Publications by authors named "Shui' er Han"

Binocular rivalry is a fascinating, widely studied visual phenomenon in which perception alternates between two competing images. This experience, however, is generally restricted to laboratory settings where two irreconcilable images are presented separately to the two eyes, an implausible geometry where two objects occupy the same physical location. Such laboratory experiences are in stark contrast to everyday visual behavior, where rivalry is almost never encountered, casting doubt on whether rivalry is relevant to our understanding of everyday binocular vision.

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Recent head-mounted displays and smart glasses use vision multiplexing, an optical approach where two or more views are superimposed on each other. In vision multiplexing, augmented information is presented over an observer's natural field of view, providing field expansion and critical information during mobility situations like walking and driving. Yet despite its utility, vision multiplexing may produce visual rivalry, a phenomenon where perception alternates between the augmented information and the background scene for seconds at a time.

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Article Synopsis
  • Visual confusion arises when different images are overlaid on the same part of the retina, useful in wearable displays to present multiple data sources, but can lead to visual rivalry that suppresses one image.
  • The study examined how visual rivalries affect the visibility of peripheral targets using different display types (monocular opaque, monocular see-through, and binocular see-through) and varied eye movement conditions (saccades, smooth pursuit, and central fixation).
  • Results indicated that binocular displays enhanced target visibility significantly compared to monocular ones, with the monocular see-through display offering the least visibility; eye movements also helped increase visibility by mitigating rivalry effects.
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Through development, multisensory systems reach a balance between stability and flexibility: the systems integrate optimally cross-modal signals from the same events, while remaining adaptive to environmental changes. Is continuous intersensory recalibration required to shape optimal integration mechanisms, or does multisensory integration develop prior to recalibration? Here, we examined the development of multisensory integration and rapid recalibration in the temporal domain by re-analyzing published datasets for audio-visual, audio-tactile, and visual-tactile combinations. Results showed that children reach an adult level of precision in audio-visual simultaneity perception and show the first sign of rapid recalibration at 9 years of age.

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Continuous flash suppression (CFS) is a popular masking technique used to manipulate visual awareness. By presenting a rapidly changing stimulus to one eye (the 'mask'), a static image viewed by the other (the 'target') may remain invisible for many seconds. This effectiveness affords a means to assess unconscious visual processing, leading to the widespread use of CFS in several basic and clinical sciences.

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Short-term deprivation (2.5 h) of an eye has been shown to boost its relative ocular dominance in young adults. Here, we show that a much shorter deprivation period (3-6 min) produces a similar paradoxical boost that is retinotopic and reduces spatial inhibition on neighbouring, non-deprived areas.

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In continuous flash suppression (CFS), an image presented to one eye is suppressed from awareness by a dynamic image masker presented to the other eye. Previous studies report that face stimuli break out of CFS more readily when they are oriented upright and contain ecologically relevant information such as facial expressions or direct eye gaze, potentially implicating face processing in the mechanisms of interocular competition. It is unknown, however, whether face content helps to drive interocular suppression when incorporated into the dynamic masker itself, either by engaging higher-level visual mechanisms that underlie face detection or due to lower-level image features that the faces happen to contain.

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Continuous flash suppression (CFS) is a technique in which presenting one eye with a dynamic Mondrian sequence prevents a low-contrast target in the other eye from being perceived for many seconds. Frequently used to study unconscious visual processing, CFS bears many similarities with binocular rivalry (BR), another popular dichoptic stimulation technique. It is therefore puzzling that the effect of mask size and contrast seem to differ between CFS and BR.

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In continuous flash suppression (CFS), a dynamic sequence of Mondrian patterns presented to one eye suppresses a static target in the other eye for several seconds at a time. Its effectiveness has been linked to low-level properties such as spatial frequency and orientation, but the role of higher order influences remains unstudied. Here, using a tracking paradigm, we asked if the spatial and temporal predictability of the Mondrian sequence affects CFS dynamics.

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Objective: Evaluations of vision prostheses and sensory substitution devices have frequently relied on repeated training and then testing with the same small set of items. These multiple forced-choice tasks produced above chance performance in blind users, but it is unclear if the observed performance represents restoration of vision that transfers to novel, untrained items.

Approach: Here, we tested the generalizability of the forced-choice paradigm on discrimination of low-resolution word images.

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Continuous flash suppression (CFS) is a popular technique whereby a dynamic sequence of Mondrian patterns is presented to one eye in order to suppress a static target presented to the other eye. Although the effectiveness of CFS is generally assumed to increase with the flicker rate of the Mondrian masker, a recent study has shown that suppression is optimal at very low masker rates for sustained targets, but higher rates may be necessary for transient targets. Here we vary the modulation rates of the masker and target using temporally filtered dynamic noise, which allowed us to examine the relationship between target and masker frequency and its effect on suppression strength.

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Continuous flash suppression (CFS) involves the presentation of a rapidly changing Mondrian sequence to one eye and a static target in the other eye. Targets presented in this manner remain suppressed for several seconds at a time, and this has seen the prevalent use of CFS in studies of unconscious visual processes. However, the mechanisms behind CFS remain unclear, complicating its use and the comprehension of results obtained with the paradigm.

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Sustained exposure to an asynchronous multisensory signal causes perceived simultaneity to shift in the direction of the leading component of the adapting stimulus. This is known as temporal recalibration, and recent evidence suggests that it can occur very rapidly, even after a single asynchronous audiovisual (AV) stimulus. However, this form of rapid recalibration appears to be unique to AV stimuli, in contrast to recalibration following sustained asynchronies which occurs with audiotactile (AT) and visuotactile (VT) stimuli.

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Continuous flash suppression (CFS) is a psychophysical technique where a rapidly changing Mondrian pattern viewed by one eye suppresses the target in the other eye for several seconds. Despite the widespread use of CFS to study unconscious visual processes, the temporal tuning of CFS suppression is currently unknown. In the present study we used spatiotemporally filtered dynamic noise as masking stimuli to probe the temporal characteristics of CFS.

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Audition--what listeners hear--is generally studied in terms of the physical properties of sound stimuli and physiological properties of the auditory system. Based on recent work in vision, we here consider an alternative perspective that sensory percepts are based on past experience. In this framework, basic auditory qualities (e.

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In Western music, the major mode is typically used to convey excited, happy, bright or martial emotions, whereas the minor mode typically conveys subdued, sad or dark emotions. Recent studies indicate that the differences between these modes parallel differences between the prosodic and spectral characteristics of voiced speech sounds uttered in corresponding emotional states. Here we ask whether tonality and emotion are similarly linked in an Eastern musical tradition.

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Whereas the use of discrete pitch intervals is characteristic of most musical traditions, the size of the intervals and the way in which they are used is culturally specific. Here we examine the hypothesis that these differences arise because of a link between the tonal characteristics of a culture's music and its speech. We tested this idea by comparing pitch intervals in the traditional music of three tone language cultures (Chinese, Thai and Vietnamese) and three non-tone language cultures (American, French and German) with pitch intervals between voiced speech segments.

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