01

Objective To determine whether parents who prefer a heavier child would underestimate their child's weight more than those who prefer a leaner child. Methods Participants were Mexican American families (312 mothers, 173 fathers, and 312 children ages 8-10) who were interviewed and had height and weight measurements. Parents reported their preferred child body size and their perceptions of their child's weight. Parents’ underestimation of their child's weight was calculated as the standardized difference between parent's perception of their child's weight and the child's body mass index (BMI) z-score. Demographic factors and parental BMI were also assessed. Results Although 50% of children were overweight or obese, only 11% of mothers and 10% of fathers perceived their children as being somewhat or very overweight. Multiple regressions controlling for covariates (parental BMI and child age) showed that parents who preferred a heavier child body size underestimated their children's weight more, compared to those who preferred a leaner child (β for mothers = .13, p < .03; (β for fathers = .17, p < .03). Conclusions for Practice Parents who preferred a heavier child body size underestimated their child's weight to a greater degree than parents who preferred a leaner child. Attempts by pediatricians to correct parents’ misperceptions about child weight may damage rapport and ultimately fail if the misperception is actually a reflection of parents’ preferences, which may not be readily amenable to change. Future research should address optimal methods of communication about child overweight which take into account parent preferences. PMID:27016351

Small numbers are sensed directly, high numbers constructed from size and density.

PubMed

Zimmermann, Eckart

2018-04-01

Two theories compete to explain how we estimate the numerosity of visual object sets. The first suggests that the apparent numerosity is derived from an analysis of more low-level features like size and density of the set. The second theory suggests that numbers are sensed directly. Consistent with the latter claim is the existence of neurons in parietal cortex which are specialized for processing the numerosity of elements in the visual scene. However, recent evidence suggests that only low numbers can be sensed directly whereas the perception of high numbers is supported by the analysis of low-level features. Processing of low and high numbers, being located at different levels of the neural hierarchy should involve different receptive field sizes. Here, I tested this idea with visual adaptation. I measured the spatial spread of number adaptation for low and high numerosities. A focused adaptation spread of high numerosities suggested the involvement of early neural levels where receptive fields are comparably small and the broad spread for low numerosities was consistent with processing of number neurons which have larger receptive fields. These results provide evidence for the claim that different mechanism exist generating the perception of visual numerosity. Whereas low numbers are sensed directly as a primary visual attribute, the estimation of high numbers however likely depends on the area size over which the objects are spread. Copyright © 2017 Elsevier B.V. All rights reserved.

Ensemble perception in autism spectrum disorder: Member-identification versus mean-discrimination.

PubMed

Van der Hallen, Ruth; Lemmens, Lisa; Steyaert, Jean; Noens, Ilse; Wagemans, Johan

2017-07-01

To efficiently represent the outside world our brain compresses sets of similar items into a summarized representation, a phenomenon known as ensemble perception. While most studies on ensemble perception investigate this perceptual mechanism in typically developing (TD) adults, more recently, researchers studying perceptual organization in individuals with autism spectrum disorder (ASD) have turned their attention toward ensemble perception. The current study is the first to investigate the use of ensemble perception for size in children with and without ASD (N = 42, 8-16 years). We administered a pair of tasks pioneered by Ariely [2001] evaluating both member-identification and mean-discrimination. In addition, we varied the distribution types of our sets to allow a more detailed evaluation of task performance. Results show that, overall, both groups performed similarly in the member-identification task, a test of "local perception," and similarly in the mean identification task, a test of "gist perception." However, in both tasks performance of the TD group was affected more strongly by the degree of stimulus variability in the set, than performance of the ASD group. These findings indicate that both TD children and children with ASD use ensemble statistics to represent a set of similar items, illustrating the fundamental nature of ensemble coding in visual perception. Differences in sensitivity to stimulus variability between both groups are discussed in relation to recent theories of information processing in ASD (e.g., increased sampling, decreased priors, increased precision). Autism Res 2017. © 2017 International Society for Autism Research, Wiley Periodicals, Inc. Autism Res 2017, 10: 1291-1299. © 2017 International Society for Autism Research, Wiley Periodicals, Inc. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

Hazard perception skills of young drivers with Attention Deficit Hyperactivity Disorder (ADHD) can be improved with computer based driver training: An exploratory randomised controlled trial.

PubMed

Bruce, C R; Unsworth, C A; Dillon, M P; Tay, R; Falkmer, T; Bird, P; Carey, L M

2017-12-01

Young drivers with Attention Deficit Hyperactivity Disorder (ADHD) are at higher risk of road traffic injuries than their peers. Increased risk correlates with poor hazard perception skill. Few studies have investigated hazard perception training using computer technology with this group of drivers. *Determine the presence and magnitude of the between-group and within- subject change in hazard perception skills in young drivers with ADHD who receive Drive Smart training. *Determine whether training-facilitated change in hazard perception is maintained over time. This was a feasibility study, randomised control trial conducted in Australia. The design included a delayed treatment for the control group. Twenty-five drivers with a diagnosis of ADHD were randomised to the Immediate Intervention or Delayed Intervention group.The Immediate Intervention group received a training session using a computer application entitled Drive Smart. The Delayed Intervention group watched a documentary video initially (control condition), followed by the Drive Smart computer training session. The participant's hazard perception skill was measured using the Hazard Perception Test (HPT). After adjusting for baseline scores, there was a significant betweengroup difference in post-intervention HPT change scores in favour of the Immediate Intervention group. The magnitude of the effect was large. There was no significant within-group delayed intervention effect. A significant maintenance effect was found at 6-week follow-up for the Immediate Intervention group. The hazard perception skills of participants improved following training with large effect size and some maintenance of gain. A multimodal approach to training is indicated to facilitate maintenance. A full-scale trial is feasible. Copyright © 2017 Elsevier Ltd. All rights reserved.

Rationality, perception, and the all-seeing eye.

PubMed

Felin, Teppo; Koenderink, Jan; Krueger, Joachim I

2017-08-01

Seeing-perception and vision-is implicitly the fundamental building block of the literature on rationality and cognition. Herbert Simon and Daniel Kahneman's arguments against the omniscience of economic agents-and the concept of bounded rationality-depend critically on a particular view of the nature of perception and vision. We propose that this framework of rationality merely replaces economic omniscience with perceptual omniscience. We show how the cognitive and social sciences feature a pervasive but problematic meta-assumption that is characterized by an "all-seeing eye." We raise concerns about this assumption and discuss different ways in which the all-seeing eye manifests itself in existing research on (bounded) rationality. We first consider the centrality of vision and perception in Simon's pioneering work. We then point to Kahneman's work-particularly his article "Maps of Bounded Rationality"-to illustrate the pervasiveness of an all-seeing view of perception, as manifested in the extensive use of visual examples and illusions. Similar assumptions about perception can be found across a large literature in the cognitive sciences. The central problem is the present emphasis on inverse optics-the objective nature of objects and environments, e.g., size, contrast, and color. This framework ignores the nature of the organism and perceiver. We argue instead that reality is constructed and expressed, and we discuss the species-specificity of perception, as well as perception as a user interface. We draw on vision science as well as the arts to develop an alternative understanding of rationality in the cognitive and social sciences. We conclude with a discussion of the implications of our arguments for the rationality and decision-making literature in cognitive psychology and behavioral economics, along with suggesting some ways forward.

Critical examination of the uniformity requirements for single-photon emission computed tomography.

PubMed

O'Connor, M K; Vermeersch, C

1991-01-01

It is generally recognized that single-photon emission computed tomography (SPECT) imposes very stringent requirements on gamma camera uniformity to prevent the occurrence of ring artifacts. The purpose of this study was to examine the relationship between nonuniformities in the planar data and the magnitude of the consequential ring artifacts in the transaxial data, and how the perception of these artifacts is influenced by factors such as reconstruction matrix size, reconstruction filter, and image noise. The study indicates that the relationship between ring artifact magnitude and image noise is essentially independent of the acquisition or reconstruction matrix sizes, but is strongly dependent upon the type of smoothing filter applied during the reconstruction process. Furthermore, the degree to which a ring artifact can be perceived above image noise is dependent on the size and location of the nonuniformity in the planar data, with small nonuniformities (1-2 pixels wide) close to the center of rotation being less perceptible than those further out (8-20 pixels). Small defects or nonuniformities close to the center of rotation are thought to cause the greatest potential corruption to tomographic data. The study indicates that such may not be the case. Hence the uniformity requirements for SPECT may be less demanding than was previously thought.

Equal-magnitude size-weight illusions experienced within and between object categories.

PubMed

Buckingham, Gavin; Goodale, Melvyn A; White, Justin A; Westwood, David A

2016-01-01

In the size-weight illusion (SWI), small objects feel heavier than larger objects of the same mass. This effect is typically thought to be a consequence of the lifter's expectation that the large object will outweigh the small object, because objects of the same type typically get heavier as they get larger. Here, we show that this perceptual effect can occur across object category, where there are no strong expectations about the correspondence between size and mass. One group of participants lifted same-colored large and small cubes with the same mass as one another, while another group lifted differently-colored large and small cubes with the same mass as one another. The group who lifted the same-colored cubes experienced a robust SWI and initially lifted the large object with more force than the small object. By contrast, the group who lifted the different-colored objects did so with equal initial forces on the first trial, but experienced just as strong an illusion as those who lifted the same-colored objects. These results demonstrate that color cues can selectively influence the application of fingertip force rates while not impacting at all upon the lifter's perception of object weight, highlighting a stark dissociation in how prior information affects perception and action.

Virtual reality hardware and graphic display options for brain-machine interfaces

PubMed Central

Marathe, Amar R.; Carey, Holle L.; Taylor, Dawn M.

2009-01-01

Virtual reality hardware and graphic displays are reviewed here as a development environment for brain-machine interfaces (BMIs). Two desktop stereoscopic monitors and one 2D monitor were compared in a visual depth discrimination task and in a 3D target-matching task where able-bodied individuals used actual hand movements to match a virtual hand to different target hands. Three graphic representations of the hand were compared: a plain sphere, a sphere attached to the fingertip of a realistic hand and arm, and a stylized pacman-like hand. Several subjects had great difficulty using either stereo monitor for depth perception when perspective size cues were removed. A mismatch in stereo and size cues generated inappropriate depth illusions. This phenomenon has implications for choosing target and virtual hand sizes in BMI experiments. Target matching accuracy was about as good with the 2D monitor as with either 3D monitor. However, users achieved this accuracy by exploring the boundaries of the hand in the target with carefully controlled movements. This method of determining relative depth may not be possible in BMI experiments if movement control is more limited. Intuitive depth cues, such as including a virtual arm, can significantly improve depth perception accuracy with or without stereo viewing. PMID:18006069

Putting Like a Pro: The Role of Positive Contagion in Golf Performance and Perception

PubMed Central

Lee, Charles; Linkenauger, Sally A.; Bakdash, Jonathan Z.; Joy-Gaba, Jennifer A.; Profitt, Dennis R.

2011-01-01

Many amateur athletes believe that using a professional athlete's equipment can improve their performance. Such equipment can be said to be affected with positive contagion, which refers to the belief of transference of beneficial properties between animate persons/objects to previously neutral objects. In this experiment, positive contagion was induced by telling participants in one group that a putter previously belonged to a professional golfer. The effect of positive contagion was examined for perception and performance in a golf putting task. Individuals who believed they were using the professional golfer's putter perceived the size of the golf hole to be larger than golfers without such a belief and also had better performance, sinking more putts. These results provide empirical support for anecdotes, which allege that using objects with positive contagion can improve performance, and further suggest perception can be modulated by positive contagion. PMID:22028804

Solar Stimulus: Perceptions of banks and credit unions towards solar loans in Massachusetts

NASA Astrophysics Data System (ADS)

Bahirwani, Suveer

Access to finance for residential solar photovoltaic systems (PV) is an essential element of the clean energy economy. Perceptions about solar PV and solar loans among lenders at banks and credit unions shape the availability of lending products for residential solar PV. In March 2015, interviews were carried out among select informants and subsequently, between April and May 2015, a survey was conducted to gauge the perceptions of lenders in Massachusetts. Lenders have a range of concerns with the market and the provision of solar loans. These concerns can be grouped around risk, market size or viability and policy uncertainty. In summary, lending for this segment is not a priority for banks and credit unions in Massachusetts at this time. Recommendations are offered for the lending community and policymakers to improve adoption. Questions for further research are also presented.

Analysis of perceived risk among construction workers: a cross-cultural study and reflection on the Hofstede model.

PubMed

Martinez-Fiestas, Myriam; Rodríguez-Garzón, Ignacio; Delgado-Padial, Antonio; Lucas-Ruiz, Valeriano

2017-09-01

This article presents a cross-cultural study on perceived risk in the construction industry. Worker samples from three different countries were studied: Spain, Peru and Nicaragua. The main goal was to explain how construction workers perceive their occupational hazard and to analyze how this is related to their national culture. The model used to measure perceived risk was the psychometric paradigm. The results show three very similar profiles, indicating that risk perception is independent of nationality. A cultural analysis was conducted using the Hofstede model. The results of this analysis and the relation to perceived risk showed that risk perception in construction is independent of national culture. Finally, a multiple lineal regression analysis was conducted to determine what qualitative attributes could predict the global quantitative size of risk perception. All of the findings have important implications regarding the management of safety in the workplace.

Cultural differences in room size perception

PubMed Central

Bülthoff, Heinrich H.; de la Rosa, Stephan; Dodds, Trevor J.

2017-01-01

Cultural differences in spatial perception have been little investigated, which gives rise to the impression that spatial cognitive processes might be universal. Contrary to this idea, we demonstrate cultural differences in spatial volume perception of computer generated rooms between Germans and South Koreans. We used a psychophysical task in which participants had to judge whether a rectangular room was larger or smaller than a square room of reference. We systematically varied the room rectangularity (depth to width aspect ratio) and the viewpoint (middle of the short wall vs. long wall) from which the room was viewed. South Koreans were significantly less biased by room rectangularity and viewpoint than their German counterparts. These results are in line with previous notions of general cognitive processing strategies being more context dependent in East Asian societies than Western ones. We point to the necessity of considering culturally-specific cognitive processing strategies in visual spatial cognition research. PMID:28426729

Home activity programs in families with children presenting with global developmental delays: evaluation and parental perceptions.

PubMed

Tétreault, Sylvie; Parrot, Ann; Trahan, Johanne

2003-09-01

The present study presents a descriptive evaluation of home activity programs (HAP) in families living with a child diagnosed with global developmental delay (GDD) and investigates parental perceptions about the use of HAPs. Forty-one families were selected from an initial pool of 95. Application of the HAP--delivered by an occupational therapist, physical therapist or speech therapist--was evaluated via a telephone survey. Data about parental perceptions of the HAP was collected. The results indicate a high degree of compliance with the program; 31 families were still using the HAP after 7 months. The degree of compliance is dependent on the degree of support given by the therapist and on the size of the family and many parents who maintained high compliance seemed to be those most vulnerable to stress. When giving out HAPs, therapists should be aware of the great demands they place on mothers.

Social cognition intervention in schizophrenia: Description of the training of affect recognition program - Indian version.

PubMed

Thonse, Umesh; Behere, Rishikesh V; Frommann, Nicole; Sharma, Psvn

2018-01-01

Social cognition refers to mental operations involved in processing of social cues and includes the domains of emotion processing, Theory of Mind (ToM), social perception, social knowledge and attributional bias. Significant deficits in ToM, emotion perception and social perception have been demonstrated in schizophrenia which can have an impact on socio-occupational functioning. Intervention modules for social cognition have demonstrated moderate effect sizes for improving emotion identification and discrimination. We describe the Indian version of the Training of Affect Recognition (TAR) program and a pilot study to demonstrate the feasibility of administering this intervention program in the Indian population. We also discuss the cultural sensibilities in adopting an intervention program for the Indian setting. To the best of our knowledge this is the first intervention program for social cognition for use in persons with schizophrenia in India. Copyright © 2017 Elsevier B.V. All rights reserved.

Nurse perceptions of workplace environment: differences across shifts.

PubMed

Teclaw, Robert; Osatuke, Katerine

2015-11-01

To evaluate whether nurse work shift affected workplace perceptions. Although the importance of work schedule in shaping work attitudes, generally (and specifically for nurses) is well accepted, much work remains in characterising how and why nurses' perceptions might differ across shifts. Using an exploratory study of observational data, we examined whether shift influenced non-supervisory nurses' job perceptions in the Veterans Health Administration All Employee Survey (n = 14057; years 2008, 2010, 2012). The size of differences in item means (95% C.I.) across shifts was evaluated graphically. Using ordinal logistic regression, we accounted for the ordinal outcome variables and controlled for the demographic and survey year effects. Nurses' perceptions of workplace climate differed across shifts. Items with the greatest differences, consistent across years and analytic methods, involved supervisors and fairness. Night and weekend shift nurse ratings were more negative than for weekday shift nurses. Off-shift nurses are less satisfied with work/life balance, their supervisors and especially fairness. Overall satisfaction and turnover intention are not affected to the same extent. These results indicate several specific areas that nurse managers can address through workforce support and communication. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Influence of visual path information on human heading perception during rotation.

PubMed

Li, Li; Chen, Jing; Peng, Xiaozhe

2009-03-31

How does visual path information influence people's perception of their instantaneous direction of self-motion (heading)? We have previously shown that humans can perceive heading without direct access to visual path information. Here we vary two key parameters for estimating heading from optic flow, the field of view (FOV) and the depth range of environmental points, to investigate the conditions under which visual path information influences human heading perception. The display simulated an observer traveling on a circular path. Observers used a joystick to rotate their line of sight until deemed aligned with true heading. Four FOV sizes (110 x 94 degrees, 48 x 41 degrees, 16 x 14 degrees, 8 x 7 degrees) and depth ranges (6-50 m, 6-25 m, 6-12.5 m, 6-9 m) were tested. Consistent with our computational modeling results, heading bias increased with the reduction of FOV or depth range when the display provided a sequence of velocity fields but no direct path information. When the display provided path information, heading bias was not influenced as much by the reduction of FOV or depth range. We conclude that human heading and path perception involve separate visual processes. Path helps heading perception when the display does not contain enough optic-flow information for heading estimation during rotation.

Effect of thumb anaesthesia on weight perception, muscle activity and the stretch reflex in man.

PubMed Central

Marsden, C D; Rothwell, J C; Traub, M M

1979-01-01

1. We have confirmed the results of Gandevia & McCloskey (1977) on the effect of thumb anaesthesia on perception of weights lifted by the thumb. Weights lifted by flexion feel heavier and weights lifted by extension feel lighter. 2. The change in size of the long-latency stretch reflex in flexor pollicis longus or extensor pollicis longus after thumb anaesthesia cannot explain the effect on weight perception by removal or augmentation of the background servo assistance to muscular contraction. 3. During smooth thumb flexion, thumb anaesthesia increases e.m.g. activity in flexor pollicis longus and extensor pollicis longus for any given opposing torque. 4. During smooth thumb extension the opposite occurs: e.m.g. activity in both extensor and flexor pollicis longus decreases. 5. Clamping the thumb at the proximal phalanx to limit movement solely to the interphalangeal joint reduces or abolishes the effect of anaesthesia on both weight perception and e.m.g. activity during both flexion or extension tasks. 6. Gandevia & McCloskey's findings on the distorting effects of thumb anaesthesia on weight perception cannot be used to support the hypothesis of an efferent monitoring system of the sense of effort. Our results emphasize the close functional relationship between cutaneous and joint afferent information and motor control. PMID:512948

The role of body image and self-perception in anorexia nervosa: the neuroimaging perspective.

PubMed

Esposito, Roberto; Cieri, Filippo; di Giannantonio, Massimo; Tartaro, Armando

2018-03-01

Anorexia nervosa is a severe psychiatric illness characterized by intense fear of gaining weight, relentless pursuit of thinness, deep concerns about food and a pervasive disturbance of body image. Functional magnetic resonance imaging tries to shed light on the neurobiological underpinnings of anorexia nervosa. This review aims to evaluate the empirical neuroimaging literature about self-perception in anorexia nervosa. This narrative review summarizes a number of task-based and resting-state functional magnetic resonance imaging studies in anorexia nervosa about body image and self-perception. The articles listed in references were searched using electronic databases (PubMed and Google Scholar) from 1990 to February 2016 using specific key words. All studies were reviewed with regard to their quality and eligibility for the review. Differences in brain activity were observed using body image perception and body size estimation tasks showing significant modifications in activity of specific brain areas (extrastriate body area, fusiform body area, inferior parietal lobule). Recent studies highlighted the role of emotions and self-perception in anorexia nervosa and their neural substrate involving resting-state networks and particularly frontal and posterior midline cortical structures within default mode network and insula. These findings open new horizons to understand the neural substrate of anorexia nervosa. © 2016 The British Psychological Society.

Demonstration of an ebbinghaus illusion at a memory level: manipulation of the memory size and not the perceptual size.

PubMed

Rey, Amandine Eve; Riou, Benoit; Versace, Rémy

2014-01-01

Based on recent behavioral and neuroimaging data suggesting that memory and perception are partially based on the same sensorimotor system, the theoretical aim of the present study was to show that it is difficult to dissociate memory mechanisms from perceptual mechanisms other than on the basis of the presence (perceptual processing) or absence (memory processing) of the characteristics of the objects involved in the processing. In line with this assumption, two experiments using an adaptation of the Ebbinghaus illusion paradigm revealed similar effects irrespective of whether the size difference between the inner circles and the surrounding circles was manipulated perceptually (the size difference was perceptually present, Experiment 1) or merely reactivated in memory (the difference was perceptually absent, Experiment 2).

Association between weight perception and socioeconomic status among adults in the Seychelles.

PubMed

Alwan, Heba; Viswanathan, Bharathi; Williams, Julita; Paccaud, Fred; Bovet, Pascal

2010-08-09

Few studies have examined the association between weight perception and socioeconomic status (SES) in sub-Saharan Africa, and none made this association based on education, occupation and income simultaneously. Based on a population-based survey (n = 1255) in the Seychelles, weight and height were measured and self-perception of one's own body weight, education, occupation, and income were assessed by a questionnaire. Individuals were considered to have appropriate weight perception when their self-perceived weight matched their actual body weight. The prevalence of overweight and obesity was 35% and 28%, respectively. Multivariate analysis among overweight/obese persons showed that appropriate weight perception was directly associated with actual weight, education, occupation and income, and that it was more frequent among women than among men. In a model using all three SES indicators together, only education (OR = 2.5; 95% CI: 1.3-4.8) and occupation (OR = 2.3; 95% CI: 1.2-4.5) were independently associated with appropriate perception of being overweight. The OR reached 6.9 [95% CI: 3.4-14.1] when comparing the highest vs. lowest categories of SES based on a score including all SES indicators and 6.1 [95% CI: 3.0-12.1] for a score based on education and occupation. Appropriately perceiving one's weight as too high was associated with different SES indicators, female sex and being actually overweight. These findings suggest means and targets for clinical and population-based interventions for weight control. Further studies should examine whether these differences in weight perception underlie differences in cognitive skills, healthy weight norms, or body size ideals.

Shared University Governance: Faculty Perceptions on Involvement and Leadership

ERIC Educational Resources Information Center

Johnson, Adrianne L.; DuVivier, Roxanne S.; Hambright, W. Grant

2017-01-01

This article examines motivations for faculty involvement in shared governance. Faculty members at a mid-sized, Midwestern university were surveyed to assess reasons for serving and leading in the shared governance process. Five predominant themes were identified as affecting faculty participation in university governance. The five predominant…

Working with Large Class Size: Dispositions of Early Childhood Teachers in India

ERIC Educational Resources Information Center

Gupta, Amita

2004-01-01

Using sociocultural-historical constructivism, and post-colonial theory, the author conducted a study to examine, through the perceptions of teachers, school principals, and teacher educators, the relationship between the preparation and practice of early childhood teachers in private schools in New Delhi, India. The research questions…

International Students' Views on Local Culture: Turkish Experience

ERIC Educational Resources Information Center

Çetin, Yakup; Bahar, Mustafa; Griffiths, Carol

2017-01-01

The number of international students in Turkey has steadily increased in recent years. As they come from different geographical locations, their successful adaptation to a medium sized country in-between three continents is of great interest. This study was conducted to investigate international students' perceptions of their Turkish experience.…

The Career Choice of Business Graduates: SMEs or MNCs?

ERIC Educational Resources Information Center

Moy, Jane W.; Lee, Sze M.

2002-01-01

Business undergraduates' (n=116) ratings of job attributes were overall less favorable for small/medium-sized enterprises (SMEs) than multinational corporations. SME employers' (n=30) perceptions of the attractiveness of these attributes were very different. Comparison of recruitment packages indicated that job security and long-term career…

Prosody Production and Perception with Conversational Speech

ERIC Educational Resources Information Center

Mo, Yoonsook

2010-01-01

Speech utterances are more than the linear concatenation of individual phonemes or words. They are organized by prosodic structures comprising phonological units of different sizes (e.g., syllable, foot, word, and phrase) and the prominence relations among them. As the linguistic structure of spoken languages, prosody serves an important function…

Supersizing: Portion Confusion among College Students

ERIC Educational Resources Information Center

Sealey-Potts, Claudia; Alfaro, Veronica; Horine, Suzanne; Kallus, Kelli

2009-01-01

The phrase "bigger is better" has become a common theme among Americans. The purpose of this study was to assess college students' portions and perception of recommended serving sizes of specific foods and beverages and to describe relationships of outcomes with body mass index and demographic variables. The findings indicated that…

One Size Does Not Fit All: Managing Radical and Incremental Creativity

ERIC Educational Resources Information Center

Gilson, Lucy L.; Lim, Hyoun Sook; D'Innocenzo, Lauren; Moye, Neta

2012-01-01

This research extends creativity theory by re-conceptualizing creativity as a two-dimensional construct (radical and incremental) and examining the differential effects of intrinsic motivation, extrinsic rewards, and supportive supervision on perceptions of creativity. We hypothesize and find two distinct types of creativity that are associated…

Too Many Friends: Social Integration, Network Cohesion and Adolescent Depressive Symptoms

ERIC Educational Resources Information Center

Falci, Christina; McNeely, Clea

2009-01-01

Using a nationally representative sample of adolescents, we examine associations among social integration (network size), network cohesion (alter-density), perceptions of social relationships (e.g., social support) and adolescent depressive symptoms. We find that adolescents with either too large or too small a network have higher levels of…

Women and the Superintendency: Perceptions of Gender Bias

ERIC Educational Resources Information Center

Garn, Gregg; Brown, Casey

2008-01-01

This research explored how 15 female superintendents from a southwestern state experienced issues of gender bias. Participants came from a mix of urban, rural, and suburban districts that varied in size from 150 to 25,000 students. Using in-depth interviews and a transcendental phenomenological qualitative approach, the researchers examined how…

Development of Professional Identity in SMEs.

ERIC Educational Resources Information Center

Puurula, Arja; Lofstrom, Erika

This paper describes a study of the development of professional identity among employees in small and medium sized enterprises (SMEs) participating in large-scale company-wide training programs. Managers and employees in 175 SMEs in Finland participated. These two research questions were posed: (1) are there differences in the perceptions of…

Do Teachers Perceive Co-Teaching as an Effective Instructional Model?

ERIC Educational Resources Information Center

Roberson, Gregory L.

2014-01-01

This qualitative action research study examined teachers' perceptions about co-teaching and its effectiveness as an instructional model for students with disabilities. One-on-one interviews were conducted with eight elementary and secondary teachers from a medium sized school district located in Southwest Ohio that has a students' with…

Students' and Professors' Views on the Ethics of Faculty Behavior.

ERIC Educational Resources Information Center

Morgan, Betsy Levonian; And Others

This study compared students' and professors' perceptions of the ethicalness of faculty behavior. A total of 115 professors and 157 undergraduate students at a medium-sized public Midwestern university completed a 16-item faculty behavior scale adapted from Tabachnick and colleagues (1991) work. Significant differences between student and faculty…

Perceptions of Library Leadership in a Time of Change.

ERIC Educational Resources Information Center

Deekle, Peter V.; de Klerk, Ann

1992-01-01

Reports on a survey of chief academic officers and library directors at over 250 small- and medium-sized private colleges and universities. Responses indicate that institution administrators were aware of new trends in information management but did not recognize library directors' qualifications for broader administrative participation. (11…

A Bully-Free School

ERIC Educational Resources Information Center

Neville, Christine S.

2012-01-01

Bullies come in all sizes, shapes, ages, genders, and ethnicities. Bullies generally attack that which they do not understand, what is strange, different from their perception of the norm or someone whom they resent. Their motivation has to do with making themselves feel stronger, more secure or to compensate for their own sad experiences.…

Principals' Participation Levels in Best Practices for School Improvement

ERIC Educational Resources Information Center

Stogdill, Christopher T.

2010-01-01

The purpose of this study was to identify Nebraska principal perceptions regarding the level of participation the AdvancED school improvement process. Further, the study identified differences among principals' knowledge, based on demographic characteristics of years of experience, size of school enrollments, and formal training in school…

Benefits of a Graduate Business Degree: Students' Perspectives and Universities' Challenges.

ERIC Educational Resources Information Center

Webb, Marion Stanton; Allen, Lida Cherie

1995-01-01

A survey of 1,499 graduate business students at 7 colleges and universities investigated perceptions of potential benefits of an advanced degree, and their relationships with degree type, school size/type, and student characteristics. Five perceived benefits included research and analytical skills, competitive advantage, monetary reward, career…

Experimental orofacial pain and sensory deprivation lead to perceptual distortion of the face in healthy volunteers.

PubMed

Dagsdóttir, Lilja Kristín; Skyt, Ina; Vase, Lene; Baad-Hansen, Lene; Castrillon, Eduardo; Svensson, Peter

2015-09-01

Patients suffering from persistent orofacial pain may sporadically report that the painful area feels "swollen" or "differently," a phenomenon that may be conceptualized as a perceptual distortion because there are no clinical signs of swelling present. Our aim was to investigate whether standardized experimental pain and sensory deprivation of specific orofacial test sites would lead to changes in the size perception of these face areas. Twenty-four healthy participants received either 0.2 mL hypertonic saline (HS) or local anesthetics (LA) into six regions (buccal, mental, lingual, masseter muscle, infraorbital and auriculotemporal nerve regions). Participants estimated the perceived size changes in percentage (0 % = no change, -100 % = half the size or +100 % = double the size), and somatosensory function was checked with tactile stimuli. The pain intensity was rated on a 0-10 Verbal Numerical Rating Scale (VNRS), and sets of psychological questionnaires were completed. HS and LA were associated with significant self-reported perceptual distortions as indicated by consistent increases in perceived size of the adjacent face areas (P ≤ 0.050). Perceptual distortion was most pronounced in the buccal region, and the smallest increase was observed in the auriculotemporal region. HS was associated with moderate levels of pain VNRS = 7.3 ± 0.6. Weak correlations were found between HS-evoked perceptual distortion and level of dissociation in two regions (P < 0.050). Experimental pain and transient sensory deprivation evoked perceptual distortions in all face regions and overall demonstrated the importance of afferent inputs for the perception of the face. We propose that perceptual distortion may be an important phenomenon to consider in persistent orofacial pain conditions.

3-Dimensional Scene Perception during Active Electrolocation in a Weakly Electric Pulse Fish

PubMed Central

von der Emde, Gerhard; Behr, Katharina; Bouton, Béatrice; Engelmann, Jacob; Fetz, Steffen; Folde, Caroline

2010-01-01

Weakly electric fish use active electrolocation for object detection and orientation in their environment even in complete darkness. The African mormyrid Gnathonemus petersii can detect object parameters, such as material, size, shape, and distance. Here, we tested whether individuals of this species can learn to identify 3-dimensional objects independently of the training conditions and independently of the object's position in space (rotation-invariance; size-constancy). Individual G. petersii were trained in a two-alternative forced-choice procedure to electrically discriminate between a 3-dimensional object (S+) and several alternative objects (S−). Fish were then tested whether they could identify the S+ among novel objects and whether single components of S+ were sufficient for recognition. Size-constancy was investigated by presenting the S+ together with a larger version at different distances. Rotation-invariance was tested by rotating S+ and/or S− in 3D. Our results show that electrolocating G. petersii could (1) recognize an object independently of the S− used during training. When only single components of a complex S+ were offered, recognition of S+ was more or less affected depending on which part was used. (2) Object-size was detected independently of object distance, i.e. fish showed size-constancy. (3) The majority of the fishes tested recognized their S+ even if it was rotated in space, i.e. these fishes showed rotation-invariance. (4) Object recognition was restricted to the near field around the fish and failed when objects were moved more than about 4 cm away from the animals. Our results indicate that even in complete darkness our G. petersii were capable of complex 3-dimensional scene perception using active electrolocation. PMID:20577635

How Weight Affects the Perceived Spacing between the Thumb and Fingers during Grasping

PubMed Central

Butler, Annie A.; Héroux, Martin E.; Gandevia, Simon C.

2015-01-01

We know much about mechanisms determining the perceived size and weight of lifted objects, but little about how these properties of size and weight affect the body representation (e.g. grasp aperture of the hand). Without vision, subjects (n = 16) estimated spacing between fingers and thumb (perceived grasp aperture) while lifting canisters of the same width (6.6cm) but varied weights (300, 600, 900, and 1200 g). Lifts were performed by movement of either the wrist, elbow or shoulder to examine whether lifting with different muscle groups affects the judgement of grasp aperture. Results for perceived grasp aperture were compared with changes in perceived weight of objects of different sizes (5.2, 6.6, and 10 cm) but the same weight (600 g). When canisters of the same width but different weights were lifted, perceived grasp aperture decreased 4.8% [2.2 ‒ 7.4] (mean [95% CI]; P < 0.001) from the lightest to the heaviest canister, no matter how they were lifted. For objects of the same weight but different widths, perceived weight decreased 42.3% [38.2 ‒ 46.4] from narrowest to widest (P < 0.001), as expected from the size-weight illusion. Thus, despite a highly distorted perception of the weight of objects based on their size, we conclude that proprioceptive afferents maintain a reasonably stable perception of the aperture of the grasping hand over a wide range of object weights. Given the small magnitude of this ‘weight-grasp aperture’ illusion, we propose the brain has access to a relatively stable ‘perceptual ruler’ to aid the manipulation of different objects. PMID:25996760

Ground-plane influences on size estimation in early visual processing.

PubMed

Champion, Rebecca A; Warren, Paul A

2010-07-21

Ground-planes have an important influence on the perception of 3D space (Gibson, 1950) and it has been shown that the assumption that a ground-plane is present in the scene plays a role in the perception of object distance (Bruno & Cutting, 1988). Here, we investigate whether this influence is exerted at an early stage of processing, to affect the rapid estimation of 3D size. Participants performed a visual search task in which they searched for a target object that was larger or smaller than distracter objects. Objects were presented against a background that contained either a frontoparallel or slanted 3D surface, defined by texture gradient cues. We measured the effect on search performance of target location within the scene (near vs. far) and how this was influenced by scene orientation (which, e.g., might be consistent with a ground or ceiling plane, etc.). In addition, we investigated how scene orientation interacted with texture gradient information (indicating surface slant), to determine how these separate cues to scene layout were combined. We found that the difference in target detection performance between targets at the front and rear of the simulated scene was maximal when the scene was consistent with a ground-plane - consistent with the use of an elevation cue to object distance. In addition, we found a significant increase in the size of this effect when texture gradient information (indicating surface slant) was present, but no interaction between texture gradient and scene orientation information. We conclude that scene orientation plays an important role in the estimation of 3D size at an early stage of processing, and suggest that elevation information is linearly combined with texture gradient information for the rapid estimation of 3D size. Copyright 2010 Elsevier Ltd. All rights reserved.

Effect of field of view and monocular viewing on angular size judgements in an outdoor scene

NASA Technical Reports Server (NTRS)

Denz, E. A.; Palmer, E. A.; Ellis, S. R.

1980-01-01

Observers typically overestimate the angular size of distant objects. Significantly, overestimations are greater in outdoor settings than in aircraft visual-scene simulators. The effect of field of view and monocular and binocular viewing conditions on angular size estimation in an outdoor field was examined. Subjects adjusted the size of a variable triangle to match the angular size of a standard triangle set at three greater distances. Goggles were used to vary the field of view from 11.5 deg to 90 deg for both monocular and binocular viewing. In addition, an unrestricted monocular and binocular viewing condition was used. It is concluded that neither restricted fields of view similar to those present in visual simulators nor the restriction of monocular viewing causes a significant loss in depth perception in outdoor settings. Thus, neither factor should significantly affect the depth realism of visual simulators.

The Effects of Transient Emotional State and Workload on Size Scaling in Perspective Displays

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tuan Q. Tran; Kimberly R. Raddatz

2006-10-01

Previous research has been devoted to the study of perceptual (e.g., number of depth cues) and cognitive (e.g., instructional set) factors that influence veridical size perception in perspective displays. However, considering that perspective displays have utility in high workload environments that often induce high arousal (e.g., aircraft cockpits), the present study sought to examine the effect of observers’ emotional state on the ability to perceive and judge veridical size. Within a dual-task paradigm, observers’ ability to make accurate size judgments was examined under conditions of induced emotional state (positive, negative, neutral) and high and low workload. Results showed that participantsmore » in both positive and negative induced emotional states were slower to make accurate size judgments than those not under induced emotional arousal. Results suggest that emotional state is an important factor that influences visual performance on perspective displays and is worthy of further study.« less

Size Matters: Community Size, HIV Stigma, & Gender Differences

PubMed Central

Gonzalez, Adam; Miller, Carol T.; Solomon, Sondra E.; Bunn, Janice Yanushka; Cassidy, Daniel G.

2012-01-01

Conclusions regarding HIV stigma in rural areas are hampered by lack of agreement about rural classification. This investigation examined perceptions of HIV stigma among males and females with HIV/AIDS in metropolitan, micropolitan, and rural areas. Two-hundred people with HIV/AIDS completed a measure of perceived HIV stigma. Their county or town of residence was used to classify community size. Results indicated that community size was related to one aspect of perceived stigma, disclosure concerns, differently for men and women. Rural women reported more disclosure concerns than did metropolitan and micropolitan women. They also reported more disclosure concerns than rural men. Men in micropolitan communities reported more disclosure concerns than men in rural areas and tended to report more disclosure concerns than men in metropolitan areas. Understanding the relationship of community size to HIV stigmatization requires acknowledging that many communities are neither urban nor rural, and it requires considering gender differences. PMID:18815878

Neural Substrate of Body Size: Illusory Feeling of Shrinking of the Waist

PubMed Central

Kito, Tomonori; Sadato, Norihiro; Passingham, Richard E; Naito, Eiichi

2005-01-01

The perception of the size and shape of one's body (body image) is a fundamental aspect of how we experience ourselves. We studied the neural correlates underlying perceived changes in the relative size of body parts by using a perceptual illusion in which participants felt that their waist was shrinking. We scanned the brains of the participants using functional magnetic resonance imaging. We found that activity in the cortices lining the left postcentral sulcus and the anterior part of the intraparietal sulcus reflected the illusion of waist shrinking, and that this activity was correlated with the reported degree of shrinking. These results suggest that the perceived changes in the size and shape of body parts are mediated by hierarchically higher-order somatosensory areas in the parietal cortex. Based on this finding we suggest that relative size of body parts is computed by the integration of more elementary somatic signals from different body segments. PMID:16336049

Neural network architecture for form and motion perception (Abstract Only)

NASA Astrophysics Data System (ADS)

Grossberg, Stephen

1991-08-01

Evidence is given for a new neural network theory of biological motion perception, a motion boundary contour system. This theory clarifies why parallel streams V1 yields V2 and V1 yields MT exist for static form and motion form processing among the areas V1, V2, and MT of visual cortex. The motion boundary contour system consists of several parallel copies, such that each copy is activated by a different range of receptive field sizes. Each copy is further subdivided into two hierarchically organized subsystems: a motion oriented contrast (MOC) filter, for preprocessing moving images; and a cooperative-competitive feedback (CC) loop, for generating emergent boundary segmentations of the filtered signals. The present work uses the MOC filter to explain a variety of classical and recent data about short-range and long- range apparent motion percepts that have not yet been explained by alternative models. These data include split motion; reverse-contrast gamma motion; delta motion; visual inertia; group motion in response to a reverse-contrast Ternus display at short interstimulus intervals; speed- up of motion velocity as interflash distance increases or flash duration decreases; dependence of the transition from element motion to group motion on stimulus duration and size; various classical dependencies between flash duration, spatial separation, interstimulus interval, and motion threshold known as Korte''s Laws; and dependence of motion strength on stimulus orientation and spatial frequency. These results supplement earlier explanations by the model of apparent motion data that other models have not explained; a recent proposed solution of the global aperture problem including explanations of motion capture and induced motion; an explanation of how parallel cortical systems for static form perception and motion form perception may develop, including a demonstration that these parallel systems are variations on a common cortical design; an explanation of why the geometries of static form and motion form differ, in particular why opposite orientations differ by 90 degree(s), whereas opposite directions differ by 180 degree(s), and why a cortical stream V1 yields V2 yields MT is needed; and a summary of how the main properties of other motion perception models can be assimilated into different parts of the motion boundary contour system design.

Social and Biophysical Predictors of Public Perceptions of Extreme Fires

NASA Astrophysics Data System (ADS)

Hall, T. E.; Kooistra, C. M.; Paveglio, T.; Gress, S.; Smith, A. M.

2013-12-01

To date, what constitutes an 'extreme' fire has been approached separately by biophysical and social scientists. Research on the biophysical characteristics of fires has identified potential dimensions of extremity, including fire size and vegetation mortality. On the social side, factors such as the degree of immediate impact to one's life and property or the extent of social disruption in the community contribute to a perception of extremity. However, some biophysical characteristics may also contribute to perceptions of extremity, including number of simultaneous ignitions, rapidity of fire spread, atypical fire behavior, and intensity of smoke. Perceptions of these impacts can vary within and across communities, but no studies to date have investigated such perceptions in a comprehensive way. In this study, we address the question, to what extent is the magnitude of impact of fires on WUI residents' well-being explained by measurable biophysical characteristics of the fire and subjective evaluations of the personal and community-level impacts of the fire? We bring together diverse strands of psychological theory, including landscape perception, mental models, risk perception, and community studies. The majority of social science research on fires has been in the form of qualitative case studies, and our study is methodologically unique by using a nested design (hierarchical modeling) to enable generalizable conclusions across a wide range of fires and human communities. We identified fires that burned in 2011 or 2012 in the northern Rocky Mountain region that were at least 1,000 acres and that intersected (within 15 km) urban clusters or identified Census places. For fires where an adequately large number of households was located in proximity to the fire, we drew random samples of approximately 150 individuals for each fire. We used a hybrid internet (Qualtrics) and mail survey, following the Dillman method, to measure individual perceptions. We developed two composite dependent variables: (1) subjective perceptions of the atypicality of the fire; and (2) perceptions of the fire's impact to individual and community well-being. The impact measures were adapted from the hazards and disasters literature and used a multi-item measure of emotional response during and immediately after the fire. Independent variables included both biophysical characteristics of each fire (such as size, duration, and burn severity), obtained from remotely sensed imagery, and perceptual variables measured in the survey. All measures were pilot tested for adequate psychometric properties using a sample of 150 individuals from an on-line panel who had been affected by a wildfire within the past two years. Factor analysis techniques will be used to reduce the data to latent constructs for use in regression modeling. Hierarchical linear modeling will be used to identify factors predicting the impact of fires on individuals (level 1) and whether those factors differ by fire (level 2). Our study provides a unique interdisciplinary perspective on extreme disturbance events, and findings will help land managers and community leaders anticipate how individuals may respond to future fires, as well as how to ameliorate the negative impacts of those fires.

Dancer perceptions of the force reduction of dance floors used by a professional touring ballet company.

PubMed

Hopper, Luke S; Wheeler, Talia J; Webster, James M; Allen, Nick; Roberts, Jonathan R; Fleming, Paul R

2014-01-01

The mechanical properties of dance floors have the potential to influence dancers' performance and injury risk. Little information is available that describes dancers' preferences for dance floor mechanical properties. Investigation of dancers' perceptions of varied dance floors can serve to enlighten governing bodies, floor manufacturers, and the dance community. The aim of this study was to assess the perceptions of dancers from a touring professional ballet company regarding four floors with varied force reduction (FR) that were created to replicate those used by the company in normal dance training and performance. A specialized questionnaire was developed that incorporated a series of qualitative and quantitative measures that could be used by participants to express their perceptions of the custom built dance floors. Floor FR was quantified with reference to the protocols specified by European standards. Dancer perceptions were in general agreement with floor FR values; however, some discrepancies were observed. Dancers expressed a preference for floor FR within the mid to upper limits (57% to 72%) of the European standards, although a minority preferred low FR (approximately 36%) floors. A limited ability to perceive inconsistencies in FR across test floors was observed, which may have implications for injury risk. Investigation of the perceptions of dancers from more diverse backgrounds, on floors that provide a closer representation of typical dance studio and stage sizes, over longer periods of time, would provide further insight into the perceptual and adaptive responses of dancers to varied floor mechanical properties.

The effect of a portion size intervention on French fries consumption, plate waste, satiety and compensatory caloric intake: an on-campus restaurant experiment.

PubMed

Vermote, Marie; Versele, Vickà; Stok, Marijn; Mullie, Patrick; D'Hondt, Eva; Deforche, Benedicte; Clarys, Peter; Deliens, Tom

2018-04-13

One of the driving factors of dietary overconsumption throughout the last decennia is the increase of food portion sizes. Larger portions induce higher daily energy intake, so reducing portion size may reduce intake of excess calories. However, real-life studies about the effects of portion size reduction are lacking. Therefore, this study examined the effect of a French fries portion size reduction on French fries consumption, French fries plate waste, satiety and caloric intake during the subsequent afternoon among university students and employees in a Belgian on-campus restaurant setting. Moreover, this study evaluated consumers' perception about the portion size reduction. The study took place over a two-time (i.e. baseline and intervention week) 4-day period (Tuesday-Friday) in the on-campus restaurant where ±1200 meals are served every day. French fries' portions were reduced by 20% by replacing the usual porcelain bowl served during the baseline week (±200 g) with smaller volume paper bags during the intervention week (±159 g) in a pre-post real-life experiment. French fries consumption and plate waste were measured in 2056 consumers at baseline and 2175 consumers at intervention. Additionally, interviews were conducted directly after lunch and again between 4 and 6 p.m. on the same day to assess satiety and caloric intake at pre and post in a small subsample of both French fries consumers (n = 19) and non-French fries consumers (n = 14). Post-intervention, the same subsample was interviewed about their perception of the portion size reduction (n = 28). Total French fries intake decreased by 9.1%, and total plate waste decreased by 66.4%. No differences were found in satiety or caloric intake between baseline and intervention week among the French fries' consumers. The majority (n = 24, 86%) of French fries consumers noticed the reduction in portion size during the intervention. Although most participants (n = 19, 68%) perceived the reduced portion size as sufficient, only a minority of participants (n = 9, 32%) indicated post-intervention that they would agree with a permanent implementation. Reducing portion size may lead to reduced caloric intake, without changing perceived levels of satiety.

Explaining body size beliefs in anorexia.

PubMed

Gadsby, Stephen

2017-11-01

Cognitive neuropsychiatry has had much success in providing theoretical models for the causal origins of many delusional beliefs. Recently, it has been suggested that some anorexia nervosa patients' beliefs about their own body size should be considered delusions. As such, it seems high time the methods of cognitive neuropsychiatry were turned to modelling the false body size beliefs of anorexics. In this paper, I adopt an empiricist approach to modelling the causal origins of false body size beliefs in anorexia. Within the background of cognitive neuropsychiatry, empiricist models claim that abnormal beliefs are grounded by abnormal experiences bearing similar content. I discuss the kinds of abnormal experiences of body size anorexics suffer from which could ground their false beliefs about body size. These oversized experiences come in three varieties: false self-other body comparisons, spontaneous mental imagery of a fat body and distorted perception of affordances. Further theoretical and empirical research into the oversized experiences which anorexics suffer from presents a promising avenue for understanding and treating the disorder.

Perceptıon scale of barrıers to contraceptıve use: a methodologıcal study.

PubMed

Sen, Selma; Cetinkaya, Aynur; Cavuslar, Aysel

2017-01-01

The objective of this study was to design and develop the Perception Scale of Barriers to Contraceptive Use (PSBCU) as a measurement tool for the qualitative assessment of the barriers and obstacles women perceived with regard to contraceptive use or low rates of contraceptive use in women using family planning services. The data for this methodological study were collected using the face-to-face interview technique from 320 married women between the ages of 15-49 who were attending clinics at the Hafsa Sultan Hospital, CBU. The data collection tools used in the study, which was carried out from May to September 2014, were the "Introductory Information Form" and the "Perception Scale of Barriers to Contraceptive Use". Language validity and construct validity (explanatory factor analysis) were applied in order to test the validity of the Perception Scale of Barriers to Contraceptive Use. Kaiser Meier Olkin (KMO) analysis was performed to determine the availability of the scale for the size of participants. The sample adequacy calculated as the KMO value was 0.916 and the Bartlett's Test of Sphericity (X 2  = 6721.793 p  < 0.000) sample size analysis value was found to be sufficient for factor analysis. The total Cronbach's Alpha coefficient of 34 items which included three factors explaining 54.95% of the variance after Varimax rotation was calculated to be 0.95. The largest factor was the "cognitive domain" explaining 18.89% of the variance, followed by the "emotional domain" explaining 18.05% of the variance, and finally the "social domain" explaining 18.01% of the variance. Item-total score correlation coefficients of scale items were found to be between 0.54 and 0.83. The study demonstrateded that the "Perception Scale of Barriers to Contraceptive Use" was valid and reliable. We believe that the scale is suitable for use by women in a family planning education and training programs in order to evaluate their situation. It should also be assessed for validity and reliability for different groups (adolescents, men, etc.).

Asteroid (4179) Toutatis size determination via optical images observed by the Chang'e-2 probe

NASA Astrophysics Data System (ADS)

Liu, P.; Huang, J.; Zhao, W.; Wang, X.; Meng, L.; Tang, X.

2014-07-01

This work is a physical and statistical study of the asteroid (4179) Toutatis using the optical images obtained by a solar panel monitor of the Chang'e-2 probe on Dec. 13, 2012 [1]. In the imaging strategy, the camera is focused at infinity. This is specially designed for the probe with its solar panels monitor's principle axis pointing to the relative velocity direction of the probe and Toutatis. The imaging strategy provides a dedicated way to resolve the size by multi-frame optical images. The inherent features of the data are: (1) almost no rotation was recorded because of the 5.41-7.35 Earth-day rotation period and the small amount of elapsed imaging time, only minutes, make the object stay in the images in a fixed position and orientation; (2) the sharpness of the upper left boundary and the vagueness of lower right boundary resulting from the direction of SAP (Sun-Asteroid-Probe angle) cause a varying accuracy in locating points at different parts of Toutatis. A common view is that direct, accurate measurements of asteroid shapes, sizes, and pole positions are now possible for larger asteroids that can be spatially resolved using the Hubble Space Telescope or large ground-based telescopes equipped with adaptive optics. For a quite complex planetary/asteroid probe study, these measurements certainly need continuous validation via a variety of ways [2]. Based on engineering parameters of the probe during the fly-by, the target spatial resolving and measuring procedures are described in the paper. Results estimated are optical perceptible size on the flyby epoch under the solar phase angles during the imaging. It is found that the perceptible size measured using the optical observations and the size derived from the radar observations by Ostro et al.~in 1995 [3], are close to one another.

The Role of Student-Teacher Ratio in Parents' Perceptions of Schools' Engagement Efforts

ERIC Educational Resources Information Center

Rodriguez, Raymond J.; Elbaum, Batya

2014-01-01

Research suggests a positive relationship between schools' efforts to engage parents and parents' involvement in their child's education. The authors investigated school socioeconomic status, school size, grade level, and student-teacher ratio as predictors of schools' efforts to engage parents of students receiving special education services. The…

Adolescent Obesity Prevention in Botswana: Beliefs and Recommendations of School Personnel

ERIC Educational Resources Information Center

Shaibu, Sheila; Holsten, Joanna E.; Stettler, Nicolas; Maruapula, Segametsi D.; Jackson, Jose C.; Malete, Leapetswe; Mokone, George; Wrotniak, Brian H.; Compher, Charlene W.

2012-01-01

The study's objectives were to gain school personnel's (1) perceptions on diet, physical activity, body size, and obesity, (2) description of school food and physical activity practices, and (3) recommendations for programs to prevent adolescent obesity. The study took place in six junior secondary schools of varying socioeconomic status in…

Increasing Social Presence in Online Learning through Small Group Discussions

ERIC Educational Resources Information Center

Akcaoglu, Mete; Lee, Eunbae

2016-01-01

Social presence is difficult to achieve, but an imperative component of online learning. In this study, we investigated the effect of group size on students' perceptions of social presence in two graduate-level online courses, comparing small group versus whole class discussions. Our results indicated that when in small group discussions, students…

Factors Affecting Applicants' Acceptance or Decline of Offers to Enroll in a Medical School.

ERIC Educational Resources Information Center

Cleave-Hogg, Doreen; And Others

1994-01-01

A University of Toronto (Canada) study of medical school applicants accepting (n=784) and declining (n=255) admission identified influential factors. Some (living cost, location) cannot be affected by the institution. The institution has limited control of others (faculty size, school environment) but can influence applicant perceptions. One…

Campus Safety: A Survey of Administrative Perceptions and Strategies.

ERIC Educational Resources Information Center

Beeler, Karl J.; And Others

This paper reports the findings of a 1990 nationwide survey of chief student affairs administrators addressing college and university campus safety issues. Respondents (N=701 out of a total of 1,091 recipients) completed a 24 item questionnaire, and the results were analyzed using frequencies and cross-tabulations for comparisons by size of…

College Professors' Perceptions of and Responses to Relational Aggression in College Students

ERIC Educational Resources Information Center

Fifield, Andrea Owens

2010-01-01

The purpose of this study was to investigate the impact of selected factors on professors' responses to relational aggression in college students. Specifically, this study explored the relationships between professors' gender, class size, level of empathy, ratings of seriousness of a relationally aggressive scenario, the gender of the perpetrator…

Controlling Attention through Action: Observing Actions Primes Action-Related Stimulus Dimensions

ERIC Educational Resources Information Center

Fagioli, Sabrina; Ferlazzo, Fabio; Hommel, Bernhard

2007-01-01

Previous findings suggest that planning an action "backward-primes" perceptual dimension related to this action: planning a grasp facilitates the processing of visual size information, while planning a reach facilitates the processing of location information. Here we show that dimensional priming of perception through action occurs even in the…

An Exploratory Study on International Students' Study Anxiety

ERIC Educational Resources Information Center

Khoshlessan, Rezvan; El-Houbi, Ashraf

2015-01-01

This study examines international students' study anxiety in a mid-sized university in Southeast Texas comparing their existing study anxiety along lines of nationality, gender, age, major, degree, and stage of education. It focuses on the students' perceptions and the dominant goal of this research was to investigate whether there is a…

Transitional Leadership: Perceptions of Interim Mid-Level Student Affairs Professionals

ERIC Educational Resources Information Center

Boerner, William A.

2011-01-01

It has been estimated that, due to increased turnover, an aging population, growing complexities and sizes of institutions, as well as the bureaucratization of searches, college and universities will see a continued increase in the utilization of interim leadership (Padilla, 2004). Student affairs divisions are not immune to this phenomenon and…

Some Factors Relevant to Group Activities in Language Teaching

ERIC Educational Resources Information Center

Mugglestone, Patricia

1975-01-01

Discusses the handling of groups. The teacher should be aware of variables: size of group, composition (by ability, needs, etc.), seating arrangement, group structure, etc. Cooperative, competitive or individual work should be used, depending on the learning goal. The teacher must be perceptive, flexible, and must have good organizing ability.…

Area requirements and landscape-level factors influencing shrubland birds

Treesearch

H. Patrick Roberts; David I. King

2017-01-01

Declines in populations of birds that breed in disturbance-dependent early-successional forest have largely been ascribed to habitat loss. Clearcutting is an efficient and effective means for creating earlysuccessional vegetation; however, negative public perceptions of clearcutting and the small parcel size typical of private forested land in much of the eastern...

Entrepreneurial Skills in Leadership and Human Resource Management Evaluated by Apprentices in Small Tourism Businesses

ERIC Educational Resources Information Center

Peters, Mike

2005-01-01

Purpose: The purpose of this article is to evaluate the leadership skills and entrepreneur's or owner/manager's ability to motivate apprentices and other young employees. Specifically, the article investigates young employees' perceptions about leadership and motivational behaviour in small- and medium-sized hotels. Design/Methodology/Approach:…

The Influence of Prior Knowledge on Perception and Action: Relationships to Autistic Traits

ERIC Educational Resources Information Center

Buckingham, Gavin; Michelakakis, Elizabeth Evgenia; Rajendran, Gnanathusharan

2016-01-01

Autism is characterised by a range of perceptual and sensorimotor deficits, which might be related to abnormalities in how autistic individuals use prior knowledge. We investigated this proposition in a large non-clinical population in the context of the size-weight illusion, where individual's expectations about object weight influence their…

Enhancing SMTEs' Business Performance through the Internet and E-Learning Platforms

ERIC Educational Resources Information Center

Collins, Catherine; Buhalis, Dimitrios; Peters, Mike

2003-01-01

Investigates small and medium-sized tourist enterprises (SMTEs) in the European hotel sector and their utilisation of the Internet and their perception of online learning systems. Aims to demonstrate to SMTEs that training is imperative and that information and communication technologies (ICTs) can enable them to improve their inventory…

The Value of Oral Feedback in the Context of Capstone Projects in Design Education

ERIC Educational Resources Information Center

Karlsen, Kristine Hoeg

2017-01-01

Research frequently reports student dissatisfaction with feedback in higher education. Large class sizes and modularization challenge teachers in providing useful feedback. Most of these studies have investigated student perceptions of written feedback in coursework, and few attempts have been made considering feedback in face-to-face contexts…

Collegiality Matters: Massachusetts Public Higher Education Librarians' Perspective

ERIC Educational Resources Information Center

Freedman, Shin

2012-01-01

It is no secret that collegiality matters in academe regardless of the size and type of institution. When it comes to promotion, reappointment and tenure, the invocation of collegiality occurs. This paper aims to examine the perception and issues surrounding collegiality in the academic library setting. The data, based on the survey results of the…

An Investigation of District Leaders' Perceptions of Forces That Complicate Efforts to Succeed

ERIC Educational Resources Information Center

Petersen, George J.; Kelly, Victoria L.; Reimer, Catherine N.; Mosunich, Daniel; Thompson, Debra

2009-01-01

This study explored the perspectives of 350 California superintendents from various-sized school districts in relation to their ability to support student learning while addressing the numerous and complex personnel, social, and economic challenges faced by schools. Specifically, this study investigated the attitudes and opinions of district…

Perceptions of University Assessment and Feedback among Post-16 School Pupils

ERIC Educational Resources Information Center

Jones, Harriet; Yeoman, Kay; Gaskell, Emma; Prendergast, John

2017-01-01

The transition between school and university can be problematic for students. Understanding students' expectations about the system they are entering is crucial in effecting a smooth transition. The school system involves small classes, often with teachers who know their students well. In contrast, university involves large class sizes and a…

77 FR 59221 - Information Collection Activities: Timpanogos Cave National Monument Visitor and Community Survey

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-26

... of how each of the above management issue affects their overall quality of visit experience. Visitors... collect visitors and local community members' perceptions and evaluations of four management issues (1... management issues: (1) Cave tour size and frequency. (2) Ticketing process and fees. (3) Concession service...

Body Image Satisfaction among Blacks

ERIC Educational Resources Information Center

Gustat, Jeanette; Carton, Thomas W.; Shahien, Amir A.; Andersen, Lori

2017-01-01

Satisfaction with body image is a factor related to health outcomes. The purpose of this study is to examine the relationship between body image satisfaction and body size perception in an urban, Black community sample in New Orleans, Louisiana. Only 42.2% of respondents were satisfied with their body image and 44.1% correctly perceived their body…

Twenty-First Century Literacy: A Matter of Scale from Micro to Mega

ERIC Educational Resources Information Center

Brown, Abbie; Slagter van Tryon, Patricia J.

2010-01-01

Twenty-first century technologies require educators to look for new ways to teach literacy skills. Current communication methods are combinations of traditional and newer, network-driven forms. This article describes the changes twenty-first century technologies cause in the perception of time, size, distance, audience, and available data, and…

Acoustic-tactile rendering of visual information

NASA Astrophysics Data System (ADS)

Silva, Pubudu Madhawa; Pappas, Thrasyvoulos N.; Atkins, Joshua; West, James E.; Hartmann, William M.

2012-03-01

In previous work, we have proposed a dynamic, interactive system for conveying visual information via hearing and touch. The system is implemented with a touch screen that allows the user to interrogate a two-dimensional (2-D) object layout by active finger scanning while listening to spatialized auditory feedback. Sound is used as the primary source of information for object localization and identification, while touch is used both for pointing and for kinesthetic feedback. Our previous work considered shape and size perception of simple objects via hearing and touch. The focus of this paper is on the perception of a 2-D layout of simple objects with identical size and shape. We consider the selection and rendition of sounds for object identification and localization. We rely on the head-related transfer function for rendering sound directionality, and consider variations of sound intensity and tempo as two alternative approaches for rendering proximity. Subjective experiments with visually-blocked subjects are used to evaluate the effectiveness of the proposed approaches. Our results indicate that intensity outperforms tempo as a proximity cue, and that the overall system for conveying a 2-D layout is quite promising.

A new mode of fear expression: perceptual bias in height fear.

PubMed

Teachman, Bethany A; Stefanucci, Jeanine K; Clerkin, Elise M; Cody, Meghan W; Proffitt, Dennis R

2008-04-01

Emotion and psychopathology researchers have described the fear response as consisting of four main components--subjective affect, physiology, cognition, and behavior. The current study provides evidence for an additional component in the domain of height fear (perception) and shows that it is distinct from measures of cognitive processing. Individuals High (N = 35) and Low (N = 36) in acrophobic symptoms looked over a two-story balcony ledge and estimated its vertical extent using a direct height estimation task (visual matching), and an indirect task (size estimation); the latter task seems to exhibit little influence from cognitive factors. In addition, implicit and explicit measures of cognitive processing were obtained. Results indicated that, as expected, the High Fear group showed greater relative, implicit height fear associations and explicit threat cognitions. Of primary interest, the High (compared to Low) Fear group estimated the vertical extent to be higher, and judged target sizes to be greater, even when controlling for the cognitive bias measures. These results suggest that emotional factors such as fear are related to perception. (Copyright) 2008 APA.

Reframing the action and perception dissociation in DF: haptics matters, but how?

PubMed

Whitwell, Robert L; Buckingham, Gavin

2013-02-01

Goodale and Milner's (1992) "vision-for-action" and "vision-for-perception" account of the division of labor between the dorsal and ventral "streams" has come to dominate contemporary views of the functional roles of these two pathways. Nevertheless, some lines of evidence for the model remain controversial. Recently, Thomas Schenk reexamined visual form agnosic patient DF's spared anticipatory grip scaling to object size, one of the principal empirical pillars of the model. Based on this new evidence, Schenk rejects the original interpretation of DF's spared ability that was based on segregated processing of object size and argues that DF's spared grip scaling relies on haptic feedback to calibrate visual egocentric cues that relate the posture of the hand to the visible edges of the goal-object. However, a careful consideration of the tasks that Schenk employed reveals some problems with his claim. We suspect that the core issues of this controversy will require a closer examination of the role that cognition plays in the operation of the dorsal and ventral streams in healthy controls and in patient DF.

Validation and Exploration of Instruments for Assessing Public Knowledge of and Attitudes toward Nanotechnology

NASA Astrophysics Data System (ADS)

Lin, Shu-Fen; Lin, Huann-shyang; Wu, Yi-ying

2013-08-01

The purposes of this study were to develop instruments that assess public knowledge of nanotechnology (PKNT), public attitudes toward nanotechnology (PANT) and conduct a pilot study for exploring the relationship between PKNT and PANT. The PKNT test was composed of six scales involving major nanotechnology concepts, including size and scale, structure of matter, size-dependent properties, forces and interactions, tools and instrumentation, as well as science, technology, and society. After item analysis, 26 multiple-choice questions were selected for the PKNT test with a KR-20 reliability of 0.91. Twenty items were developed in the PANT questionnaire which can be classified as scales of trust in government and industry, trust in scientists, and perception of benefit and risk. Cronbach alpha for the PANT questionnaire was 0.70. In a pilot study, 209 citizens, varying in age, were selected to respond to the instruments. Results indicated that about 70 % of respondents did not understand most of the six major concepts involving nanotechnology. The public tended to distrust government and industry and their levels of trust showed no relationship to their levels of knowledge about nanotechnology. However, people perceived that nanotechnology provided high benefits and high risks. Their perceptions of the benefits and risks were positively related with their knowledge level of nanotechnology. People's trust showed a negative relationship to their risk perception. Implications for using these instruments in research are discussed in this paper.

Function and Evolution of Vibrato-like Frequency Modulation in Mammals.

PubMed

Charlton, Benjamin D; Taylor, Anna M; Reby, David

2017-09-11

Why do distantly related mammals like sheep, giant pandas, and fur seals produce bleats that are characterized by vibrato-like fundamental frequency (F0) modulation? To answer this question, we used psychoacoustic tests and comparative analyses to investigate whether this distinctive vocal feature has evolved to improve the perception of formants, key acoustic components of animal calls that encode important information about the caller's size and identity [1]. Psychoacoustic tests on humans confirmed that vibrato-like F0 modulation improves the ability of listeners to detect differences in the formant patterns of synthetic bleat-like stimuli. Subsequent phylogenetically controlled comparative analyses revealed that vibrato-like F0 modulation has evolved independently in six mammalian orders in vocal signals with relatively high F0 and, therefore, low spectral density (i.e., less harmonic overtones). We also found that mammals modulate the vibrato in these calls over greater frequency extents when the number of harmonic overtones per formant is low, suggesting that this is a mechanism to improve formant perception in calls with low spectral density. Our findings constitute the first evidence that formant perception in non-speech sounds is improved by fundamental frequency modulation and provide a mechanism for the convergent evolution of bleat-like calls in mammals. They also indicate that selection pressures for animals to transmit important information encoded by formant frequencies (on size and identity, for example) are likely to have been a key driver in the evolution of mammal vocal diversity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Possibilities and hindrances for prevention of intimate partner violence: perceptions among professionals and decision makers in a Swedish medium-sized town.

PubMed

Jakobsson, A; von Borgstede, C; Krantz, G; Spak, F; Hensing, G

2013-09-01

Intimate partner violence (IPV) is a major public health problem, but few evidence-based prevention programs have yet been implemented. This study explored the perceptions and beliefs of local-level decision makers, social and health-care professionals, and representatives from the police force regarding the possibilities and hindrances for prevention of IPV. An explorative qualitative approach was used, and participants were strategically selected for focus group discussions. The participants, 19 men and 23 women, were professionals or decision makers within health-care services, social welfare, municipal administration, the police force, local industry, and local politicians in a Swedish town of 54,000 inhabitants. The focus group discussions were audio recorded, transcribed verbatim, and thematically analyzed. A manifest content analysis was performed on the text. Preschools, schools, sports associations, workplaces, and the mass media were suggested as possible arenas for prevention measures. The proposed activities included norm building and improved social support structures. Hindrances were conceptualized as societal beliefs and attitudes, shame, silence, gender inequality, the counteracting influence of the media, and lack of resources. The participants demonstrated closeness and distance to IPV, expressed as acceptance or referral of responsibility to others regarding where and by whom prevention measures should be executed. This study gave new insights in the prevailing perceptions of professionals and decision makers of a medium-sized Swedish town, which can be a useful knowledge in future preventive work and contribute to bridge the gap between research and practice.

Anthropometric characteristics of primary school-aged children: accuracy of perception and differences by gender, age and BMI.

PubMed

Cattelino, E; Bina, M; Skanjeti, A M; Calandri, E

2015-11-01

Body perception has been mainly studied in adolescents and adults in relation to eating disorders and obesity because such conditions are usually associated with distortion in the perception of body size. The development of body perception in children was rather neglected despite the relevance of this issue in understanding the aetiology of health eating problems. The main aim of this study was to investigate body weight and body height perception in children by gender, age and body mass index (BMI), taking into account differences among underweight, healthy weight, overweight and obese children. A school-based sample of 572 Italian children (49% boys) aged 6-10 were involved in a cross-sectional survey. Current weight and height were measured by standard protocols, and BMI was calculated and converted in centile categories using the Italian growth curves for children. Perceived weight and height were assessed using visual methods (figures representing children of different weight and height). About a third of the children do not show to have an accurate perception of their weight and height (weight: 36%; height: 32%): as for weight, an error of underestimation prevails and as for height, an error of overestimation prevails. In general, children who have different weight and height from the average tend to perceive their physical characteristics closer to average. However, overweight children underestimate their weight much more than obese children. Distortions in the perception of their physical features, weight and height, appear to be related to the aesthetic models of Western culture. The tendency to underestimate weight, particularly in overweight children, has implications in interventions for health promotion and healthy lifestyle in school-aged children. © 2014 John Wiley & Sons Ltd.

[MANAGEMENT OF HEALTHCARE WASTE IN THE HOSPITAL SETTING. UNDERSTANDING RISK MANAGEMENT].

PubMed

Galimany-Masclans, Jordi; Torres-Egea, Pilar; Sancho-Agredano, Raúl; Girbau-García, Ma Rosa; Fabrellas, Núria; Torrens-Garcia, Ma Llum; Martínez-Estalella, Gemma

2015-05-01

The sanitary waste represents a potential hazard for health workers. Given the high risk of infection in labor accidents, the correct management of sanitary waste minimizes this risk and improves labor and environment conditions. To identify risk perception with health professionals in relation to the advanced sorting and management of healthcare waste (HW). The current study is a descriptive, cross-sectional. The sample size was 177 health workers (nurse assistants, nurses, physicians, lab technicians) from three hospitals in Barcelona (Catalonia). Homemade questionnaire and questions with a free and spontaneous association and incomplete sentences were used to analyze labor variables, perception of risk and personal security through a Likert scale. Using a score from 1 (the lowest perception of risk) to 5 (the high perception of risk) to assess the risk perception, the average value for nurse assistants, nurses, physicians, and lab technicians was 3.71, 3.75, 3.83 and 4.03, respectively. Referring to items with free and spontaneous response association, 44.8% of workers consider HW as a biohazard, 29.6% consider it as waste material, 22.1% state that it must be managed properly and 3.5% described it as unknown residues. The results suggest that all health professionals generally have a perception of high risk. The lab technicians have a higher perception of the real risk of inadequate management of HW A 63.2% report that everyone has to make a proper management to preserve their occupational health; the 59% consider that the HW are a biological risk to the general population and only the 47.8% that are harmful to public health. Although it should be noted that only 44.8% think that HW are toxic and dangerous.

Perceptions of the importance of physical setting in substance abuse treatment.

PubMed

Grosenick, J K; Hatmaker, C M

2000-01-01

Research indicates that architectural design can provide therapeutic effects. Six setting characteristics are considered of primary importance in health-care facilities: comforts and conveniences, safety, attractiveness, size, privacy, and arrangement/location. This study presents the perceptions regarding these and other setting features held by female clients and staff from a substance abuse treatment facility. Results support the importance of these six setting characteristics in influencing clients' treatment goals. Four other setting variables emerged as important to women's recovery: participation in a residential, drug-free, gender-specific program that provides on-site child care. Attention to these variables may provide facilities with an advantage in today's competitive market for clients.

Risk perception as a driver for risk management policies

NASA Astrophysics Data System (ADS)

Carmona, María; Mañez, María

2016-04-01

Risk is generally defined as the "combination of the probability of the occurrence of an event and its negative consequences" ( UNISDR, 2009). However, the perception of a risk differs among cultures regarding different features such as the context,causes, benefits or damage. Risk perception is the subjective valuation of the probability of an event happening and how concerned individuals or groups are with the consequences (Sjöberg, 2004). Our study is based on an existing framework for risk perception (Rehn and Rohrmann, 2000). We analyse the characteristics of the risk perception regarding extreme events (e.g.droughts) and how the perception of the group drives the action to manage the risk. We do this to achieve an overview of the conditions that let stakeholders join each other to improve risk management especially when governments are not reacting properly. For our research, attention is paid on risk perception of Multi-Sector Partnerships not taking into account the individual level of risk perception. We focus on those factors that make risk management effective and increase resilience. Multi-Sector Partnerships, considered as significant governance structures for risk management, might contribute to reduce vulnerability in prone areas to natural hazards and disasters. The Multi-Sector Partnerships used for our research are existing partnerships identified in the cases studies of the European project ENHANCE. We implement a survey to analyse the perception of risk in the case studies. That survey is based on the Cultural Theory (Douglas and Wildavsky, 1982)and the Protection Motivation Theory (Rogers, 1975). We analyse the results using the Qualitative-Comparative Analysis proposed by Ragin in 1987. The results show the main characteristics of a risk culture that are beneficial to manage a risk. Those characteristics are shaped by the perception of risk of the people involved in the partnership, which in turn shapes their risk management. Nevertheless, we have to recognise that there is no "one-size-fit-all" solution and that Multi-Sector Partnerships are shape by the hazard they face and also by the social, political and historical background of the area where they are.

Young Syrian adults' knowledge, perceptions and attitudes to premarital testing.

PubMed

Gharaibeh, H; Mater, F K

2009-12-01

The issue of premarital testing is a controversial and complex issue. Syria is an Islamic country that is moving towards modernization that involves changes in social structures and urbanization of attitudes, beliefs, views and values. The purpose of this study was to identify young Syrian adults' knowledge, perceptions and attitudes about premarital testing. Descriptive, cross-sectional design was utilized. The study was conducted at a mid-sized university in Syria. A stratified simple random sampling was used to recruit the university students in the last 2 years of their graduation. A total of 942 students participated in the study using a questionnaire developed to measure the participants' knowledge, attitudes and perception of premarital testing. Although university students had a considerable knowledge of premarital testing, they had a limited knowledge about certain aspects. Moreover, although they had some positive attitudes, they still had negative attitudes and perceptions towards other aspects of premarital testing. The study results could assist in the development of health education programmes in Syria and other Arab countries to increase their awareness and influence their attitudes towards premarital testing. The study limitation was that the sample was chosen from one part of Syria.

Evaluation of three-dimensional virtual perception of garments

NASA Astrophysics Data System (ADS)

Aydoğdu, G.; Yeşilpinar, S.; Erdem, D.

2017-10-01

In recent years, three-dimensional design, dressing and simulation programs came into prominence in the textile industry. By these programs, the need to produce clothing samples for every design in design process has been eliminated. Clothing fit, design, pattern, fabric and accessory details and fabric drape features can be evaluated easily. Also, body size of virtual mannequin can be adjusted so more realistic simulations can be created. Moreover, three-dimensional virtual garment images created by these programs can be used while presenting the product to end-user instead of two-dimensional photograph images. In this study, a survey was carried out to investigate the visual perception of consumers. The survey was conducted for three different garment types, separately. Questions about gender, profession etc. was asked to the participants and expected them to compare real samples and artworks or three-dimensional virtual images of garments. When survey results were analyzed statistically, it is seen that demographic situation of participants does not affect visual perception and three-dimensional virtual garment images reflect the real sample characteristics better than artworks for each garment type. Also, it is reported that there is no perception difference depending on garment type between t-shirt, sweatshirt and tracksuit bottom.

Medical Group Structural Integration May Not Ensure That Care Is Integrated, From The Patient's Perspective.

PubMed

Kerrissey, Michaela J; Clark, Jonathan R; Friedberg, Mark W; Jiang, Wei; Fryer, Ashley K; Frean, Molly; Shortell, Stephen M; Ramsay, Patricia P; Casalino, Lawrence P; Singer, Sara J

2017-05-01

Structural integration is increasing among medical groups, but whether these changes yield care that is more integrated remains unclear. We explored the relationships between structural integration characteristics of 144 medical groups and perceptions of integrated care among their patients. Patients' perceptions were measured by a validated national survey of 3,067 Medicare beneficiaries with multiple chronic conditions across six domains that reflect knowledge and support of, and communication with, the patient. Medical groups' structural characteristics were taken from the National Study of Physician Organizations and included practice size, specialty mix, technological capabilities, and care management processes. Patients' survey responses were most favorable for the domain of test result communication and least favorable for the domain of provider support for medication and home health management. Medical groups' characteristics were not consistently associated with patients' perceptions of integrated care. However, compared to patients of primary care groups, patients of multispecialty groups had strong favorable perceptions of medical group staff knowledge of patients' medical histories. Opportunities exist to improve patient care, but structural integration of medical groups might not be sufficient for delivering care that patients perceive as integrated. Project HOPE—The People-to-People Health Foundation, Inc.

The utilization of the seven principles for good practices of full-time and adjunct faculty in teaching health & science in community colleges

NASA Astrophysics Data System (ADS)

Musaitif, Linda M.

Purpose. The purpose of this study was to determine the degree to which undergraduate full-time and adjunct faculty members in the health and science programs at community colleges in Southern California utilize the seven principles of good practice as measured by the Faculty Inventory of the Seven Principles for Good Practice in Undergraduate Education. A second purpose was to compare degree of utilization for gender and class size. Methodology. This is a quantitative study wherein there exists a systematic and mathematical assessment of data gathered through the use of a Likert scale survey to process and determine the mathematical model of the use of the principles by the target population of both full-time and adjunct faculty of health/science programs of community colleges in Southern California. Findings. Examination of the data revealed that both full-time and adjunct faculty members of Southern California community colleges perceive themselves a high degree of utilization of the seven principles of good practice. There was no statistically significant data to suggest a discrepancy between full-time and adjunct professors' perceptions among the utilization of the seven principles. Overall, male faculty members perceived themselves as utilizing the principles to a greater degree than female faculty. Data suggest that faculty with class size 60 or larger showed to utilize the seven principles more frequently than the professors with smaller class sizes. Conclusions. Full-time and adjunct professors of the health and sciences in Southern California community colleges perceive themselves as utilizing the seven principles of good practice to a high degree. Recommendations. This study suggests many recommendations for future research, including the degree to which negative economic factors such as budget cuts and demands affect the utilization of the seven principles. Also recommended is a study comparing students' perceptions of faculty's utilization of the seven principles of good practice in the classroom with faculty's self-perception.

Eyes wide open: Pupil size as a proxy for inhibition in the masked-priming paradigm.

PubMed

Geller, Jason; Still, Mary L; Morris, Alison L

2016-05-01

A core assumption underlying competitive-network models of word recognition is that in order for a word to be recognized, the representations of competing orthographically similar words must be inhibited. This inhibitory mechanism is revealed in the masked-priming lexical-decision task (LDT) when responses to orthographically similar word prime-target pairs are slower than orthographically different word prime-target pairs (i.e., inhibitory priming). In English, however, behavioral evidence for inhibitory priming has been mixed. In the present study, we utilized a physiological correlate of cognitive effort never before used in the masked-priming LDT, pupil size, to replicate and extend behavioral demonstrations of inhibitory effects (i.e., Nakayama, Sears, & Lupker, Journal of Experimental Psychology: Human Perception and Performance, 34, 1236-1260, 2008, Exp. 1). Previous research had suggested that pupil size is a reliable indicator of cognitive load, making it a promising index of lexical inhibition. Our pupillometric data replicated and extended previous behavioral findings, in that inhibition was obtained for orthographically similar word prime-target pairs. However, our response time data provided only a partial replication of Nakayama et al. Journal of Experimental Psychology: Human Perception and Performance, 34, 1236-1260, 2008. These results provide converging lines of evidence that inhibition operates in word recognition and that pupillometry is a useful addition to word recognition researchers' toolbox.

Itsy bitsy spider?: Valence and self-relevance predict size estimation.

PubMed

Leibovich, Tali; Cohen, Noga; Henik, Avishai

2016-12-01

The current study explored the role of valence and self-relevance in size estimation of neutral and aversive animals. In Experiment 1, participants who were highly fearful of spiders and participants with low fear of spiders rated the size and unpleasantness of spiders and other neutral animals (birds and butterflies). We found that although individuals with both high and low fear of spiders rated spiders as highly unpleasant, only the highly fearful participants rated spiders as larger than butterflies. Experiment 2 included additional pictures of wasps (not self-relevant, but unpleasant) and beetles. The results of this experiment replicated those of Experiment 1 and showed a similar bias in size estimation for beetles, but not for wasps. Mediation analysis revealed that in the high-fear group both relevance and valence influenced perceived size, whereas in the low-fear group only valence affected perceived size. These findings suggest that the effect of highly relevant stimuli on size perception is both direct and mediated by valence. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

The interaction of glottal-pulse rate and vocal-tract length in judgements of speaker size, sex, and age

NASA Astrophysics Data System (ADS)

Smith, David R. R.; Patterson, Roy D.

2005-11-01

Glottal-pulse rate (GPR) and vocal-tract length (VTL) are related to the size, sex, and age of the speaker but it is not clear how the two factors combine to influence our perception of speaker size, sex, and age. This paper describes experiments designed to measure the effect of the interaction of GPR and VTL upon judgements of speaker size, sex, and age. Vowels were scaled to represent people with a wide range of GPRs and VTLs, including many well beyond the normal range of the population, and listeners were asked to judge the size and sex/age of the speaker. The judgements of speaker size show that VTL has a strong influence upon perceived speaker size. The results for the sex and age categorization (man, woman, boy, or girl) show that, for vowels with GPR and VTL values in the normal range, judgements of speaker sex and age are influenced about equally by GPR and VTL. For vowels with abnormal combinations of low GPRs and short VTLs, the VTL information appears to decide the sex/age judgement.

Social Workers' Perceptions of Job Satisfaction, Interdisciplinary Collaboration, and Organizational Leadership.

PubMed

Marmo, Suzanne; Berkman, Cathy

2018-01-01

To address job satisfaction, and therefore employment retention, of hospice social workers, this study examined how relationships with other members of the interdisciplinary hospice team and perceptions of hospice leadership may be associated with job satisfaction of hospice social workers. The sample of 203 hospice social workers was recruited by e-mailing invitations to hospice social workers identified by hospice directors in three states, use of online social media sites accessed by hospice social workers, and snowball sampling. Study measures included professional experience, hospice characteristics, interdisciplinary collaboration, perception of servant leadership, and intrinsic and extrinsic job satisfaction. Variables significant in the model for intrinsic satisfaction were perception of servant leadership, interdisciplinary collaboration, and feeling valued by the hospice physician. Variables significant in the model for extrinsic satisfaction were perception of servant leadership, interdisciplinary collaboration, feeling valued by the hospice physician, and number of social workers at the hospice. Interdisciplinary collaboration was more important for intrinsic job satisfaction and leadership style was more important for extrinsic job satisfaction. Profit status of the hospice, experience of the social worker, caseload size, and other variables were not significant in either model. These results support previous findings that leadership style of the hospice director and relationships with hospice colleagues are important for hospice social workers' job satisfaction. Such low-cost modifications to the hospice work environment, albeit not simple, may improve job satisfaction of hospice social workers.

Obesity screening in the pediatric emergency department.

PubMed

Vaughn, Lisa M; Nabors, Laura; Pelley, Terri J; Hampton, Rebecca R; Jacquez, Farrah; Mahabee-Gittens, E Melinda

2012-06-01

The purposes of this study were (1) to examine parental perception of childhood obesity and race with measured body mass index (BMI), (2) to determine if parents are receptive to obesity screening in the pediatric emergency department and if receptivity varies by race or weight status, and (3) to determine eating habits that are predictors of obesity. This study is a cross-sectional study, with a convenience sample of 213 patients (aged 4-16 years accompanied by a parent/legal guardian to a pediatric emergency department). Weight and height were obtained, and parents were asked to complete a survey about perception of their child's weight, nutrition, and exercise habits. The current study found that parent perception of weight status was fairly accurate, and perception was predictive of BMI. Race, however, was not predictive of BMI. Parents were generally receptive of weight screening in the pediatric emergency department, and this did not vary as a function of weight status; however, receptivity did vary based on ethnicity, with African American parents being more receptive than white parents. Large portion sizes and the number of times a child eats fast food per week were found to be predictive of obesity. Greater than half of the children presenting to our pediatric emergency department were overweight or obese. Parents were generally accurate in their perception of their child's weight but were still receptive to obesity prevention and screening in the pediatric emergency department.

Effects of set-size and lateral masking in visual search.

PubMed

Põder, Endel

2004-01-01

In the present research, the roles of lateral masking and central processing limitations in visual search were studied. Two search conditions were used: (1) target differed from distractors by presence/absence of a simple feature; (2) target differed by relative position of the same components only. The number of displayed stimuli (set-size) and the distance between neighbouring stimuli were varied as independently as possible in order to measure the effect of both. The effect of distance between stimuli (lateral masking) was found to be similar in both conditions. The effect of set-size was much larger for relative position stimuli. The results support the view that perception of relative position of stimulus components is limited mainly by the capacity of central processing.

Persistent negative illness perceptions despite long-term biochemical control of acromegaly: novel application of the drawing test.

PubMed

Tiemensma, Jitske; Pereira, Alberto M; Romijn, Johannes A; Broadbent, Elizabeth; Biermasz, Nienke R; Kaptein, Adrian A

2015-05-01

Patients with acromegaly have persistent complaints despite long-term biochemical control. Drawings can be used to assess patients' perceptions about their disease. We aimed to explore the utility of the drawing test and its relation to illness perceptions and quality of life (QoL) in patients after long-term remission of acromegaly. A cross-sectional study was conducted to evaluate the utility of the drawing test. A total of 50 patients after long-term remission (mean±s.e.m., 16±1.2 years) of acromegaly were included in this study. Patients completed the drawing test (two retrospective drawings of their body perception before acromegaly and during the active phase of acromegaly, and one drawing on the current condition after long-term remission), Illness Perception Questionnaire-Revised, Physical Symptom Checklist, EuroQoL-5D, and AcroQoL. Patients perceived a dramatic change in body size during the active state of the disease compared with the healthy state before the awareness of acromegaly. Patients reported that their body did not completely return to the original proportions after long-term remission. In addition, larger drawings indicated more negative consequences (P<0.05), a higher score on emotional representations (P<0.05), and more perceived symptoms that were attributed to acromegaly (P<0.01). Larger drawings also indicated more impaired QoL, especially disease-specific QoL (all P<0.05). There are strong correlations among the drawing test, illness perceptions, and QoL. The drawing test appears to be a novel and relatively easy tool to assess the perception of patients after long-term remission of acromegaly. The assessment of drawings may enable health care providers to appreciate the perceptions of patients with long-term remission of acromegaly, and enable discussion of symptoms and remission. © 2015 European Society of Endocrinology.

Health symptoms in relation to temperature, humidity, and self-reported perceptions of climate in New York City residential environments

NASA Astrophysics Data System (ADS)

Quinn, Ashlinn; Shaman, Jeffrey

2017-07-01

Little monitoring has been conducted of temperature and humidity inside homes despite the fact that these conditions may be relevant to health outcomes. Previous studies have observed associations between self-reported perceptions of the indoor environment and health. Here, we investigate associations between measured temperature and humidity, perceptions of indoor environmental conditions, and health symptoms in a sample of New York City apartments. We measured temperature and humidity in 40 New York City apartments during summer and winter seasons and collected survey data from the households' residents. Health outcomes of interest were (1) sleep quality, (2) symptoms of heat illness (summer season), and (3) symptoms of respiratory viral infection (winter season). Using mixed-effects logistic regression models, we investigated associations between the perceptions, symptoms, and measured conditions in each season. Perceptions of indoor temperature were significantly associated with measured temperature in both the summer and the winter, with a stronger association in the summer season. Sleep quality was inversely related to measured and perceived indoor temperature in the summer season only. Heat illness symptoms were associated with perceived, but not measured, temperature in the summer season. We did not find an association between any measured or perceived condition and cases of respiratory infection in the winter season. Although limited in size, the results of this study reveal that indoor temperature may impact sleep quality, and that thermal perceptions of the indoor environment may indicate vulnerability to heat illness. These are both important avenues for further investigation.

Cultural values and health service quality in China.

PubMed

Polsa, Pia; Fuxiang, Wei; Sääksjärvi, Maria; Shuyuan, Pei

2013-01-01

Several service quality studies show how cultural features may influence the way service quality is perceived. However, few studies specifically describe culture's influence on health service quality. Also, there are few studies that take into account patients' health service quality perceptions. This article seeks to present a first step to fill these gaps by examining patients' cultural values and their health service quality assessments. The study draws on published work and applies its ideas to Chinese healthcare settings. Data consist of hospital service perceptions in the People's Republic of China (PRC), a society that is socially, economically and culturally undergoing major changes. In total, 96 patients were surveyed. Data relationships were tested using partial least square (PLS) analysis. Findings show that Chinese patients' cultural values and their health service assessments are related and that the cultural values themselves seem to be changing. Additionally, further analyses provided interesting results pointing to which cultural values influenced service quality perceptions. The strongest service quality predictor was power distance. The sample is relatively small and collected from only one major hospital in China. Therefore, future research should extend the sample size and scope. Follow-up research could also include cross-cultural investigations of perceived health service quality to substantiate cultural influences on health service quality perceptions. In line with similar research in other contexts, the study confirms that power distance has a significant relationship with service quality perceptions. The study contributes to existing health service literature by offering patients' views on health service quality and by describing relationships between health service perceptions and cultural values--the study's main contribution.

Acute effects of THC on time perception in frequent and infrequent cannabis users.

PubMed

Sewell, R Andrew; Schnakenberg, Ashley; Elander, Jacqueline; Radhakrishnan, Rajiv; Williams, Ashley; Skosnik, Patrick D; Pittman, Brian; Ranganathan, Mohini; D'Souza, D Cyril

2013-03-01

Cannabinoids have been shown to alter time perception, but existing literature has several limitations. Few studies have included both time estimation and production tasks, few control for subvocal counting, most had small sample sizes, some did not record subjects' cannabis use, many tested only one dose, and used either oral or inhaled administration of Δ⁹-tetrahydrocannabinol (THC), leading to variable pharmacokinetics, and some used whole-plant cannabis containing cannabinoids other than THC. Our study attempted to address these limitations. This study aims to characterize the acute effects of THC and frequent cannabis use on seconds-range time perception. THC was hypothesized to produce transient, dose-related time overestimation and underproduction. Frequent cannabis smokers were hypothesized to show blunted responses to these alterations. IV THC was administered at doses from 0.015 to 0.05 mg/kg to 44 subjects who participated in several double-blind, randomized, counterbalanced, crossover, placebo-controlled studies. Visual time estimation and production tasks in the seconds range were presented to subjects three times on each test day. All doses induced time overestimation and underproduction. Chronic cannabis use had no effect on baseline time perception. While infrequent/nonsmokers showed temporal overestimation at medium and high doses and temporal underproduction at all doses, frequent cannabis users showed no differences. THC effects on time perception were not dose related. A psychoactive dose of THC increases internal clock speed as indicated by time overestimation and underproduction. This effect is not dose related and is blunted in chronic cannabis smokers who did not otherwise have altered baseline time perception.

Psychological barriers to optimal insulin therapy: more concerns in adolescent females than males

PubMed Central

Wisting, Line; Bang, Lasse; Skrivarhaug, Torild; Dahl-Jørgensen, Knut; Rø, Øyvind

2016-01-01

Objective The aim of this study is to investigate psychological barriers (illness perceptions, insulin beliefs, and coping strategies) to optimal insulin therapy among adolescents with type 1 diabetes (T1D), with a specific focus on gender differences and mode of treatment (insulin pump vs pen). Methods A total of 105 males and females (12–20 years) participated in this study. The Brief Illness Perception Questionnaire, the Beliefs about Medicines Questionnaire, and the Adolescent Coping Orientation for Problem Experiences were completed. Additionally, diabetes clinical data were collected by the Norwegian Childhood Diabetes Registry. Results Females had significantly more negative illness perceptions than males on all dimensions (p<0.05), with moderate-to-large effect sizes. Regarding insulin beliefs, females scored significantly higher than males on insulin concern (p<0.001), indicating more concerns about insulin. There were no significant gender differences on perceptions of insulin necessity. Finally, females scored significantly higher on the coping strategies being social and solving family problems (p<0.01), indicating more positive coping among females than males for these subscales. In terms of treatment mode, the only statistically significant difference in the psychological aspects was for the illness perception treatment control, with patients using insulin pen reporting more negative perceptions on this dimension than patients using insulin pump. Conclusions Addressing psychological aspects may be a clinically important supplement to standard somatic T1D care. The consistent finding of gender differences across the psychological measures implies that a tailored treatment approach for males and females with T1D may be warranted. PMID:27403325

Threat of the thin-ideal body image and body malleability beliefs: effects on body image self-discrepancies and behavioral intentions.

PubMed

Arciszewski, Thomas; Berjot, Sophie; Finez, Lucie

2012-06-01

This study examined the effect of the threat aroused by the perception of thin-ideal images combined with beliefs about the malleability of the body on perceived/objective, ideal/objective and ought/objective body image self-discrepancies. An experimental computer program enabled women (N=82) to artificially increase or decrease the shape of their own body (previously photographed) in response to questions about their "actual", "ideal" and "ought" body self-perceptions. As predicted, results showed that women had greater body self-discrepancies when confronted with threatening thin ideals, regardless of their body mass index. The size of this trend depended on the way they were made to think of their body (malleable vs. fixed). Findings also suggested a possible relationship between body self-representations and eating behaviors or intentions. The impact of thin-ideal threats and body malleability beliefs on body perception is discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.

Bottom-up and top-down attentional contributions to the size congruity effect.

PubMed

Sobel, Kenith V; Puri, Amrita M; Faulkenberry, Thomas J

2016-07-01

The size congruity effect refers to the interaction between the numerical and physical (i.e., font) sizes of digits in a numerical (or physical) magnitude selection task. Although various accounts of the size congruity effect have attributed this interaction to either an early representational stage or a late decision stage, only Risko, Maloney, and Fugelsang (Attention, Perception, & Psychophysics, 75, 1137-1147, 2013) have asserted a central role for attention. In the present study, we used a visual search paradigm to further study the role of attention in the size congruity effect. In Experiments 1 and 2, we showed that manipulating top-down attention (via the task instructions) had a significant impact on the size congruity effect. The interaction between numerical and physical size was larger for numerical size comparison (Exp. 1) than for physical size comparison (Exp. 2). In the remaining experiments, we boosted the feature salience by using a unique target color (Exp. 3) or by increasing the display density by using three-digit numerals (Exps. 4 and 5). As expected, a color singleton target abolished the size congruity effect. Searching for three-digit targets based on numerical size (Exp. 4) resulted in a large size congruity effect, but search based on physical size (Exp. 5) abolished the effect. Our results reveal a substantial role for top-down attention in the size congruity effect, which we interpreted as support for a shared-decision account.

Job satisfaction among immigrant nurses in Israel and the United States of America.

PubMed

Itzhaki, M; Ea, E; Ehrenfeld, M; Fitzpatrick, J J

2013-03-01

The aim of this study is to examine perceptions of job satisfaction among immigrant registered nurses (RNs) in Israel and the USA. Former Soviet Union (FSU) RNs in Israel and Filipino RNs in the USA make up the majority of the immigrant nursing workforce in their host countries. However, little is known about their perception of job satisfaction. Data were gathered using the Index of Work Satisfaction Scale among 71 FSU RNs recruited from three different courses in baccalaureate and master's degree programmes at a central Israeli university, and 96 Filipino RNs attending a national convention hosted by the Philippine Nurses Association of America. The required sample size was obtained by means of the WINPEPI COMPARE2 program, used to determine power and sample size for comparisons of two groups in cross-sectional designs. The findings show that FSU RNs perceived pay and professional status as important, although they were least satisfied with pay. For Filipino RNs, organizational policies and interactions were most important and they were least satisfied by task requirements. Although the average length of residence in the host country was similar in the two samples, significant differences were found between FSU and Filipino RNs in selected demographic variables and components of job satisfaction. Different characteristics of immigrant RNs affect their distinct perceptions of job satisfaction. As successful adjustment of international immigrant RNs to their workplace could enhance perceptions of job satisfaction, nursing managers should support professional advancement of immigrant RNs through mentorship and educational programmes. There is a need to conduct longitudinal studies among international immigrant RNs in order to better understand changes in their job satisfaction over time and contributing factors. Generalization of the findings is limited, because a convenience sample was used to recruit FSU and Filipino immigrant RNs. © 2012 The Authors. International Nursing Review © 2012 International Council of Nurses.

Some Supporting Evidence for Accurate Multivariate Perceptions with Chernoff Faces, Project 547.

ERIC Educational Resources Information Center

Wainer, Howard

A scheme, using features in a cartoon-like human face to represent variables, is tested as to its ability to graphically depict multivariate data. A factor analysis of Harman's "24 Psychological Tests" was performed and yielded four orthogonal factors. Nose width represented the loading on Factor 1; eye size on Factor 2; curve of mouth…

The Problem of Scale in the Interpretation of Pictorial Representations of Cell Structure

ERIC Educational Resources Information Center

Vlaardingerbroek, Barend; Taylor, Neil; Bale, Colin

2014-01-01

Diagrams feature prominently in science education, and there has been an increase in research focusing on students' use of them in knowledge construction. This paper reports on an investigation into first year university students' perceptions of scale and size at the cellular level. It was found that many students appeared to tacitly assume that…

Girls Who Perceive Themselves as Competent: Some Antecedents and Correlates

ERIC Educational Resources Information Center

Baruch, Grace K.

1976-01-01

Self-perceptions of competence of white, middle-class fifth- and tenth-grade girls were examined in relation to (a) maternal variables and (b) self-esteem and anticipated role pattern (career aspirations and desired family size). Subjects were 79 fifth-graders and 51 of their mothers, and 49 tenth-graders and 38 of their mothers. Results are…

The Effect of Brand Identification on Alumni Supportive Behaviors

ERIC Educational Resources Information Center

Stephenson, Amber L.

2013-01-01

The purpose of this study was to explore the relationship of brand identification and supportive behaviors for alumni of a medium-sized state-run public institution of higher education in the mid-Atlantic region of the US. The research examined the perceptions of donor and non-donor alumni of a state-run public institution of higher education to…

Students' Perceptions of School Climate in the U.S. and China

ERIC Educational Resources Information Center

Yang, Chunyan; Bear, George G.; Chen, Fang Fang; Zhang, Wei; Blank, Jessica C.; Huang, Xishan

2013-01-01

Although the construct of student climate has been studied extensively in the United States, we know little about how school climate is perceived in other countries. With large class sizes yet higher academic achievement and less disruptive and aggressive student behaviors, schools in China present a contrast to many schools in the United States.…

Perceptions of Educational Opportunities in Small Schools in Rural Australia and Canada

ERIC Educational Resources Information Center

Stevens, Ken

2009-01-01

Australia and Canada are large countries with small populations relative to their size, in which a not inconsiderable number of citizens live beyond major centres of population. In both resource-based economies, the provision of quality education in rural schools is an important part of the national social and economic infrastructure. This article…

Relationships between Student Perception of Teacher-Student Relations and PISA Results in Mathematics and Science

ERIC Educational Resources Information Center

Mikk, Jaan; Krips, Heiki; Säälik, Ülle; Kalk, Karmen

2016-01-01

Teacher-student relations have a significant correlation with student motivation, academic performance and discipline. For example, the meta-analysis by Hattie (2009) revealed an effect size of d = 0.72 for the effect of relations on achievement, and the meta-analysis by Finn, Schrodt, Witt, Elledge, Jernberg & Larson ("Communication…

Tablet PCs in a Paperless Classroom: Student and Teacher Perceptions on Screen Size

ERIC Educational Resources Information Center

Runnels, Judith; Rutson-Griffiths, Arthur

2013-01-01

A paperless classroom, when all materials required to complete a class are available in an electronic form, has been shown to have positive impacts on student and teacher motivation, engagement, productivity, and efficiency. Recent trends suggest that of all of the technological tools available, tablet PCs can support many aspects of a paperless…

The Effects of Virtual Coaching on Teacher Candidates' Perceptions and Concerns Regarding On-Demand Corrective Feedback

ERIC Educational Resources Information Center

Wake, Donna; Dailey, Debbie; Cotabish, Alicia; Benson, Tammy

2017-01-01

A virtual coaching intervention utilizing Skype and Bluetooth (Bug-in-the-Ear) technology provided immediate corrective feedback to non-traditional teacher candidates during a semester-long internship experience. Participants completed their student teaching internship as a requirement of a teacher preparation program at a mid-size Southeastern…

Perception of Auditory-Visual Distance Relations by 5-Month-Old Infants.

ERIC Educational Resources Information Center

Pickens, Jeffrey

1994-01-01

Sixty-four infants viewed side-by-side videotapes of toy trains (in four visual conditions) and listened to sounds at increasing or decreasing amplitude designed to match one of the videos. Results suggested that five-month olds were sensitive to auditory-visual distance relations and that change in size was an important visual depth cue. (MDM)

An Analysis of the Perceptions and Resources of Large University Classes

ERIC Educational Resources Information Center

Cash, Ceilidh Barlow; Letargo, Jessa; Graether, Steffen P.; Jacobs, Shoshanah R.

2017-01-01

Large class learning is a reality that is not exclusive to the first-year experience at midsized, comprehensive universities; upper-year courses have similarly high enrollment, with many class sizes greater than 200 students. Research into the efficacy and deficiencies of large undergraduate classes has been ongoing for more than 100 years, with…

Give or Take a Few? Comparing Measured and Self-Reported Height and Weight as Correlates of Social Physique Anxiety

ERIC Educational Resources Information Center

Gay, Jennifer; Monsma, Eva V.; Torres-McGehee, Toni

2009-01-01

Statistically controlling for physical size is common practice, especially in self-perception studies uncovering the etiology of maladaptive behaviors, such as eating disorders. For example, social physique anxiety (SPA)--apprehension about social evaluations while presenting oneself in front of others (Leary, 1992)--is a prominent correlate of…

What can child silhouette data tell us? Exploring links to parenting, food and activity behaviors, and maternal concerns

USDA-ARS?s Scientific Manuscript database

Purpose: A study of resiliency to overweight explored how child silhouettes (maternal perception of child’s body size) related to child BMI, maternal concerns, parenting styles and practices. Methods: In a diverse, multi-state sample, 175 low-income mother-child (ages 3-11) dyads were assessed for...

Using Focus Groups to Identify Factors Affecting Healthful Weight Maintenance in Latino Immigrants

ERIC Educational Resources Information Center

Greaney, Mary L.; Lees, Faith D.; Lynch, Breanna; Sebelia, Linda; Greene, Geoffrey W.

2012-01-01

Objective: To explore (1) how migration influenced physical activity and dietary behaviors among Latino immigrants and (2) participants' perception of concepts related to a Health at Every Size (HAES) approach to weight maintenance (mindful eating, taking care of oneself). Methods: Four focus groups (n = 35), homogenous by sex, were conducted in…

School Nutrition Professionals' Usage and Perceptions of USDA Recipes and the Impact of Student Enrollment

ERIC Educational Resources Information Center

Rushing, Keith; Johnson, J. T.

2015-01-01

Purpose/Objectives: The purpose of this study was to explore the frequency of usage of the United States Department of Agriculture (USDA) Recipes for Schools and investigate factors influencing their usage. The relationship between these variables and school district size (student enrollment) was also investigated. Methods: An expert panel…

University Faculty Perceptions and Utilization of Popular Culture in the Classroom

ERIC Educational Resources Information Center

Peacock, Jessica; Covino, Ralph; Auchter, Jessica; Boyd, Jennifer; Klug, Hope; Laing, Craig; Irvin, Lindsay

2018-01-01

This article discusses results of a survey on the utilization of and attitudes and beliefs towards the use of popular culture among faculty in higher education. A total of 212 faculty members from a mid-sized public regional university provided responses, with the majority indicating that they utilize popular culture in their classroom teaching…

Ascending Bloom's Pyramid: Fostering Student Creativity and Innovation in Academic Library Spaces

ERIC Educational Resources Information Center

Bieraugel, Mark; Neill, Stern

2017-01-01

Our research examined the degree to which behaviors and learning associated with creativity and innovation were supported in five academic library spaces and three other spaces at a mid-sized university. Based on survey data from 226 students, we apply a number of statistical techniques to measure student perceptions of the types of learning and…

The Emotions of Socialization-Related Learning: Understanding Workplace Adaptation as a Learning Process.

ERIC Educational Resources Information Center

Reio, Thomas G., Jr.

The influence of selected discrete emotions on socialization-related learning and perception of workplace adaptation was examined in an exploratory study. Data were collected from 233 service workers in 4 small and medium-sized companies in metropolitan Washington, D.C. The sample members' average age was 32.5 years, and the sample's racial makeup…

Percepción del tamaño de la Luna

NASA Astrophysics Data System (ADS)

Lares, M.

When Lunar astronomical phenomena are communicated to the general public, changes in the Lunar disc size are usually bring out. However, the perception of such change is different to the change itself. In this work a quantification of the sensation of change in the area is proposed, based on results from cognitive sciences. FULL TEXT IN SPANISH

Action-specific effects in aviation: what determines judged runway size?

PubMed

Gray, Rob; Navia, José Antonio; Allsop, Jonathan

2014-01-01

Several recent studies have shown that the performance of a skill that involves acting on a goal object can influence one's judgment of the size of that object. The present study investigated this effect in an aviation context. Novice pilots were asked to perform a series of visual approach and landing manoeuvres in a flight simulator. After each landing, participants next performed a task in which runway size was judged for different simulated altitudes. Gaze behaviour and control stick kinematics were also analyzed. There were significant relationships between judged runway size and multiple action-related variables including touchdown velocity, time fixating the runway, and the magnitude and frequency of control inputs. These findings suggest that relationship between the perception of a target object and action is not solely determined by performance success or failure but rather involves a relationship between multiple variables that reflect the actor's ability.

Depth reversals in stereoscopic displays driven by apparent size

NASA Astrophysics Data System (ADS)

Sacher, Gunnar; Hayes, Amy; Thornton, Ian M.; Sereno, Margaret E.; Malony, Allen D.

1998-04-01

In visual scenes, depth information is derived from a variety of monocular and binocular cues. When in conflict, a monocular cue is sometimes able to override the binocular information. We examined the accuracy of relative depth judgments in orthographic, stereoscopic displays and found that perceived relative size can override binocular disparity as a depth cue in a situation where the relative size information is itself generated from disparity information, not from retinal size difference. A size discrimination task confirmed the assumption that disparity information was perceived and used to generate apparent size differences. The tendency for the apparent size cue to override disparity information can be modulated by varying the strength of the apparent size cue. In addition, an analysis of reaction times provides supporting evidence for this novel depth reversal effect. We believe that human perception must be regarded as an important component of stereoscopic applications. Hence, if applications are to be effective and accurate, it is necessary to take into account the richness and complexity of the human visual perceptual system that interacts with them. We discuss implications of this and similar research for human performance in virtual environments, the design of visual presentations for virtual worlds, and the design of visualization tools.

On spatial attention and its field size on the repulsion effect

PubMed Central

Cutrone, Elizabeth K.; Heeger, David J.; Carrasco, Marisa

2018-01-01

We investigated the attentional repulsion effect—stimuli appear displaced further away from attended locations—in three experiments: one with exogenous (involuntary) attention, and two with endogenous (voluntary) attention with different attention-field sizes. It has been proposed that differences in attention-field size can account for qualitative differences in neural responses elicited by attended stimuli. We used psychophysical comparative judgments and manipulated either exogenous attention via peripheral cues or endogenous attention via central cues and a demanding rapid serial visual presentation task. We manipulated the attention field size of endogenous attention by presenting streams of letters at two specific locations or at two of many possible locations during each block. We found a robust attentional repulsion effect in all three experiments: with endogenous and exogenous attention and with both attention-field sizes. These findings advance our understanding of the influence of spatial attention on the perception of visual space and help relate this repulsion effect to possible neurophysiological correlates.

Hispanic maternal influences on daughters' unhealthy weight control behaviors: The role of maternal acculturation, adiposity, and body image disturbances.

PubMed

Olvera, Norma; Matthews-Ewald, Molly R; McCarley, Kendall; Scherer, Rhonda; Posada, Alexandria

2016-12-01

This study examined whether maternal adiposity, acculturation, and perceived-ideal body size discrepancy for daughters were associated with daughters' engagement in unhealthy weight control behaviors. A total of 97 Hispanic mother-daughter dyads completed surveys, rated a figure scale, and had their height, weight, and adiposity assessed. Mothers (M age =39.00, SD=6.20 years) selected larger ideal body sizes for their daughters (M age =11.12, SD=1.53 years) than their daughters selected for themselves. Mothers had a smaller difference between their perception of their daughters' body size and ideal body size compared to the difference between their daughters' selection of their perceived and ideal body size. More acculturated mothers and those mothers with larger waist-to-hip ratios were more likely to have daughters who engaged in unhealthy weight control behaviors. These findings highlight the relevant role that maternal acculturation and adiposity may have in influencing daughters' unhealthy weight control behaviors. Published by Elsevier Ltd.

A pilot study on body image, attractiveness and body size in Gambians living in an urban community.

PubMed

Siervo, M; Grey, P; Nyan, O A; Prentice, A M

2006-06-01

We investigated the attitudinal and perceptual components of body image and its link with body mass index (BMI) in a sample of urban Gambians. We also looked at cross-cultural differences in body image and views on attractiveness between Gambians and Americans. Four groups of 50 subjects were assessed: men 14- 25y (YM); women 14-25y (YW); men 35-50y (OM); women 35-50y (OW). Socio-economic status, education, healthy lifestyle and western influences were investigated. Height and weight were measured. Body dissatisfaction was assessed with the body dissatisfaction scale of the Eating Disorder Inventory. Perceptions of body image and attractiveness were assessed using the Body Image Assessment for Obesity (BIA-O) and Figure Rating Scale (FRS). Different generations of Gambians had very different perceptions and attitudes towards obesity. Current body size was realistically perceived and largely well tolerated. Older women had a higher body discrepancy (current minus ideal body size) than other groups (p<0.001). Regression analysis showed they were not worried about their body size until they were overweight (BMI=27.8 kg/m2), whilst OM, YM and YW started to be concerned at a BMI respectively of 22.9, 19.8 and 21.5 kg/m2. A cross-cultural comparison using published data on FRS showed that Gambians were more obesity tolerant than black and white Americans. The Gambia is a country in the early stage of demographic transitions but in urban areas there is an increase in obesity prevalence. Inherent tensions between the preservation of cultural values and traditional habits, and raising awareness of the risks of obesity, may limit health interventions to prevent weight gain.

See food diet? Cultural differences in estimating fullness and intake as a function of plate size.

PubMed

Peng, Mei; Adam, Sarah; Hautus, Michael J; Shin, Myoungju; Duizer, Lisa M; Yan, Huiquan

2017-10-01

Previous research has suggested that manipulations of plate size can have a direct impact on perception of food intake, measured by estimated fullness and intake. The present study, involving 570 individuals across Canada, China, Korea, and New Zealand, is the first empirical study to investigate cultural influences on perception of food portion as a function of plate size. The respondents viewed photographs of ten culturally diverse dishes presented on large (27 cm) and small (23 cm) plates, and then rated their estimated usual intake and expected fullness after consuming the dish, using 100-point visual analog scales. The data were analysed with a mixed-model ANCOVA controlling for individual BMI, liking and familiarity of the presented food. The results showed clear cultural differences: (1) manipulations of the plate size had no effect on the expected fullness or the estimated intake of the Chinese and Korean respondents, as opposed to significant effects in Canadians and New Zealanders (p < 0.05); (2) Canadian (88.91 ± 0.42) and New Zealanders (90.37 ± 0.41) reported significantly higher estimated intake ratings than Chinese (80.80 ± 0.38) or Korean (81.69 ± 0.44; p < 0.05), notwithstanding the estimated fullness ratings from the Western respondents were comparable or even higher than those from the Asian respondents. Overall, these findings, from a cultural perspective, support the notion that estimation of fullness and intake are learned through dining experiences, and highlight the importance of considering eating environments and contexts when assessing individual behaviours relating to food intake. Copyright © 2017 Elsevier Ltd. All rights reserved.

Development and validation of a toddler silhouette scale.

PubMed

Hager, Erin R; McGill, Adrienne E; Black, Maureen M

2010-02-01

The purpose of this study is to develop and validate a toddler silhouette scale. A seven-point scale was developed by an artist based on photographs of 15 toddlers (6 males, 9 females) varying in race/ethnicity and body size, and a list of phenotypic descriptions of toddlers of varying body sizes. Content validity, age-appropriateness, and gender and race/ethnicity neutrality were assessed among 180 pediatric health professionals and 129 parents of toddlers. Inter- and intrarater reliability and concurrent validity were assessed by having 138 pediatric health professionals match the silhouettes with photographs of toddlers. Assessments of content validity revealed that most health professionals (74.6%) and parents of toddlers (63.6%) ordered all seven silhouettes correctly, and interobserver agreement for weight status classification was high (kappa = 0.710, r = 0.827, P < 0.001). Most respondents reported that the scale represented toddlers aged 12-36 months (89%) and was gender (68.5%) and race/ethnicity (77.3%) neutral. The inter-rater reliability, based on matching silhouettes with photographs, was 0.787 (Cronbach's alpha) and the intrarater reliability was 0.855 (P < 0.001). The concurrent validity, based on the correlation between silhouette choice and the weight-for-length percentile of each toddler's photograph, was 0.633 (P < 0.001). In conclusion, a valid and reliable toddler silhouette scale that may be used for male or female toddlers, aged 12-36 months, of varying race/ethnicity was developed and evaluated. This scale may be used clinically or in research settings to assess parents' perception of and satisfaction with their toddler's body size. Interventions can be targeted toward parents who have inaccurate perceptions of or are dissatisfied with their toddler's body size.

Pointing to double-step visual stimuli from a standing position: motor corrections when the speed-accuracy trade-off is unexpectedly modified in-flight. A breakdown of the perception-action coupling.

PubMed

Fautrelle, L; Barbieri, G; Ballay, Y; Bonnetblanc, F

2011-10-27

The time required to complete a fast and accurate movement is a function of its amplitude and the target size. This phenomenon refers to the well known speed-accuracy trade-off. Some interpretations have suggested that the speed-accuracy trade-off is already integrated into the movement planning phase. More specifically, pointing movements may be planned to minimize the variance of the final hand position. However, goal-directed movements can be altered at any time, if for instance, the target location is changed during execution. Thus, one possible limitation of these interpretations may be that they underestimate feedback processes. To further investigate this hypothesis we designed an experiment in which the speed-accuracy trade-off was unexpectedly varied at the hand movement onset by modifying separately the target distance or size, or by modifying both of them simultaneously. These pointing movements were executed from an upright standing position. Our main results showed that the movement time increased when there was a change to the size or location of the target. In addition, the terminal variability of finger position did not change. In other words, it showed that the movement velocity is modulated according to the target size and distance during motor programming or during the final approach, independently of the final variability of the hand position. It suggests that when the speed-accuracy trade-off is unexpectedly modified, terminal feedbacks based on intermediate representations of the endpoint velocity are used to monitor and control the hand displacement. There is clearly no obvious perception-action coupling in this case but rather intermediate processing that may be involved. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

Wind-driven particle mobility on Mars: Insights from Mars Exploration Rover observations at "El Dorado" and surroundings at Gusev Crater

USGS Publications Warehouse

Sullivan, R.; Arvidson, R.; Bell, J.F.; Gellert, Ralf; Golombek, M.; Greeley, R.; Herkenhoff, K.; Johnson, J.; Thompson, S.; Whelley, P.; Wray, J.

2008-01-01

The ripple field known as 'El Dorado' was a unique stop on Spirit's traverse where dust-raising, active mafic sand ripples and larger inactive coarse-grained ripples interact, illuminating several long-standing issues of Martian dust mobility, sand mobility, and the origin of transverse aeolian ridges. Strong regional wind events endured by Spirit caused perceptible migration of ripple crests in deposits SSE of El Dorado, erasure of tracks in sandy areas, and changes to dust mantling the site. Localized thermal vortices swept across El Dorado, leaving paths of reduced dust but without perceptibly damaging nearly cohesionless sandy ripple crests. From orbit, winds responsible for frequently raising clay-sized dust into the atmosphere do not seem to significantly affect dunes composed of (more easily entrained) sand-sized particles, a long-standing paradox. This disparity between dust mobilization and sand mobilization on Mars is due largely to two factors: (1) dust occurs on the surface as fragile, low-density, sand-sized aggregates that are easily entrained and disrupted, compared with clay-sized air fall particles; and (2) induration of regolith is pervasive. Light-toned bed forms investigated at Gusev are coarse-grained ripples, an interpretation we propose for many of the smallest linear, light-toned bed forms of uncertain origin seen in high-resolution orbital images across Mars. On Earth, wind can organize bimodal or poorly sorted loose sediment into coarse-grained ripples. Coarse-grained ripples could be relatively common on Mars because development of durable, well-sorted sediments analogous to terrestrial aeolian quartz sand deposits is restricted by the lack of free quartz and limited hydraulic sediment processing. Copyright 2008 by the American Geophysical Union.

The Impact of Congruency Between Preferred and Actual Learning Environments on Tenth Graders' Science Literacy in Taiwan

NASA Astrophysics Data System (ADS)

Chang, Chun-Yen; Yeh, Ting-Kuang; Lin, Chun-Yen; Chang, Yueh-Hsia; Chen, Chia-Li D.

2010-08-01

This study explored the effects of congruency between preferred and actual learning environment (PLE & ALE) perceptions on students' science literacy in terms of science concepts, attitudes toward science, and the understanding of the nature of science in an innovative curriculum of High Scope Project, namely Sci-Tech Mind and Humane Heart (STMHH). A pre-/post-treatment experiment was conducted with 34 Taiwanese tenth graders involved in this study. Participating students' preferred learning environment perception and pre-instruction scientific literacy were evaluated before the STMHH curriculum. Their perceptions toward the actual STMHH learning environment and post-instruction scientific literacy were also examined after the STMHH. Students were categorized into two groups; "preferred alignment with actual learning environment" (PAA) and "preferred discordant with actual learning environment" (PDA), according to their PLEI and ALEI scores. The results of this study revealed that most of the students in this study preferred learning in a classroom environment where student-centered and teacher-centered learning environments coexisted. Furthermore, the ANCOVA analysis showed marginally statistically significant difference between groups in terms of students' post-test scores on scientific literacy with the students' pre-test scores as the covariate. As a pilot study with a small sample size aiming to probe the research direction of this problem, the result of marginally statistically significant and approaching large sized effect magnitude is likely to implicate that the congruency between preferred and actual learning environments on students' scientific literacy is noteworthy. Future study of this nature appears to merit further replications and investigations.

Medical Student Perceptions of the Learning Environment: Learning Communities Are Associated With a More Positive Learning Environment in a Multi-Institutional Medical School Study.

PubMed

Smith, Sunny D; Dunham, Lisette; Dekhtyar, Michael; Dinh, An; Lanken, Paul N; Moynahan, Kevin F; Stuber, Margaret L; Skochelak, Susan E

2016-09-01

Many medical schools have implemented learning communities (LCs) to improve the learning environment (LE) for students. The authors conducted this study to determine whether a relationship exists between medical student perceptions of the LE and presence of LCs during the preclerkship years. Students from 24 schools participating in the American Medical Association Learning Environment Study completed the 17-item Medical Student Learning Environment Survey (MSLES) at the end of their first and second years of medical school between 2011 and 2013. Mean total MSLES scores and individual item scores at the end of the first and second years in schools with and without LCs were compared with t tests, and effect sizes were calculated. Mixed-effects longitudinal models were used to control for student demographics and random school and student effects on the relationship between LC status and MSLES score. A total of 4,980 students (81% of 6,148 matriculants) from 18 schools with LCs and 6 without LCs participated. Mean [SD] MSLES scores were significantly higher in LC schools compared with non-LC schools at the end of year one (3.72 [0.44] versus 3.57 [0.43], P < .001) and year two (3.69 [0.49] versus 3.42 [0.54], P < .001). The effect size increased from 0.35 (small) at the end of year one to 0.53 (medium) at the end of year two. This large multi-institutional cohort study found that LCs at medical schools were associated with more positive perceptions of the LE by preclerkship students.

The impact of structural packaging design on young adult smokers' perceptions of tobacco products.

PubMed

Borland, Ron; Savvas, Steven; Sharkie, Fiona; Moore, Karen

2013-03-01

To examine the extent that novel cigarette pack shapes and openings have on smokers' perceptions of those packs and the cigarettes contained within. Using a web-based survey, 160 young adult ever-smokers (18-29 years) were shown computer images of plain packaged cigarette packs in five different shapes. This was followed by packs illustrating five different methods of opening. Brand (prestige or budget) and size of the health warnings (30% or 70% warning size) were between-subject conditions. Respondents ranked packs on attractiveness, perceived quality of the cigarettes contained within and extent that the pack distracted from health warnings. Ratings of attractiveness and perceived quality were significantly associated in both substudies, but tendency to distract from warnings was more independent. Significant differences were found between the pack shapes on attractiveness, perceived quality and distraction from warnings. Standard, 2×10 and 4×5 packs were ranked less attractive than Bevelled and Rounded packs. 2×10 and 4×5 packs were also perceived as lower quality than Bevelled and Rounded packs. The Standard pack was less distracting to health warnings than all other shapes except the 2×10 pack. Pack openings were perceived as different on quality of cigarettes contained and extent of distraction to warnings. The Standard Flip-top was rated significantly lower in distracting from warnings than all other openings. Pack shape and pack opening affect ever-smokers' perceptions of the packs and the cigarettes they contain. This means that they have the potential to create appeal and differentiate products and thus should be regulated.

Self-assessment of genital anatomy, sexual sensitivity and function in women: implications for genitoplasty.

PubMed

Schober, Justine M; Meyer-Bahlburg, Heino F L; Ransley, Philip G

2004-09-01

To assess the perceptions of healthy women of their genital anatomy and sexual sensitivity, and to provide suggestions for genitoplasty based on this information, as the success of genitoplasty has historically relied upon the surgeon's perception of the patient's anatomy and function, rather than the patient's perception of outcome in terms of appearance and erotic sensitivity. Fifty healthy, sexually active, adult women (aged 20-56 years) with no history of genital surgery completed the female version of the Self-Assessment of Genital Anatomy and Sexual Function. This self- report questionnaire comprises written text and images enabling women to rate the appearance, size and position of clitoris and vagina, as well as the intensity of orgasm and effort required for achieving orgasm in specified areas around the clitoris and within the vagina. Anatomical locations were compared for these ratings by repeated-measures analysis of variance. Anatomically, 46% of women described their clitoris as 'moderate-sized and raised', 42% as 'small and raised', and 78% reported that their vaginal opening was adequate for sexual penetration. The women reported the strongest orgasm and least effort to obtain an orgasm with stimulation of the area on and above the clitoris. For vaginal sensitivity, scores for orgasm intensity increased, and for orgasm effort decreased, with increasing vaginal depth, and they indicated less sexual sensitivity for the vagina than for the external genitalia. The skin above the clitoris, and the clitoris itself, appeared to be the most sexually sensitive. During genitoplasty, attention to preserving skin-flap integrity in this area seems appropriate.

A Longitudinal Analysis of the Influence of the Neighborhood Environment on Recreational Walking within the Neighborhood: Results from RESIDE

PubMed Central

Knuiman, Matthew; Divitini, Mark; Foster, Sarah; Hooper, Paula; Boruff, Bryan; Bull, Fiona; Giles-Corti, Billie

2017-01-01

Background: There is limited longitudinal evidence confirming the role of neighborhood environment attributes in encouraging people to walk more or if active people simply choose to live in activity-friendly neighborhoods. Natural experiments of policy changes to create more walkable communities provide stronger evidence for a causal effect of neighborhood environments on residents’ walking. Objectives: We aimed to investigate longitudinal associations between objective and perceived neighborhood environment measures and neighborhood recreational walking. Methods: We analyzed longitudinal data collected over 8 yr (four surveys) from the RESIDential Environments (RESIDE) Study (Perth, Australia, 2003–2012). At each time point, participants reported the frequency and total minutes of recreational walking/week within their neighborhood and neighborhood environment perceptions. Objective measures of the neighborhood environment were generated using a Geographic Information System (GIS). Results: Local recreational walking was influenced by objectively measured access to a medium-/large-size park, beach access, and higher street connectivity, which was reduced when adjusted for neighborhood perceptions. In adjusted models, positive perceptions of access to a park and beach, higher street connectivity, neighborhood esthetics, and safety from crime were independent determinants of increased neighborhood recreational walking. Local recreational walking increased by 9 min/wk (12% increase in frequency) for each additional perceived neighborhood attribute present. Conclusions: Our findings provide urban planners and policy makers with stronger causal evidence of the positive impact of well-connected neighborhoods and access to local parks of varying sizes on local residents’ recreational walking and health. https://doi.org/10.1289/EHP823 PMID:28728139

A mass-density model can account for the size-weight illusion

PubMed Central

Bergmann Tiest, Wouter M.; Drewing, Knut

2018-01-01

When judging the heaviness of two objects with equal mass, people perceive the smaller and denser of the two as being heavier. Despite the large number of theories, covering bottom-up and top-down approaches, none of them can fully account for all aspects of this size-weight illusion and thus for human heaviness perception. Here we propose a new maximum-likelihood estimation model which describes the illusion as the weighted average of two heaviness estimates with correlated noise: One estimate derived from the object’s mass, and the other from the object’s density, with estimates’ weights based on their relative reliabilities. While information about mass can directly be perceived, information about density will in some cases first have to be derived from mass and volume. However, according to our model at the crucial perceptual level, heaviness judgments will be biased by the objects’ density, not by its size. In two magnitude estimation experiments, we tested model predictions for the visual and the haptic size-weight illusion. Participants lifted objects which varied in mass and density. We additionally varied the reliability of the density estimate by varying the quality of either visual (Experiment 1) or haptic (Experiment 2) volume information. As predicted, with increasing quality of volume information, heaviness judgments were increasingly biased towards the object’s density: Objects of the same density were perceived as more similar and big objects were perceived as increasingly lighter than small (denser) objects of the same mass. This perceived difference increased with an increasing difference in density. In an additional two-alternative forced choice heaviness experiment, we replicated that the illusion strength increased with the quality of volume information (Experiment 3). Overall, the results highly corroborate our model, which seems promising as a starting point for a unifying framework for the size-weight illusion and human heaviness perception. PMID:29447183

A mass-density model can account for the size-weight illusion.

PubMed

Wolf, Christian; Bergmann Tiest, Wouter M; Drewing, Knut

2018-01-01

When judging the heaviness of two objects with equal mass, people perceive the smaller and denser of the two as being heavier. Despite the large number of theories, covering bottom-up and top-down approaches, none of them can fully account for all aspects of this size-weight illusion and thus for human heaviness perception. Here we propose a new maximum-likelihood estimation model which describes the illusion as the weighted average of two heaviness estimates with correlated noise: One estimate derived from the object's mass, and the other from the object's density, with estimates' weights based on their relative reliabilities. While information about mass can directly be perceived, information about density will in some cases first have to be derived from mass and volume. However, according to our model at the crucial perceptual level, heaviness judgments will be biased by the objects' density, not by its size. In two magnitude estimation experiments, we tested model predictions for the visual and the haptic size-weight illusion. Participants lifted objects which varied in mass and density. We additionally varied the reliability of the density estimate by varying the quality of either visual (Experiment 1) or haptic (Experiment 2) volume information. As predicted, with increasing quality of volume information, heaviness judgments were increasingly biased towards the object's density: Objects of the same density were perceived as more similar and big objects were perceived as increasingly lighter than small (denser) objects of the same mass. This perceived difference increased with an increasing difference in density. In an additional two-alternative forced choice heaviness experiment, we replicated that the illusion strength increased with the quality of volume information (Experiment 3). Overall, the results highly corroborate our model, which seems promising as a starting point for a unifying framework for the size-weight illusion and human heaviness perception.

A one-size-fits-all HIV prevention and education approach?: Analyzing and interpreting divergent HIV risk perceptions between African American and East African immigrant women in Washington, DC

PubMed Central

De Jesus, Maria; Taylor, Juanita; Maine, Cathleen; Nalls, Patricia

2015-01-01

Background To date, there are very few comparative US studies and none in DC that distinguish between US-born and foreign-born Black women to examine and compare their perceptions of HIV risk. This qualitative study, therefore, analyzes African American and East African women’s perceptions of HIV risk in the Washington DC Metropolitan area, which has the highest AIDS rate in the US. Methods Forty in-depth, semi-structured interviews and 10 cognitive interviews were conducted among a sample of 25 African American women and 25 East African born women between October 2012 and March 2013 to examine perceptions regarding HIV risk. The in-depth semi-structured interviews were preceded by the cognitive interviews and accompanying survey. Study protocol was reviewed and approved by the American University Institutional Review Board. Results Adopting Boerma and Weir’s Proximate Determinants conceptual framework to interpret the data, the results of the study demonstrate that African American and East African immigrant women have divergent perceptions of HIV risk. While African American women ascribe HIV risk to individual-level behaviors and choices such as unprotected sex, East African women attribute HIV risk to conditions of poverty and survival. Conclusions Study findings suggest that addressing HIV prevention and education among Black women in DC will require distinct and targeted strategies that are culturally and community-centered in order to resonate with these different audiences. PMID:26766523

A One-Size-Fits-All HIV Prevention and Education Approach?: Interpreting Divergent HIV Risk Perceptions Between African American and East African Immigrant Women in Washington, DC Using the Proximate-Determinants Conceptual Framework.

PubMed

De Jesus, Maria; Taylor, Juanita; Maine, Cathleen; Nalls, Patricia

2016-02-01

To date, there are very few comparative US studies and none in DC that distinguish between US-born and foreign-born black women to examine and compare their perceptions of HIV risk. This qualitative study, therefore, analyzes African American and East African women's perceptions of HIV risk in the Washington DC Metropolitan area, which has the highest AIDS rate in the United States. Forty in-depth, semistructured interviews and 10 cognitive interviews were conducted among a sample of 25 African American women and 25 East African born women between October 2012 and March 2013 to examine perceptions regarding HIV risk. The in-depth semistructured interviews were preceded by the cognitive interviews and accompanying survey. Study protocol was reviewed and approved by the American University Institutional Review Board. Adopting Boerma and Weir's Proximate Determinants conceptual framework to interpret the data, the results of the study demonstrate that African American and East African immigrant women have divergent perceptions of HIV risk. Although African American women ascribe HIV risk to individual-level behaviors and choices such as unprotected sex, East African women attribute HIV risk to conditions of poverty and survival. Study findings suggest that addressing HIV prevention and education among black women in DC will require distinct and targeted strategies that are culturally and community-centered to resonate with these different audiences.

Attentional Bias Modification for Social Anxiety Disorder: What do Patients Think and Why does it Matter?

PubMed

Kuckertz, Jennie M; Schofield, Casey A; Clerkin, Elise M; Primack, Jennifer; Boettcher, Hannah; Weisberg, Risa B; Amir, Nader; Beard, Courtney

2018-05-06

In the past decade, a great deal of research has examined the efficacy and mechanisms of attentional bias modification (ABM), a computerized cognitive training intervention for anxiety and other disorders. However, little research has examined how anxious patients perceive ABM, and it is unclear to what extent perceptions of ABM influence outcome. To examine patient perceptions of ABM across two studies, using a mixed methods approach. In the first study, participants completed a traditional ABM program and received a hand-out with minimal information about the purpose of the task. In the second study, participants completed an adaptive ABM program and were provided with more extensive rationale and instructions for changing attentional biases. A number of themes emerged from qualitative data related to perceived symptom changes and mechanisms of action, acceptability, early perceptions of the program, barriers/facilitators to engagement, and responses to adaptive features. Moreover, quantitative data suggested that patients' perceptions of the program predicted symptom reduction as well as change in attentional bias. Our quantitative data suggest that it may be possible to quickly and inexpensively identify some patients who may benefit from current ABM programs, although our qualitative data suggest that ABM needs major modifications before it will be an acceptable and credible treatment more broadly. Although the current study was limited by sample size and design features of the parent trials from which these data originated, our findings may be useful for guiding hypotheses in future studies examining patient perceptions towards ABM.

Dental Hygiene Students' Perceptions of Importance and Confidence in Applying Motivational Interviewing During Patient Care.

PubMed

Mills, Angela; Kerschbaum, Wendy E; Richards, Philip S; Czarnecki, Gail A; Kinney, Janet S; Gwozdek, Anne E

2017-02-01

Purpose: Motivational Interviewing (MI) is an evidence-based, patient-centered counseling approach for eliciting behavior change. In 2012, the University of Michigan (U-M) Dental Hygiene Program significantly enhanced their behavior change curriculum by reinforcing and building upon the Motivational Interviewing segment. The purpose of this study was to examine students' perceptions of the importance of MI and their confidence in applying it during patient care. Methods: A convenience sample of 22 U-M Class of 2015 dental hygiene students who had received an enhanced curriculum participated in this study, utilizing a retrospective, pre-test/post-test design. Results: A Wilcoxon signed rank test was used to compare the differences in average ranks between T1 (Retrospective Pre-Test) and T4 (Post-Test 3) for the importance and confidence questions at each time point for the Class of 2015. Students' perceptions of importance increased with statistical significance in five out of eight MI strategies. Perceptions in confidence increased in seven out of eight strategies. Effect size ranged from .00 to .55. Assessment of qualitative data provided additional insight on student experiences. Conclusion: Student perceptions of importance of using MI and their confidence in applying MI increased in a majority of the strategy categories. Successes with patient health behavior change and challenges with time to integrate this in practice were noted. Research on the longitudinal impact and faculty feedback calibration is recommended. Copyright © 2017 The American Dental Hygienists’ Association.

Modeling visual clutter perception using proto-object segmentation

PubMed Central

Yu, Chen-Ping; Samaras, Dimitris; Zelinsky, Gregory J.

2014-01-01

We introduce the proto-object model of visual clutter perception. This unsupervised model segments an image into superpixels, then merges neighboring superpixels that share a common color cluster to obtain proto-objects—defined here as spatially extended regions of coherent features. Clutter is estimated by simply counting the number of proto-objects. We tested this model using 90 images of realistic scenes that were ranked by observers from least to most cluttered. Comparing this behaviorally obtained ranking to a ranking based on the model clutter estimates, we found a significant correlation between the two (Spearman's ρ = 0.814, p < 0.001). We also found that the proto-object model was highly robust to changes in its parameters and was generalizable to unseen images. We compared the proto-object model to six other models of clutter perception and demonstrated that it outperformed each, in some cases dramatically. Importantly, we also showed that the proto-object model was a better predictor of clutter perception than an actual count of the number of objects in the scenes, suggesting that the set size of a scene may be better described by proto-objects than objects. We conclude that the success of the proto-object model is due in part to its use of an intermediate level of visual representation—one between features and objects—and that this is evidence for the potential importance of a proto-object representation in many common visual percepts and tasks. PMID:24904121

Illness perception and fibromyalgia impact on female patients from Spain and the Netherlands: do cultural differences exist?

PubMed

Ruiz-Montero, Pedro J; Van Wilgen, C Paul; Segura-Jiménez, Victor; Carbonell-Baeza, Ana; Delgado-Fernández, Manuel

2015-12-01

The purpose of this study was to examine the differences in illness perception and overall impact on fibromyalgia females from Spain and the Netherlands. A total of 325 fibromyalgia females from Spain (54.3 ± 7.1 years) and the Netherlands (51.8 ± 7.2 years) participated in the study. Illness perception and impact of fibromyalgia were assessed by the Revised Illness Perception Questionnaire and the Fibromyalgia Impact Questionnaire, respectively. Spanish fibromyalgia females perceived more symptoms related to their fibromyalgia (identity) such as nausea, breathlessness, wheezing or fatigue (P < 0.001) and had greater emotional representation (P < 0.01). Dutch fibromyalgia females experienced less timeline (acute/chronic) and consequences (all, P < 0.05), had a better cyclical timeline, personal control, treatment control and illness coherence (all, P < 0.001). Spanish fibromyalgia females reported higher impact of fibromyalgia than Dutch females (61.2 + 14.8 vs. 54.9 + 16.4, respectively; P < 0.001), but the effect size was small (Cohen's d = 0.41) . Impact of fibromyalgia and negative views of fibromyalgia were higher in Spanish fibromyalgia females, whereas Dutch fibromyalgia females presented higher score of positive beliefs about the controllability of the illness. Psychological interventions which help patients to cope with their illness perception might lead to an improvement of the impact of the disease on fibromyalgia females.

Internet video telephony allows speech reading by deaf individuals and improves speech perception by cochlear implant users.

PubMed

Mantokoudis, Georgios; Dähler, Claudia; Dubach, Patrick; Kompis, Martin; Caversaccio, Marco D; Senn, Pascal

2013-01-01

To analyze speech reading through Internet video calls by profoundly hearing-impaired individuals and cochlear implant (CI) users. Speech reading skills of 14 deaf adults and 21 CI users were assessed using the Hochmair Schulz Moser (HSM) sentence test. We presented video simulations using different video resolutions (1280 × 720, 640 × 480, 320 × 240, 160 × 120 px), frame rates (30, 20, 10, 7, 5 frames per second (fps)), speech velocities (three different speakers), webcameras (Logitech Pro9000, C600 and C500) and image/sound delays (0-500 ms). All video simulations were presented with and without sound and in two screen sizes. Additionally, scores for live Skype™ video connection and live face-to-face communication were assessed. Higher frame rate (>7 fps), higher camera resolution (>640 × 480 px) and shorter picture/sound delay (<100 ms) were associated with increased speech perception scores. Scores were strongly dependent on the speaker but were not influenced by physical properties of the camera optics or the full screen mode. There is a significant median gain of +8.5%pts (p = 0.009) in speech perception for all 21 CI-users if visual cues are additionally shown. CI users with poor open set speech perception scores (n = 11) showed the greatest benefit under combined audio-visual presentation (median speech perception +11.8%pts, p = 0.032). Webcameras have the potential to improve telecommunication of hearing-impaired individuals.

Which is the Ideal Breast Size?: Some Social Clues for Plastic Surgeons.

PubMed

Raposio, Edoardo; Belgrano, Valerio; Santi, PierLuigi; Chiorri, Carlo

2016-03-01

To provide plastic surgeons with more detailed information as to factors affecting the perception of female attractiveness, the present study was aimed to investigate whether the interaction effect of breast and body size on ratings of female attractiveness is moderated by sociodemographic variables and whether ratings of shapeliness diverge from those of attractiveness.A community sample of 958 Italian participants rated the attractiveness and the shapeliness of 15 stimuli (5 breast sizes × 3 body sizes) in which frontal, 3/4, and profile views of the head and torso of a faceless woman were jointly shown.Bigger breast sizes obtained the highest attractiveness ratings, but the breast-by-body size interaction was also significant. Evidence was found of a moderator role of sex, marital status, and age. When the effects of breast and body size and their interaction had been ruled out, sex differences were at best very slight and limited to very specific combinations of breast and body sizes. Ratings of attractiveness and shapeliness were highly correlated and did not significantly differ.Results suggest that to address women's psychological needs, concerns, and expectations about their appearance, plastic surgeons should not simply focus on breast size but should carefully consider the 'big picture': the body in its entirety.

Explaining Comfort with Homosexuality among Social Work Students: The Impact of Demographic, Contextual, and Attitudinal Factors

ERIC Educational Resources Information Center

Swank, Eric; Raiz, Lisa

2007-01-01

While recent research explores the determinants of homophobia among college students, only a few studies look at the perceptions of homosexuals among social work students. Unfortunately these rare studies generally present a modest list of predictor variables or small sample sizes. To address this gap, this research explores the ways in which…

Cultural Differences in Face-ism: Male Politicians Have Bigger Heads in More Gender-Equal Cultures

ERIC Educational Resources Information Center

Konrath, Sara; Au, Josephine; Ramsey, Laura R.

2012-01-01

Women are visually depicted with lower facial prominence than men, with consequences for perceptions of their competence. The current study examines the relationship between the size of this "face-ism" bias (i.e., individual or micro-level sexism) and a number of gender inequality indicators (i.e., institutional or macro-level sexism) at the…

The Significance of Event Information for 6- to 16-Month-Old Infants' Perception of Containment

ERIC Educational Resources Information Center

Smitsman, Ad W.; Dejonckheere, Peter J. N.; De Wit, Tessa C. J.

2009-01-01

Four experiments familiarized 6-, 9-, 12-, and 16-month-old infants to a solid block that was repeatedly lowered into a semitransparent container. In test trials the end state, containment, was either compatible or incompatible with the objects' size and position. In Experiment 1, infants saw the block and box successively before they observed the…

Adolescent Psychological and Academic Adjustment as a Function of Discrepancies between Actual and Ideal Self-Perceptions

ERIC Educational Resources Information Center

Ferguson, Gail M.; Hafen, Christopher A.; Laursen, Brett

2010-01-01

Actual-ideal discrepancies are associated with adolescent emotional distress and there is evidence that the size of discrepancies matters. However, the direction of discrepancies has not been examined, perhaps due to limitations of widely used self-discrepancy measures. Two hundred and twelve 7th, 9th and 11th grade students (59% female) in a…

Visual Coding of Human Bodies: Perceptual Aftereffects Reveal Norm-Based, Opponent Coding of Body Identity

ERIC Educational Resources Information Center

Rhodes, Gillian; Jeffery, Linda; Boeing, Alexandra; Calder, Andrew J.

2013-01-01

Despite the discovery of body-selective neural areas in occipitotemporal cortex, little is known about how bodies are visually coded. We used perceptual adaptation to determine how body identity is coded. Brief exposure to a body (e.g., anti-Rose) biased perception toward an identity with opposite properties (Rose). Moreover, the size of this…

To Slideware or Not to Slideware: Students' Experiences with PowerPoint vs. Lecture

ERIC Educational Resources Information Center

Amare, Nicole

2006-01-01

This study analyzes the performance and attitudes of technical writing students in PowerPoint-enhanced and in non-PowerPoint lectures. Four classes of upper-level undergraduates (n = 84) at a mid-sized, Southern university taking a one-semester technical writing course were surveyed at the beginning and end of the course about their perceptions of…

The Social Construction of Social Facts: Using the U.S. Census to Examine Race as a Scientific and Moral Category

ERIC Educational Resources Information Center

Townsley, Eleanor

2007-01-01

This article describes an exercise that explores how race categories and classifications are socially constructed scientifically. In an introductory sociology setting, students compare their perceptions of the size of minority populations with counts from the U.S. Census. In a series of debriefing sessions, students analyze both their perceptions…

Theory of mind and perceptual context-processing in schizophrenia.

PubMed

Uhlhaas, Peter J; Phillips, William A; Schenkel, Lindsay S; Silverstein, Steven M

2006-07-01

A series of studies have suggested that schizophrenia patients are deficient in theory of mind (ToM). However, the cognitive mechanisms underlying ToM deficits in schizophrenia are largely unknown. The present study examined the hypothesis that impaired ToM in schizophrenia can be understood as a deficit in context processing. Disorganised schizophrenia patients (N = 12), nondisorganised schizophrenia patients (N = 36), and nonpsychotic psychiatric patients (N = 26) were tested on three ToM tasks and a visual size perception task, a measure of perceptual context processing. In addition, statistical analyses were carried out which compared chronic, treatment-refractory schizophrenia patients (N = 28) to those with an episodic course of illness (N = 20). Overall, ToM performance was linked to deficits in context processing in schizophrenia patients. Statistical comparisons showed that disorganised as well as chronic schizophrenia patients were more impaired in ToM but more accurate in a visual size perception task where perceptual context is misleading. This pattern of results is interpreted as indicating a possible link between deficits in ToM and perceptual context processing, which together with deficits in perceptual grouping, are part of a broader dysfunction in cognitive coordination in schizophrenia.

Exploring managers' views on span of control: more than a headcount.

PubMed

Wong, Carol A; Elliott-Miller, Pat; Laschinger, Heather; Cuddihy, Michael; Meyer, Raquel M; Keatings, Margaret; Burnett, Camille; Szudy, Natalie

2014-03-01

The purpose of this qualitative study was to explore front-line managers' (FLMs') perceptions of their span of control (SOC) and how they manage it. As part of a larger quantitative study examining relationships between FLMs' SOC and performance outcomes, 10 manager focus groups were conducted by teleconference, involving 48 managers from 14 academic healthcare organizations. Themes and subthemes were identified according to (a) perceptions of the size and scope of SOC; (b) factors influencing the complexity of SOC; (c) supports needed to manage SOC; (d) changing leadership style; and (e) ways of coping with role overload. Participants described system demands as a significant contributor to their work responsibilities and a sense of role overload. About half of managers stated their SOC was unreasonable and that they lacked the necessary supports to manage it. Many managers who described their SOC as reasonable still expressed concerns about internal and external workload pressures that contributed to changing leadership style and role overload. Findings reinforce the importance of organizational strategies to create regular dialogue with FLMs regarding the size, complexity and appropriateness of current spans and to provide the resource supports necessary to ensure they can manage their SOC effectively.

The Relationship between Vehicle Weight/Size and Safety

NASA Astrophysics Data System (ADS)

Wenzel, Tom; Ross, Marc

2008-09-01

Light-duty vehicles account for about 20% of US CO2 emissions. However, new vehicle fuel economy standards have not been significantly tightened since they were first enacted three decades ago. A historical impediment to imposing tougher fuel economy standards has been the long-standing perception that reducing the mass of a car or truck would make it more dangerous to its occupants in a crash. One often hears that this perception is dictated by "simple physics:" that, all else being equal, you are at greater risk in a lighter vehicle than in a heavier one. Our research on driver fatality risk has found that, when it comes to vehicle safety, all else is never equal. Vehicle mass is not the most important variable in determining occupant safety, not even in frontal crashes between two vehicles. You are at no greater risk driving an average car than you are driving a much heavier (and less fuel efficient) truck-based SUV. And larger and heavier truck-based SUVs and pickups impose enormous risks on car occupants. We summarize the most recent research on the interplay between vehicle weight, size and safety, and what the implications are for new state and federal standards to reduce vehicle CO2 emissions.

Population survey and management strategies of free-roaming dogs (Canis familiaris) on Saipan, Commonwealth of the Northern Mariana Islands.

PubMed

Nimer, Adrianna; Meneses, Nashelly; Watson, Zachary D; Shuster, Stephen M; Benford, Russell

2018-01-01

The island of Saipan, Commonwealth of the Northern Mariana Islands, is populated by free-roaming dogs who were introduced during World War II. The local nonhuman animal control agency manages this population; however, the demographic information and public perception of this population remain unknown. To characterize the free-roaming dog population, an island-wide survey on Saipan was conducted. Photographic, mark-recapture data were used to estimate the population size per land type. Age, sex, sociality, and behavior per land type were documented and associations between these variables were tested using G tests. The effects of land type and urbanization on dog abundance were also analyzed. Lastly, in-person surveys provided data on the public perception of free-roaming dogs. Four main findings are reported: (a) The population size of free-roaming dogs on Saipan is estimated at 21,316. (b) Most dogs encountered were sentry adults. (c) Dog abundance increased with urbanization level and was highest in urban areas. (d) The public perceived free-roaming dogs as a health concern and suggested the implementation of leash laws and sheltering initiatives. This article discusses potential and existing population management strategies for free-roaming dogs on Saipan.

Measuring pictorial balance perception at first glance using Japanese calligraphy

PubMed Central

Gershoni, Sharon; Hochstein, Shaul

2011-01-01

According to art theory, pictorial balance acts to unify picture elements into a cohesive composition. For asymmetrical compositions, balancing elements is thought to be similar to balancing mechanical weights in a framework of symmetry axes. Assessment of preference for balance (APB), based on the symmetry-axes framework suggested in Arnheim R, 1974 Art and Visual Perception: A Psychology of the Creative Eye (Berkeley, CA: University of California Press), successfully matched subject balance ratings of images of geometrical shapes over unlimited viewing time. We now examine pictorial balance perception of Japanese calligraphy during first fixation, isolated from later cognitive processes, comparing APB measures with results from balance-rating and comparison tasks. Results show high between-task correlation, but low correlation with APB. We repeated the rating task, expanding the image set to include five rotations of each image, comparing balance perception of artist and novice participant groups. Rotation has no effect on APB balance computation but dramatically affects balance rating, especially for art experts. We analyze the variety of rotation effects and suggest that, rather than depending on element size and position relative to symmetry axes, first fixation balance processing derives from global processes such as grouping of lines and shapes, object recognition, preference for horizontal and vertical elements, closure, and completion, enhanced by vertical symmetry. PMID:23145242

Is This Stalking? Perceptions of Stalking Behavior Among Young Male and Female Adults in Hong Kong and Mainland China.

PubMed

Chan, Heng Choon Oliver; Sheridan, Lorraine

2017-05-01

Most studies of stalking are conducted with samples from individualist cultures. Little is known about the phenomenon within collectivist cultures. The present study is arguably the first stalking study conducted in Hong Kong. Specifically, this study investigates a large sample of Asian college students' ( N = 2,496) perceptions of stalking behavior, potential reasons for stalking, and coping strategies that may be employed by stalking victims. Associations between these variables and gender and culture (Hong Kong vs. Mainland China) were also explored. Gender was more strongly associated with perceptions of stalking behavior than was culture. Gender was less strongly associated with perceptions concerning motivations for stalking and the effectiveness of coping strategies that may be employed by stalking victims than was culture. Effect sizes for all associations with culture were small, perhaps due to a high degree of similarity between the two cultures examined. The findings are generally supportive of similar results produced by previous work conducted within individualistic Western cultures, suggesting that stalking and the way that it is perceived may be universal in nature. This study concludes with the argument that legislation against stalking needs to be extended to non-Western countries, such as Hong Kong and Mainland China, as antistalking laws are relatively scarce outside Western industrialized countries.

Morphological characteristics, anatomical structure, and gene expression: novel insights into gibberellin biosynthesis and perception during carrot growth and development

PubMed Central

Wang, Guang-Long; Xiong, Fei; Que, Feng; Xu, Zhi-Sheng; Wang, Feng; Xiong, Ai-Sheng

2015-01-01

Gibberellins (GAs) are considered potentially important regulators of cell elongation and expansion in plants. Carrot undergoes significant alteration in organ size during its growth and development. However, the molecular mechanisms underlying gibberellin accumulation and perception during carrot growth and development remain unclear. In this study, five stages of carrot growth and development were investigated using morphological and anatomical structural techniques. Gibberellin levels in leaf, petiole, and taproot tissues were also investigated for all five stages. Gibberellin levels in the roots initially increased and then decreased, but these levels were lower than those in the petioles and leaves. Genes involved in gibberellin biosynthesis and signaling were identified from the carrotDB, and their expression was analyzed. All of the genes were evidently responsive to carrot growth and development, and some of them showed tissue-specific expression. The results suggested that gibberellin level may play a vital role in carrot elongation and expansion. The relative transcription levels of gibberellin pathway-related genes may be the main cause of the different bioactive GAs levels, thus exerting influences on gibberellin perception and signals. Carrot growth and development may be regulated by modification of the genes involved in gibberellin biosynthesis, catabolism, and perception. PMID:26504574

Morphological characteristics, anatomical structure, and gene expression: novel insights into gibberellin biosynthesis and perception during carrot growth and development.

PubMed

Wang, Guang-Long; Xiong, Fei; Que, Feng; Xu, Zhi-Sheng; Wang, Feng; Xiong, Ai-Sheng

2015-01-01

Gibberellins (GAs) are considered potentially important regulators of cell elongation and expansion in plants. Carrot undergoes significant alteration in organ size during its growth and development. However, the molecular mechanisms underlying gibberellin accumulation and perception during carrot growth and development remain unclear. In this study, five stages of carrot growth and development were investigated using morphological and anatomical structural techniques. Gibberellin levels in leaf, petiole, and taproot tissues were also investigated for all five stages. Gibberellin levels in the roots initially increased and then decreased, but these levels were lower than those in the petioles and leaves. Genes involved in gibberellin biosynthesis and signaling were identified from the carrotDB, and their expression was analyzed. All of the genes were evidently responsive to carrot growth and development, and some of them showed tissue-specific expression. The results suggested that gibberellin level may play a vital role in carrot elongation and expansion. The relative transcription levels of gibberellin pathway-related genes may be the main cause of the different bioactive GAs levels, thus exerting influences on gibberellin perception and signals. Carrot growth and development may be regulated by modification of the genes involved in gibberellin biosynthesis, catabolism, and perception.

Mutations in the Heme Exporter FLVCR1 Cause Sensory Neurodegeneration with Loss of Pain Perception.

PubMed

Chiabrando, Deborah; Castori, Marco; di Rocco, Maja; Ungelenk, Martin; Gießelmann, Sebastian; Di Capua, Matteo; Madeo, Annalisa; Grammatico, Paola; Bartsch, Sophie; Hübner, Christian A; Altruda, Fiorella; Silengo, Lorenzo; Tolosano, Emanuela; Kurth, Ingo

2016-12-01

Pain is necessary to alert us to actual or potential tissue damage. Specialized nerve cells in the body periphery, so called nociceptors, are fundamental to mediate pain perception and humans without pain perception are at permanent risk for injuries, burns and mutilations. Pain insensitivity can be caused by sensory neurodegeneration which is a hallmark of hereditary sensory and autonomic neuropathies (HSANs). Although mutations in several genes were previously associated with sensory neurodegeneration, the etiology of many cases remains unknown. Using next generation sequencing in patients with congenital loss of pain perception, we here identify bi-allelic mutations in the FLVCR1 (Feline Leukemia Virus subgroup C Receptor 1) gene, which encodes a broadly expressed heme exporter. Different FLVCR1 isoforms control the size of the cytosolic heme pool required to sustain metabolic activity of different cell types. Mutations in FLVCR1 have previously been linked to vision impairment and posterior column ataxia in humans, but not to HSAN. Using fibroblasts and lymphoblastoid cell lines from patients with sensory neurodegeneration, we here show that the FLVCR1-mutations reduce heme export activity, enhance oxidative stress and increase sensitivity to programmed cell death. Our data link heme metabolism to sensory neuron maintenance and suggest that intracellular heme overload causes early-onset degeneration of pain-sensing neurons in humans.

Perceptions of family planning among low-income men in Western Kenya.

PubMed

Wambui, T; Ek, A-C; Alehagen, S

2009-09-01

Men have rarely been involved in either receiving or providing information on sexuality, reproductive health or birth spacing. They have also been ignored or excluded in one way or the other from participating in many family planning programmes as family planning is viewed as a woman's affair. To describe the perceptions of family planning among low-income men in Western Kenya. A qualitative study using focus group interviews and content analysis was conducted, with 64 men aged 15-54 years participating actively. Perceptions of family planning were manifold. For example, some perceived it as meaning having the number of children one is able to provide for. Most men knew about traditional and modern methods of birth control, although their knowledge was poor and misconceived. Modern methods were thought to give side effects, discouraging family planning. Low instances of family planning were also because of the fact that culturally, children are considered wealth. A law advocating family size limitation was regarded as necessary for the future. Men's perceptions of family planning are manifold. Their knowledge about contraception is poor and sometimes misconceived. Preferences regarding a child's gender are strong, thus attitudes and cultural beliefs that might hinder family planning have to be considered. A policy on male contraception and contraceptive services is seen as necessary.

Knowledge, Perceptions, and Self-reported Performance of Hand Hygiene Among Registered Nurses at Community-based Hospitals in the Republic of Korea: A Cross-sectional Multi-center Study.

PubMed

Oh, Hyang Soon

2018-05-01

To assess the nurses' hand hygiene (HH) knowledge, perception, attitude, and self-reported performance in small- and medium-sized hospitals after Middle East Respiratory Syndrome outbreak. The structured questionnaire was adapted from the World Health Organization's survey. Data were collected between June 26 and July 14, 2017. Nurses showed scores on knowledge (17.6±2.5), perception (69.3±0.8), self-reported HH performance of non-self (86.0±11.0), self-reported performance of self (88.2±11.0), and attitude (50.5±5.5). HH performance rate of non-self was Y 1 =36.678+ 0.555X1 (HH performance rate of self) (adjusted R 2 =0.280, p <0.001). The regression model for performance was Y 4 =18.302+0.247 X 41 (peception)+0.232 X 42 (attitude)+0.875 X 42 (role model); coefficients were significant statistically except attitude, and this model significant statistically (adjusted R 2 =0.191, p <0.001). Advanced HH education program would be developed and operated continuously. Perception, attitude, role model was found to be a significant predictors of HH performance of self. So these findings could be used in future HH promotion strategies for nurses.

Default perception of high-speed motion

PubMed Central

Wexler, Mark; Glennerster, Andrew; Cavanagh, Patrick; Ito, Hiroyuki; Seno, Takeharu

2013-01-01

When human observers are exposed to even slight motion signals followed by brief visual transients—stimuli containing no detectable coherent motion signals—they perceive large and salient illusory jumps. This visually striking effect, which we call “high phi,” challenges well-entrenched assumptions about the perception of motion, namely the minimal-motion principle and the breakdown of coherent motion perception with steps above an upper limit called dmax. Our experiments with transients, such as texture randomization or contrast reversal, show that the magnitude of the jump depends on spatial frequency and transient duration—but not on the speed of the inducing motion signals—and the direction of the jump depends on the duration of the inducer. Jump magnitude is robust across jump directions and different types of transient. In addition, when a texture is actually displaced by a large step beyond the upper step size limit of dmax, a breakdown of coherent motion perception is expected; however, in the presence of an inducer, observers again perceive coherent displacements at or just above dmax. In summary, across a large variety of stimuli, we find that when incoherent motion noise is preceded by a small bias, instead of perceiving little or no motion—as suggested by the minimal-motion principle—observers perceive jumps whose amplitude closely follows their own dmax limits. PMID:23572578

Melodic interval perception by normal-hearing listeners and cochlear implant users

PubMed Central

Luo, Xin; Masterson, Megan E.; Wu, Ching-Chih

2014-01-01

The perception of melodic intervals (sequential pitch differences) is essential to music perception. This study tested melodic interval perception in normal-hearing (NH) listeners and cochlear implant (CI) users. Melodic interval ranking was tested using an adaptive procedure. CI users had slightly higher interval ranking thresholds than NH listeners. Both groups' interval ranking thresholds, although not affected by root note, significantly increased with standard interval size and were higher for descending intervals than for ascending intervals. The pitch direction effect may be due to a procedural artifact or a difference in central processing. In another test, familiar melodies were played with all the intervals scaled by a single factor. Subjects rated how in tune the melodies were and adjusted the scaling factor until the melodies sounded the most in tune. CI users had lower final interval ratings and less change in interval rating as a function of scaling factor than NH listeners. For CI users, the root-mean-square error of the final scaling factors and the width of the interval rating function were significantly correlated with the average ranking threshold for ascending rather than descending intervals, suggesting that CI users may have focused on ascending intervals when rating and adjusting the melodies. PMID:25324084

Perception of Air Pollution in the Jinchuan Mining Area, China: A Structural Equation Modeling Approach

PubMed Central

Li, Zhengtao; Folmer, Henk; Xue, Jianhong

2016-01-01

Studies on the perception of air pollution in China are very limited. The aim of this paper is to help to fill this gap by analyzing a cross-sectional dataset of 759 residents of the Jinchuan mining area, Gansu Province, China. The estimations suggest that perception of air pollution is two-dimensional. The first dimension is the perceived intensity of air pollution and the second is the perceived hazardousness of the pollutants. Both dimensions are influenced by environmental knowledge. Perceived intensity is furthermore influenced by socio-economic status and proximity to the pollution source; perceived hazardousness is influenced by socio-economic status, family health experience, family size and proximity to the pollution source. There are no reverse effects from perception on environmental knowledge. The main conclusion is that virtually all Jinchuan residents perceive high intensity and hazardousness of air pollution despite the fact that public information on air pollution and its health impacts is classified to a great extent. It is suggested that, to assist the residents to take appropriate preventive action, the local government should develop counseling and educational campaigns and institutionalize disclosure of air quality conditions. These programs should pay special attention to young residents who have limited knowledge of air pollution in the Jinchuan mining area. PMID:27455291

Haptic exploration of fingertip-sized geometric features using a multimodal tactile sensor

NASA Astrophysics Data System (ADS)

Ponce Wong, Ruben D.; Hellman, Randall B.; Santos, Veronica J.

2014-06-01

Haptic perception remains a grand challenge for artificial hands. Dexterous manipulators could be enhanced by "haptic intelligence" that enables identification of objects and their features via touch alone. Haptic perception of local shape would be useful when vision is obstructed or when proprioceptive feedback is inadequate, as observed in this study. In this work, a robot hand outfitted with a deformable, bladder-type, multimodal tactile sensor was used to replay four human-inspired haptic "exploratory procedures" on fingertip-sized geometric features. The geometric features varied by type (bump, pit), curvature (planar, conical, spherical), and footprint dimension (1.25 - 20 mm). Tactile signals generated by active fingertip motions were used to extract key parameters for use as inputs to supervised learning models. A support vector classifier estimated order of curvature while support vector regression models estimated footprint dimension once curvature had been estimated. A distal-proximal stroke (along the long axis of the finger) enabled estimation of order of curvature with an accuracy of 97%. Best-performing, curvature-specific, support vector regression models yielded R2 values of at least 0.95. While a radial-ulnar stroke (along the short axis of the finger) was most helpful for estimating feature type and size for planar features, a rolling motion was most helpful for conical and spherical features. The ability to haptically perceive local shape could be used to advance robot autonomy and provide haptic feedback to human teleoperators of devices ranging from bomb defusal robots to neuroprostheses.

Do you see what I see? A comparative investigation of the Delboeuf illusion in humans (Homo sapiens), rhesus monkeys (Macaca mulatta), and capuchin monkeys (Cebus apella).

PubMed

Parrish, Audrey E; Brosnan, Sarah F; Beran, Michael J

2015-10-01

Studying visual illusions is critical to understanding typical visual perception. We investigated whether rhesus monkeys (Macaca mulatta) and capuchin monkeys (Cebus apella) perceived the Delboeuf illusion in a similar manner as human adults (Homo sapiens). To test this, in Experiment 1, we presented monkeys and humans with a relative discrimination task that required subjects to choose the larger of 2 central dots that were sometimes encircled by concentric rings. As predicted, humans demonstrated evidence of the Delboeuf illusion, overestimating central dots when small rings surrounded them and underestimating the size of central dots when large rings surrounded them. However, monkeys did not show evidence of the illusion. To rule out an alternate explanation, in Experiment 2, we presented all species with an absolute classification task that required them to classify a central dot as "small" or "large." We presented a range of ring sizes to determine whether the Delboeuf illusion would occur for any dot-to-ring ratios. Here, we found evidence of the Delboeuf illusion in all 3 species. Humans and monkeys underestimated central dot size to a progressively greater degree with progressively larger rings. The Delboeuf illusion now has been extended to include capuchin monkeys and rhesus monkeys, and through such comparative investigations we can better evaluate hypotheses regarding illusion perception among nonhuman animals. (c) 2015 APA, all rights reserved).

Phonemes: Lexical access and beyond.

PubMed

Kazanina, Nina; Bowers, Jeffrey S; Idsardi, William

2018-04-01

Phonemes play a central role in traditional theories as units of speech perception and access codes to lexical representations. Phonemes have two essential properties: they are 'segment-sized' (the size of a consonant or vowel) and abstract (a single phoneme may be have different acoustic realisations). Nevertheless, there is a long history of challenging the phoneme hypothesis, with some theorists arguing for differently sized phonological units (e.g. features or syllables) and others rejecting abstract codes in favour of representations that encode detailed acoustic properties of the stimulus. The phoneme hypothesis is the minority view today. We defend the phoneme hypothesis in two complementary ways. First, we show that rejection of phonemes is based on a flawed interpretation of empirical findings. For example, it is commonly argued that the failure to find acoustic invariances for phonemes rules out phonemes. However, the lack of invariance is only a problem on the assumption that speech perception is a bottom-up process. If learned sublexical codes are modified by top-down constraints (which they are), then this argument loses all force. Second, we provide strong positive evidence for phonemes on the basis of linguistic data. Almost all findings that are taken (incorrectly) as evidence against phonemes are based on psycholinguistic studies of single words. However, phonemes were first introduced in linguistics, and the best evidence for phonemes comes from linguistic analyses of complex word forms and sentences. In short, the rejection of phonemes is based on a false analysis and a too-narrow consideration of the relevant data.

Does wine glass size influence sales for on-site consumption? A multiple treatment reversal design.

PubMed

Pechey, Rachel; Couturier, Dominique-Laurent; Hollands, Gareth J; Mantzari, Eleni; Munafò, Marcus R; Marteau, Theresa M

2016-06-07

Wine glass size can influence both perceptions of portion size and the amount poured, but its impact upon purchasing and consumption is unknown. This study aimed to examine the impact of wine glass size on wine sales for on-site consumption, keeping portion size constant. In one establishment (with separate bar and restaurant areas) in Cambridge, England, wine glass size (Standard; Larger; Smaller) was changed over eight fortnightly periods. The bar and restaurant differ in wine sales by the glass vs. by the bottle (93 % vs. 63 % by the glass respectively). Daily wine volume purchased was 9.4 % (95 % CI: 1.9, 17.5) higher when sold in larger compared to standard-sized glasses. This effect seemed principally driven by sales in the bar area (bar: 14.4 % [3.3, 26.7]; restaurant: 8.2 % [-2.5, 20.1]). Findings were inconclusive as to whether sales were different with smaller vs. standard-sized glasses. The size of glasses in which wine is sold, keeping the portion size constant, can affect consumption, with larger glasses increasing consumption. The hypothesised mechanisms for these differential effects need to be tested in a replication study. If replicated, policy implications could include considering glass size amongst alcohol licensing requirements. ISRCTN registry: ISRCTN12018175 . Registered 12(th) May 2015.

Size Fluctuations of Near Critical Nuclei and Gibbs Free Energy for Nucleation of BDA on Cu(001)

NASA Astrophysics Data System (ADS)

Schwarz, Daniel; van Gastel, Raoul; Zandvliet, Harold J. W.; Poelsema, Bene

2012-07-01

We present a low-energy electron microscopy study of nucleation and growth of BDA on Cu(001) at low supersaturation. At sufficiently high coverage, a dilute BDA phase coexists with c(8×8) crystallites. The real-time microscopic information allows a direct visualization of near-critical nuclei, determination of the supersaturation and the line tension of the crystallites, and, thus, derivation of the Gibbs free energy for nucleation. The resulting critical nucleus size nicely agrees with the measured value. Nuclei up to 4-6 times larger still decay with finite probability, urging reconsideration of the classic perception of a critical nucleus.

Size fluctuations of near critical nuclei and Gibbs free energy for nucleation of BDA on Cu(001).

PubMed

Schwarz, Daniel; van Gastel, Raoul; Zandvliet, Harold J W; Poelsema, Bene

2012-07-06

We present a low-energy electron microscopy study of nucleation and growth of BDA on Cu(001) at low supersaturation. At sufficiently high coverage, a dilute BDA phase coexists with c(8×8) crystallites. The real-time microscopic information allows a direct visualization of near-critical nuclei, determination of the supersaturation and the line tension of the crystallites, and, thus, derivation of the Gibbs free energy for nucleation. The resulting critical nucleus size nicely agrees with the measured value. Nuclei up to 4-6 times larger still decay with finite probability, urging reconsideration of the classic perception of a critical nucleus.

Long-term support and personal adjustment of adolescent and older mothers.

PubMed

Schilmoeller, G L; Baranowski, M D; Higgins, B S

1991-01-01

Adolescent and older mothers reported the size and quality of social networks and perceptions of family support at 1, 6, and 12 months postpartum. Maternal behavior, general life satisfaction, and parental satisfaction were assessed at 12 months. No significant differences were found in the size of social networks and quality of interactions within those networks, though older mothers had significantly higher scores on perceived family support than did adolescent mothers. Perceived family support and quality of interactions within the social network generally were associated positively with maternal behavior, life satisfaction, and parental satisfaction. This was true in more cases for the adolescent than for older mothers.

Resources and estuarine health: Perceptions of elected officials and recreational fishers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burger, J.; Sanchez, J.; McMahon, M.

1999-10-29

It is important to understand the perceptions of user groups regarding both the health of their estuaries and environmental problems requiring management. Recreational fishers were interviewed to determine the perceptions of one of the traditional user groups of Barnegat Bay (New Jersey), and elected officials were interviewed to determine if the people charged with making decisions about environmental issues in the bay held similar perceptions. Although relative ratings were similar, there were significant differences in perceptions of the severity of environmental problems, and for the most part, public officials thought the problems were more severe than did the fishers. Personalmore » watercraft (often called Jet Skis) were rated as the most severe problem, followed by chemical pollution, junk, over fishing, street runoff, and boat oil. Small boats, sailboats, wind surfers, and foraging birds were not considered environmental problems by either elected officials or fishermen. The disconnect between the perceptions of the recreational fishers and those of the locally elected public officials suggests that officials may be hearing from some of the more vocal people about problems, rather than from the typical fishers. Both groups felt there were decreases in some of the resources in the bay; over 50% felt the number of fish and crabs had declined, the size of fish and crabs had declined, and the number of turtles had declined. Among recreational fishers, there were almost no differences in perceptions of the severity of environmental problems or in changes in the bay. The problems that were rated the most severe were personal watercraft and over fishing by commercial fishers. Recreational fishers ranked sailboats, wind surfers, and fishing by birds as posing no problem for the bay. Most fishers felt there had been recent major changes in Barnegat Bay, with there now being fewer and smaller fish, fewer and smaller crabs, and fewer turtles. The results suggest that the views of a wide range of coastal users should be considered when making environmental health decisions.« less

Excitability of the motor system: A transcranial magnetic stimulation study on singing and speaking.

PubMed

Royal, Isabelle; Lidji, Pascale; Théoret, Hugo; Russo, Frank A; Peretz, Isabelle

2015-08-01

The perception of movements is associated with increased activity in the human motor cortex, which in turn may underlie our ability to understand actions, as it may be implicated in the recognition, understanding and imitation of actions. Here, we investigated the involvement and lateralization of the primary motor cortex (M1) in the perception of singing and speech. Transcranial magnetic stimulation (TMS) was applied independently for both hemispheres over the mouth representation of the motor cortex in healthy participants while they watched 4-s audiovisual excerpts of singers producing a 2-note ascending interval (singing condition) or 4-s audiovisual excerpts of a person explaining a proverb (speech condition). Subjects were instructed to determine whether a sung interval/written proverb, matched a written interval/proverb. During both tasks, motor evoked potentials (MEPs) were recorded from the contralateral mouth muscle (orbicularis oris) of the stimulated motor cortex compared to a control task. Moreover, to investigate the time course of motor activation, TMS pulses were randomly delivered at 7 different time points (ranging from 500 to 3500 ms after stimulus onset). Results show that stimulation of the right hemisphere had a similar effect on the MEPs for both the singing and speech perception tasks, whereas stimulation of the left hemisphere significantly differed in the speech perception task compared to the singing perception task. Furthermore, analysis of the MEPs in the singing task revealed that they decreased for small musical intervals, but increased for large musical intervals, regardless of which hemisphere was stimulated. Overall, these results suggest a dissociation between the lateralization of M1 activity for speech perception and for singing perception, and that in the latter case its activity can be modulated by musical parameters such as the size of a musical interval. Copyright © 2015 Elsevier Ltd. All rights reserved.