Investigating the auditory enhancement phenomenon using behavioral temporal masking patterns.
Ontology highlight
ABSTRACT:
SUBMITTER: Shen Y
PROVIDER: S-EPMC3505209 | biostudies-other | 2012 Nov
REPOSITORIES: biostudies-other
Similar Datasets
Project description:Self-recovery schemes identify and restore tampering, using as a reference a compressed representation of a signal embedded into itself. In addition, audio self-recovery must comply with a transparency threshold, adequate for applications such as on-line music distribution or speech transmission. In this manuscript, an audio self-recovery scheme is proposed. Auditory masking properties of the signals are used to determine the frequencies that better mask the embedding distortion. Frequencies in the Fourier domain are mapped to the intDCT domain for embedding and extraction of reference bits for signal restoration. The contribution of this work is the use of auditory masking properties for the frequency selection and the mapping to the intDCT domain. Experimental results demonstrate that the proposed scheme satisfies a threshold of -2 ODG, suitable for audio applications. The efficacy of the scheme, in terms of its restoration capabilities, is also shown.
| S-EPMC6161912 | biostudies-literature
Project description:Multisensory enhancement, as a facilitation phenomenon, is responsible for superior behavioral performance when an individual is responding to cross-modal versus modality-specific stimuli. However, the event-related potential (ERP) counterparts of behavioral multisensory enhancement are not well known. We recorded ERPs and behavioral data from 14 healthy volunteers with three types of target stimuli (modality-specific, bimodal, and trimodal) to examine the spatio-temporal electrophysiological characteristics of multisensory enhancement by comparing behavioral data with ERPs. We found a strong correlation between P3 latency and behavioral performance in terms of reaction time (RT) (R = 0.98, P <0.001), suggesting that P3 latency constitutes a temporal measure of behavioral multisensory enhancement. In addition, a fast RT and short P3 latency were found when comparing the modality-specific visual target with the modality-specific auditory and somatosensory targets. Our results indicate that behavioral multisensory enhancement can be identified by the latency and source distribution of the P3 component. These findings may advance our understanding of the neuronal mechanisms of multisensory enhancement.
| S-EPMC5562552 | biostudies-other
Project description:In human and animal auditory perception the perceived quality of sound streams changes depending on the duration of inter-sound intervals (ISIs). Here, we studied whether adaptation and the precision of temporal coding in the auditory periphery reproduce general perceptual boundaries in the time domain near 20, 100, and 400 ms ISIs, the physiological origin of which are unknown. In four experiments, we recorded auditory brainstem responses with five wave peaks (P1 -P5) in response to acoustic models of communication calls of house mice, who perceived these calls with the mentioned boundaries. The newly introduced measure of average standard deviations of wave latencies of individual animals indicate the waves' temporal precision (latency jitter) mostly in the range of 30-100 μs, very similar to latency jitter of single neurons. Adaptation effects of response latencies and latency jitter were measured for ISIs of 10-1000 ms. Adaptation decreased with increasing ISI duration following exponential or linear (on a logarithmic scale) functions in the range of up to about 200 ms ISIs. Adaptation effects were specific for each processing level in the auditory system. The perceptual boundaries near 20-30 and 100 ms ISIs were reflected in significant adaptation of latencies together with increases of latency jitter at P2-P5 for ISIs < ~30 ms and at P5 for ISIs < ~100 ms, respectively. Adaptation effects occurred when frequencies in a sound stream were within the same critical band. Ongoing low-frequency components/formants in a sound enhanced (decrease of latencies) coding of high-frequency components/formants when the frequencies concerned different critical bands. The results are discussed in the context of coding multi-harmonic sounds and stop-consonants-vowel pairs in the auditory brainstem. Furthermore, latency data at P1 (cochlea level) offer a reasonable value for the base-to-apex cochlear travel time in the mouse (0.342 ms) that has not been determined experimentally.
| S-EPMC6301773 | biostudies-literature
Project description:Recent studies of auditory streaming have suggested that repeated synchronous onsets and offsets over time, referred to as "temporal coherence," provide a strong grouping cue between acoustic components, even when they are spectrally remote. This study uses a measure of auditory stream formation, based on comodulation masking release (CMR), to assess the conditions under which a loss of temporal coherence across frequency can lead to auditory stream segregation. The measure relies on the assumption that the CMR, produced by flanking bands remote from the masker and target frequency, only occurs if the masking and flanking bands form part of the same perceptual stream. The masking and flanking bands consisted of sequences of narrowband noise bursts, and the temporal coherence between the masking and flanking bursts was manipulated in two ways: (a) By introducing a fixed temporal offset between the flanking and masking bands that varied from zero to 60 ms and (b) by presenting the flanking and masking bursts at different temporal rates, so that the asynchronies varied from burst to burst. The results showed reduced CMR in all conditions where the flanking and masking bands were temporally incoherent, in line with expectations of the temporal coherence hypothesis.
| S-EPMC4048442 | biostudies-other
Project description:The rapid advance of sequencing technology, coupled with improvements in molecular methods for obtaining genetic data from ancient sources, holds the promise of producing a wealth of genomic data from time-separated individuals. However, the population-genetic properties of time-structured samples have not been extensively explored. Here, we consider the implications of temporal sampling for analyses of genetic differentiation and use a temporal coalescent framework to show that complex historical events such as size reductions, population replacements, and transient genetic barriers between populations leave a footprint of genetic differentiation that can be traced through history using temporal samples. Our results emphasize explicit consideration of the temporal structure when making inferences and indicate that genomic data from ancient individuals will greatly increase our ability to reconstruct population history.
| S-EPMC4137715 | biostudies-literature
Project description:HYPOTHESIS:The hypothesis tested was that forward masking of the speech-evoked auditory brainstem response (sABR) increases peak latency as an inverse function of masker-signal interval (?t), and that the overall persistence of forward masking is age dependent. BACKGROUND:Older listeners exhibit deficits in forward masking. If forward-masked sABRs provide an objective measure of the susceptibility of speech sounds to prior stimulation, then this provides a novel approach to examining the age dependence of temporal processing. METHODS:A /da/ stimulus forward masked by speech-shaped noise (?t?=?4-64?ms) was used to measure sABRs in 10 younger and nine older participants. Forward masking of subsegments of the /da/ stimulus (?t?=?16?ms) and click trains (?t?=?0-64?ms) was also measured. RESULTS:Forward-masked sABRs from young participants showed an increase in latency with decreasing ?t for the initial peak. Latency shifts for later peaks were smaller and more uniform. None of the peak latencies returned to baseline by ?t?=?64?ms. Forward-masked /da/ subsegments showed peak latency shifts that did not depend simply on peak position, while forward-masked click trains showed latency shifts that were dependent on click position. The sABRs from older adults were less robust but confirmed the viability of the approach. CONCLUSION:Forward masking of the sABR provides an objective measure of the susceptibility of the auditory system to prior stimulation. Failure of recovery functions to return to baseline suggests an interaction between forward masking by the prior masker and temporal effects within the stimulus itself.
| S-EPMC5823537 | biostudies-literature
Project description:Our ability to detect target sounds in complex acoustic backgrounds is often limited not by the ear's resolution, but by the brain's information-processing capacity. The neural mechanisms and loci of this "informational masking" are unknown. We combined magnetoencephalography with simultaneous behavioral measures in humans to investigate neural correlates of informational masking and auditory perceptual awareness in the auditory cortex. Cortical responses were sorted according to whether or not target sounds were detected by the listener in a complex, randomly varying multi-tone background known to produce informational masking. Detected target sounds elicited a prominent, long-latency response (50-250 ms), whereas undetected targets did not. In contrast, both detected and undetected targets produced equally robust auditory middle-latency, steady-state responses, presumably from the primary auditory cortex. These findings indicate that neural correlates of auditory awareness in informational masking emerge between early and late stages of processing within the auditory cortex.
| S-EPMC2422852 | biostudies-literature
Project description:Slum rehabilitation policies in India is observed to have a rebound effect on the occupants, where rehabilitated occupants move back to the horizontal slums. In this study, we investigate the cause behind this rebound phenomenon based on a theory of homeostasis, where the loss of homeostasis refers to occupants' heightened discomfort and distress in their built environment. A novel methodological framework was developed to investigate it based on the principles of participatory backcasting approach and the theory of homeostasis. Thirty households in Mumbai's slum rehabilitation housing were interviewed to determine the social, economic and environmental cause of distress and discomfort. Granular information was obtained by further investigating the factors that influence occupants' attitude, emotions, health, control and habits in their built environment that regulates their holistic comfort and lack of stress. The causal linkages among these factors were established using a qualitative fault tree. Results show two primary cause of distress and discomfort in the study area owing to economic distress and built environment related discomfort. Economic distress was from low-income and high electricity bills due to higher household appliance ownership, and built environment discomfort was due to lack of social spaces and poor design of the slum rehabilitation housing. This study showed that mitigating such non-income drivers of distress and discomfort can prevent rebound phenomenon and improve the sustainability of the slum rehabilitation process.
| S-EPMC6559131 | biostudies-literature
Project description:Auditory streaming is the process by which environmental sound is segregated into discrete perceptual objects. The auditory system has a remarkable capability in this regard as revealed in psychophysical experiments in humans and other primates. However, little is known about the underlying neuronal mechanisms, in part because of the lack of suitable behavioural paradigms in non-primate species. The mouse is an increasingly popular model for studying the neural mechanisms of perception and action because of the range of molecular tools enabling precise manipulation of neural circuitry. Here we present a novel behavioural task that can be used to assess perceptual aspects of auditory streaming in head-fixed mice. Animals were trained to detect a target sound in a one of two simultaneously presented, isochronous pure tone sequences. Temporal expectation was manipulated by presenting the target sound in a particular stream either early (~2 s) or late (~4 s) with respect to trial onset in blocks of 25-30 trials. Animals reached high performance on this task (d' > 1 overall), and notably their false alarms were very instructive of their behavioural state. Indeed, false alarm timing was markedly delayed for late blocks compared to early ones, indicating that the animals associated a different context to an otherwise identical stimulus. More finely, we observed that the false alarms were timed to the onset of the sounds present in the target stream. This suggests that the animals could selectively follow the target stream despite the presence of a distractor stream. Extracellular electrophysiological recordings during the task revealed that sound processing is flexibly modulated in a manner consistent with the optimisation of behavioural outcome. Together, these results indicate that the perceptual streaming can be inferred via the timing of false alarms in mice, and provide a new paradigm with which to investigate neuronal mechanisms of selective attention.
| S-EPMC6141755 | biostudies-literature
Project description:The causes of seasonal variability in pathogen transmission are not well understood, and have not been comprehensively investigated. In an example for enteric pathogens, incidence of Escherichia coli O157 (STEC) colonization in cattle is consistently higher during warmer months compared to cooler months in various cattle production systems. However, actual mechanisms for this seasonality remain elusive. In addition, the influence of host (cattle) behavior on this pattern has not been thoroughly considered. To that end, we constructed a spatially explicit agent-based model that accounted for the effect of temperature fluctuations on cattle behavior (direct contact among cattle and indirect between cattle and environment), as well as its effect on pathogen survival in the environment. We then simulated the model in a factorial approach to evaluate the hypothesis that temperature fluctuations can lead to seasonal STEC transmission dynamics by influencing cattle aggregation, grazing, and drinking behaviors. Simulation results showed that higher temperatures increased the frequency at which cattle aggregated under shade in pasture, resulting in increased direct contact and transmission of STEC between individual cattle, and hence higher incidence over model simulations in the warm season. In contrast, increased drinking behavior during warm season was not an important transmission pathway. Although sensitivity analyses suggested that the relative importance of direct vs. indirect (environmental) pathways depend to upon model parameterization, model simulations indicated that factors influencing cattle aggregation, such as temperature, were likely strong drivers of transmission dynamics of enteric pathogens.
| S-EPMC6179278 | biostudies-literature