An Exploration of Timing Abilities from Nineteen to Ninety

1. Rhythm Perception & Production Workshop 2005, July, 3rd An Exploration of Timing Abilities from Nineteen to Ninety Martine Turgeon Lawrence W. Taylor Alan M. Wing Contact: M.Turgeon@Bham.ac.uk SyMoN

2. Researching ‘Timing & Aging’ : 1. Main Question and Objectives • Q. : How does the detection and correction of a Phase Shift (PS) perturbation in synchronization to otherwise isochronous sequences with Inter-Onset Intervals (IOI) spanning the pulsation range vary withage in non-musical experts? • No work has been done on that specific issue. • Yes, but why is it an interesting issue? …that should become clear by the end of the talk! If not, keep the question in mind and ask it!! • However, interesting work has been done on ‘the internal clock’ slowing with aging as well as on rhythmic tapping with musical experts and non experts of different ages. • Let’s review that work on ‘Timing and Aging’

3. Researching ‘Timing & Aging’ : 2. Is ‘the clock’ ticking more slowly over time? Assuming that: Spontaneous motor tempo reflects internal time mechanism. Baudouin, A., Vanneste, S., and Isingrini, M. (2002) found supporting evidence that internal timing mechanisms slow with age. Drake, Jones and Baruch (2000) also found supporting evidence for that at the lower end of the age spectrum (young children to young adults).

4. Researching ‘Timing & Aging’ : 2. Is ‘the clock’ ticking more slowly over time? (ctnd.) • Assuming that: A greater variability in inter-tap intervals reflects an underlying ‘slower internal clock’ . • Age-comparative studies of timed finger tapping provide conflicting evidence as to whether or not the ‘clock’ slows with age: • Woodruff-Pak & Jaeger (1998) found age-related increases in internal clock variability; • Greene and Williams (1993) found NO age-related increases in internal clock variability; • Duchek, Balota, & Ferraro (1994) found age-related increases in internal clock variability only in participants who showed early dementia. NOTE: Task done with single isochronous interval (550 ms)

5. Researching ‘Timing & Aging’ : 3. Rhythmic processes, models & Krampe’s work • The results of Krampe et al., (2002) support some age-related deficits in complex bimanual tapping which can be overcome by musical expertise, but noton tapping to a simple isochronous sequence. • Krampe concludes that: • both the motor implementation and timekeeper executionprocesses show • similar levels of functioning in young and older adults. • On the other hand, target specification processes are clearly affected by age. • For more detailed on these rhythmic processes and associated models, I refer you to Krampe’s work and to the rhythm program hypothesis proposed by Vorberg and Wing (1996).

6. The heart of the matter: 1. Specific Questions and Objectives • What are the perceptual limits for detecting a phase-shift perturbation in an isochronous sequence? • Is it affected by tempi? If so, how? • Is it affected by tapping (synchronization)? If so how? • Do so in “non musician” neurologically-intact adults from early 20’s to late 80’s. • Do so within dual- and single- task contexts • Do so with a fast procedure

7. The heart of the matter: 1. Specific Questions and Objectives (ctnd.) These would address the following objectives: 1. generalize Repp’s conclusion on sensorimotor synchronization beyond a 2-Hz context and to a ‘normal’ or non-musician population; 2. establish ‘age-related norms’ against which timing deficits can be assessed in schizophrenics as well as in stroke patients. 3. tease apart sensory from sensorimotor factors in the detection and synchronization performance.

8. The heart of the matter: 1. What about hypotheses? It all depends on another question:“Does error detection and correction in audio-guided action, like the synchronization tapping task used in this study truly ‘bypass’ any rhythm program (target specification processes), being completely dependent on ‘low level’ pre-attentive motor implementationand timekeeper execution processesin Krampe’s terms, or is it rather partly dependent (in some conditions) on them? In other words, is timing error detection and correction across the temporal frequency range evoking a spontaneous ‘pulse sensation’ (audiomotor ‘entrainment’ zone) ‘simple’ or ‘complex’ (to borrow again from Krampe’s rhythmic tasks’ classification scheme) in the general population?

9. The heart of the matter: 2. Methodology and Design • Participants • 50 neurologically-intact adults • 10 non-rhythm experts in each of 4 age groups: • 19-35 (Mean Age: 27.4) • 36-55 (Mean Age: 46.4) • 56-75 (Mean Age: 67.1) • 76+ (Mean Age: 84.8) • 10 rhythm experts (presented only if time allows) with: • 5 years of formal musical or ‘rhythmic dance’ (e.g. flamenco) training and/or • 10 years of regular practice of a musical instruments or ‘rhythmic dance’

10. Psychophysical correlates of PS detection & correctionin isochronous sequences of 3 tempi: 300-ms IOI 600-ms IOI 900-ms IOI The heart of the matter: 2. Methodology and Design (ctnd) For 3 conditions: • Single-task context 1. Detection:Evaluation of temporal JND using a 1 Up/2 Dn adaptive staircase procedure (Levitt, 1971); 2. Synchronization:Error correction is evaluated through the Tap-Tone Asynchronies (TTA) from T-3 to T+5. TTA’s in turn are used to compute Compensation Functions (CF’s) for PS below, at or above JND’s. • Dual-task context 3. Detection + Synchronization

11. IOI = 300 ms The heart of the matter: 2. Tasks and Demos Trial structure +8 1 2 3 4 5 6 7 8 9 10 11

12. IOI = 600 ms The heart of the matter: 2. Tasks and Demos (ctnd.) Trial structure +8 1 2 3 4 5 6 7 8 9 10 11

13. IOI = 900 ms The heart of the matter: 2. Tasks and Demos (ctnd.) Trial structure +8 1 2 3 4 5 6 7 8 9 10 11

14. T -3 -2 T-1 -6 -5 -4 T+1 +2 +3 +4 • IOI = 300 ms PS = 75 ms The heart of the matter: 2. Tasks and Demos (ctnd.) Phase-Shift Detection task using adaptive staircase procedure: start at PS=IOI/4 e.g. staircase at fast rate “Is there an TEMPORAL IRREGULARITY in the sequence?” Yes

15. T -3 -2 T-1 T+1 +2 +3 +4 -6 -5 -4 • IOI = 300 ms PS = 7 ms !!! The heart of the matter: 2. Tasks and Demos (ctnd.) Phase-Shift Detection at 3.33 Hz: …later in the staircase procedure No! “Is there an TEMPORAL IRREGULARITY in the sequence?”

16. Results: 1. Perceptual • Mean Just-Detectable Phase-Shifts (JND)’s • for 11 Rhythm Experts and Age-Matched Non Experts: • for youngest vs. eldest age group of 10 non experts each

17. Results: 2. Perceptual Motor Mean Compensations Functions (CF’s) with Relative Tap-Tone Asynchronies (TTA’s) for the fast rate for 4 Age Groups of 10 Non Experts each NOTE: all at 300-ms IOI except for the elderly at 600-ms IOI

18. Results: 2. Perceptual Motor (ctnd.) • Mean CF’s with Relative TTA’s: • for the medium rate for 4 Age Groups of 10 Non Experts each NOTE: all at 600-ms IOI except for the elderly at 750-ms IOI

19. Results: 2. Perceptual Motor (ctnd.) • Mean CF’s with Relative TTA’s: • for the slow rate for 4 Age Groups of 10 Non Experts each NOTE: all at 900-ms IOI this time!

20. Results: 3. Preferred Rate, Fastest Rate and Time-Interval Estimation through Mean IRI Production in the Young vs. Elderly groups

21. Summary of Results, Conclusions & Further Questions: 1. Perceptual (PS Detection) Summary PS-detection thresholds: • were lower for our ‘rhythm experts’ (8-10 % of IOI) than age-matched non experts (10-12 % of IOI) except at fast rate; • appear to be a constant proportion of the period which does not differ among age groups of neurologically intact non-rhythm experts; • do not appear to be significantly affected by tapping, though in ‘our’ rhythm experts, it tended to decrease sensitivity, while in some elderly individuals, it actually increased it (i.e., improved PS detection performance). Conclusions • Musical or ‘rhythmic dance’ expertise appear to improve sensitivity to a phase-shift irregularity.Q. Does that hold for a ‘ period’ one? • PS sensitivity as afunction of tempiobeys Weber’s law and doesnot appear to be affectedby age. • The non-interference of error detection (through Yes/No judgement) and correction (through synchronization) tasks is consistent with their being mediated by specialized(not to imply independent) underlying neural circuitries (to a certain extent), one (“The What” or ‘sensation for perception’) largely responsible for ‘conscious’ or attentionally-driven perceptual decisions and another (“The How” or ‘sensation for action’) critical for efficient audio-guided actions through largely ‘unconscious’ and pre-attentive sensorimotor mechanisms.

22. Summary of Results, Conclusions & Further Questions: 1. Perceptual Motor Error correction (from CF’s) suggest that: • All adults up to 75 years of age show CF’s up to the standards of Bruno Repp’s expert tappers! • As for the elderly participants (76+), they: • Largely show ‘normal’ CF’s, though some fail to return to their pre-shift baseline within the post-shift period (new baseline) for just detectable or clearly detectable PS. This was particularly true at their fast rate (600-ms IOI), which is actually the most comfortable for most ‘younger’ people. At that ‘fast’ rate, many also fail to show an overshoot at T+1 and do not correct faster for ‘supra’ than ‘subli’ PS (on average actually the reverse pattern) • Their best performance is at the slow rate of 1.11 Hz (900-ms IOI. Conclusions • Non rhythm experts are as good as rhythm experts in PS correction. This is consistent with it being largely an ‘automatic’ process (as claimed by Repp), independent of differences in attentionally-driven and/or cognitive expectations such as those that might arise from extensive musical expertise. • Overall, elderly show : • ‘normal’ timing error correction. • Are we coming back to the Slowing of the clock’ with aging??

23. YES: the clock is ticking…but what about the other timing measures Wait a minute… You (or your results) seem to say that a 90 year old healthy elderly is tapping just as well as a 19 year old (at least on our error detection and correction measures), but aren’t your ‘other measures’ (preferred and fastest rate and time estimation through the mean IRI for target rates of 0.5 and 1 second) suggesting ‘some deficits in timing’? , Are not the clearly slower ‘preferred rate’, ‘fastest rate’ as well as large overestimation (i.e., impaired absolute estimation of the 2 target time intervals despite largely maintaining their ‘relative timing) all converging evidence for a slowing of the baseline of an ‘internal clock’ with aging (or preferred period)? I’d like to open that for discussion THANKS for listening and participating!