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Timing Rhythms: Perceived Duration Increases with a Predictable Temporal Structure of Short Interval Fillers.

Horr NK, Di Luca M - PLoS ONE (2015)

Bottom Line: One account to explain effects of temporal structure is a non-linear accumulator-counter mechanism reset at the beginning of every subinterval.No general over- or underestimation is registered for rhythmically grouped compared to isochronous intervals.Implications of these findings for a non-linear clock model as well as a neural response magnitude account of perceived duration are discussed.

View Article: PubMed Central - PubMed

Affiliation: Centre for Computational Neuroscience and Cognitive Robotics, Department of Psychology, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom.

ABSTRACT
Variations in the temporal structure of an interval can lead to remarkable differences in perceived duration. For example, it has previously been shown that isochronous intervals, that is, intervals filled with temporally regular stimuli, are perceived to last longer than intervals left empty or filled with randomly timed stimuli. Characterizing the extent of such distortions is crucial to understanding how duration perception works. One account to explain effects of temporal structure is a non-linear accumulator-counter mechanism reset at the beginning of every subinterval. An alternative explanation based on entrainment to regular stimulation posits that the neural response to each filler stimulus in an isochronous sequence is amplified and a higher neural response may lead to an overestimation of duration. If entrainment is the key that generates response amplification and the distortions in perceived duration, then any form of predictability in the temporal structure of interval fillers should lead to the perception of an interval that lasts longer than a randomly filled one. The present experiments confirm that intervals filled with fully predictable rhythmically grouped stimuli lead to longer perceived duration than anisochronous intervals. No general over- or underestimation is registered for rhythmically grouped compared to isochronous intervals. However, we find that the number of stimuli in each group composing the rhythm also influences perceived duration. Implications of these findings for a non-linear clock model as well as a neural response magnitude account of perceived duration are discussed.

No MeSH data available.


Related in: MedlinePlus

Results of Experiment 1.(A) Proportions of responses indicating the rhythmic interval to be longer than the random interval as a function of physical duration difference. (B) Point of subjective equality (PSE) and just noticeable difference (JND) calculated from response proportions with the Spearman-Kärber method. Error bars are S.E.M.
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pone.0141018.g002: Results of Experiment 1.(A) Proportions of responses indicating the rhythmic interval to be longer than the random interval as a function of physical duration difference. (B) Point of subjective equality (PSE) and just noticeable difference (JND) calculated from response proportions with the Spearman-Kärber method. Error bars are S.E.M.

Mentions: Response Proportions, PSE and JND values separated by rhythm condition are shown in Fig 2. As there is no significant difference between the PSE and JND for the three group-of-2 rhythms with different number of groups (one-way r.m. ANOVA on PSE: F(2,46) = 0.37, p = 0.69, ηp² = 0.02; on JND F(2,46) = 0.57, p = 0.56, ηp² = 0.02), the results for the group-of-2 rhythms are presented together. The PSE averaged across the four rhythmic conditions is significantly lower than zero (-60±18ms, t-test against 0, two-tailed: t(23) = -3.1, p = 0.006, d = 0.62), indicating that rhythmic intervals are perceived as longer than anisochronous intervals. The duration required for an anisochronous stimulus to match a rhythmic one does not differ for rhythms composed of groups of different number (one-way r.m. ANOVA on PSE, F(3,69) = 0.24, p = 0.87, ηp² = 0.01). The overall JND indicates that people were able to discriminate within the given range of 500ms duration difference (378±18ms). JND does not significantly vary across conditions (one-way r.m. ANOVA on JND, F(3,69) = 1.93, p = 0.13, ηp² = 0.08). Overall, the data highlights a general underestimation of the duration of random intervals compared to rhythmic intervals.


Timing Rhythms: Perceived Duration Increases with a Predictable Temporal Structure of Short Interval Fillers.

Horr NK, Di Luca M - PLoS ONE (2015)

Results of Experiment 1.(A) Proportions of responses indicating the rhythmic interval to be longer than the random interval as a function of physical duration difference. (B) Point of subjective equality (PSE) and just noticeable difference (JND) calculated from response proportions with the Spearman-Kärber method. Error bars are S.E.M.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4608791&req=5

pone.0141018.g002: Results of Experiment 1.(A) Proportions of responses indicating the rhythmic interval to be longer than the random interval as a function of physical duration difference. (B) Point of subjective equality (PSE) and just noticeable difference (JND) calculated from response proportions with the Spearman-Kärber method. Error bars are S.E.M.
Mentions: Response Proportions, PSE and JND values separated by rhythm condition are shown in Fig 2. As there is no significant difference between the PSE and JND for the three group-of-2 rhythms with different number of groups (one-way r.m. ANOVA on PSE: F(2,46) = 0.37, p = 0.69, ηp² = 0.02; on JND F(2,46) = 0.57, p = 0.56, ηp² = 0.02), the results for the group-of-2 rhythms are presented together. The PSE averaged across the four rhythmic conditions is significantly lower than zero (-60±18ms, t-test against 0, two-tailed: t(23) = -3.1, p = 0.006, d = 0.62), indicating that rhythmic intervals are perceived as longer than anisochronous intervals. The duration required for an anisochronous stimulus to match a rhythmic one does not differ for rhythms composed of groups of different number (one-way r.m. ANOVA on PSE, F(3,69) = 0.24, p = 0.87, ηp² = 0.01). The overall JND indicates that people were able to discriminate within the given range of 500ms duration difference (378±18ms). JND does not significantly vary across conditions (one-way r.m. ANOVA on JND, F(3,69) = 1.93, p = 0.13, ηp² = 0.08). Overall, the data highlights a general underestimation of the duration of random intervals compared to rhythmic intervals.

Bottom Line: One account to explain effects of temporal structure is a non-linear accumulator-counter mechanism reset at the beginning of every subinterval.No general over- or underestimation is registered for rhythmically grouped compared to isochronous intervals.Implications of these findings for a non-linear clock model as well as a neural response magnitude account of perceived duration are discussed.

View Article: PubMed Central - PubMed

Affiliation: Centre for Computational Neuroscience and Cognitive Robotics, Department of Psychology, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom.

ABSTRACT
Variations in the temporal structure of an interval can lead to remarkable differences in perceived duration. For example, it has previously been shown that isochronous intervals, that is, intervals filled with temporally regular stimuli, are perceived to last longer than intervals left empty or filled with randomly timed stimuli. Characterizing the extent of such distortions is crucial to understanding how duration perception works. One account to explain effects of temporal structure is a non-linear accumulator-counter mechanism reset at the beginning of every subinterval. An alternative explanation based on entrainment to regular stimulation posits that the neural response to each filler stimulus in an isochronous sequence is amplified and a higher neural response may lead to an overestimation of duration. If entrainment is the key that generates response amplification and the distortions in perceived duration, then any form of predictability in the temporal structure of interval fillers should lead to the perception of an interval that lasts longer than a randomly filled one. The present experiments confirm that intervals filled with fully predictable rhythmically grouped stimuli lead to longer perceived duration than anisochronous intervals. No general over- or underestimation is registered for rhythmically grouped compared to isochronous intervals. However, we find that the number of stimuli in each group composing the rhythm also influences perceived duration. Implications of these findings for a non-linear clock model as well as a neural response magnitude account of perceived duration are discussed.

No MeSH data available.


Related in: MedlinePlus