Search PubMed⌕ Search

PubMed · 10607397

Touch can change visual slant perception.

Abstract

The visual system uses several signals to deduce the three-dimensional structure of the environment, including binocular disparity, texture gradients, shading and motion parallax. Although each of these sources of information is independently insufficient to yield reliable three-dimensional structure from everyday scenes, the visual system combines them by weighting the available information; altering the weights would therefore change the perceived structure. We report that haptic feedback (active touch) increases the weight of a consistent surface-slant signal relative to inconsistent signals. Thus, appearance of a subsequently viewed surface is changed: the surface appears slanted in the direction specified by the haptically reinforced signal.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

M O Ernst, M S Banks, H H Bülthoff. 2000. Touch can change visual slant perception.. https://doi.org/10.1038/71140

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Verbal feedback from an expert is more effective than self-accessed feedback about motion efficiency in learning new surgical skills.

BACKGROUND: Teaching of technical surgical skills to undergraduate medical students in a laboratory setting away from the patient is not common practice. Because of the large volume of students and shortage of available teaching faculty new methods of teaching must be developed for this group of trainees. In this study we examined the effectiveness of computer-based video training, different types of computer-based motion efficiency feedback (with and without expert criteria), and expert feedback on learning of a basic technical skill in medical students. METHODS: Forty-five junior medical students were randomized into 3 groups and learned suturing and knot-tying skills. Group A received computer-generated feedback about the economy of their movements. Group B received the same motion economy feedback, as well as expert reference values. Group C received verbal feedback from an expert. All groups were pre-tested, allowed 18 practice trials, and post-tested, and their skill retention was retested after 1 month. Performance was assessed by expert analysis using an objective structured analysis of technical skill and by computer analysis (Imperial College Surgical Assessment Device [ICSAD]). RESULTS: All groups showed improvement from pre-test to post-test. However, only group C showed retention of skill on delayed performance testing. CONCLUSIONS: Verbal feedback from an expert instructor led to lasting improvements in technical skills performance. Providing information about motion efficiency did not lead to similar improvements.

Biofeedback, Psychology↗

Efficacy of biofeedback for migraine: a meta-analysis.

In this article, we meta-analytically examined the efficacy of biofeedback (BFB) in treating migraine. A computerized literature search of the databases Medline, PsycInfo, Psyndex and the Cochrane library, enhanced by a hand search, identified 86 outcome studies. A total of 55 studies, including randomized controlled trials as well as pre-post trials, met our inclusion criteria and were integrated. A medium effect size (d =0.58, 95% CI=0.52, 0.64) resulted for all BFB interventions and proved stable over an average follow-up phase of 17 months. Also, BFB was more effective than control conditions. Frequency of migraine attacks and perceived self-efficacy demonstrated the strongest improvements. Blood-volume-pulse feedback yielded higher effect sizes than peripheral skin temperature feedback and electromyography feedback. Moderator analyses revealed BFB in combination with home training to be more effective than therapies without home training. The influence of the meta-analytical methods on the effect sizes was systematically explored and the results proved to be robust across different methods of effect size calculation. Furthermore, there was no substantial relation between the validity of the integrated studies and the direct treatment effects. Finally, an intention-to-treat analysis showed that the treatment effects remained stable, even when drop-outs were considered as nonresponders.

Biofeedback, Psychology↗