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Perceptual processing in autism is associated with both 'strengths' and 'weaknesses' but within a literature that varies widely in terms of the assessments used. We report data from 12 children with autism spectrum disorders (ASD) and 12 age and IQ matched neurotypical controls tested on a set of tasks using the same stimuli throughout but systematically changing in difficulty. These tasks ranged through simple detection of stimulus onset to pairwise size discrimination across two approaching targets. Children with ASD were slower than controls even in simple detection tasks, but this did not explain further group differences found in the size discrimination of approaching targets. The results are discussed in terms of impairments in speed of responding in ASD under certain conditions of visuomotor coupling, stimulus presentation and increased information processing demands. Keywords ASD * Attention switching * Perception * Target discrimination, Introduction The perceptual abilities of children with autism spectrum disorders (ASD) are variously noted for their strengths (Frith 2003; Gonzalezet al. 2013; Happe and Frith 2010), similarities with neurotypical populations [...]

Dear Editor, The excessive rates of high-risk drinking in college students and the associated problems are well documented (ACHA, 2011; Wechsler & Nelson, 2008). Estimates suggest that approximately 40% of [...]

The aim of this study was to examine physiological, perceptual, and affective responses during self-paced walking for three age groups. 66 adult women were assigned into three groups by age: 20-25 yr. (n = 22), 30-35 yr. (n = 22), and 40-45 yr. (n = 22). Each participant completed a maximal exercise test and a 20-min. bout of walking at a self-selected pace. The preferred walking speed was similar for all age groups, whereas physiological responses relative to maximal and ventilatory threshold values were greater in the 40-45 yr. group than the other two groups. Nevertheless, perceptual and affective responses were similar for all age groups. These findings suggest that physiological responses, but not perceptual and affective responses, of sedentary women are associated with age during walking at a self-selected pace. DOI 10.2466/06.10.13.PMS.111.6.963-978

Relations between duration judgments and verbal or visual working memory, between duration judgments and effect of learning to plan the processing of information about such judgments were investigated. A computer monitor was used to present images of two cars traveling in the same direction for various durations and distances. Participants (N = 30) were asked to identify the car that had traveled for the longer duration. Then, participants learned how to solve Piagetian tasks logically. After the learning, they tried to solve the duration judgments task again. Finally, their verbal and visual working memory capacities were assessed. Results indicated the following: (a) numbers of correct answers on the Piagetian tasks were correlated with verbal and visual working memory capacity; (b) the correlations did not significantly decrease after the participants learned how to solve the Piagetian tasks. DOI 10.2466/04.10.22.PMS.111.6.863-871

Strategies for finding one's way through an unfamiliar environment may be helped by 2D maps, 3D virtual environments, or other navigation aids. The relative effectiveness of aids was investigated. Experiments were conducted in a large, park-like environment. 24 participants (12 men, 12 women; age range = 2250 years; M = 32, SD = 7.4) were divided into three groups of four individuals, who explored a 2D map of a given route prior to navigation, received a silent guided tour by means of an interactive virtual representation, or acquired direct experience of the real route through a silent guided tour. Participants then had to find the same route again on their own. 12 observers were given a 'simple' route with only one critical turn, and the other 12 a 'complex' route with six critical turns. Compared to three people familiar with the routes, among the naive participants, those who had a direct experience prior to navigation all found their way again on the simple and complex routes. Those who had explored the interactive virtual environment were unable to find their way on the complex route. The relative scale representation in the virtual environment may have given incorrect impressions of relative distances between objects along the itinerary, rendering important landmark information useless. DOI 10.2466/04.22.23.27.PMS.111.6.829-847

This investigation examined the validity of newly developed Adult OMNI Elliptical Ergometer Ratings of Perceived Exertion Scales. 60 men and women performed a graded exercise test on an elliptical ergometer. Oxygen consumption (V[O.sub.2]), heart rate (HR), and ratings of perceived exertion were recorded at each stage from the Borg 15 Category scale and two different OMNI scales. One scale employed an elliptical ergometer format of the OMNI Picture System of Perceived Exertion. The second scale modified verbal, numerical, and pictorial descriptors at the low end of the response range. Concurrent and construct validity were established by the positive relation between ratings of perceived exertion from each OMNI scale with V[O.sub.2], HR, and Borg scale ratings of perceived exertion (men, r= .94-.97; women, r = .93-.98). Validity was established for both OMNI scales, indicating either metric can be used to estimate ratings of perceived exertion during partial weight-bearing exercise. DOI 10.2466/05.06.PMS.111.6.848-862

98 undergraduates (54 men, 44 women) participated in an experiment to examine whether having an artificially furrowed brow would have an effect on participants' subjective impression of perceived targets. An elastic adhesive bandage was either stretched to create furrows on the brow when it retracted, or not stretched so as to avoid creating wrinkles. While wearing the bandages, the participants rated their impressions of neutral targets preceded by agreeable, disagreeable, or neutral primes in a modified Affect Misattribution Procedure. The results showed that participants with artificially furrowed brows tended to rate the neutral targets preceded by agreeable primes less favorably than did the control participants, while both groups rated similarly the targets preceded by disagreeable primes. DOI 10.2466/02.07.24.PMS.111.6.785-789

The first objective was to assess whether healthy individuals could accurately estimate their weight-bearing distribution in sit-to-stand transfers. The second was to evaluate the effect of age on weight-bearing perception. 16 young participants (11 women, 5 men; M age 29 yr., SD=8.7) and 15 elderly participants (7 women, 8 men; M age 65 yr., SD=3.8) were recruited. Verbal instructions and visual feedback referring to different percentages of weight-bearing distribution to execute were used to quantify weight-bearing perception in sit-to-stand tasks. For the feedback approach, the perception was assessed with a visual analog scale. For the verbal task, the weight-bearing distribution produced was assessed with force plates. Both young and elderly participants had good perception of weight-bearing distribution, with mean absolute errors of 6.4%. Moreover, their perceived and real weight-bearing distribution showed good agreement (ICC [greater than or equal to] .79). DOI 10.2466/03.15.25.PMS.111.4.187-198

The Ternus display is an ambiguous, multi-element, apparent-movement animation which can be perceived in two alternative organizations. One of these involves the simultaneous movement of several elements and is called group movement. The other involves the movement of one element only and is called element movement. The present study examined the influence of retinal eccentricity and organizational orientation on the percentage of group-movement reports obtained across a range of interstimulus intervals. Six participants observed 48 variations of the Ternus display over 100 replications and judged the type of movement seen on each trial. Analysis showed that retinal eccentricity had no effect on the appearance of the display. However, compared with horizontally organized elements, obliquely organized and vertically organized elements yielded progressively more group movement across all but the shortest interstimulus intervals. These results represent an orientational anisotropy in the processing of Ternus apparent movement.

Nakamura, et al. recently showed that pigeons experience the standard Muller-Lyer illusion but not the reversed illusion induced by detaching the arrowheads from the target line. This study re-examined pigeons' perception of this reversed figure by using the stimuli known to induce the maximal contrast effect in humans (Fellows, 1967). Pigeons were retrained to classify six lengths of target lines into 'long' and 'short' categories by pecking two keys on the monitor, ignoring the two brackets so placed that these would not induce an illusion. In the test that followed, two birds' responses were not affected by directions of arrowheads, as shown in the previous study. The third pigeon significantly chose 'long' for inward-pointing brackets figures (> ), that is, the direction of illusion was reversed from what is expected in humans. These results suggest that pigeons may not experience illusions induced by contrast with the surrounding stimuli.

Neuropsychological tests were administered to 62 college students to assess the influence of glyconutrients on perception, cognition and memory in two randomized, double-blind, placebo-controlled, counterbalanced studies. Participants were given both a glyconutritional supplement and a control substance prior to testing. In Exp. 1, a Same-Different visual discrimination task, Raven's Standard Progressive Matrices, and the Stroop test were administered. In Exp. 2, simple and complex working-memory capacity were measured. Participants receiving the supplement performed significantly more accurately on the visual discrimination task and the first session of the simple working-memory test.

Difficulties in identifying and differentiating one's emotions are a central characteristic of alexithymia. In the present study, automatic activation of the fusiform gyrus to facial emotion was investigated as a function of alexithymia as assessed by the 20-item Toronto Alexithymia Scale. During 3 Tesla fMRI scanning, pictures of faces bearing sad, happy, and neutral expressions masked by neutral faces were presented to 22 healthy adults who also responded to the Toronto Alexithymia Scale. The fusiform gyrus was selected as the region of interest, and voxel values of this region were extracted, summarized as means, and tested among the different conditions (sad, happy, and neutral faces). Masked sad facial emotions were associated with greater bilateral activation of the fusiform gyrus than masked neutral faces. The subscale, Difficulty Identifying Feelings, was negatively correlated with the neural response of the fusiform gyrus to masked sad faces. The correlation results suggest that automatic hyporesponsiveness of the fusiform gyms to negative emotion stimuli may reflect problems in recognizing one's emotions in everyday life.

Does consciousness have a spatial 'location' that can be scientifically investigated? Using a novel phenomenological method, when people are encouraged to explore the question introspectively they not only can make sense of the idea of their consciousness being 'located,' but will readily indicate its exact position inside the head. The method, based on Francisco J. Varela's work, involves a structured interview led by an expert mediator in which preliminary questions are asked of untrained volunteers about the location of objects and body parts, and then they are questioned about the location from which they are experiencing these objects. 83% of volunteers located with confidence a precise position for the I-that-perceives in the temporal area of the head centred midway behind the eyes. The same results were obtained with blind subjects (congenitally or later) and with non-Westerners. The significance of this subjective source of the experience of the location of perception is discussed linking it to neurological correlates of self-referred conscious activities and of conscious awareness in memory. Further investigations are suggested with trained volunteers and with individuals with psychiatric disorders.

It was hypothesized that a specialized gait recognition skill enables humans to distinguish the gait of familiar from unfamiliar individuals, and that this may have relevance in team sports. Runners seen for less than half a second can be classified as teammates or not by adult players, so it may be asked whether this skill would also be demonstrated by young team players. In the current study, junior football players (M age = 10.0 yr., SD = 0.8, N = 13) viewed 400-msec. video clips of runners sprinting past a fixed forward facing digital video camera and similarly showed teammate recognition scores significantly above chance. Given the variation among the junior players in this skill, it seems possible for researchers to assess whether improvement can be obtained with structured training for young team players, where running teammates are seen in peripheral vision during training drills.

In two experiments, new illusions of size were created using stimuli composed of nine trees, otoscopes, pens, hourglasses, hands, or mailboxes. The size of the nine objects varied across space in accordance with a Mach pattern. At the small side of the stimuli where there were three objects of identical size, the object at the inflection point was seen as smallest; at the large side of the stimuli where there were also three objects of equal size, the object at the inflection point was seen as largest. In Exp. 3, isolated objects and objects at the inflection points of the Mach stimuli were compared. When the stimuli were oriented to place the judged objects at the inflection points near the isolated object, figures with both pens and otoscopes at the small side of the pattern were underestimated and the figures of pens and otoscopes at the large side of the pattern were overestimated. These illusions resemble Brigner and Kauffman's Mach lines illusion and appear to result from interaction among visual neurons which are encoding the size of complex objects by frequency of their response.

This article presents four new studies on the efficacy of predictions based on prospect and refuge theory and summarizes the results over eight studies. New data covered 49 participants and 36 environments. The eight studies included in the summary covered 144 participants and 80 widely diverse environments (Japanese Tatami rooms, Western rooms, porch, meadow, neighborhood commercial, shopping mall, vacation landscapes). Data were available for hypotheses about five factors: prospect, refuge, light, venue, and spatial transition. Efficacy was represented by correlations for the levels of the factors with responses of preference or comfort. Overall, venue was the most efficacious factor (r = .42, 95% CI = .14, .64). Efficacies for the other factors were very near zero. It is suggested that a considerable amount of additional formal inquiry be conducted before assuming the utility of prospect and refuge theory.

Previous research has shown that timesharing ability--the ability to perform multiple tasks simultaneously--is related to various indices of aircraft pilots' proficiency. Superior timesharing has also been demonstrated by experienced pilots. The present study examined timesharing of United States Air Force Reserve Officer Training Corps (AFROTC) cadets, who are relatively inexperienced (some with no flying experience). 10 AFROTC cadets (M age = 21.4 yr., SD = 1.0) and 18 noncadets (M age = 19.8 yr., SD = 0.9) were evaluated. Participants performed a tracking task on the Multi-Attribute Task battery in a single-task condition, a dual-task condition, and a tri-task condition. Cadets' tracking performance was superior to that by noncadets in the dual-task and tri-task conditions.

The aim of this study was to explore the latent affective and persuasive meaning attributed to text when appearing in two commonly used fonts. Two satirical readings were selected from the New York Times. These readings (one addressing government issues, the other education policy) were each printed in Times New Roman and Arial fonts of the same size and presented in randomized order to 102 university students, who ranked the readings on a number of adjective descriptors. Analysis showed that satirical readings in Times New Roman were perceived as more funny and angry than those in Arial, the combination of emotional perception which is congruent with the definition of satire. This apparent interaction of font type with emotional qualities of text has implications for marketing, advertising, and the persuasive literature.

It has been generally assumed that fat is detected by its flavour and by its lubrication of the oral mucosa. A recent study reported a correlation of -.99 between perceived temperature of a product and its fat content. This was significantly higher than correlations of sensory scores for fat flavour, mouthfeel, and afterfeel. This suggested a third detection mechanism; fat may be detected via its effect on the thermal conductivity of the food. In 3 studies, thermal sensitivity in humans was investigated to verify whether oral thermal receptors are sufficiently rapid and accurate to play a role in the perception of fats. The thermal sensitivity of the lips and oral mucosa of the anterior and middle one-third of the tongue were assessed using a Peltier device. Subjects detected 0.5 Hz fluctuations in temperature of 0.08[degrees]C on the lower lip, 0.26[degrees]C and 1.36[degrees]C at the tip and dorsum of the tongue, demonstrating that the lips are sufficiently sensitive to detect small differences in temperature. In two further experiments subjects ingested custards and mayonnaises and then spat out samples after 5, 10, or 20 sec. The temperature of the food and oral mucosa was measured before and after spitting and the rates of heating were calculated. Results suggest assessment of thermal conductivity of food may be used to assess fat content.

The literature reports that focused attention alters perceived length of lines. Some tests of this attentional effect require that subjects compare line lengths. This note shows that conceptual confusions inherent in this comparison make the tests invalid.