+Behavioral and DTI

Studies on Normal

and Impaired

Learning of Musical

Structure

Psyche Loui

Wesleyan University

CogSci 2013

August 1, 2013

The world knows and loves music

Tone-deafness: a disorder of pitch

perception and action

Congenital amusia

Inability to sing in tune

Incidence: 4 – 17%

Montreal Battery of

Evaluation for Amusia

Inability to discriminate pitch

>1 semitone threshold

(musicianbrain.com/pitchtes

t)

What is the source of musical

knowledge?

Frequency

Probability

PitchHarmony

Melody

Perception

Existing musical systems confound learning

with memory

Test learning with new frequencies &

probabilities

New musical systemTone-deafness

We need a system to assess

implicit music learning

Bohlen-Pierce

A new tuning system – the BP scale

F = 220 * 2 n/12

F = 220 * 3 n/13

200

300

400

500

600

700

0 1 2 3 4 5 6 7 8 9 10 11 12 13

increments (n)

fre

qu

en

cy (

Hz)

Western

Loui, Wessel, & Hudson Kam, 2010, Music Perception

The BP scale can form chords

200

300

400

500

600

700

0 1 2 3 4 5 6 7 8 9 10 11 12 13

increments (n)

fre

qu

en

cy (

Hz)

F = 220 * 3 n/13

Bohlen-Pierce

3 : 5 : 7

Loui, Wessel, & Hudson Kam, 2010, Music Perception

Composing in the Bohlen-Pierce

scale

10 7 10 10

6 4 7 6

0 0 3 0

F = 220 * 3 n/13

Krumhansl, 1987;

Loui, Wessel, & Hudson Kam, 2010, Music Perception

Composing melody from harmony –

applying a finite-state grammar

10 7 10 10

6 4 7 6

0 0 3 0

Loui, Wessel, & Hudson Kam, 2010, Music Perception

Melody: 6 4 7 7 7 6 10 10

10 7 10 10

6 4 7 6

0 0 3 0

Composing melody from harmony –

applying a finite-state grammar

Loui, Wessel, & Hudson Kam, 2010, Music Perception.

10

Can we learn the B-P scale?

General design of behavioral studies:

1. PRE-TEST

assess baseline

2. EXPOSURE to melodies in one grammar

~30 minutes

3. POST-TESTS

assess learning

Learning a musical system:

Probability sensitivity

Can we remember old melodies?

2-AFC test of recognition

Can we learn new melodies?

2-AFC test of generalization

Double dissociation between learning

and memory

No. of melodies

12740100No. of repetitions

5 10 15 400

40%

50%

60%

70%

80%

90%

100%

Pe

rce

nt

Co

rre

ct

0

0.2

0.4

0.6

0.8

1

1.2

Diffe

ren

ce

in ra

ting

(fam

iliar -

un

fam

iliar)

recognition

generalization

Loui & Wessel, 2008Loui, Wessel & Hudson Kam, 2010

Disrupting harmony – the forced

octave scale

0 1 2 3 4 5 6 7 8 9 10 11 12 13

Increments (n)

0 1 2 3 4 5 6 7 8 9 10 11 12 13

200

300

400

500

600

700

Fre

que

ncy (

Hz)

200

300

400

500

600

700 Western scale: F = 220 * 2 n/12

B-P scale: F = 220 * 3 n/13

Forced-octave scale: F = 220 * 2 n/13

3 : 5 : 7

3:4.13:5.11

Loui, 2012, TopiCS

Generalization

Disrupting melody – eliminating

select transitional probabilities

10 10 7 10

6 7 4 6

0 3 0 0

Loui, 2012, TopiCS

Generalization

Mechanisms enabling generalization in musical AGL depend on transitional probabilities.

Learning a new musical system:

Frequency sensitivity Can we learn to expect frequent tones?

Probe tone ratings test

Probe tone profiles reflect frequencies of compositions

Krumhansl, 1990

Pre-exposure probe tone ratings

1

2

3

4

5

6

7

0 1 2 3 4 5 6 7 8 9 10 11 12

Probe tone

Ra

tin

g

0

200

400

600

800

1000

1200

Rating

Exposure

Fre

qu

en

cy o

f exp

osu

re

F = 220* 3n/13

Loui, Wessel & Hudson Kam, 2010, Music Perception

Post-exposure probe tone ratings

1

2

3

4

5

6

7

0 1 2 3 4 5 6 7 8 9 10 11 12

Probe tone

Ra

tin

g

0

200

400

600

800

1000

1200

Rating

Exposure

Fre

qu

en

cy o

f exp

osu

re

Loui, Wessel & Hudson Kam, 2010, Music Perception

Correlating ratings with exposure

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

Pre

Co

rre

latio

n (

r)

Post

ExposureLoui, Wessel & Hudson Kam, 2010, Music Perception

**

** p <

0.01

Participants: 15 tone-deaf, 20 control

Matched for age, sex, number of years of musical training

Pre-test 30-min. exposure Post-test Pre- vs. Post-Exposure Tone-deaf vs. Controls

Probe tone test: Melody Tone Probe tone profiles reflect frequencies in musical

compositions (Krumhansl 1990)

Statistical learning in tone-deaf individuals

(In progress)

Jan Iyer

Ratings: Controls

0

200

400

600

800

1000

1200

1

2

3

4

5

6

7

0 1 2 3 4 5 6 7 8 9 10 11 12

Exp

osu

re F

req

ue

nc

y

Ra

tin

gs

Probe Tone

Pre-

Exposure

Ratings

* Error bars represent

between-subject

standard errors for all

graphs

Post-

Exposure …

Ratings: Tone-deaf

0

200

400

600

800

1000

1200

1

2

3

4

5

6

7

0 1 2 3 4 5 6 7 8 9 10 11 12

Exp

osu

re F

req

ue

nc

y

Ra

tin

g

Probe Tone

Pre-Exposure

Ratings

Exposure

Post-Exposure

Ratings

-0.1

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

Control Tonedeaf

r-v

alu

e (

ratin

gs

vs.

exp

osu

re)

Pre-Exposure

Post-Exposure

*

Disrupted frequency learning in the

tone-deaf

*

* *

* p < 0.05

** p = 0.001

MBEA (scale score) correlates with

probe tone learning

-0.2

0

0.2

0.4

0.6

0.8

1

10 15 20 25 30Po

st-E

xp

osu

re P

rob

e

Ton

e C

orr

ela

tio

n (

r)

MBEA 2 (Contour) Score

r=0.18

-0.2

0

0.2

0.4

0.6

0.8

1

10 15 20 25 30Po

st-E

xp

osu

re P

rob

e

Ton

e C

orr

ela

tio

n (

r)

MBEA 3 (Interval) Score

r=0.15

-0.2

0

0.2

0.4

0.6

0.8

1

10 15 20 25 30

Po

st-E

xp

osu

re

Pro

be

To

ne

Co

rre

latio

n (

r)

r=0.36

(p<0.05)

Average of first three MBEA Scores

-0.2

0

0.2

0.4

0.6

0.8

1

10 20 30 40

Po

st-E

xp

osu

re

Pro

be

To

ne

co

rre

latio

n (

r)

r=0.45

(p<0.01)

MBEA 1 (Scale) Score

Loui & Schlaug, 2012, ANYAS

What are the neural substrates

of music learning?

STG IFG

Superior Temporal Gyrus (STG)

Inferior Frontal Gyrus (IFG)Mandell et al, 2007; Hyde et al, 2007

Diffusion tensor imaging

Tone-deafness – regions of interest

STG IFG MTG

Loui, Alsop, & Schlaug, 2009, Journal of Neuroscience

Superior AF Inferior AF

Control Tone-deaf

Normal vs. tone-deaf AFs

Loui, Alsop, & Schlaug, 2009, Journal of Neuroscience

Tract volume reflects individual

differences in learning

Volume of right ventral arcuate

fasciculus is correlated with

generalization score, but not with

recognition score.

r = 0.53, p = 0.03

0

5

10

15

20

25

0 0.5 1 1.5

RIF

G –

RM

TG

Tra

ct

vo

lum

e (

10

3m

m3)

Generalization (proportion correct)

Loui, Li, & Schlaug (2011) NeuroImage

r = 0.054, n.s.

0

5

10

15

20

25

0 0.5 1

Recognition(proportion correct)

Crucial junction of arcuate fasciculus

predicts learning behavior

Search for Fractional Anisotropy correlates of

generalization performance

FA (white matter integrity) of temporal-parietal junction

predicts individual differences in pitch-related learning.

p < 0.05 FWE

Loui, Li, & Schlaug (2011) NeuroImage

Behavioral implications of individual

differences in structural connectivity in

statistical learning

Normal Tone-deaf

Tracts from right STG

Loui, Alsop, & Schlaug, 2009, Journal of Neuroscience

Summary

Frequency ProbabilityPitch

Experiments now available for

download

http://figshare.com/articles/Bohlen_Pierc

e_scale_artificial_grammar_learning_expe

riment/75772

Also at

http://psycheloui.com/publications/down

loads

Max/MSP format

Several versions with melodies included

AcknowledgementsGottfried Schlaug

BIDMC, HMS

Music and Neuroimaging Lab

(http://musicianbrain.com)

Katy Abel

Rob Ellis

Anja Hohmann

Jan Iyer

Charles Li

Berit Lindau

Christoph Mathys

Sang-Hee Min

Matthew Sachs

Catherine Wan

Jasmine Wang

Anna Zamm

Xin Zheng

David Alsop

BIDMC, HMS

Carol Krumhansl

Cornell University

University of California at Berkeley

David Wessel

Center for New Music & Audio Technologies

Erv Hafter

Auditory Perception Lab

Carla Hudson Kam

Language & Learning Lab

Bob Knight

Helen Wills Neuroscience Institute

Take-home

Much of what we know and love about music is acquired

via statistical sensitivity to the frequency and probability

of occurrence of events in the auditory environment.

This statistical learning mechanism relies on intact white

matter connectivity between temporal and frontal lobe

regions, and may subserve multiple auditory-motor functions including language as well as music.