Bouncing Ball with a Uniformly Varying Velocity in a Metronome Synchronization Task

Summary

The purpose of this protocol is to introduce the application of a bouncing ball with a uniformly varying velocity in a metronome synchronization task.

Abstract

Sensorimotor synchronization (SMS), a fundamental human ability to coordinate movements with external rhythms, has long been thought to be modality specific. In the canonical metronome synchronization task that requires tapping a finger along with an isochronous sequence, a well-established finding is that synchronization is much more stable to an auditory sequence consisting of auditory tones than to a visual sequence consisting of visual flashes. However, recent studies have shown that periodically moving visual stimuli can substantially improve synchronization compared with visual flashes. In particular, synchronization of a visual bouncing ball that has a uniformly varying velocity was found to be not less stable than synchronization of auditory tones. Here, the current protocol describes the application of the bouncing ball with a uniformly varying velocity in a metronome synchronization task. The usage of the bouncing ball in sequences with different inter-onset intervals (IOI) is included. The representative results illustrate synchronization performance of the bouncing ball, as compared with the performances of auditory tones and visual flashes. Given its comparable synchronization performance to that of auditory tones, the bouncing ball is of particular importance for addressing the current research topic of whether modality-specific mechanisms underlay SMS.

Introduction

Sensorimotor synchronization (SMS) refers to the coordination of movements (e.g., finger taps) with an external rhythm, and is canonically studied using a simple metronome synchronization task in which the subject is required to tap a finger along with an isochronous sequence^1,2. The superiority of the auditory over visual modality in metronome synchronization has been established for over a century: synchronization is much more stable to an auditory sequence consisting of auditory tones (Figure 1A) than to a visual sequence consisting of visual flashes (

Protocol

This protocol was approved by the Institutional Review Board of Psychology Department of Sun Yat-Sen University.

NOTE: A custom program "BouncingBall"⁹ is provided for accomplishing this protocol. Extracting the file "BouncingBall.zip" generates a directory "BouncingBall", which contains auditory and visual stimuli files (see Section 1 below), a script "BouncingBall_run.m" for programming of stimulus presentation and response recording (see Section 2 below) and presenting stimuli and recording responses (see Section 3 below), and a script "BouncingBall_analyze.m" for programmin....

Results

One of the best-known results in SMS studies is that metronome synchronization is much more stable to an auditory sequence consisting of auditory tones than to a visual sequence consisting of visual flashes¹, suggesting modality-specific mechanisms of SMS². However, recent studies have shown that periodically moving visual stimuli can substantially improve synchronization compared to visual flashes^3,

Discussion

This protocol illustrates how to examine a bouncing ball with a uniformly varying velocity in a metronome synchronization task. Given its comparable synchronization performance to that of auditory tones, the bouncing ball is of particular importance for addressing the current research topic of whether SMS is modality specific.

The critical step in the current protocol is to introduce the uniformly varying velocity of the bouncing ball, and step-by-step instructions are provided to carry out t.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Psychtoolbox	http://psychtoolbox.org	3.0.12
MATLAB	MathWorks	7.11.0 (R2010b)
Adobe Photoshop	Adobe Systems	Adobe Photoshop CS6
computer monitor	AOC	G2460PQU/BR LCD
headphone	PHILIPS	SHM6500
computer keyboard	Dell	kb113t
smart phone	Apple	iphone6s
IBM SPSS Statistics	IBM	IBM SPSS Statistics 21