Limits...
Predicting auditory space calibration from recent multisensory experience.

Mendonça C, Escher A, van de Par S, Colonius H - Exp Brain Res (2015)

Bottom Line: Multisensory experience can lead to auditory space recalibration.This study focuses on identifying the factors in recent sensory experience leading to such auditory space shifts.Sequences of five audiovisual pairs were presented, each randomly congruent or discrepant in space.

View Article: PubMed Central - PubMed

Affiliation: Department of Signal Processing and Acoustics, Aalto University, Otakaari 5, 02150, Espoo, Finland, Catarina.Hiipakka@aalto.fi.

ABSTRACT
Multisensory experience can lead to auditory space recalibration. After exposure to discrepant audiovisual stimulation, sound percepts are displaced in space, in the direction of the previous visual stimulation. This study focuses on identifying the factors in recent sensory experience leading to such auditory space shifts. Sequences of five audiovisual pairs were presented, each randomly congruent or discrepant in space. Each sequence was followed by a single auditory trial and two visual trials. In each trial, participants had to identify the perceived stimuli positions. We found that auditory localization is shifted during audiovisual discrepant trials and during subsequent auditory trials, suggesting a recalibration effect. Time did not lead to greater recalibration effects. The last audiovisual trial affects the subsequent auditory shift the most. The number of discrepant trials in a sequence, and the number of consecutive trials in sequence, also correlated with the subsequent auditory shift. To estimate the individual contribution of previously presented trials to the recalibration effect, a best-fitting model was developed to predict the shift in a linear weighted combination of stimulus features: (1) whether matching or discrepant trials occurred in the sequence, (2) total number of discrepant trials, and (3) maximum number of consecutive discrepant trials, (4) whether the last trial was discrepant or not. The selected model consists of a function including as properties the type of stimulus of the last audiovisual sequence trial and the overall probability of mismatching trials in sequence.

No MeSH data available.


Related in: MedlinePlus

Cumulative responses in unimodal trials. The scale has been collapsed so that 0° corresponds to stimulus position. In the auditory subplot, the position of the visual stimulus in the previous audiovisual discrepant trials was at +12° (gray line). In the visual subplot, the position of the auditory stimulus in the previous audiovisual discrepant trials was at −12° (gray line). Data points correspond to the cumulative proportion of responses at each spatial position relative to the source. For example, the values at 5° reveal the proportion of times the stimuli were localized anywhere in the left and up to 5° to the right of the stimulus. Data points are per subject (S1–S11), and each represents 288 trials in the auditory subplot and 576 trials in the visual subplot. The scale has been obtained by subtracting the stimulus position to the stimulus response, correcting across subjects with different orientation of discrepant trials, and computing the cumulative relative frequencies. The psychometric curves were obtained using the logistic function. Auditory estimates were shifted and varied across participants. Visual estimates were accurate and stable across participants (color figure online)
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4464732&req=5

Fig2: Cumulative responses in unimodal trials. The scale has been collapsed so that 0° corresponds to stimulus position. In the auditory subplot, the position of the visual stimulus in the previous audiovisual discrepant trials was at +12° (gray line). In the visual subplot, the position of the auditory stimulus in the previous audiovisual discrepant trials was at −12° (gray line). Data points correspond to the cumulative proportion of responses at each spatial position relative to the source. For example, the values at 5° reveal the proportion of times the stimuli were localized anywhere in the left and up to 5° to the right of the stimulus. Data points are per subject (S1–S11), and each represents 288 trials in the auditory subplot and 576 trials in the visual subplot. The scale has been obtained by subtracting the stimulus position to the stimulus response, correcting across subjects with different orientation of discrepant trials, and computing the cumulative relative frequencies. The psychometric curves were obtained using the logistic function. Auditory estimates were shifted and varied across participants. Visual estimates were accurate and stable across participants (color figure online)

Mentions: In this section, data are analyzed without regarding the prior stimulus type that was presented. There were no differences between localization of visual and auditory stimuli presented in the central, left, or right area, in the bimodal and unimodal trials. Therefore, all data are presented together.In Fig. 2, localization results are shown for auditory and visual trials. In that figure, responses were normalized for each subject by subtracting all pooled stimulus responses to the corresponding stimulus positions. Note that half of the subjects always had the auditory stimulus to the left of the visual stimulus and the other half were presented in the reverse way. In the later case, data were inversed such that results can be collapsed across the two groups.Fig. 2


Predicting auditory space calibration from recent multisensory experience.

Mendonça C, Escher A, van de Par S, Colonius H - Exp Brain Res (2015)

Cumulative responses in unimodal trials. The scale has been collapsed so that 0° corresponds to stimulus position. In the auditory subplot, the position of the visual stimulus in the previous audiovisual discrepant trials was at +12° (gray line). In the visual subplot, the position of the auditory stimulus in the previous audiovisual discrepant trials was at −12° (gray line). Data points correspond to the cumulative proportion of responses at each spatial position relative to the source. For example, the values at 5° reveal the proportion of times the stimuli were localized anywhere in the left and up to 5° to the right of the stimulus. Data points are per subject (S1–S11), and each represents 288 trials in the auditory subplot and 576 trials in the visual subplot. The scale has been obtained by subtracting the stimulus position to the stimulus response, correcting across subjects with different orientation of discrepant trials, and computing the cumulative relative frequencies. The psychometric curves were obtained using the logistic function. Auditory estimates were shifted and varied across participants. Visual estimates were accurate and stable across participants (color figure online)
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4464732&req=5

Fig2: Cumulative responses in unimodal trials. The scale has been collapsed so that 0° corresponds to stimulus position. In the auditory subplot, the position of the visual stimulus in the previous audiovisual discrepant trials was at +12° (gray line). In the visual subplot, the position of the auditory stimulus in the previous audiovisual discrepant trials was at −12° (gray line). Data points correspond to the cumulative proportion of responses at each spatial position relative to the source. For example, the values at 5° reveal the proportion of times the stimuli were localized anywhere in the left and up to 5° to the right of the stimulus. Data points are per subject (S1–S11), and each represents 288 trials in the auditory subplot and 576 trials in the visual subplot. The scale has been obtained by subtracting the stimulus position to the stimulus response, correcting across subjects with different orientation of discrepant trials, and computing the cumulative relative frequencies. The psychometric curves were obtained using the logistic function. Auditory estimates were shifted and varied across participants. Visual estimates were accurate and stable across participants (color figure online)
Mentions: In this section, data are analyzed without regarding the prior stimulus type that was presented. There were no differences between localization of visual and auditory stimuli presented in the central, left, or right area, in the bimodal and unimodal trials. Therefore, all data are presented together.In Fig. 2, localization results are shown for auditory and visual trials. In that figure, responses were normalized for each subject by subtracting all pooled stimulus responses to the corresponding stimulus positions. Note that half of the subjects always had the auditory stimulus to the left of the visual stimulus and the other half were presented in the reverse way. In the later case, data were inversed such that results can be collapsed across the two groups.Fig. 2

Bottom Line: Multisensory experience can lead to auditory space recalibration.This study focuses on identifying the factors in recent sensory experience leading to such auditory space shifts.Sequences of five audiovisual pairs were presented, each randomly congruent or discrepant in space.

View Article: PubMed Central - PubMed

Affiliation: Department of Signal Processing and Acoustics, Aalto University, Otakaari 5, 02150, Espoo, Finland, Catarina.Hiipakka@aalto.fi.

ABSTRACT
Multisensory experience can lead to auditory space recalibration. After exposure to discrepant audiovisual stimulation, sound percepts are displaced in space, in the direction of the previous visual stimulation. This study focuses on identifying the factors in recent sensory experience leading to such auditory space shifts. Sequences of five audiovisual pairs were presented, each randomly congruent or discrepant in space. Each sequence was followed by a single auditory trial and two visual trials. In each trial, participants had to identify the perceived stimuli positions. We found that auditory localization is shifted during audiovisual discrepant trials and during subsequent auditory trials, suggesting a recalibration effect. Time did not lead to greater recalibration effects. The last audiovisual trial affects the subsequent auditory shift the most. The number of discrepant trials in a sequence, and the number of consecutive trials in sequence, also correlated with the subsequent auditory shift. To estimate the individual contribution of previously presented trials to the recalibration effect, a best-fitting model was developed to predict the shift in a linear weighted combination of stimulus features: (1) whether matching or discrepant trials occurred in the sequence, (2) total number of discrepant trials, and (3) maximum number of consecutive discrepant trials, (4) whether the last trial was discrepant or not. The selected model consists of a function including as properties the type of stimulus of the last audiovisual sequence trial and the overall probability of mismatching trials in sequence.

No MeSH data available.


Related in: MedlinePlus