We are developing special-purpose, low-power analog-to-digital converters for speech and music applications, that feature analog circuit models of biological audition to process the audio signal before conversion. This paper describes our most recent converter design, and a working system that uses several copies of the chip to compute multiple representations of sound from an analog input. Thi...

The sound of a busy environment, such as a city street, gives rise to a perception of numerous distinct events in a human listener – the ‘auditory scene analysis’ of the acoustic information. Recent advances in the understanding of this process from experimental psychoacoustics have led to several efforts to build a computer model capable of the same function. This work is known as ‘computation...

This paper presents a methodology for the design of fast-rate auditory presentations based on the Auditory Scene Analysis of Bregman. The auditory scene is hierarchically organized and based on the concept of auditory streams described in terms of two types of structures, one across streams (at an instant) and one within each stream (over time). Each stream constitutes a perceptual entity on wh...

Various grouping attributes have been translated into successful signal processing techniques that may be used in source separation, e.g., to separate speech from background. However, separation is not enough to know: What is the source of the sound? A next step beyond primitive ASA is schema-based ASA, to give meaning to the source, i.e. to map bottom-up audio features to the meaningful conten...

Speech understanding in complex and dynamic listening environments requires (a) auditory scene analysis, namely auditory object formation and segregation, and (b) allocation of the attentional focus to the talker of interest. There is evidence that pre-information is actively used to facilitate these two aspects of the so-called "cocktail-party" problem. Here, a simulated multi-talker scenario ...

What is the involvement of what we know in what we perceive? In this article, the contribution of melodic schema-based processes to the perceptual organization of tone sequences is examined. Two unfamiliar six-tone melodies, one of which was interleaved with distractor tones, were presented successively to listeners who were required to decide whether the melodies were identical or different. I...

We have recently proposed neural timing networks that operate on temporal fine structure of inputs to build up and separate periodic signals with different fundamental periods (Neural Networks, 14: 737-753, 2001). Simple recurrent nets consist of arrays of coincidence detectors fed by common input lines and conduction delay loops of different recurrence times. Short-term facilitation amplifies ...

Segmenting the complex acoustic mixture that makes a typical auditory scene into relevant perceptual objects is one of the main challenges of the auditory system [1], for both human and nonhuman species. Several recent studies indicate that perceptual auditory object formation, or "streaming," may be based on neural activity within the auditory cortex and beyond [2, 3]. Here, we find that scene...

Auditory scene analysis is a demanding computational process that is performed automatically and efficiently by the healthy brain but vulnerable to the neurodegenerative pathology of Alzheimer's disease. Here we assessed the functional neuroanatomy of auditory scene analysis in Alzheimer's disease using the well-known 'cocktail party effect' as a model paradigm whereby stored templates for audi...