PubMed HealthSearch

SEARCH · PubMed Health

Results for “Perceptual Masking”

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 19 recordsLinked to original sources

Stimulus repetition effects and the dimension-feature distinction in alternative targets.

The negative repetition effect (NRE) refers to a poorer perception of the target in noise-same-as-target than in noise-alternative-target displays. Using the parenthesis as target and noise that are either identical or different in orientation, we tested predictions derived from a feature-specific inhibition model (Bjork & Murray, 1977) that explains the NRE as arising from inhibitory interactions among channels handling identical inputs. Contrary to our expectation of evidence for orientation-specific inhibition, a positive repetition effect (PRE) was observed. We also found a PRE for the dimension target sets whose stimuli differ only in orientation and an NRE for the feature target sets whose stimuli differ in the number of elements. Further experiments that systematically varied relationships between alternative targets indicate that these basic findings, termed the stimulus attributes effects, do not arise from pattern masking, perceptual strategies, or response bias.

Adult

How visual imagery interferes with vision.

Mental visual imagery interferes with vision: the Perky (1910) effect. Is the effect optical, sensory, perceptual, attentional, or just a response bias? Acuity was measured (in undergraduates and graduates) using target lines, with and without images (of lines). Optics (fixation, pupil size, accommodation), response bias, global attention (effort; diversion of attention to imagery), perceptual assimilation (target incorporation by imagery) and perceptual masking (of target by imagery) all fail to explain the effect. Foveally, local attention plays a limited role, as the Perky effect in divided attention is half that in focused attention, but this interaction vanishes with extrafoveal targets. Images produce primarily sensory interference, mimicking a reduction in target energy.

Adult

Age differences in central perceptual processing: a dichoptic backward masking investigation.

Age differences in central perceptual processing were investigated using young (mean age 19.5 years) and old (mean age 64.2 years) subjects in a backward masking paradigm known to produce central interference. Subjects were presented with symmetrical, straight-lined letters as target stimuli (TS). The masking stimulus (MS) was a pattern of line segments of the same width as the strokes of the letters spaced evenly over the part of the visual field occupied by the letters. The TS was presented to the right eye and followed by the MS to the left eye. A robust masking effect was found for both young and old across conditions in which TS energy was much greater than MS energy. The asynchrony between TS and MS onset (SOA) was found to be the variable describing escape from masking for both age groups. However, the older group required 24% longer SOAs than the young to escape masking, suggesting a slowing with age in central perceptual processing.

Adult

Age differences in peripheral perceptual processing: a monoptic backward masking investigation.

Peripheral processes in vision were investigated in two experiments involving monoptic backward masking with random noise. For young and old subjects, peripheral processing time (represented by stimulus onset asynchrony of target and mask) was characterized as a power function of target energy. Although processing time for both age groups showed a similar rate of decline with increasing target energy, old subjects processed targets more slowly at all energy levels. Results were independent of education, sex, and criterion differences between young and old. Target duration was related to critical interstimulus interval, such that stimulus onset asynchrony between target and mask was approximately constant for a given target energy within each age group. Evidence suggests that peripheral processing begins with target onset and that processing time is best characterized by a power function relating stimulus onset asynchrony of target and mask to target energy.

Adult

Effects of lateral masking and spatial precueing on gap-resolution in central and peripheral vision.

The data made available by this experiment add two points to the information obtained by previous studies on eccentric vision and lateral masking. First, they demonstrate a clear effect of target-mask similarity on visual gap-resolution in eccentric vision: increasing target-mask similarity systematically decreases resolution performance. Second, spatial precueing has no effect on gap-resolution performance. One implication of this experiment is that with the present stimulus configurations, visual resolution should decrease much more strongly with eccentricity than it does with classical isolated or bar-masked optotypes.

Humans