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Consciousness and Cognition Dec 2004Visual stimuli as well as transcranial magnetic stimulation (TMS) can be used: (1) to suppress the visibility of a target and (2) to recover the visibility of a target... (Comparative Study)
Comparative Study Review
Visual stimuli as well as transcranial magnetic stimulation (TMS) can be used: (1) to suppress the visibility of a target and (2) to recover the visibility of a target that has been suppressed by another mask. Both types of stimulation thus provide useful methods for studying the microgenesis of object perception. We first review evidence of similarities between the processes by which a TMS mask and a visual mask can either suppress the visibility of targets or recover such suppressed visibility. However, we then also point out a significant difference that has important implications for the study of the time course of unconscious and conscious visual information processing and for theoretical accounts of the processes involved. We present evidence and arguments showing: (a) that visual masking techniques, by revealing more detailed aspects of target masking and target recovery, support a theoretical approach to visual masking and visual perception that must take into account activities in two separate neural channels or processing streams and, as a corollary, (b) that at the current stage of methodological sophistication visual masks, by acting in more highly specifiable ways on these pathways, provide information about the microgenesis of form perception not available with TMS masks.
Topics: Consciousness; Electromagnetic Fields; Humans; Mental Processes; Perceptual Masking; Skull; Unconsciousness; Visual Perception
PubMed: 15522634
DOI: 10.1016/j.concog.2004.08.007 -
Trends in Cognitive Sciences Feb 2005The ability to remain focused on goal-relevant stimuli in the presence of potentially interfering distractors is crucial for any coherent cognitive function. However,... (Review)
Review
The ability to remain focused on goal-relevant stimuli in the presence of potentially interfering distractors is crucial for any coherent cognitive function. However, simply instructing people to ignore goal-irrelevant stimuli is not sufficient for preventing their processing. Recent research reveals that distractor processing depends critically on the level and type of load involved in the processing of goal-relevant information. Whereas high perceptual load can eliminate distractor processing, high load on "frontal" cognitive control processes increases distractor processing. These findings provide a resolution to the long-standing early and late selection debate within a load theory of attention that accommodates behavioural and neuroimaging data within a framework that integrates attention research with executive function.
Topics: Attention; Field Dependence-Independence; Frontal Lobe; Goals; Humans; Mental Processes; Models, Psychological; Motivation; Perceptual Masking
PubMed: 15668100
DOI: 10.1016/j.tics.2004.12.004 -
Vision Research 1986
Review
Topics: Blinking; Eye Movements; Humans; Light; Perceptual Masking; Saccades; Sensory Thresholds; Visual Perception
PubMed: 3303665
DOI: 10.1016/0042-6989(86)90164-1 -
Attention, Perception & Psychophysics Jan 2013We investigated the physiological mechanism of grapheme-color synesthesia using metacontrast masking. A metacontrast target is rendered invisible by a mask that is...
We investigated the physiological mechanism of grapheme-color synesthesia using metacontrast masking. A metacontrast target is rendered invisible by a mask that is delayed by about 60 ms; the target and mask do not overlap in space or time. Little masking occurs, however, if the target and mask are simultaneous. This effect must be cortical, because it can be obtained dichoptically. To compare the data for synesthetes and controls, we developed a metacontrast design in which nonsynesthete controls showed weaker dichromatic masking (i.e., the target and mask were in different colors) than monochromatic masking. We accomplished this with an equiluminant target, mask, and background for each observer. If synesthetic color affected metacontrast, synesthetes should show monochromatic masking more similar to the weak dichromatic masking among controls, because synesthetes could add their synesthetic color to the monochromatic condition. The target-mask pairs used for each synesthete were graphemes that elicited strong synesthetic colors. We found stronger monochromatic than dichromatic U-shaped metacontrast for both synesthetes and controls, with optimal masking at an asynchrony of 66 ms. The difference in performance between the monochromatic and dichromatic conditions in the synesthetes indicates that synesthesia occurs at a later processing stage than does metacontrast masking.
Topics: Color Perception; Female; Humans; Male; Perceptual Disorders; Perceptual Masking; Photic Stimulation; Synesthesia
PubMed: 23188733
DOI: 10.3758/s13414-012-0401-1 -
Psychonomic Bulletin & Review Feb 2016Object-substitution masking (OSM) is a unique paradigm for the examination of object updating processes. However, existing models of OSM are underspecified with respect...
Object-substitution masking (OSM) is a unique paradigm for the examination of object updating processes. However, existing models of OSM are underspecified with respect to the impact of object updating on the quality of target representations. Using two paradigms of OSM combined with a mixture model analysis we examine the impact of post-perceptual processes on a target's representational quality within conscious awareness. We conclude that object updating processes responsible for OSM cause degradation in the precision of object representations. These findings contribute to a growing body of research advocating for the application of mixture model analysis to the study of how cognitive processes impact the quality (i.e., precision) of object representations.
Topics: Attention; Awareness; Consciousness; Humans; Perceptual Masking; Visual Perception
PubMed: 26082282
DOI: 10.3758/s13423-015-0875-7 -
Perception 1982The suppression effect observed in masking is assumed to be due to neural inhibition between two stimuli that interact spatially or within a narrow span of time in the...
The suppression effect observed in masking is assumed to be due to neural inhibition between two stimuli that interact spatially or within a narrow span of time in the fashion demonstrated in simultaneous brightness-contrast experiments. Three principles are brought together in a comprehensive mathematical model of visual masking. The three principles are: lateral inhibition, the integrated visual response function (VRF), and stimulus decay after its offset over a limited period of time (up to about 100 ms). Block's law is extended to apply to the integration of the VRF, including decay. The three principles combined are sufficient to explain well-known masking phenomena such as metacontrast, and forward and backward masking. The mathematical model presented demonstrates clearly the common underlying basis of all masking. The validity of the lesser documented decay after stimulus offset, a necessary assumption to explain masking effects with stimuli that are delayed relative to each other, is demonstrated with experimental evidence.
Topics: Humans; Mathematics; Models, Neurological; Neural Inhibition; Perceptual Masking; Time Factors; Visual Perception
PubMed: 7182802
DOI: 10.1068/p110427 -
Nature Jan 1999
Topics: Animals; Biological Evolution; Cats; Hearing; Humans; Perceptual Masking; Sensory Thresholds
PubMed: 9923669
DOI: 10.1038/16353 -
Perception & Psychophysics Jan 1984
Topics: Animals; Evoked Potentials, Visual; Humans; Perceptual Masking; Synaptic Transmission; Visual Cortex; Visual Pathways; Visual Perception
PubMed: 6324063
DOI: 10.3758/bf03205926 -
Physiology & Behavior Feb 1979
Topics: Adaptation, Physiological; Adolescent; Adult; Female; Humans; Male; Perceptual Masking; Sodium Chloride; Sucrose; Taste Buds
PubMed: 441173
DOI: 10.1016/0031-9384(79)90097-0 -
British Journal of Audiology Aug 1983Brainstem electric responses (BSER) were recorded simultaneously to give records which were ipsilateral and contralateral to the test ear. Eight normally hearing... (Review)
Review
Brainstem electric responses (BSER) were recorded simultaneously to give records which were ipsilateral and contralateral to the test ear. Eight normally hearing subjects were presented with a fixed stimulus level in one ear and various levels of masking in the other ear. Responses to binaural stimulation were also recorded. It appears from the analysis of results that, for normal subjects, contralateral masking has no statistically significant effect upon the BSER. For the responses obtained from the stimulated side the analyses of variance showed a significant subject effect but no significant masking level effect from 0 to 80 dB Sensation Level of masking. For the responses obtained from the masked side the same conclusions seem to apply. As contralateral masking has no adverse effect upon the BSER in normal subjects and has had considerable use on clinical patients, with no significant problem, the normal audiometric use of masking is recommended for BSER recording.
Topics: Adult; Auditory Pathways; Brain Stem; Dichotic Listening Tests; Evoked Potentials, Auditory; Female; Humans; Male; Perceptual Masking
PubMed: 6357324
DOI: 10.3109/03005368309107880