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..e., 40 ms). Possible explanations for this duration-dependent age-related decline in concurrent sound perception are a general slowing in auditory processing and/or lengthening of the temporal integration window...

..The results reveal that inharmonicity is rapidly and automatically registered in all three age groups but that the perception of concurrent sounds declines with age...

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..These findings also suggest that processes involved in distinguishing concurrent auditory objects continue to mature during adolescence...

..However, this age-related decline in automatic detection of small change in the auditor environment can be compensated for by top-down controlled processes...

..The results show that for identical sounds, top-down effects on processing "what" and "where" information is observable at about 200 ms after sound onset and involves a widely distributed neural network...

..e., sequential vs. simultaneous grouping processes), and that they each recruit distinct neural networks...

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..The notion of auditory scene analysis is used as a conceptual framework for interpreting and studying the perception of sound...

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..Importantly, the neuroplastic changes occurred rapidly, demonstrating the flexibility of human speech segregation mechanisms...

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..Most findings can be accounted for by an object-based hypothesis in which auditory attention is allocated to perceptual objects derived from the auditory scene according to perceptual grouping principles...

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..The fact that both performance and P3b amplitude were similar in patients and controls suggests that controlled processes compensate for processes normally carried out by early perceptual mechanisms...

..The results suggest separate memory-related processing for auditory frequency and patterns and indicate that the neural circuit of deviance detection varies as a function of the perceptual context...

..These findings are analogous to the "what" and "where" segregation of visual information processing, and suggest that a similar functional organization exists for processing information from the auditory modality...

..Brain electrical source analyses showed that distinguishing simultaneous auditory objects involved a widely distributed neural network that included auditory cortices, the medial temporal lobe, and posterior association cortices...

..Hippocampal lesions did not affect either performance or electrophysiological measures. The results provide evidence of a temporal-prefrontal neocortical network critical for the transient storage of auditory stimuli...

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..These findings provide neuro-physiological evidence indicating that deficits in error monitoring in schizophrenia arise from a disruption of error-detection processes, possibly attributable to anterior cingulate dysfunction...

..The results are consistent with a top-down nonspecific attention effect on neural activity during learning as well as a more learning-specific modulation, which is coincident with behavioral improvements in speech identification...

..The results are consistent with an age-related decline in parsing simultaneous auditory events, which may contribute to the speech perception difficulties in the elderly...

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..These results provide evidence for the existence of altered neural processes associated with conflict processing that may be associated with dysfunction of the anterior cingulate and prefrontal cortex in patients with schizophrenia...

..In Experiment 3, we investigated auditory ERP generation under conditions of no visual task. The results are discussed with respect to a distinction between process-general (N1 and P2) and process-specific (MMN and ORN) auditory ERPs...

..The results show that selective attention modulates auditory pattern memory...

..The radial contribution is expressed preferentially in EEG, highlighting the importance of combining EEG with MEG where complex source configurations are suspected...

..Improvements in the techniques for measuring the MMN and in the paradigms for eliciting it will be needed before the MMN can become clinically useful as an objective measurement of such disorders in individual patients...

..These findings support the notion that attentional capture with peripheral cues is not simply reflexive but is modulated by top-down processes...

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..Topographic maps of acoustic attributes, stimulus-specific suppression, and competition between representations are among the neurophysiological mechanisms that likely contribute to streaming. A framework for future research is proposed...

..The analyses also suggested the possibility of additional sources in the frontal lobes...

..The neural correlates of inhibitory deficits for emotional semantic material in persons with major depressive disorder (MDD) were investigated...

..The results demonstrate that the N1 and P2 waves can resolve duration differences as short as 2-4 ms and that normal aging decreases the temporal resolving power for processing small differences in sound duration...

..These findings provide evidence for two cortical mechanisms of streaming: automatic segregation of sounds and attention-dependent buildup process that integrates successive tones within streams over several seconds...

..Our data suggest that any such processing is in fact preceded by activation in primary auditory cortex...

..The results also indicate that a conjunction of harmonicity and location cues contribute to sound segregation primarily when harmonicity is ambiguous...

..e., gap) within and between channels is comparable despite significant differences in gap size. The dipole source modeling suggests that both within- and between-gap signals are represented in or near the primary auditory cortex...

..Perceptual discrimination is related to interactions between the frontal and temporal regions, stimulus-response association occurs in the temporo-parietal regions and post-perceptual processing in the right temporo-parietal region...

..The data are discussed in terms of current models of concurrent sound perception and how top-down processes might influence these mechanisms...

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..We conclude that age-related difficulties in separating competing speakers are unlikely to arise from deficits in streaming and might instead reflect less efficient concurrent sound segregation...

..The early latency of MMN for changes in sound location is interpreted in the context of an early-warning system to alert the organism to new sound sources in the environment...

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..Other deficits, including TCC and CC, may be required for spontaneous confabulations to arise. The confluence of different sub-components of strategic retrieval would determine the content of confabulation and exacerbate its occurrence...

..We suggest that noise-induced increases in transient evoked responses may be mediated via efferent feedback connections between the auditory cortex and lower auditory centers...

..In contrast, young and older adults showed a similar pattern of neural activity indexing attentive processing of Deltaf0. The results suggest that aging affects the ability to automatically segregate speech sounds...

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..These results suggest that the auditory AB reflects a limitation of short-term consolidation and provides evidence for a common underlying processing limitation during the AB in both visual and auditory modalities...

..The observed effects indicate that age-related changes in auditory acuity have more to do with higher-order brain functions than previously thought...

..The results are consistent with a spotlight model of auditory attention in which the processing of stimuli outside the attentional focus is attenuated as a function of increasing distance from the focus...

..The effects of training on sensory evoked responses are consistent with the proposal that perceptual learning is associated with changes in sensory cortices...

..The results demonstrated that early cortical encoding of the temporal structure of sound presented in silence is little or not affected by normal aging...

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..Neural markers of head orientation occur before those for gaze direction and the early structural encoding stages of face processing are view-dependant...

..This dynamic response modulation accounts for the N170 variations reported in the literature. The eyes may be central to what makes faces so special...

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..g., sound identity) is processed primarily along the ventral stream whereas sound location is processed along the dorsal stream and areas posterior to primary auditory cortex...

..Our results are consistent with a low-level stage of auditory scene analysis in which acoustic properties such as mistuning act as preattentive segregation cues that can subsequently lead to the perception of multiple auditory objects...

..Finally, scalp event-related potentials were not associated with the precedence effect until the gap occurred. This suggests that cortical mechanisms are engaged to maintain fusion when attributes in direct or reflected waves change...

..In addition, ERP components N2 and P3 were modulated by both intertrial contingency and task instructions, revealing the further influence of top-down mechanisms on concurrent sound segregation...

..The results indicate that even in the absence of musical training, the brain is set up to automatically encode music-specific melodic information, even when absolute pitch information is not available...

..Partial-least squares analyses revealed two significant latent variables that distinguished recollection and habit, consistent with the distinction between consciously controlled and automatic influences of memory...