275 research outputs found
Spatial frequency tuning of the Ouchi illusion and its dependence on stimulus size
AbstractThis study investigated the effects of the stimulus size on the spatial frequency tuning of the Ouchi illusion, which is an illusory sliding motion perceived in a checkerboard pattern of rectangular elements that is surrounded by a checkerboard pattern of orthogonally oriented elements. Two experiments were conducted to measure the perceived strength of illusion. The optimal size of the inner pattern increased proportionally with check size. In contrast, the optimal check size increased with the size of the inner pattern but not proportionally, and the range of increase was relatively small. The optimal fundamental spatial frequency was lower for a larger stimulus both for checkerboard patterns and simpler sinusoidal grating patterns, but there were differences in the tuning curves for the two types of stimuli. These results support the idea that two processes underlie the Ouchi illusion; one computes the local motion direction, and the other integrates motion signals across space for surface segmentation. For the checkerboard and grating stimuli, the former process may be different while the latter can be shared
Priming and implicit recognition depend on similar temporal changes in perceptual representations.
Previous studies have reported that longer stimulus presentation decreases the magnitude of priming. In the present study, we used meaningless kaleidoscope images, which were reported to minimize conceptual processing, to investigate the mechanism of the phenomenon. We assessed the impact of stimulus duration on perceptual priming (Experiment 1) and implicit recognition memory (Experiment 2). Both the magnitude of priming and the accuracy of implicit recognition were lower with the longer stimulus presentation (350ms) compared with the shorter presentation (250ms). This coincidence of temporal dynamics between priming and implicit recognition suggests similar underlying memory mechanisms. In both cases, the decrease of performance with longer presentation can be explained by either changes in perceptual processes or interference from explicit memory retrieval
Erratum to “A motion aftereffect seen more strongly by the non-adapted eye: evidence of multistage adaptation in visual motion processing” [Vision Research 41 (2001) 561–570]
Larger Head Displacement to Optic Flow Presented in the Lower Visual Field
Optic flow that simulates self-motion often produces postural adjustment. Although literature has suggested that human postural control depends largely on visual inputs from the lower field in the environment, effects of the vertical location of optic flow on postural responses are not well investigated. Here, we examined whether optic flow presented in the lower visual field produces stronger responses than optic flow in the upper visual field. Either expanding or contracting optic flow was presented in upper, lower, or full visual fields through an Oculus Rift head-mounted display. Head displacement and vection strength were measured. Results showed larger head displacement under the optic flow presentation in the full visual field and the lower visual field than the upper visual field, during early period of presentation of the contracting optic flow. Vection was strongest in the full visual field and weakest in the upper visual field. Our findings of lower field superiority in head displacement and vection support the notion that ecologically relevant information has a particularly important role in human postural control and self-motion perception
Effect of repeated Waon therapy on exercise tolerance and pulmonary function in patients with chronic obstructive pulmonary disease: a pilot controlled clinical trial
Purpose: Controlled clinical trials evaluating the efficacy of repeated Waon therapy for patients with chronic obstructive pulmonary disease (COPD) have yet to be conducted. The purpose of the present study was to evaluate whether repeated Waon therapy exhibits an adjuvant effect on conventional therapy for COPD patients.
Patients and methods: This prospective trial comprised 20 consecutive COPD patients who satisfied the criteria of the Global initiative for chronic Obstructive Lung Disease (GOLD) guidelines, stages 1–4. They were assigned to either a Waon or control group. The patients in the Waon group received both repeated Waon therapy and conventional therapy, including medications, such as long-acting inhaled β2 agonists, long-acting anticholinergics and xanthine derivatives, and pulmonary rehabilitation. The Waon therapy consisted of sitting in a 60°C sauna room for 15 minutes, followed by 30 minutes of being warmed with blankets once a day, 5 days a week, for a total of 20 times. The patients in the control group received only conventional therapy. Pulmonary function and the 6-minute walk test were assessed before and at 4 weeks after the program.
Results: The change in vital capacity (0.30 ± 0.4 L) and in peak expiratory flow (0.48 ± 0.79 L/s) in the Waon group was larger than the change in the vital capacity (0.02 ± 0.21 L) (P=0.077) and peak expiratory flow (−0.11 ± 0.72 L/s) (P=0.095) in the control group. The change in forced expiratory flow after 50% of expired forced vital capacity in the Waon group, 0.08 (0.01–0.212 L/s), was larger than that in the control group, −0.01 (−0.075–0.04 L/s) (P=0.019). Significant differences were not observed in the change in any parameters in the 6-minute walk test. Data are presented as means ± standard deviation or median (25th–75th percentile).
Conclusion: The addition of repeated Waon therapy to conventional therapy for COPD patients can possibly improve airway obstruction
Low-level laser therapy for spinal cord injury in rats: effects of polarization
Abstract. The effects of laser polarization on the efficacy of near-infrared low-level laser therapy for spinal cord injury (SCI) are presented. Rat spinal cords were injured with a weight-drop device, and the lesion sites were directly irradiated with a linearly polarized 808-nm diode laser positioned either perpendicular or parallel to the spine immediately after the injury and daily for five consecutive days. Functional recovery was assessed daily by an open-field test. Regardless of the polarization direction, functional scores of SCI rats that were treated with the 808-nm laser irradiation were significantly higher than those of SCI alone group (Group 1) from day 5 after injury. The locomotive function of SCI rats irradiated parallel to the spinal column (Group 3) was significantly improved from day 10 after injury, compared to SCI rats treated with the linear polarization perpendicular to the spinal column (Group 2). There were no significant differences in ATP contents in the injured tissue among the three groups. We speculate that the higher efficacy with parallel irradiation is attributable to the deeper light penetration into tissue with anisotropic scattering
Glowing gold nanoparticle coating: restoring the lost property from bulk gold
ArticleNanoscale. 11(9): 3786-3793. (2019)journal articl
Longer prime presentation decreases picture–word cross-domain priming
A short prime presentation has been shown to provide a greater priming magnitude, whereas a longer prime presentation results in a lower priming magnitude. In Experiment 1, we attempted to replicate the decrease of priming using word stimuli. Words were presented in both prime and test sessions, and participants judged whether each stimulus was natural or manmade. In Experiment 2, we employed a cross-domain priming paradigm to assess the impact of prime duration on non-perceptual processes. Pictures were presented in prime sessions, and their semantically matched words were presented in test sessions. We did not observe a significant decrease in priming in Experiment 1. However, we found that 2000 ms of prime exposure led to weaker cross-domain priming when compared with 250 ms of the exposure in Experiment 2. The results suggest that the longer presentation of pictures causes a non-perceptual adaptation effect. This effect may occur at conceptual, linguistic, and/or response-related levels
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