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Temporal order judgement for auditory and visual stimuli

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Kanabus M., Szelag E., Rojek E., Poppel E.

Acta Neurobiologiae Experimentalis

2002

vol. 62

issue 4

263-270

The ability to perceive temporal order for pairs of auditory and visual stimuli was investigated in 12 volunteers. They were asked to make judgements about the order of presented stimuli by pressing two response buttons in a certain order. The performance on auditory and visual tests was studied in relation to the Inter-Stimulus-Interval (ISI), which varied from 5 to 500 ms. In general, the level of performance was similar for the two modalities and the criterion of 75% of correct responses was reached at ISI longer than 40 ms, independently of the modality. These findings are consistent with previous research. However, at ISI of 5 ms, a significantly higher level of correctness was observed for the auditory than visual task. Such a tendency was also observed for ISIs of 10, 20 and 40 ms. Better processing in the auditory compared to the visual task at shorter ISIs may result from a different kind of transduction mechanism at the level of receptive cells in each modality. Alternatively, subjects may use two different kinds of response strategies in the auditory modality, only one being comparable to the response strategy in the visual modality.

The P3 produced by auditory stimuli presented in a passive and active condition: modulation by visual stimuli

100%

Wronka E., Kuniecki M., Kaiser J., Coenen A. M.

Acta Neurobiologiae Experimentalis

2007

vol. 67

issue 2

155-164

The aim of this study was to investigate how the processing of auditory stimuli is affected by the simultaneous presentation of visual stimuli. This was approached in an active and passive condition, during which a P3 was elicited in the human EEG by single auditory stimuli. Subjects were presented tones, either alone or accompanied by the simultaneous exposition of pictures. There were two different sessions. In the first, the presented tones demanded no further cognitive activity from the subjects (passive or 'ignore' session), while in the second session subjects were instructed to count the tones (active or 'count' session). The central question was whether inter-modal influences of visual stimulation in the active condition would modulate the auditory P3 in the same way as in the passive condition. Brain responses in the ignore session revealed only a small P3-like component over the parietal and frontal cortex, however, when the auditory stimuli co-occurred with the visual stimuli, an increased frontal activity in the window of 300-500 ms was observed. This could be interpreted as the reflection of a more intensive involuntary attention shift, provoked by the preceding visual stimulation. Moreover, it was found that cognitive load caused by the count instruction, resulted in an evident P3, with maximal amplitude over parietal locations. This effect was smaller when auditory stimuli were presented on the visual background. These findings might support the thesis that available resources were assigned to the analysis of visual stimulus, and thus were not available to analyze the subsequent auditory stimuli. This reduction in allocation of resources for attention was restricted to the active condition only, when the matching of a template with incoming information results in a distinct P3 component. It is discussed whether the putative source of this effect is a change in the activity of the frontal cortex.

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2 Acta Neurobiologiae Experimentalis

1 2007

1 2002

1 Coenen A. M.

1 Kaiser J.

1 Kanabus M.

1 Kuniecki M.

1 Poppel E.

1 Rojek E.

1 Szelag E.

1 Wronka E.

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Temporal order judgement for auditory and visual stimuli

The P3 produced by auditory stimuli presented in a passive and active condition: modulation by visual stimuli