Response Time
CHAPTER 5: FUNCTIONAL CORRELATES OF LEARNING TO READ AND PLAY MUSIC
A longitudinal Junctional magnetic resonance imaging (fMRI) study was conducted to measure changes in brain function associated m th learning to read music and plcy the keyboard. Twelve musically naïve participants were taught to a standardised basic level (Grade 1, Associated Board, U.K) in music theory and practical keyboard skills. Three conditions were used: reading music for melody, reading music for rhythm and an implicit music reading condition. A factorial blocked design was implemented in which each condition had experimental and control blocks, both before and after training. The interaction of training (post-training — pre-training) and trial-type (experimental — control) for the melody reading condition showed activation in right superior parietal cortex. In the implicit music reading condition, in which musical notation was present in the experimental block, but irrelevant for task performance, activations were seen in left supramarginal g)rus. A region of interest analysis revealed that the right superior parietal activation seen in the melody reading condition was also present in the implicit music reading condition. The findings suggest that training forges an automatic association between musical notation and its related musical response.
5.1 INTRODUCTIO N_____________________________________________________
W hen a child or adult starts to play the keyboard, a significant part o f the initial
musical training is devoted to learning to read musical notation. Musical pieces which, at
first sight, appear meaningless in their written form, will eventually be translated into a
recognisable melody. Just as written language becomes meaningful and even compelling to
read, so does musical notation. But the process by which this occurs is not well
understood. The present experiment aimed to establish which brain areas showed
learning-related changes in activity after musical training.
The acquisition o f musical literacy is more amenable to study than the acquisition
o f language literacy, from both a psychological and neurological position. In the developed
world Literacy rates are high, but investigations into Literacy acquisition are therefore
difficult. Ln contrast, musical literacy rates are low, yet many individuals are motivated to
short period o f training. Thus the cognitive and neurological profiles o f an individual can
be measured, before and after musical literacy acquisition.
The present study investigates three aspects o f music reading. The first two
correspond to the decoding o f the main components o f musical notation - pitch and
rhythm. Although in skilled music reading, musical notation is read for both pitch and
rhythm simultaneously, it is likely that each aspect makes quite different demands on the
brain. Inform ation specifying which note should be played is contained in its spatial
position on the musical stave. Information specifying how long the note should be held is
conveyed by the note's visual appearance (e.g. whether it is filled, whether it has a tail
attached to the stem or a dot placed beside it).
Thus learning-related changes in response to melody and rhythm reading are
measured separately, in two different conditions. In the third condition, an implicit music
reading task is used, in which musical notation was present but irrelevant for the task. The
question asked was whether newly acquired knowledge, concerning the meaning o f musical
notation, is automatically evoked.
There are several conceptual and methodological issues that pertain to brain
imaging studies o f development and learning. Poldrack (Poldrack, 2000) provides a review
o f several o f these, citing factors related to changes in performance and the inherently
temporal nature o f learning and development which may confound interpretation o f
imaging results. For example, changes in performance with skill learning may result in
different amounts o f time spent performing the task. However, neural activation is known
to differ as a function o f time on task, the so-called duty-cycle effect (D' Esposito, Zarahn,
made to match time on task before and after training by having participants perform the
explicit music reading conditions using a num ber to finger mapping, pre-training, and a
note to finger mapping post-training. In the implicit music reading task, performance was
at ceiling both pre-training and post-training, so duty-cycle effects did not arise. Since
participants performed the explicit tasks differently, pre- and post-training, any activation
changes could not be strictly interpreted as arising from an effect o f learning per se.
Instead, they may be interpreted to arise from a combination o f task-related and learning-
related differences. However, since the implicit music reading task was identical pre
training and post-training, activation differences in either o f the explicit tasks which were
common to the implicit condition could be interpreted as learning-related, and not merely
task-related. A group o f non-leamers (participants who could not read music or play an
instrument and did not take part in the training) were also scanned twice, to provide a
control for non-specific changes in activation which may relate to factors such as increased
familiarity with the scanning environment during the second scanning session,
physiological differences in arousal, differences in participants' head position or slight
variations in scanner hardware characteristics (McGonigle, Howseman, Athwal, Friston,
Frackowiak & Holmes, 2000).
Experiment 2 o f Chapter 2 and experiment 3 o f Chapter 3 describe the behavioural
correlates o f musical literacy acquisition. In the experiment described below, fMRI is used
to measure the brain correlates o f musical literacy in these same participants.
5.1.1.1
Method
Two groups (Learners and Non-learners), each comprising 12 participants, were
used. O ne group (the learners) responded to an advertisement asking for individuals with
no music reading or playing experience to take part in two scanning sessions and undertake
three m onths o f musical training. The second group (the non-leamers) responded to a
different advertisement which asked for individuals who were similarly lacking in musical
experience to take part in two scanning sessions with no training element in-between.
Participants were screened for previous musical training (either formal or self-taught) using
a self-report questionnaire. A second stage o f selection required participants to attem pt to
play a set o f simple melodies on a keyboard, using the right hand. The starting point o f
each melody was given before the start o f each trial. N one o f the participants showed any
signs o f previous musical training, either via self-report or via their performance on a
simple music reading task. Both groups comprised 6 females and 6 males and the average
ages o f the learner and non-leamer groups were 34 (range: 24-53) and 26 (range: 19-30)
respectively.
5.1.1.1.2
M u sical Training
See section Chapter 2, section 2.1.2.1.2.
5.1.1.1.3
M easu rem ent o f Skill A cqu isition
After the training was complete, an independent external music teacher examined
participants individually on keyboard skills (scales, a prepared piece from the Grade 1
syllabus and Grade 1 sight reading). Participants also sat a Grade 1 music Theory
examination (see Chapter 2, section 2.1.2.1.2 for a description o f the Grade 1 keyboard and
theory requirements). A more cognitive measure o f music reading ability was obtained
encoding o f musical notation was measured by ascertaining the degree to which musical
notation interfered with performance o f a primary num ber to finger mapping task.
5.1.1.1.4
Tasks
3.1.1.1 A. 1
Melody Condition
Participants were required to produce a series o f keypresses in response to the
appearance o f a sequence o f five musical notes o f different pitch (Figure 5-1). Pre-training,
these musical notes were labelled with numbers (1-5), enabling participants to make a
simple num ber to finger mapping. After training, these labels were replaced with nonsense
symbols, requiring participants to decode the musical notes using their newly acquired
musical literacy. The non-learners, who could not read music, perform ed the task using
numbers during both scanning sessions. In order to minimise the rhythmic element o f
music reading, all notes were crotchets (quarter notes) and participants were instructed to
make the keypresses at an even pace o f their own choosing. Both the pre-training and the
post-training tasks incorporated a control for low-level visual and m otor elements. The
appearance o f an ascending or descending pattern o f notes prom pted participants to
execute a simple ramp sequence o f keypresses from the thumb to the Little finger
(ascending) or vice versa (descending). Thus stimulus and response elements were
maintained across experimental, non-ramp trials and control, ramp trials but the control
Pre-training Post-training
experimental
control
Figure 5-1. Learning to Read and Play Music - Stimuli: Melody.
Example o f stimuli. Pre-training, participants performed a number to finger mapping. Experimental trials w ere unpredictable in their specified motor response compared to control trials which specified an ascending or descending sequence o f responses. Post-training, the sam e stimuli w ere used but nonsense sym bols replaced the numbers so participants now performed a note to finger mapping. Participants in the non-leam er group used a number to finger mapping for both the 1st and 2nd scans.