Kluk, K.*, Tan, C.M.*, Gilpin, H.*, Fitt N.*, John, M.S.**, Picton, T.W.**

* Human Communication and Deafness Research Group,University of Manchester, Manchester,UK; **Rotman Research Institute, University of Toronto, Toronto, Canada

E-mail: karolina.kluk@manchester.ac.uk

MEASURING TRAINING-INDUCED AUDITORY PLASTICITY USING

AUDITORY STEADY-STATERESPONSES

INTRODUCTION

Kluk, K. and B.C. Moore, Dead regions in the cochlea and enhancement of frequency discrimination: Effects of audiogram slope, unilateral versus bilateral loss, and hearing-aid use. Hear Res, 2006. 222(1-2): p. 1-15.

Plasticity - re-mapping of the primary auditory cortex - may be induced by deprivation

INTRODUCTIONPlasticity - re-mapping of the primary auditory cortex - may be induced by deprivation or training.

EXPERIMENTAL DESIGN 

Normally-hearing, right-handed, non-musicians

R L

ASSRs

Day 1

L

Training

Days 2, 3, and 4

R

ASSRs

Day 5

1 2

EXPERIMENT 1 

R L

ASSRs Pitch Training ASSRs

L

100% AM41 & 45 Hz83 & 87 Hz

R L

1 2 kHz 1 kHz

Pure Tone70 dBSPL3 X 2 hours

the same as pre-training

EXPERIMENT 1 Pure Tone results

Training:3 x 2-hour sessions, 24 hours apart5000 presentations of pure tone at 1 kHz3AFC

Right 40 Hz

0 1000 2000

Res

pons

e am

plitu

de (n

V)

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16 Pre-trainingPost-training

EXPERIMENT 1 ASSR Amplitude

Right 80 Hz

Carrier Frequency (Hz)0 1000 2000

Res

pons

e A

mpl

itude

(nV

)

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16Left 80 Hz

Carrier Frequency (Hz)0 1000 2000

Res

pons

e A

mpl

itude

(nV

)

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

Left 40 Hz

0 1000 2000

Res

pons

e A

mpl

itude

(nV

)

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

1 2 4

EXPERIMENT 2 

R L

ASSRs FM Training ASSRs

L

MM :40 & 80 Hz

R L

2 kHz

FM Tone Modulatedat 10 Hz3 X 2 hours

1 2 4 kHz

the same as pre-training

EXPERIMENT 2 FM results

Training:3 x 2-hour sessions,

24 hours apart2- kHz FM tone modulated at 10-Hz3AFC

EXPERIMENT 2 ASSR Amplitude

1 2 4

EXPERIMENT 3 

R L

ASSRs AM Training ASSRs

R

100 % AM40 & 80 Hz

R L

2 kHz

AM Tone Modulated at4, 32, 128 Hz3 X 2 hours

1 2 4 kHz 1 2 4 1 2 4 kHz

the same as pre-training

EXPERIMENT 3 AM results

Training:3 x 2-hour sessions,

24 hours apart2- kHz AM tone4, 32, 128 Hz3AFC

4 Hz

32 Hz128 Hz

Left 40 Hz

Carrier frequncy (kHz)

1 2 41 2 4

Res

pons

e A

mpl

itude

(uV

)

0.0

0.1

0.2

0.3

0.4Pre-trainingPost-training

EXPERIMENT 3 ASSR Amplitude

 CONCLUSIONS

1. It is possible to measure training induced plasticity using ASSRs.

2.When Training using Pure Tones or Frequency Modulated Tones improvement on behavioural task is correlated with increased ASSR amplitude.

3.When training using Amplitude Modulated Tones there is no improvement on behavioural task nor an increase in ASSR amplitude.

 

 CONCLUSIONS 4. The increase of the ASSR amplitude after training

may be caused by the reorganization of the

primary auditory cortex and not by better

synchronization of neural firing.

 

Acknowledgements

• Members and students of Human Communication

and Deafness Research Group, Manchester, UK.

• Faculty of Human and Medical Sciences Start-up

Fund, The University of Manchester, UK

E-mail: karolina.kluk@manchester.ac.uk

Thank you !

E-mail: karolina.kluk@manchester.ac.uk