Impact of Background, Foreground, and Manipulated Object Rendering on Egocentric Depth Perception in Virtual and Augmented Indoor Environments.

This research investigated how the similarity of the rendering parameters of background and foreground objects affected egocentric depth perception in indoor virtual and augmented environments. We refer to the similarity of the rendering parameters as visual 'congruence'. Study participants manipulated the depth of a sphere to match the depth of a designated target peg. In the first experiment, the sphere and peg were both virtual, while in the second experiment, the sphere is virtual and the peg is real. In both experiments, depth perception accuracy was found to depend on the levels of realism and congruence between the sphere, pegs, and background. In Experiment 1, realistic backgrounds lead to overestimation of depth, but resulted in underestimation when the background was virtual, and when depth cues were applied to the sphere and target peg. In Experiment 2, background and target pegs were real but matched with the virtual sphere; in comparison to Experiment 1, realistically rendered targets prompted an underestimation and more accuracy with the manipulated object. These findings suggest that congruence can affect distance estimation and the underestimation effect in the AR environment resulted from increased graphical fidelity of the foreground target and background.

Research in visual pattern recognition: the enduring legacy of studies from the 1960s.

This article highlights some research in visual pattern perception that was published in the American Journal of Psychology in the 1960s. Although visual perception research has changed substantially since then, and the term visual pattern recognition is no longer in widespread use, the six articles presented here are some of the most influential of those published by the Journal in its long history. The research is described with an emphasis on how a particular publication influenced others and the field in general.

Reliability, validity, and responsiveness of the Japanese version of the Neck Pain and Disability Scale.

BACKGROUND: Until recently, no Japanese versions have existed of the more popular, patient-reported disability questionnaires for neck pain. This study aimed to test the reliability, validity, and responsiveness of the Japanese version of the Neck Pain and Disability Scale (NPDS), one of the most widely used questionnaires in patients with neck pain. METHODS: In this validation study, 167 outpatients with neck pain participated. Patients received the NPDS and the Medical Outcome Study Short Form 36-item Health Survey (SF-36), and used Visual Analog Scales (VASs) to assess pain and global health. To examine test-retest reliability, patients who were considered stable by clinicians were given the NPDS 2 weeks after baseline. To examine responsiveness, patients who had not undergone treatment at the time of the first data collection or had no change in treatment over 3 months were studied again 2 weeks after starting a new medication or physical therapy. RESULTS: Of the 167 participants, 143 completed the questionnaires (85.6%). Factor analysis showed two factors, defined as neck-pain-related disability (factor 1) and neck-related pain (factor 2). Cronbach's α coefficient for factor 1, factor 2, and total score was 0.94, 0.93, and 0.96. The intra-class correlation coefficients for the 19 more stable patients were 0.79, 0.88, and 0.87. For concurrent validity, the correlation between NPDS subscales and total score and SF-36 subscale scores ranged from r = -0.54 to -0.22 (p < 0.01). Correlations between the NPDS subscales and total score and VAS of pain ranged from 0.56 to 0.77 (p < 0.01) and those for VAS of global health ranged from 0.48 to 0.63 (p < 0.01). The NPDS subscales and total scores of the 41 patients retested after treatment were significantly improved. CONCLUSIONS: The Japanese version of the NPDS is a useful scale with reliability, validity, and responsiveness in assessing patients suffering from neck pain.

Perceptual comparisons with laterally presented pictures and environmental sounds.

Two experiments studied perceptual comparisons with cues that vary in one of four ways (picture, sound, spoken word, or printed word) and with targets that are either pictures or environmental sounds. The basic question probed whether modality or differences in format were factors that would influence picture and sound perception. Also of interest were cue effect differences when targets are presented on either the right or left side. Students responded to a same-different reaction time task that entailed matching cue-target pairs to determine whether the successive stimulus events represented features drawn from the same basic item. Cue type influenced reaction times to pictures and environmental sounds, but the effects were qualified by response type and with picture targets by presentation side. These results provide some additional evidence of processing asymmetry when pictures are directed to either the right or left hemisphere, as well as for some asymmetries in cross-modality cuing. Implications of these findings for theories of multisensory processing and models of object recognition are discussed.

Mindfulness meditation improves cognition: evidence of brief mental training.

Although research has found that long-term mindfulness meditation practice promotes executive functioning and the ability to sustain attention, the effects of brief mindfulness meditation training have not been fully explored. We examined whether brief meditation training affects cognition and mood when compared to an active control group. After four sessions of either meditation training or listening to a recorded book, participants with no prior meditation experience were assessed with measures of mood, verbal fluency, visual coding, and working memory. Both interventions were effective at improving mood but only brief meditation training reduced fatigue, anxiety, and increased mindfulness. Moreover, brief mindfulness training significantly improved visuo-spatial processing, working memory, and executive functioning. Our findings suggest that 4days of meditation training can enhance the ability to sustain attention; benefits that have previously been reported with long-term meditators.

Age differences and format effects in working memory.

Format effects refer to lower recall of printed words from working memory when compared to spoken words or pictures. These effects have been attributed to an attenuation of attention to printed words. The present experiment compares younger and older adults' recall of three or six items presented as pictures, spoken words, printed words, and alternating case WoRdS. The latter stimuli have been shown to increase attention to printed words and, thus, reduce format effects. The question of interest was whether these stimuli would also reduce format effects for older adults whose working memory capacity has fewer attentional resources to allocate. Results showed that older adults performed as well as younger adults with three items but less well with six and that format effects were reduced for both age groups, but more for young, when alternating case words were used. Other findings regarding executive control of working memory are discussed. The obtained differences support models of reduced capacity in older adult working memory.

Low Vitamin D States Observed in U.S. Marines and Navy Sailors with Early Multi-Symptom Illness.

Research has implicated immune system inflammation as an underlying etiology of multi-symptom illnesses, and vitamin D has been shown to have a significant role in immune system function. In this retrospective review performed on the medical charts of service members who presented with signs and symptoms of multi-symptom illnesses, we focused on serum 25(OH)D3 levels and looked for associations of vitamin D status (deficient, insufficient, and normal) with age (20-31 years versus 31-56 years) and deployment status (war zones versus other). Two groups (U.S. Marines and Navy Sailors) were sampled and both showed high incidences of below normal vitamin D levels. However, with the Marines, age-related differences in serum levels (p = 0.009) were found only among those who deployed to Iraq/Afghanistan in comparison to those in non-combat locations. The comparison within the Navy sample showed that mobilized sailors had lower 25(OH)D3 levels than the group that did not deploy (p = 0.04). In addition, 100% of the sailors who deployed had below normal levels versus only 33% in the cadre group. The data suggest that personnel returning from a war zone with signs of early multi-symptom illness should be checked for low vitamin D status.

Modality effects in sentence recall.

The authors examined the intrusion of lures into sentence recall when manipulating the modality of distractor-word lists and sentences separately. Participants received a list of words followed by a sentence, and the list did or did not contain a lure related to a target in the sentence. Conceptual regeneration of the sentence during recall predicted higher lure intrusions than spontaneous intrusions in all conditions. However, if surface information is remembered, the modality of sentence and list should influence intrusions. The results from Experiment 1 showed that both factors are important, as intrusions were always higher when lures were contained in the distractor-word list and when visual, rather than auditory, sentences were recalled. The authors also found distractor modality to influence the results. In Experiment 2, when interference from the word probe was reduced by removing 40% of the word probes, the disruptive effect of the auditory distractors was attenuated on the trials without the word probe. Also, the authors found lure intrusions to be dependent on the presence of the word probe.

Video Games and Stress: How Stress Appraisals and Game Content Affect Cardiovascular and Emotion Outcomes.

Although previous studies have found that video games induce stress, studies have not typically measured all salient indicators of stress responses including stress appraisals, cardiovascular indicators, and emotion outcomes. The current study used the Biopsychosocial Model of Challenge and Threat (Blascovich and Tomaka, 1996) to determine if video games induce a cardiovascular stress response by comparing the effects of threat and challenge appraisals across two types of video games that have shown different cardiovascular outcomes. Participants received challenge or threat appraisal instructions, and played a fighting game (Mortal Kombat) or a puzzle game (Tetris). Study outcomes were heart rate variability, systolic and diastolic blood pressure, and positive and negative emotion ratings measured before, during and after gameplay. Results indicated that threat appraisal instructions increased negative emotion ratings and decreased heart rate variability, but not blood pressure, which is an essential marker for cardiovascular stress responses. Increased blood pressure and decreased heart rate variability was associated with fighting game players when compared with the puzzle game players, indicating a cardiovascular stress response; however, fighting game players also reported higher positive emotion ratings. Based on the study findings, video games do not induce stress responses like mental stressors used in previous research, demonstrating that the interactive player experience in video gaming may have more complex effects on stress outcomes. Future research should comprehensively measure biopsychosocial stress indicators and multiple emotional states over time to fully examine the relationship between video games and stress.

Presentation format effects in a levels-of-processing task.

Three experiments were conducted to examine better performance in long-term memory when stimulus items are pictures or spoken words compared to printed words. Hypotheses regarding the allocation of attention to printed words, the semantic link between pictures and processing, and a rich long-term representation for pictures were tested. Using levels-of-processing tasks eliminated format effects when no memory test was expected and processing was deep (El), and when study and test formats did not match (E3). Pictures produced superior performance when a memory test was expected (El & 2) and when study and test formats were the same (E3). Results of all experiments support the attenuation of attention model and that picture superiority is due to a more direct access to semantic processing and a richer visual code. General principles to guide the processing of stimulus information are discussed.

Reduction and elimination of format effects on recall.

Two experiments investigated whether the recall advantage of pictures and spoken words over printed words in working memory (Foos & Goolkasian, 2005; Goolkasian & Foos, 2002) could be reduced by manipulating letter case and sequential versus simultaneous presentation. Participants were required to remember 3 or 6 items presented in varied presentation formats while verifying the accuracy of a sentence. Presenting words in alternating uppercase and lowercase improved recall, and presenting words simultaneously rather than successively removed the effect of presentation format. The findings suggest that when forcing participants to pay attention to printed words you can make them more memorable and thereby diminish or remove any disadvantage in the recall of printed words in comparison with pictures and spoken words.

Open vs. Closed Shapes: New Perceptual Categories?

Effective communication using visualization relies in part on the use of viable encoding strategies. For example, a viewer's ability to rapidly and accurately discern between two or more categorical variables in a chart or figure is contingent upon the distinctiveness of the encodings applied to each variable. Research in perception suggests that color is a more salient visual feature when compared to shape and although that finding is supported by visualization studies, characteristics of shape also yield meaningful differences in distinctiveness. We propose that open or closed shapes (that is, whether shapes are composed of line segments that are bounded across a region of space or not) represent a salient characteristic that influences perceptual processing. Three experiments were performed to test the reliability of the open/closed category; the first two from the perspective of attentional allocation, and the third experiment in the context of multi-class scatterplot displays. In the first, a flanker paradigm was used to test whether perceptual load and open/closed feature category would modulate the effect of the flanker on target processing. Results showed an influence of both variables. The second experiment used a Same/Different reaction time task to replicate and extend those findings. Results from both show that responses are faster and more accurate when closed rather than open shapes are processed as targets, and there is more processing interference when two competing shapes come from the same rather than different open or closed feature categories. The third experiment employed three commonly used visual analytic tasks - perception of average value, numerosity, and linear relationships with both single and dual displays of open and closed symbols. Our findings show that for numerosity and trend judgments, in particular, that different symbols from the same open or closed feature category cause more perceptual interference when they are presented together in a plot than symbols from different categories. Moreover, the extent of the interference appears to depend upon whether the participant is focused on processing open or closed symbols.

Bimodal format effects in working memory.

This work combines presentation formats to test whether bimodal conditions offer advantages or disadvantages relative to single formats in working memory performance. A dual task that included recall of 3 or 6 items while verifying the accuracy of math sentences was used in 2 experiments. When comparisons were made between single- and dual-format conditions, there was an advantage for items presented as spoken words and pictures simultaneously and individually. In Experiment 2, dual-format conditions had incongruent information, and spoken words were found to interfere with recall of long sequences of pictures and printed words. The findings suggest that when dual-format items are the same, there are some performance advantages when spoken words are combined with pictures or printed words. When the dual formats are displaying different items, however, spoken words are a more powerful distractor than pictures or printed words, and verbal and visual short-term stores can demonstrate similar susceptibility to distractor interference.

Target categorization with primes that vary in both congruency and sense modality.

In two experiments we examined conceptual priming within and across sense modalities by varying the modality (picture and environmental sounds) and the category congruency of prime-target pairs. Both experiments used a repetition priming paradigm, but Experiment 1 studied priming effects with a task that required a superordinate categorization response (man-made or natural), while Experiment 2 used a lower level category response (musical instruments or animal): one that was more closely associated with the basic level of the semantic network. Results from Experiment 1 showed a strong effect of target modality and two distinct patterns of conceptual priming effects with picture and environmental sound targets. However, no priming advantage was found when congruent and incongruent primes were compared. Results from Experiment 2, found congruency effects that were specific to environmental sound targets when preceded by picture primes. The findings provide support for the intermodal event file and multisensory framework, and suggest that auditory and visual features about a single item in a conceptual category may be more tightly connected than two different items from the same category.

Pain reactions in pregnant women.

Reactions to radiant heat stimuli were measured in pregnant women and in a control group of non-pregnant women matched in age. Receiver operating characteristic curve parameters were computed for each of the stages of pregnancy from the 6th month until the postpartum period. When painful stimuli were used, a group by stage of pregnancy interaction was found in the analysis on the response criterion for reporting pain. Pregnant women were found to be significantly more willing to label radiant heat stimuli as painful during the last 2 weeks of pregnancy than during any of the other stages of pregnancy. The control women tested during the same time sequence as the pregnant women showed stable response criteria across the 6 month testing period. There were no group or stage of pregnancy effects evident when the discrimination accuracy measures were analyzed; nor were any effects found with responses to thermal stimuli. The results suggest that the changes in pain reaction associated with pregnancy are based on non-sensory factors that influence the subject's willingness to report pain.

Botulinum toxin A for the treatment of chronic neck pain.

A clinical study tested the therapeutic efficacy of Botulinum toxin A (BTXA) when injected into symptomatic neck muscles after one injection session. Patients with chronic neck pain were randomly assigned to receive either a high dose of an active treatment or an injection of the same volume of normal saline. Patients were compared for 4 months using a comprehensive set of outcome measures that included the Neck Pain and Disability Scale (Spine 24 (1999) 1290) and pressure algometry (Arch Phys Med Rehabil 67 (1986) 406; Pain 30 (1987) 115; Clin J Pain 2 (1987) 207). Analyses were consistent in showing significant benefits from the injection session; however, the effects were not specific to the group treated with BTXA. Both treatment and control groups showed a significant decline in pain and disability across time and an increased ability to withstand pressure on trigger points. The heavy incidence of adverse events in the treatment group may partly explain the absence of a treatment effect specific to BTXA. The results show that a single dose treatment without physical therapy is not effective for chronic neck pain.

The neck pain and disability scale: test-retest reliability and construct validity.

OBJECTIVE: This research established test-retest reliability and construct validity for the Neck Pain and Disability Scale (NPAD). METHODS: Two groups of patients with neck pain completed the NPAD. The first group filled out the scale twice before treatment, whereas the second completed it with a number of other outcome measures once a month for 4 months, for evaluation of treatment with injections. RESULTS: The reliability coefficient (r2 = 0.93) calculated from the data for the first group of patients indicated high test-retest reliability. Construct validity was demonstrated with the second group when the NPAD was compared with a number of other pain measures and found to have a larger treatment effect. The Neck Pain and Disability Scale factor scores also indicated that treatment effects varied across the four factors. CONCLUSIONS: The NPAD is a stable and responsive measure for patients with neck pain. The Neck Pain and Disability Scale factor scores are useful in identifying treatment effects on the specific dimensions involved in the pain experience.

Conceptual priming with pictures and environmental sounds.

A series of experiments was conducted to examine conceptual priming within and across modalities with pictures and environmental sounds. In Experiment 1, we developed a new multimodal stimulus set consisting of two picture and sound exemplars that represented 80 object items. In Experiments 2, we investigated whether categorization of the stimulus items would be facilitated by picture and environmental sound primes that were derived from different exemplars of the target items; and in Experiments 3 and 4, we tested the additional influence on priming when trials were consolidated within a target modality and the inter stimulus interval was lengthened. The results demonstrated that target categorization was facilitated by the advanced presentation of conceptually related exemplars, but there were differences in effectiveness when pictures and sounds appeared as primes.

Vitamin D levels and monospot tests in military personnel with acute pharyngitis: a retrospective chart review.

Some recent studies have proposed an important role for vitamin D in reducing the risk of infection by assisting in the suppression of viruses and by controlling the inflammatory response. A low vitamin D state may have a detrimental effect on the immune system's ability to produce activated CD8+ T cells, and it may increase the inflammatory reaction to Epstein Barr virus. The aim of this chart review was to see if serum 25 OH vitamin D3 levels in service members with acute pharyngitis were lower in those who had positive rather than negative monospot tests. A retrospective chart review was conducted on the medical records of service members who presented to sick call at Camp Lejeune, NC with acute pharyngitis from October 8, 2010 until June 30, 2011. Serum 25 OH vitamin D3 levels were compared between those with positive and negative monospot test results. Of the 25 records that were reviewed, there were 9 (36%) service members with positive results, and they were found to have lower vitamin D levels (Median = 20.80 ng/ml, Interquartile range = 10.15) than those with negative test results (Median = 30.35 ng/ml, Interquartile range = 17.05), Mann-Whitney U = 41, p = .039. Only 1 of the 9 with positive test results had a normal serum 25 OH vitamin D3 level (30 ng/ml or greater) compared with 9 of the 16 with negative test results. Optimal vitamin D stores may play a significant role in reducing the risk of developing acute mononucleosis but larger, prospective studies will be needed to verify these findings.