Uncovering Beat Deafness: Detecting Rhythm Disorders with Synchronized Finger Tapping and Perceptual Timing Tasks

Summary

Behavioral tasks that allow for the assessment of perceptual and sensorimotor timing abilities in the general population (i.e., non-musicians) are presented. Synchronization of finger tapping to the beat of an auditory stimuli and detecting rhythmic irregularities provides a means of uncovering rhythm disorders.

Abstract

A set of behavioral tasks for assessing perceptual and sensorimotor timing abilities in the general population (i.e., non-musicians) is presented here with the goal of uncovering rhythm disorders, such as beat deafness. Beat deafness is characterized by poor performance in perceiving durations in auditory rhythmic patterns or poor synchronization of movement with auditory rhythms (e.g., with musical beats). These tasks include the synchronization of finger tapping to the beat of simple and complex auditory stimuli and the detection of rhythmic irregularities (anisochrony detection task) embedded in the same stimuli. These tests, which are easy to administer, include an assessment of both perceptual and sensorimotor timing abilities under different conditions (e.g., beat rates and types of auditory material) and are based on the same auditory stimuli, ranging from a simple metronome to a complex musical excerpt. The analysis of synchronized tapping data is performed with circular statistics, which provide reliable measures of synchronization accuracy (e.g., the difference between the timing of the taps and the timing of the pacing stimuli) and consistency. Circular statistics on tapping data are particularly well-suited for detecting individual differences in the general population. Synchronized tapping and anisochrony detection are sensitive measures for identifying profiles of rhythm disorders and have been used with success to uncover cases of poor synchronization with spared perceptual timing. This systematic assessment of perceptual and sensorimotor timing can be extended to populations of patients with brain damage, neurodegenerative diseases (e.g., Parkinson’s disease), and developmental disorders (e.g., Attention Deficit Hyperactivity Disorder).

Introduction

Humans are particularly efficient at processing the duration of events occurring in their environment¹. In particular, the ability to perceive the beat of music or the regular ticking of a clock and the ability to move along with it (e.g., in dance or synchronized sports) is widespread in the general population (i.e., in individuals who have not received musical training)^2,3. These abilities are underpinned by a complex neuronal network involving cortical brain regions (e.g., the premotor cortex and the supplementary motor area) and subcortical structures, such as the basal ganglia and the cerebellum^4-7.

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Protocol

1. Synchronization Tasks

1. Preparation of Instruments:
   1. Connect a standard MIDI percussion instrument to the computer via a conventional MIDI interface.
      NOTE: Data acquisition is realized via a MIDI electronic percussion instrument. The device captures the exact timing of the finger taps during the motor synchronization tasks.
   2. Open the dedicated software for stimulus presentation and response recording.
      NOTE: The synchronization task is implemented using standard software for the presentation of audio material and recording of data from a digital MIDI musical instrument (with 1 msec precision).
2. So....

Results

The tasks described above have been used with success to characterize the timing abilities of individuals without musical training^2,34-36. In a recent representative study on beat-deafness², a group of 99 non-musicians (university students) were screened using two simple synchronization tasks. Participants synchronized their finger tapping with an isochronous sequence and a musical excerpt at a comfortable tempo (with an IOI/IBI of 600 msec). Ten of the participants showed particularly poor synchron.......

Discussion

The goal of the described method is to provide a set of tasks and analysis strategies to characterize the timing abilities of the majority of individuals and detect cases of beat deafness or poor synchronization. The critical steps of the protocol involve 1) the setup of the instruments used for stimulus presentation and collection of finger tapping data and subjects’ responses, 2) data collection using two sets of tasks (synchronization and rhythm perception), 3) analysis of synchronization data with circular stat.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Matlab	Mathworks		High-level language and interactive environment for numerical computation, visualization, and programming
MAX MSP	Cycling '74		Software for data acquisition from MIDI-controlled interfaces, and stimulation presentation
Presentation	Neurobehavioral Systems		Software for conducting experiments in experimental psychology. Allows precisely-times stimulus delivery and collection of behavioral responses.
Roland HPD- 10	Roland		Hand percussion pad (MIDI instrument)
EDIROL FA-66	Roland		MIDI interface to connect the MIDI instrument to the computer.