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CoDAS 2022To verify the test-retest reliability of the Masking Level Difference in normal hearing female university students.
PURPOSE
To verify the test-retest reliability of the Masking Level Difference in normal hearing female university students.
METHODS
Prospective descriptive study with 78 young female adults without hearing complaints, submitted to the compact disc version of the Masking Level Difference by Auditec of Saint Louis. The threshold was determined by the difference between signal-to-noise ratios at hearing thresholds found in the antiphasic and homophasic conditions. The test was applied by the same examiner in two moments (test and retest) with an interval of seven to 14 days between them. Inferential statistical analysis included comparison of test and retest situations using Student's t test for paired samples, calculation of the intraclass correlation coefficient and calculation of 95% confidence intervals for signal-to-noise ratios at hearing thresholds found in the antiphasic and homophasic conditions and for masking level difference.
RESULTS
The average signal-to-noise ratio at hearing threshold in the homophasic condition was -12.59 dB and -12.46 dB in the Test and Retest situations, respectively, and -21.54 dB and -21.08 dB in the antiphasic condition. The average value in the final Masking Level Difference result was 8.95 dB in the Test and 8.74 dB in the Retest. Intraclass correlation coefficient values obtained were 0.436, 0.625 and 0.577 for homophasic, antiphasic and Masking Level Difference conditions, respectively.
CONCLUSION
The Masking Level Difference showed moderate test-retest reliability in normal hearing adults female university students.
Topics: Adult; Auditory Threshold; Female; Hearing; Humans; Perceptual Masking; Prospective Studies; Reproducibility of Results; Students; Universities
PubMed: 35019083
DOI: 10.1590/2317-1782/20212020207 -
Perception Sep 2020According to the sequential surface integration process hypothesis, the fine near-ground-surface representation and the homogeneous ground surface play a vital role in...
According to the sequential surface integration process hypothesis, the fine near-ground-surface representation and the homogeneous ground surface play a vital role in the representation of the ground surface. When an occluding box or opaque wall is placed between observers and targets, observers underestimate egocentric distance. However, in our daily life, many obstacles are perforated and cover the ground surface and targets simultaneously (e.g., fences). Humans see and observe through fences. The images of these fences and targets, projected onto observers' retinas, overlap each other. This study aims to explore the effects of perforated obstacles (i.e., fences) on space perception. The results showed that observers underestimated the egocentric distances when there was a fence on the ground surface relative to the no-fence condition, and the effect of widely spaced thick wood fences was larger than that of narrowly spaced thin iron fences. We further demonstrated that this effect was quite robust when the target size had a visual angle of 1°, 2°, or 4° in three virtual reality experiments. This study may add support for the notion that the sequential surface integration process hypothesis is applicable even if the obstacle is perforated and covers the target.
Topics: Adult; Distance Perception; Female; Humans; Male; Perceptual Masking; Space Perception; Virtual Reality; Visual Perception; Young Adult
PubMed: 33002393
DOI: 10.1177/0301006620946525 -
Journal of Vision Oct 2021An object's processing is impaired by the presence of nearby clutter. Several distinct mechanisms, such as masking and visual crowding, are thought to contribute to such...
An object's processing is impaired by the presence of nearby clutter. Several distinct mechanisms, such as masking and visual crowding, are thought to contribute to such flanker-induced interference. It is therefore important to determine which mechanism is operational in any given situation. Previous studies have proposed that the in-out asymmetry (IOA), where a peripheral flanker interferes with the target more than a foveal flanker, is diagnostic of crowding. However, several studies have documented inconsistencies in the occurrence of this asymmetry, particularly at locations beyond the horizontal meridian, casting doubt on its ability to delineate crowding. In this study, to determine if IOA is diagnostic of crowding, we extensively charted its properties. We asked a relatively large set of participants (n = 38) to identify a briefly presented peripheral letter flanked by a single inward or outward letter at one of four locations. We also manipulated target location uncertainty and attentional allocation by blocking, randomizing or pre-cueing the target location. Using multilevel Bayesian regression analysis, we found robust IOA at all locations, although its strength was modulated by target location, location uncertainty, and attentional allocation. Our findings suggest that IOA can be an excellent marker of crowding, to the extent that it is not observed in other flanker-interference mechanisms, such as masking.
Topics: Attention; Bayes Theorem; Crowding; Humans; Pattern Recognition, Visual; Perceptual Masking; Visual Fields
PubMed: 34668932
DOI: 10.1167/jov.21.11.10 -
Journal of Vision Aug 2021Our conscious awareness of visual events does not arise instantaneously. Previous studies on backward masking have investigated dynamic internal processes making targets...
Our conscious awareness of visual events does not arise instantaneously. Previous studies on backward masking have investigated dynamic internal processes making targets visible or invisible subjectively. However, to understand the whole picture of our rich conscious experiences, the emergence of various phenomenal attributes of consciousness beyond visibility must be delineated. We quantified appearance as the strength of orientation repulsion during common-onset masking and found that masking reduced the repulsion in a near-vertical target grating surrounded by tilted inducers. Furthermore, this reduction was seen only when the inducers were presented together with or after the target. This demonstrates that orientation repulsion involves slow contextual modulation and that masking influences this modulation at a later period. Although appearance was altered as such, orientation discriminability was not reduced by masking in any of our experiments. We propose a process in which internal representations of objects spend a certain amount of time evolving before we become aware of them. Backward masking compulsorily terminates this temporal evolution of internal representations and allows premature representations to arise in our awareness.
Topics: Consciousness; Humans; Perceptual Masking; Photic Stimulation; Visual Perception
PubMed: 34342645
DOI: 10.1167/jov.21.8.5 -
Progress in Brain Research 2021The phenomenon of tinnitus masking (TM) and residual inhibition (RI) of tinnitus are two ways to investigate how external sounds interact with tinnitus: TM provides...
The phenomenon of tinnitus masking (TM) and residual inhibition (RI) of tinnitus are two ways to investigate how external sounds interact with tinnitus: TM provides insight on the fusion between external sound activity and tinnitus related activity while RI provides insight on how the external sound might suppress the tinnitus related activity for a period of time. Differences in masking level between the tinnitus and an external tone with tinnitus characteristics (frequency, loudness) have previously shown a high level of heterogeneity. The difference in poststimulus suppression between the two, that is, residual inhibition for the former, and forward masking for the latter, has never been explored. This study aims to investigate minimum masking levels (MMLs) and minimum residual inhibition levels (MRILs) of tinnitus and of an external tone mimicking tinnitus while using diotic and dichotic noises. Pulsed narrowband noises (1 octave width and centered at 1kHz, frequency of the hearing loss slope, tinnitus frequency) and white noise were randomly presented to 20 tinnitus participants and 20 controls with an external tone mimicking tinnitus (4kHz, intensity level corresponding to tinnitus loudness). The MML values obtained for the masking of tinnitus and for the mimicking external sounds were very similar. On the other hand, the MRILs were significantly different between the tinnitus and the mimicking external sounds within tinnitus participants. They were also different between the tinnitus participants and the controls. Overall, for both within and between comparisons, the MRIL values were much higher to produce a poststimulus suppression for the mimicking sound than for the tinnitus. The results showed no significant differences between the diotic and dichotic conditions. These results corroborate other findings suggesting that the tinnitus-related neural activity is very different from the stimulus-related neural activity. The consequences of this last finding are discussed.
Topics: Disease Progression; Humans; Inhibition, Psychological; Noise; Perceptual Masking; Tinnitus
PubMed: 33931182
DOI: 10.1016/bs.pbr.2020.08.010 -
Journal of Vision Nov 2019Stereoanomalous (SA) subjects have normal visual acuity but reduced stereopsis and may have a prevalence of up to 30%. It has been suggested that, in SA subjects, an...
Stereoanomalous (SA) subjects have normal visual acuity but reduced stereopsis and may have a prevalence of up to 30%. It has been suggested that, in SA subjects, an imbalance in interocular inhibition might underlie an asymmetry in sensory eye dominance (SED). Our study expands upon previous findings by examining binocular rivalry (BR) mean dominance durations, dichoptic masking (DM) thresholds and SED for a group of SA subjects compared to naïve controls. We examined BR dominance durations and DM thresholds for 15 stereonormal (SN) subjects and 10 SA subjects with normal or corrected-to-normal visual acuity. All subjects had visual acuity of 20/40 or better and less than or equal to two lines difference between eyes. Individuals who scored ≥6/9 on the Randot stereo test and <100 arcmin on the PacMan Stereo Acuity test were considered SN. We compared near-vertical and near-horizontal oriented sine-wave gratings for BR and DM in order to dissociate stereo-related mechanisms that rely on horizontal disparities from other eye-based integration mechanisms. Mean randot scores for SN subjects were 8.5/9 with a PacMan stereoacuity of 33 arcmin, and SA subjects scored 2.5/9 and 3,380 arcmin, respectively. The mean difference in SED was 0.19 for SN and 0.48 for SA when measured with a neutral density filter bar. The SA group showed a large interocular difference in BR durations that was significantly greater than normal (p = 0.004) and correlated with loss of stereoacuity. Moreover, the interocular difference for DM was similarly greater for SA subjects (p = 0.04) although a proportional difference in monocular sensitivity could partially account for this. We also found that both SN and SA subjects presented higher DM thresholds and, to some extent, sensitivity for vertical than horizontal orientations. SA subjects show an abnormal bias toward their dominant eye for both BR and DM. These data suggest that common mechanisms of monocular sensitivity and interocular inhibition may limit multiple binocular measures and provides a practical link to better understand the heterogeneity of stereopsis in amblyopia.
Topics: Adult; Depth Perception; Dominance, Ocular; Female; Humans; Male; Perceptual Disorders; Perceptual Masking; Vision, Binocular; Visual Acuity; Young Adult
PubMed: 31747692
DOI: 10.1167/19.13.14 -
The Journal of the Acoustical Society... Apr 2023The perception of amplitude modulations (AMs) has been characterized by a frequency-selective process in the temporal envelope domain and simulated in computational...
The perception of amplitude modulations (AMs) has been characterized by a frequency-selective process in the temporal envelope domain and simulated in computational auditory processing and perception models using a modulation filterbank. Such AM frequency-selective processing has been argued to be critical for the perception of complex sounds, including speech. This study aimed at investigating the effects of age on behavioral AM frequency selectivity in young (n = 11, 22-29 years) versus older (n = 10, 57-77 years) listeners with normal hearing, using a simultaneous AM masking paradigm with a sinusoidal carrier (2.8 kHz), target modulation frequencies of 4, 16, 64, and 128 Hz, and narrowband-noise modulation maskers. A reduction of AM frequency selectivity by a factor of up to 2 was found in the older listeners. While the observed AM selectivity co-varied with the unmasked AM detection sensitivity, the age-related broadening of the masked threshold patterns remained stable even when AM sensitivity was similar across groups for an extended stimulus duration. The results from the present study might provide a valuable basis for further investigations exploring the effects of age and reduced AM frequency selectivity on complex sound perception as well as the interaction of age and hearing impairment on AM processing and perception.
Topics: Humans; Auditory Threshold; Auditory Perception; Hearing; Noise; Hearing Loss; Perceptual Masking
PubMed: 37092934
DOI: 10.1121/10.0017835 -
Proceedings of the National Academy of... Jul 2021Recurrent loops in the visual cortex play a critical role in visual perception, which is likely not mediated by purely feed-forward pathways. However, the development of...
Recurrent loops in the visual cortex play a critical role in visual perception, which is likely not mediated by purely feed-forward pathways. However, the development of recurrent loops is poorly understood. The role of recurrent processing has been studied using visual backward masking, a perceptual phenomenon in which a visual stimulus is rendered invisible by a following mask, possibly because of the disruption of recurrent processing. Anatomical studies have reported that recurrent pathways are immature in early infancy. This raises the possibility that younger infants process visual information mainly in a feed-forward manner, and thus, they might be able to perceive visual stimuli that adults cannot see because of backward masking. Here, we show that infants under 7 mo of age are immune to visual backward masking and that masked stimuli remain visible to younger infants while older infants cannot perceive them. These results suggest that recurrent processing is immature in infants under 7 mo and that they are able to perceive objects even without recurrent processing. Our findings indicate that the algorithm for visual perception drastically changes in the second half of the first year of life.
Topics: Facial Recognition; Female; Form Perception; Humans; Infant; Male; Perceptual Masking; Photic Stimulation; Reproducibility of Results; Visual Perception
PubMed: 34162737
DOI: 10.1073/pnas.2103040118 -
Investigative Ophthalmology & Visual... Jun 2022We aimed to study the effect of stimulus contrast on the orientation selectivity of interocular interaction in amblyopia using a dichoptic masking paradigm.
PURPOSE
We aimed to study the effect of stimulus contrast on the orientation selectivity of interocular interaction in amblyopia using a dichoptic masking paradigm.
METHODS
Eight adults with anisometropic or mixed amblyopia and 10 control adults participated in our study. The contrast threshold in discriminating a target Gabor in the tested eye was measured with mean luminance in the untested eye, as well as with a bandpass oriented filtered noise in the other eye at low spatial frequency (0.25 c/d). Threshold elevation, which represents interocular suppression, was assessed using a the dichoptic masking paradigm (i.e. the contrast threshold difference between the target only and masked conditions), for each eye. Orientation selectivity of the interocular suppression as reflected by dichoptic masking was quantified by the difference between the parallel and orthogonal masking configurations. Two levels of mask's contrast (3 times or 10 times that of an individual's contrast threshold) were tested in this study.
RESULTS
The strength of dichoptic masking suppression was stronger at high, rather than low mask contrast in both amblyopic and control subjects. Normal controls showed orientation-dependent dichoptic masking suppression both under high and low contrast levels. However, amblyopes showed orientation-tuned dichoptic masking suppression only under the high contrast level, but untuned under the low contrast level.
CONCLUSIONS
We demonstrate that interocular suppression assessed by dichoptic masking is contrast-dependent in amblyopia, being orientation-tuned only at high suprathreshold contrast levels of the mask.
Topics: Adult; Amblyopia; Contrast Sensitivity; Humans; Perceptual Masking; Sensory Thresholds; Vision, Binocular
PubMed: 35675061
DOI: 10.1167/iovs.63.6.9 -
Attention, Perception & Psychophysics Apr 2022Categorization at different levels of abstraction have distinct time courses, but the different levels are often considered separately. Superordinate-level...
Categorization at different levels of abstraction have distinct time courses, but the different levels are often considered separately. Superordinate-level categorization is typically faster than basic-level categorization at ultra-rapid exposure durations (< 33 ms) while basic-level categorization is faster than superordinate-level categorization at longer exposure durations. This difference may be due to a competitive dynamic between levels of categorization. By leveraging object substitution masking, we found a distinct time course of masking effects for each level of categorization. Superordinate-level categorization showed a masking effect earlier than basic-level categorization. However, when basic-level categorization first showed a masking effects, superordinate-level categorization was spared despite its earlier masking effect. This unique pattern suggests a trade-off between the two levels of categorization over time. Such an effect supports an account of categorization that depends on the interaction of perceptual encoding, selective attention, and competition between levels of category representation.
Topics: Attention; Concept Formation; Humans; Pattern Recognition, Visual; Perceptual Masking; Reaction Time; Time Factors
PubMed: 35199323
DOI: 10.3758/s13414-022-02442-1