title: Monkeys time their pauses of movement and not their movement-kinematics during a synchronization-continuation rhythmic task.
abstract: A critical question in tapping behavior is to understand whether the temporal control is exerted on the duration and trajectory of the downward-upward hand movement or on the pause between hand movements. In the present study, we determined the duration of both the movement execution and pauses of monkeys performing a synchronization-continuation task (SCT), using the speed profile of their tapping behavior. We found a linear increase in the variance of pause-duration as a function of interval, while the variance of the motor implementation was relatively constant across intervals. In fact, 96% of the variability of the duration of a complete tapping cycle (pause + movement) was due to the variability of the pause duration. In addition, we performed a Bayesian model selection to determine the effect of interval duration (450-1,000 ms), serial-order (1-6 produced intervals), task phase (sensory cued or internally driven), and marker modality (auditory or visual) on the duration of the movement-pause and tapping movement. The results showed that the most important parameter used to successfully perform the SCT was the control of the pause duration. We also found that the kinematics of the tapping movements was concordant with a stereotyped ballistic control of the hand pressing the push-button. The present findings support the idea that monkeys used an explicit timing strategy to perform the SCT, where a dedicated timing mechanism controlled the duration of the pauses of movement, while also triggered the execution of fixed movements across each interval of the rhythmic sequence.
authors.affiliation: Unité Mathématiques et Informatique Appliquées, Institut National de la Recherche Agronomique, Paris, France;
authors.forename: Sophie
authors.initials: S
authors.lastname: Donnet
authors.affiliation: Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, México;
authors.forename: Ramon
authors.initials: R
authors.lastname: Bartolo
authors.affiliation: Instituto de Engenharia Electrónica e Telemática de Aveiro/Departamento de Electrónica, Telecomunicações e Informática, Universidade de Aveiro, Aveiro, Portugal; and.
authors.forename: José Maria
authors.initials: JM
authors.lastname: Fernandes
authors.affiliation: Department of Electrical and Computer Engineering, Faculty of Engineering, University of Porto/Instituto de Engenharia de Sistemas e Computadores Tecnologia e Ciência, Porto, Portugal.
authors.forename: João Paulo Silva
authors.initials: JP
authors.lastname: Cunha
authors.affiliation: Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, México;
authors.forename: Luis
authors.initials: L
authors.lastname: Prado
authors.affiliation: Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, México; hugomerchant@unam.mx.
authors.forename: Hugo
authors.initials: H
authors.lastname: Merchant
mesh_terms: D000161:Acoustic Stimulation; D000465:Algorithms; D000818:Animals; D001499:Bayes Theorem; D001696:Biomechanical Phenomena; D003463:Cues; D006225:Hand; D008253:Macaca mulatta; D008297:Male; D008960:Models, Psychological; D009048:Motor Skills; D010507:Periodicity; D010775:Photic Stimulation; D011597:Psychomotor Performance; D013647:Task Performance and Analysis; D013997:Time Factors; D014741:Video Recording
keywords: Rhesus monkey; interval timing; model testing; movement kinematics; time production