EEG Alpha Power During Perception of Music

1
EEG Alpha Power During Perception of Music
Visual Art Musicians Versus Non-Musicians

M.J. Ferry J.A. Dale
Program 752.22 Neuroscience Psychology
Departments Allegheny College, Meadville PA
16335, USA
Results
Sample Stimuli
Abstract
The EEG, alpha band power during artistic
stimuli (selected Gauguin paintings) and musical
stimuli (selections from Schumann) was compared
in 12 musicians and 10 non-musicians, college
students. The stimuli had been previously rated
as both positive and negative in emotional
valence in a pilot study. Two items of each
valence were employed musical stimuli were
presented for 30 sec periods and visual stimuli
were presented for 15 sec periods based on pilot
data responses. EEG was recorded using a
multi-electrode array cap connected to a NuScan
amplification system and analyzed with reduction
routines and the avoidance of readily apparent
artifacts. Musicians showed higher alpha band
power in the left frontal lobe (FP1) than
non-musicians for both positive and negative
stimuli (for art and music) and this trend neared
significance in the right frontal lobe (FP2) as
well (0.05ltplt0.10). Also in the left frontal
area, a trend of higher alpha power for musicians
as compared with non-musicians approached
significance at FT7 (0.05ltplt0.10). Overall,
there was a trend of higher alpha power for
musicians compared with non-musicians at all
electrode positions. No differences were noted
as a function of the valence of the emotionality
of the pieces. It is possible that the musicians
required less cognitive effort than the
non-musicians to process the stimuli in the
frontal lobes.
Art Paul Gauguin
Music Robert Schumann

• Kinderszenen, Opus 15 - 1838
• (Scenes from Childhood)
• Name of Movements Used
• Happy Enough
• Knight of the Hobby-Horse
• Almost Too Serious
• Child Fallen Asleep

Musicians showed a trend of higher mean alpha
band power at all electrode conditions (for all
experimental conditions) as compared with
non-musicians. Note that this trend appears to
be most prominent in the frontal area. The mean
alpha band power for musicians and non-musicians
at each electrode location is shown with the
standard error of the mean illustrated through
the error bars for each group.
A significant higher alpha band power mean at
position FP1 from baseline to positive and
negative stimuli conditions occurred for
musicians but not non-musicians. Error bars
represent the standard error of the mean for each
group.
Schumanns Happy Enough was rated as evoking
happiness by 90 of raters in a pilot study used
to select stimuli for the present study and
received a rating of 4.0 out of 5 for the
emotional intensity rating.
Gauguins The Brooding Woman (1891) was rated as
evoking sadness by 70 of raters in a pilot study
used to select stimuli for the present study and
received a rating of 3.8 out of 5 for the
emotional intensity rating.
.
Equipment
Purpose
Despite the commonly supported belief that the
right hemisphere is the location of the brains
musical center (Carlson, 2001), several studies
have demonstrated a difference in hemispheric
lateralization depending on the musical training
background of the individuals tested (Marinoni,
et al, 2000, Bhattacharya, et al, 2001). The
present study hoped to investigate whether or not
the hemispheric lateralization effect would be
replicated and whether or not musicians and
non-musicians EEG would differ from each other
while processing music. Would differences
between musicians and non-musicians extend to the
processing of visual art? Additionally, would
the emotional valence of the stimuli have an
effect on the EEG of the two groups?
Approaching significance, alpha band power at FT7
(left fronto-temporal lobe) was lower for
musicians looking at art that was negative as
compared to positive art. Musicians also showed
the trend of higher alpha band power for positive
and negative music from the baseline condition.
Musicians demonstrated greater mean alpha band
power than non-musicians at FT7 during the
processing of both positive and negative music
and art.
Alpha band power at FT7 (left fronto-temporal
lobe) approached significance. As seen,
relatively little change occurred for the mean
alpha band power of non-musicians from baseline
to stimuli conditions for both music and art.


Methods
Participants
At left, the Neuroscan Labs NuAmps 7181,
18-electrode recording system and at right, a
Neuroscan Quik-Cap, were used to record cortical
EEG at 32 electrode locations Compumedics
Neuroscan? (2003). http//www.neuroscan.com/produ
ct.sstg?id31pic1
Preliminary Study
Twenty-two participants were recruited from the
student population at Allegheny College (females
N12, males N10). Half were classified as
musicians. Musicians - self-described as
musicians, currently
studying/performing music, and having a
minimum of five years of musical
training Non-musicians - self-described as
non-musicians, minimal or no
formal musical training

• Twenty randomly recruited participants viewed a
  PowerPoint presentation of twelve pictures of
  Gauguins art and a separate PowerPoint
  presentation of the thirteen movements of
  Schumanns Scenes From Childhood, Op. 15 and
  provided subjective ratings for familiarity, the
  emotion associated with each stimulus, and the
  intensity of that emotion.
• Inter-rater reliability was calculated and the
  top four stimuli were determined for both the
  musical and visual stimuli

Hypotheses
Conclusions
It was hypothesized musicians would show left
hemisphere activation and non-musicians would
show right hemisphere dominance during the
perception of music. The same lateralization
effect between musicians and non-musicians was
expected to extend to the viewing of artistic
paintings. Additionally, stimuli of differing
emotional valence were used with positive stimuli
hypothesized to activate the left frontal lobe
and negative stimuli expected to activate the
right frontal lobe.
A hemispheric laterality effect was found between
the musicians and non-musicians for the
processing of music and this difference extended
to the processing of art 1. Musicians differed
from non-musicians in that they had higher alpha
band power, particularly in the left frontal lobe
while reviewing musical and also artistic
stimuli. 2. This hemispheric laterality
difference in the processing of expressive music
and art occurred regardless of the emotional
valence of the stimuli. In future studies, the
stimuli might be used to induce mood rather than
having the participant merely rate the
emotionality of each stimulus without first
feeling its emotional quality. 3. Musicians
showed a trend of higher alpha levels at all
twelve electrode locations analyzed as compared
with non-musicians.
Procedure

• Thirty-sec. musical passages (binaurally
  presented via headphones) and fifteen-sec. of
  viewing for each piece of visual art were
  presented using two separate PowerPoint
  presentations displayed on a desktop computer.
• The Neuroscan Labs NuAmps 7181, 18-electrode
  recording system was used to record EEG (at
  FP1/2, F3/4, CZ, FZ, FPZ, O1/2, T3/4, FT7/8)
  using the Neuro-Scan multi-electrode array cap.
  Separate button electrodes were used to assess
  EMG activity resulting from eye movements. A
  Schmidt detector was used to signal three equally
  time-spaced epochs during each stimulus
  presentation. EEG was amplified using a
  Coulbourne bioamplifier.
• Following each stimulus presentation (30-sec. for
  music, 15-sec. for art) the participant was
  allotted 60-sec. to respond to each stimulus
  using a written survey. Alpha band power was
  compared for the thirteen electrode positions for
  both musicians and non-musicians using the
  statistical analysis software, SPSS.