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This study explores a method to investigate how people perceive temporal patterns through visuospatial representation. Experiment 1 utilized auditory and visual conditions to analyze responses to short tone sequences. Experiment 2 further validated the method with a 2AFC task involving tone sequence comparisons. Results indicate accuracy in mental representation. The findings offer evidence for rhythmic categorical perception and expand on previous research.
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Development of a visuospatial representation method and evidence for rhythmic categorical perception Amandine Penel, Christopher A. Hollweg, & Carlos D. Brody Cold Spring Harbor Laboratory Cold Spring Harbor, NY USA
Development of a visuospatial representation method to investigate the perception of temporal patterns • Serendipitous evidence for rhythmic categorical perception
Various processes have been proposed for the representation of temporal information in sequences, e.g.: • a multiple-look estimation of the mean time interval & variability (Drake & Botte, 1993) • the induction of a regular clock / entrainment of an attentional pulse (Povel & Essens, 1985; Large & Jones, 1999; Penel & Jones, 2005) • grouping by temporal proximity (Handel, 1998; Penel & Drake, 2004) • How do they interact? Are they the only ones to operate? (unlikely)
? Stimulus: Auditory, temporal 1 sec Mental representation • Top-down rationale employed by research: hypothesis about a process, temporal patterns selected accordingly. • A complementary bottom-up approach (Exp.1): the visuospatial representation method is exhaustive, the theory can then be driven by the data. Response: Visual, spatial • Fast, and if validated (Exp.1 control + Exp.2), gives a direct access to the mental representation.
Experiment 1 Method 1. Auditory experimental conditions (2. Visual control condition) 1 or 1.2 sec sequences (blocked) of 3 short tones (4 msec), with the middle tone randomly dividing the interval (uniform distribution, 1 msec sampling). 1200 trials in each tempo condition in 8 1-hour sessions.
1 2 NO GO NO NO 3 steps (1. Auditory experimental conditions) 2. Visual control condition Experiment 1 1000 trials in 2 1-hour sessions. 8 Ps (nonmusicians and amateur musicians), half began/finished with the control, tempo further counterbalanced.
Results Experiment 1 Raw data: For each participant: 1200 {stimulus, response} pairs in each auditory tempo condition, 1000 in the visual control condition. Looks like Gert’s plot, doesn’t it?
Experiment 1 P2 1-sec tempo Response (msec) Stimulus (msec)
Experiment 1 Average (N=8, 2 tempi + {N=4, 1 tempo Pilot}): Response (idem) Stimulus (% deviation from midpoint)
Experiment 1 Average visual control (N=8): Response (idem) Stimulus (% deviation from midpoint)
Experiment 1 Average auditory (N=12): Distributions of x-cross sections Response (idem) Stimulus (% deviation from midpoint)
Distributions of responses for stimuli: 0 -13.5 Bias Variability Experiment 1
0 -5 Probability Response (% deviation from midpoint) Experiment 1 The participants’ visuospatial report is an accurate reflection of their mental representation. SDT: distribution of responses == probability distribution, given the amplitude of a stimulation, that it originated from the stimulus in question. Genuine perceptual effects or artifacts of the method?
Experiment 1 Performance predictions in a 2AFC task (D = 4%):
1 sec D Experiment 2 Method Each trial consisted of 2 1-sec sequences of 3 tones with D = 4% (40 msec): Task: to indicate whether in the 2nd sequence compared to the 1st, the middle tone was played earlier (left button) or later (right button).
11 pairs chosen to highlight the triple-U pattern: Experiment 2 Presented in a random order, order of sequences in a pair counterbalanced. 150 repetitions per pair. 10 blocks of 11 pairs x 15 repetitions, in ~4 1-hour sessions. 13 participants (11 from Exp.1, 2 new).
Experiment 2 Results Predictions +/- SE (N = 12) Data +/- SE (N = 13)
Conclusion • Exhaustive • Bottom-up • Fast • Gives a direct access to the mental representation • We have developed a visuospatial representation method to investigate the perception of temporal patterns which is: • Evidence for rhythmic categorical perception (1:1 ratio), generalizing previous findings (Clarke, 1987; Schultze, 1989; Desain & Honing, 2003): • to a task which does not involve rhythmic categorization (or quantization) via (1) the use of musical notation and (2) the explicit instruction to disregard expressive timing, • to participants who are not highly musically trained. See also Gert and Ryota & Yoshitaka’s talks today! • Confirmed in a classic 2AFC experiment, validating the method
Conclusion Psychophysics of timing in 3-tones sequences: