PubMed HealthSearch

SEARCH · PubMed Health

Results for “Visual Perception”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 199 records · Page 11Linked to original sources

Testing visual perception of three-dimensionally moving objects (dynamic stereoscopy).

In the past decade, visual requirements in the field of stereoscopy have considerably increased in a number of professions, as well in present-day traffic and sports. As a result of a statement of the WHO (1984) viz. that for prevention of accidents the testing of static vision only is insufficient, and that dynamic vision too should be a subject of investigation, a test for measuring dynamic stereoscopic visual acuity has been devised. With the help of two synchronously rotating prisms, a stereo test consisting of four bars is transposed into an apparent circumduction movement which is presented at different velocities. Stereoscopy under static and dynamic conditions do not run a parallel course. Dynamic stereoscopy is significantly influenced by age, but not by sex.

Adult

Lateral asymmetries in visual perception with and without eye movements.

A signal detection analysis was made of single letter recognition in the right and left visual fields. When letters were presented 2 degrees 3' to the right or left of a central fixation there were no significant differences between the fields in perceptual accuracy independent of bias when the subject maintained a central fixation point. However, when subjects were free to move their eyes a right field advantage was found. The results were discussed in terms of attentional bias theories and hemispheric specialization theories.

Cerebral Cortex

[Ontogenetic characteristics of the development of slow negative and positive potentials during the performance of a visual perceptive task].

In age aspect, topography and parameters were studied of late EPs and slow negative components (CNV) to successively presented visual stimuli: the preliminary signal and two compared contour images. Age characteristics of development of the frontal negativity N450 and the late positive complex (LPC) were revealed. in children 7 and 10 years old, the component N450 was present in response both to the preliminary and the first stimulus in the compared pair; LPC was recorded to all three presented visual stimuli. In 17 years old subjects and in adults, selectivity of N450 formation in the EP to the first of the compared stimuli and LPC to the second (imperative) stimulus correlates with involvement of rostral brain areas--central in youths, central and frontal ones in adults--both in the process of waiting (CNV) and evaluation of coming information (LPC).

Adolescent