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Titia L van Zuijen

Publications and source records attributed to Titia L van Zuijen.

5 recordsLinked to original sources

Object representation in the human auditory system.

One important principle of object processing is exclusive allocation. Any part of the sensory input, including the border between two objects, can only belong to one object at a time. We tested whether tones forming a spectro-temporal border between two sound patterns can belong to both patterns at the same time. Sequences were composed of low-, intermediate- and high-pitched tones. Tones were delivered with short onset-to-onset intervals causing the high and low tones to automatically form separate low and high sound streams. The intermediate-pitch tones could be perceived as part of either one or the other stream, but not both streams at the same time. Thus these tones formed a pitch 'border' between the two streams. The tones were presented in a fixed, cyclically repeating order. Linking the intermediate-pitch tones with the high or the low tones resulted in the perception of two different repeating tonal patterns. Participants were instructed to maintain perception of one of the two tone patterns throughout the stimulus sequences. Occasional changes violated either the selected or the alternative tone pattern, but not both at the same time. We found that only violations of the selected pattern elicited the mismatch negativity event-related potential, indicating that only this pattern was represented in the auditory system. This result suggests that individual sounds are processed as part of only one auditory pattern at a time. Thus tones forming a spectro-temporal border are exclusively assigned to one sound object at any given time, as are spatio-temporal borders in vision.

Acoustic Stimulation↗

Implicit, intuitive, and explicit knowledge of abstract regularities in a sound sequence: an event-related brain potential study.

Implicit knowledge has been proposed to be the substrate of intuition because intuitive judgments resemble implicit processes. We investigated whether the automatically elicited mismatch negativity (MMN) component of the auditory event-related potentials (ERPs) can reflect implicit knowledge and whether this knowledge can be utilized for intuitive sound discrimination. We also determined the sensitivity of the attention-and task-dependent P3 component to intuitive versus explicit knowledge. We recorded the ERPs elicited in an "abstract" oddball paradigm. Tone pairs roving over different frequencies but with a constant ascending inter-pair interval, were presented as frequent standard events. The standards were occasionally replaced by deviating, descending tone pairs. The ERPs were recorded under both ignore and attend conditions. Subjects were interviewed and classified on the basis of whether or not they could datect the deviants. The deviants elicited an MMN even in subjects who subsequent to the MMN recording did not express awareness of the deviants. This suggests that these subjects possessed implicit knowledge of the sound-sequence structure. Some of these subjects learned, in an associative training session, to detect the deviants intuitively, that is, they could detect the deviants but did not give a correct description of how the deviants differed from the standards. Intuitive deviant detection was not accompanied by P3 elicitation whereas subjects who developed explicit knowledge of the sound sequence during the training did show a P3 to the detected deviants.

Acoustic Stimulation↗

To musicians, the message is in the meter pre-attentive neuronal responses to incongruent rhythm are left-lateralized in musicians.

Musicians exchange non-verbal cues as messages when they play together. This is particularly true in music with a sketchy outline. Jazz musicians receive and interpret the cues when performance parts from a regular pattern of rhythm, suggesting that they enjoy a highly developed sensitivity to subtle deviations of rhythm. We demonstrate that pre-attentive brain responses recorded with magnetoencephalography to rhythmic incongruence are left-lateralized in expert jazz musicians and right-lateralized in musically inept non-musicians. The left-lateralization of the pre-attentive responses suggests functional adaptation of the brain to a task of communication, which is much like that of language.

Acoustic Stimulation↗

Auditory organization of sound sequences by a temporal or numerical regularity--a mismatch negativity study comparing musicians and non-musicians.

The human auditory system can encode regularities in the acoustic environment without the requirement of attention. We investigated whether the auditory system of musicians is more sensitive than that of non-musicians in encoding complex regularities. We presented tone sequences containing either a temporal or a numerical regularity. The sequence with the temporal regularity could be divided into segments of a constant duration while the segments contained a varying number of tones. The sequence with the numerical regularity, on the other hand, could be divided into segments containing a constant number of tones while the segments varied in duration. Auditory encoding of the regularity was determined by measuring whether an occasional segment lengthening, either in time or by number elicited the mismatch negativity (MMN). In both musicians and non-musicians, an MMN was elicited when the temporal regularity was violated. In contrast, only in musicians an MMN was elicited to violations of the numerical regularity. The results show that temporal processing is of general importance in audition since at an involuntary auditory processing stage a complex temporal regularity can be encoded irrespective of musical expertise. Furthermore, the auditory system of professional musicians can encode a numerical regularity without attention being required reflecting the functional importance of beat tracking in the perceptual organization of music.

Adult↗

Grouping of sequential sounds--an event-related potential study comparing musicians and nonmusicians.

It is believed that auditory processes governing grouping and segmentation of sounds are automatic and represent universal aspects of music perception (e.g., they are independent of the listener's musical skill). The present study challenges this view by showing that musicians and nonmusicians differ in their ability to preattentively group consecutive sounds. We measured event-related potentials (ERPs) from professional musicians and nonmusicians who were presented with isochronous tone sequences that they ignored. Four consecutive tones in a sequence could be grouped according to either pitch similarity or good continuation of pitch. Occasionally, the tone-group length was violated by a deviant tone. The mismatch negativity (MMN) was elicited to the deviants in both subject groups when the sounds could be grouped based on pitch similarity. In contrast, MMN was only elicited in musicians when the sounds could be grouped according to good continuation of pitch. These results suggest that some forms of auditory grouping depend on musical skill and that not all aspects of auditory grouping are universal.

Acoustic Stimulation↗