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Introduction: Past studies have provided evidence that the effects of tactile stimulation on binocular rivalry are mediated by primitive features (orientation and spatial frequency) common in vision and touch. In this study, we examined whether such effects on binocular rivalry can be obtained through the roughness of naturalistic objects. In three experiments, the total dominant time of visual percepts of two objects was measured under binocular rivalry when participants touched one of the objects. Result: In Experiment 1, the total dominant time for the image of artificial turf and bathmat was prolonged by congruent tactile stimulation and shortened by incongruent tactile stimulation. In Experiment 2, we used the same stimuli but rotated their visual images in opposite directions. The dominant time for either image was prolonged by congruent tactile stimulation. In Experiment 3, we used different types of stimuli, smooth marble and rough fabric, and noted significant effects of the congruent and incongruent tactile stimulation on the dominant time of visual percepts. Conclusions: These three experiments demonstrated that visuo-tactile interaction on binocular rivalry can be mediated by roughness.

In an attempt to develop tests of auditory temporal resolution using gap detection, we conducted computer simulations of Zippy Estimation by Sequential Testing (ZEST), an adaptive Bayesian threshold estimation procedure, for measuring gap detection thresholds. The results showed that the measures of efficiency and precision of ZEST changed with the mean and standard deviation (SD) of the initial probability density function implemented in ZEST. Appropriate combinations of mean and SD values led to efficient ZEST performance; i.e., the threshold estimates converged to their true values after 10 to 15 trials. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to investigate whether speech perception would reflect small latency changes in subcortical speech representation. Method: Twelve native Japanese listeners participated in the experiment. Those listeners participated in speech identification task and auditory brainstem response (ABR) measurement using /d/--/t/ continuum stimuli varying in voice onset time (VOT) with manipulation of the amplitude of initial noise (consonant) portion, the duration of which corresponded to VOT. Results: Increasing the noise portion amplitude lengthened subcortical representation of VOT, which is the latency difference between ABRs synchronizing to the onsets of initial noise and following periodic (vowel) portions (VOT ABR) and made listeners likely to perceive the stimuli with ambiguous VOT as a voiceless stop /t/. In addition, the amount of VOT ABR lengthening was close to that of the VOT boundary shortening. Conclusion: A few milliseconds of difference in subcortical speech representation are important for the perception of speech sounds with ambiguous acoustic cues.

We previously found that ribosomal protein L9 (RPL9) is a novel advanced glycation end product (AGE)‐binding protein that can decrease pro‐inflammatory TNF‐α expression stimulated by lipopolysaccharide (LPS) plus high‐mobility group box 1 (HMGB1), suggesting that RPL9 has a role in regulating LPS+HMGB1‐stimulated inflammatory reactions. Among the various ribosomal proteins, it was found that RPS5 reproduced the regulatory activity of RPL9 on LPS+HMGB1‐stimulated TNF‐α expression in macrophage‐like RAW264.7 cells. RPL9 and RPS5 share a common feature as cationic proteins. Polylysine, a cationic polypeptide, and a synthetic peptide of the cationic region from RPL9 also exhibited reducing activity on LPS+HMGB1‐induced TNF‐α expression. By pull‐down assay, RPL9 and RPS5 were confirmed to interact with AGEs. When AGEs coexisted with LPS, HMGB1, plus RPL9 or RPS5, the reducing effect of TNF‐α expression by these cationic ribosomal proteins was shown to be abrogated. The results suggest that cationic ribosomal proteins have a regulatory role in the pro‐inflammatory response induced by LPS+HMGB1, and in the pathophysiological condition of accumulating AGEs, this regulatory effect is abolished, which exacerbates inflammation. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to investigate the psychophysical boundary used for categorization of voiced-voiceless stop consonants in native Japanese speakers. Method: Twelve native Japanese speakers participated in the experiment. The stimuli were synthetic stop consonant-vowel stimuli varying in voice onset time (VOT) with manipulation of the amplitude of the initial noise portion and the first formant (F1) frequency of the periodic portion. There were 3 tasks, namely, speech identification to either /d/ or /t/, detection of the noise portion, and simultaneity judgment of onsets of the noise and periodic portions. Results: The VOT boundaries of /d/-/t/ were close to the shortest VOT values that allowed for detection of the noise portion but not to those for perceived nonsimultaneity of the noise and periodic portions. The slopes of noise detection functions along VOT were as sharp as those of voiced-voiceless identification functions. In addition, the effects of manipulating the amplitude of the noise portion and the F1 frequency of the periodic portion on the detection of the noise portion were similar to those on voiced-voiceless identification. Conclusion: The psychophysical boundary of perception of the initial noise portion masked by the following periodic portion may be used for voiced-voiceless categorization by Japanese speakers.

Purpose: The purpose of this study was to investigate whether speech perception would reflect small latency changes in subcortical speech representation. Method: Twelve native Japanese listeners participated in the experiment. Those listeners participated in speech identification task and auditory brainstem response (ABR) measurement using /d/-/t/ continuum stimuli varying in voice onset time (VOT) with manipulation of the amplitude of initial noise (consonant) portion, the duration of which corresponded to VOT. Results: Increasing the noise portion amplitude lengthened subcortical representation of VOT, which is the latency difference between ABRs synchronizing to the onsets of initial noise and following periodic (vowel) portions ([VOT.sub.ABR]) and made listeners likely to perceive the stimuli with ambiguous VOT as a voiceless stop /t/. In addition, the amount of [VOT.sub.ABR] lengthening was close to that of the VOT boundary shortening. Conclusion: A few milliseconds of difference in subcortical speech representation are important for the perception of speech sounds with ambiguous acoustic cues. Supplemental Material: https://doi.org/10.23641/asha. 7728695, Neural representation of speech sounds in the auditory pathways of humans and animals has been studied for many years (Steinschneider, Nourski, & Fishman, 2013; Young, 2008). In recent years, many [...]

Purpose: The purpose of this study was to investigate the psychophysical boundary used for categorization of voiced-voiceless stop consonants in native Japanese speakers. Method: Twelve native Japanese speakers participated in the experiment. The stimuli were synthetic stop consonant-vowel stimuli varying in voice onset time (VOT) with manipulation of the amplitude of the initial noise portion and the first formant (F1) frequency of the periodic portion. There were 3 tasks, namely, speech identification to either /d/ or /t/, detection of the noise portion, and simultaneity judgment of onsets of the noise and periodic portions. Results: The VOT boundaries of /d/-/t/ were close to the shortest VOT values that allowed for detection of the noise portion but not to those for perceived nonsimultaneity of the noise and periodic portions. The slopes of noise detection functions along VOT were as sharp as those of voiced-voiceless identification functions. In addition, the effects of manipulating the amplitude of the noise portion and the F1 frequency of the periodic portion on the detection of the noise portion were similar to those on voiced-voiceless identification. Conclusion: The psychophysical boundary of perception of the initial noise portion masked by the following periodic portion may be used for voiced-voiceless categorization by Japanese speakers., A fundamental property of speech perception is to map highly variable acoustic sounds to discrete phonetic categories (Diehl, Lotto, & Holt, 2004; Liberman, Cooper, Shankweiler, & Studdert-Kennedy, 1967). However, the [...]