The gap transfer illusion is an auditory phenomenon in which a temporal gap in a longer glide transfers perceptually to a crossing shorter glide, making the longer glide illusorily continuous. This continuity is often considered a variation of classic illusory auditory continuity attributed to auditory peripheral activity, but a new view is given here supported by a series of sound demonstrations indicating that this illusory continuity is purely caused by a higher mechanism of perceptual organization.
View Article and Find Full Text PDFThe gap transfer illusion is an auditory illusion in which a temporal gap in a long glide is perceived as if it had transferred to a physically continuous shorter glide. The illusion typically occurs when the long and the shorter glide cross each other at their temporal midpoints, where the long glide is physically divided by the gap. The occurrence of the gap transfer illusion was investigated in stimuli in which the duration and the slope of the long glide were 5000 ms and ∼0.
View Article and Find Full Text PDFThe purpose of this study was to investigate how the subjective impression of English speech would change when pause duration at punctuation marks was varied. Two listening experiments were performed in which written English speech segments were rated on a variety of evaluation items by both native-English speakers and non-native speakers (native-Chinese speakers and native-Japanese speakers). The ratings were then subjected to factor analysis.
View Article and Find Full Text PDFThe present investigation focused on how temporal degradation affected intelligibility in two types of languages, i.e., a tonal language (Mandarin Chinese) and a non-tonal language (Japanese).
View Article and Find Full Text PDFExperiments that focus on how humans perceive temporal, spatial or synaesthetic congruency in audiovisual sensory information have often employed stimuli consisting of a Gabor patch and an amplitude (AM) or frequency (FM)-modulated sound. Introducing similarity between the static and dynamic features of the Gabor patch and the (carrier) frequency or modulation frequency of the sound is often assumed to be effective enough to induce congruency. However, comparative empirical data on perceived congruency of various stimulus parameters are not readily available, and in particular with respect to sound modulation, it is still not clear which type (AM or FM) induces perceived congruency best in tandem with various patch parameters.
View Article and Find Full Text PDFTo create a self-motion (vection) situation in three-dimensional computer graphics (CG), there are mainly two ways: moving a camera toward an object ("camera moving") or by moving the object and its surrounding environment toward the camera ("object moving"). As both methods vary considerably in the amount of computer calculations involved in generating CG, knowing how each method affects self-motion perception should be important to CG-creators and psychologists. Here, we simulated self-motion in a virtual three-dimensional CG-world, without stereoscopic disparity, which correctly reflected the lighting and glare.
View Article and Find Full Text PDFAuditory icons are short sound messages that convey information about an object, event or situation. Originally, auditory icons have been used in computer interfaces, but are nowadays found in many other fields. In this review article, an overview is given of the main theoretical ideas behind the use and design of auditory icons.
View Article and Find Full Text PDFWhen the objects in a typical stream-bounce stimulus are made to rotate on a circular trajectory, not two but four percepts can be observed: streaming, bouncing, clockwise rotation, and counterclockwise rotation, often with spontaneous reversals between them. When streaming or bouncing is perceived, the objects seem to move on individual, opposite trajectories. When rotation is perceived, however, the objects seem to move in unison on the same circular trajectory, as if constituting the edges of a virtual pane that pivots around its axis.
View Article and Find Full Text PDFTemporal resolution needed for Japanese speech communication was measured. A new experimental paradigm that can reflect the spectro-temporal resolution necessary for healthy listeners to perceive speech is introduced. As a first step, we report listeners' intelligibility scores of Japanese speech with a systematically degraded temporal resolution, so-called "mosaic speech": speech mosaicized in the coordinates of time and frequency.
View Article and Find Full Text PDFThe inferior frontal and superior temporal areas in the left hemisphere are crucial for human language processing. In the present study, we investigated the magnetic mismatch field (MMF) evoked by voice stimuli in 3- to 5-year-old typically developing (TD) children and children with autism spectrum disorder (ASD) using child-customized magnetoencephalography (MEG). The children with ASD exhibited significantly decreased activation in the left superior temporal gyrus compared with the TD children for the MMF amplitude.
View Article and Find Full Text PDFPurpose: The purpose of this study was to assess cortical hemodynamic response patterns in 3- to 7-year-old children listening to two speech modes: normally vocalized and whispered speech. Understanding whispered speech requires processing of the relatively weak, noisy signal, as well as the cognitive ability to understand the speaker's reason for whispering.
Method: Near-infrared spectroscopy (NIRS) was used to assess changes in cortical oxygenated hemoglobin from 16 typically developing children.
The auditory-evoked P1m, recorded by magnetoencephalography, reflects a central auditory processing ability in human children. One recent study revealed that asynchrony of P1m between the right and left hemispheres reflected a central auditory processing disorder (i.e.
View Article and Find Full Text PDFFactor analysis (principal component analysis followed by varimax rotation) had shown that 3 common factors appear across 20 critical-band power fluctuations derived from spoken sentences of eight different languages [Ueda et al. (2010). Fechner Day 2010, Padua].
View Article and Find Full Text PDFExpectancy for an upcoming musical chord, harmonic expectancy, is supposedly based on automatic activation of tonal knowledge. Since previous studies implicitly relied on interpretations based on Western music theory, the underlying computational processes involved in harmonic expectancy and how it relates to tonality need further clarification. In particular, short chord sequences which cannot lead to unique keys are difficult to interpret in music theory.
View Article and Find Full Text PDFThe P1m component of the auditory evoked magnetic field is the earliest cortical response associated with language acquisition. However, the growth curve of the P1m component is unknown in both typically developing (TD) and atypically developing children. The aim of this study is to clarify the developmental pattern of this component when evoked by binaural human voice stimulation using child-customized magnetoencephalography.
View Article and Find Full Text PDFThe relationship between language development in early childhood and the maturation of brain functions related to the human voice remains unclear. Because the development of the auditory system likely correlates with language development in young children, we investigated the relationship between the auditory evoked field (AEF) and language development using non-invasive child-customized magnetoencephalography (MEG) in a longitudinal design. Twenty typically developing children were recruited (aged 36-75 months old at the first measurement).
View Article and Find Full Text PDFA child-customized magnetoencephalography system was used to investigate somatosensory evoked field (SEF) in 3- to 4-year-old children. Three stimulus conditions were used in which the children received tactile-only stimulation to their left index finger or visuotactile stimulation. In the two visuotactile conditions, the children received tactile stimulation to their finger while they watched a video of tactile stimulation applied either to someone else's finger (the finger-touch condition) or to someone else's toe (the toe-touch condition).
View Article and Find Full Text PDFOptimal brain sensitivity to the fundamental frequency (F0) contour changes in the human voice is important for understanding a speaker's intonation, and consequently, the speaker's attitude. However, whether sensitivity in the brain's response to a human voice F0 contour change varies with an interaction between an individual's traits (i.e.
View Article and Find Full Text PDFAutism spectrum disorder (ASD) is often described as a disorder of aberrant neural connectivity and/or aberrant hemispheric lateralization. Although it is important to study the pathophysiology of the developing ASD cortex, the physiological connectivity of the brain in young children with ASD under conscious conditions has not yet been described. Magnetoencephalography (MEG) is a noninvasive brain imaging technique that is practical for use in young children.
View Article and Find Full Text PDFBackground: Magnetoencephalography (MEG) is used to measure the auditory evoked magnetic field (AEF), which reflects language-related performance. In young children, however, the simultaneous quantification of the bilateral auditory-evoked response during binaural hearing is difficult using conventional adult-sized MEG systems. Recently, a child-customised MEG device has facilitated the acquisition of bi-hemispheric recordings, even in young children.
View Article and Find Full Text PDFSocio-communicative impairments are salient features of autism spectrum disorder (ASD) from a young age. The anterior prefrontal cortex (aPFC), or Brodmann area 10, is a key processing area for social function, and atypical development of this area is thought to play a role in the social deficits in ASD. It is important to understand these brain functions in developing children with ASD.
View Article and Find Full Text PDFA subset of individuals with autism spectrum disorder (ASD) performs more proficiently on certain visual tasks than may be predicted by their general cognitive performances. However, in younger children with ASD (aged 5 to 7), preserved ability in these tasks and the neurophysiological correlates of their ability are not well documented. In the present study, we used a custom child-sized magnetoencephalography system and demonstrated that preserved ability in the visual reasoning task was associated with rightward lateralisation of the neurophysiological connectivity between the parietal and temporal regions in children with ASD.
View Article and Find Full Text PDFAccurate perception of fundamental frequency (F0) contour changes in the human voice is important for understanding a speaker's intonation, and consequently also his/her attitude. In this study, we investigated the neural processes involved in the perception of F0 contour changes in the Japanese one-syllable interjection "ne" in 21 native-Japanese listeners. A passive oddball paradigm was applied in which "ne" with a high falling F0 contour, used when urging a reaction from the listener, was randomly presented as a rare deviant among a frequent "ne" syllable with a flat F0 contour (i.
View Article and Find Full Text PDFLanguage development progresses at a dramatic rate in preschool children. As rapid temporal processing of speech signals is important in daily colloquial environments, we performed magnetoencephalography (MEG) to investigate the linkage between speech-evoked responses during rapid-rate stimulus presentation (interstimulus interval < 1 s) and language performance in 2- to 5-year-old children (n = 59). Our results indicated that syllables with this short stimulus interval evoked detectable P50m, but not N100m, in most participants, indicating a marked influence of longer neuronal refractory period for stimulation.
View Article and Find Full Text PDFRecent neuroimaging studies support the view that a left-lateralized brain network is crucial for language development in children. However, no previous studies have demonstrated a clear link between lateralized brain functional network and language performance in preschool children. Magnetoencephalography (MEG) is a noninvasive brain imaging technique and is a practical neuroimaging method for use in young children.
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