An investigation of the auditory streaming effect using event‐related brain potentials

Abstract

There is uncertainty concerning the extent to which the auditory streaming effect is a function of attentive or preattentive mechanisms. The mismatch negativity~MMN!, which indexes preattentive acoustic processing, was used to probe whether the segregation associated with the streaming effect occurs preattentively. In Experiment 1, alternating high and low tones were presented at fast and slow paces while subjects ignored the stimuli. At the slow pace, tones were heard as alternating high and low pitches, and no MMN was elicited. At the fast pace a streaming effect was induced and an MMN was observed for the low stream, indicating a preattentive locus for the streaming effect. The high deviant did not elicit an MMN. MMNs were obtained to both the high and low deviants when the interval between the across-stream deviance was lengthened to more than 250 ms in Experiment 2, indicating that the MMN system is susceptible to processing constraints.Descriptors: Auditory stream segregation, Mismatch negativity, Event-related potentials, Streaming effect, Auditory sensory memory Multiple sources of acoustic energy can impinge on the ear constantly in our everyday experience. It is not uncommon for the sounds of voices and office equipment or the ringing of telephones to occur simultaneously. The task of the brain is to tease apart the cacophony of these sounds, forming meaningful representations of the incoming acoustic information. This process requires a mechanism for segregating the inputs into their original sources. A now classic example, the cocktail party phenomenon, illustrates the ease with which the brain is able to perform this task. Amid the steady din of party sounds~e.g., tinkling of glasses, multiple conversations, music!, the brain keeps the sources distinct. Auditory cues such as the location of the sound or the pitch of a speaker's voice help this process of segregating the total stream of sound, which has been called auditory stream segregation~Bregman, 1990!.When tones of a sufficient frequency separation are alternated continuously at a fast enough rate for a period of time, a streaming effect occurs~Bregman, 1978, 1990Bregman & Campbell, 1971!. The streaming effect, an aspect of stream segregation, is a perceptual phenomenon governed by both the rate of stimulation and the frequency relationship of a tonal sequence. The perception is that the sets of high and low tones split into separate streams of sound, one formed of the high tones and one formed of the low tones. It sounds somewhat like counterpoint in music, as though the two streams are occurring independently and simultaneously. The purpose of this perceptual segregation is presumably to sort the tones in terms of sound sources, thereby improving the ability to perceive patterns within them. Natural differences of acoustic properties emanating from different sound sources are often reflected in pitch~e.g., the voice of a man vs. the voice of a woman!. Therefore, within a mixture of sounds striking the ear, it is likely that sounds in a high fr...

Newborn infants can organize the auditory world

“…With a constant frequency separation between high and low tones, the presentation rate controls whether the high and low tones are perceived as two separate sound streams (fast presentation rates) or as a single stream that includes all tones (slow presentation rates) (2). In full accordance with this defining characteristic of auditory streaming, it has been shown that, when sequences of high and low tones with separate regular characteristics were mixed together, increasing the rate of stimulus presentation (while frequency separation remained constant) resulted in the elicitation of deviancerelated brain responses by occasional violations of one or the other acoustic regularity (9). Therefore, we conclude that the current results demonstrated the operation of auditory-stream segregation mechanisms in newborn infants.…”

Human Cortical Activity during Streaming without Spectral Cues Suggests a General Neural Substrate for Auditory Stream Segregation

“…The neural underpinnings of auditory stream segregation have been investigated with intracortical recordings in animals (Fishman et al, 2001(Fishman et al, , 2004Kanwal et al, 2003;Klump, 2004, 2005;Micheyl et al, 2005), and noninvasively in humans, using electroencephalography (EEG) (Sussman et al, 1999, Sussman, 2005Snyder et al, 2006), magnetoencephalography (MEG) (Gutschalk et al, 2005), and functional magnetic resonance imaging (fMRI) (Deike et al, 2004;Cusack, 2005;Wilson et al, 2007). All of these studies have used pairs of sounds that differed in frequency content, and were presented alternately, or in other repeating temporal patterns.…”

Neurophysiological evidence for context-dependent encoding of sensory input in human auditory cortex

“…The mismatch negativity (MMN) component of event-related brain potentials (ERPs) reflects the outcome of a change detection process that is based upon the memory of sound regularities (often called the "standard") in ongoing auditory input Näätänen and Winkler, 1999;Picton et al, 2000;Sussman and Gumenyuk, 2005;Sussman et al, 1998bSussman et al, , 1999Sussman et al, , 2002aWinkler et al, 1996). Incoming sounds that deviate from the neural representation of the standard sound elicit MMN.…”

“…Incoming sounds that deviate from the neural representation of the standard sound elicit MMN. Infrequent changes in simple auditory features such as frequency, intensity, tone duration, or spatial location, as well as changes in more complex features such as sequential tone patterns, elicit MMN (e.g., Sussman et al, 1999, for review, see Näätänen et al, 2001). MMN is typically observed with a peak latency between 100 and 200 ms from the time that the deviation from the regularity is detected.…”