the effects of rtms on primary motor cortex: the link between action and language ( preliminary...

The effects of rTMS on primary motor

cortex: the link between

action and language(preliminary results)

Claudia RepettoDepartment of Psychology,

Catholic University of Sacred Heart, Milan, Italy

EMBODIED LANGUAGE New College Oxford

26-28 September 2011

RATIONAL

EMBODIED COGNITIONEMBODIED COGNITION

EMBODIED SEMANTICSEMBODIED SEMANTICS

Experimental dataVerbs indicating actions performed with different body parts activate the portions of the premotor cortex involved in the

real action

Experimental dataVerbs indicating actions performed with different body parts activate the portions of the premotor cortex involved in the

real action

(Hauk, Johnsrude, & Pulvermüller, 2004)

Experimental dataVerbs indicating actions performed with different body parts activate the portions of the premotor cortex involved in the

real action

(Hauk, Johnsrude, & Pulvermüller, 2004) (Tettamanti et al., 2005)

Experimental dataSeveral studies indicate that even the primary motor

cortex (M1) is involved in language processing, but results are sometimes contrasting

VS

Tools: Tasks:

Birra…Firra...

Buffo…Biffo

Birra…Firra...

Buffo…Biffo

birra

biffobuffo

firra

(Fadiga et al., 2002)

o Increase of MEP recorded from the listeners' tongue muscles when the presented words strongly involve, when pronounced, tongue movements

o The processing of verbs indicating actions performed with different body parts modulate the activity of the portions of the primary motor cortex (M1) involved in the real action

(Buccino et al., 2005)

he played the piano

he jumped the rope

he loved his wife

o The comprehension of effector specific action word meanings did not elicit preferential activity corresponding to the somatotopic organisation of effectors in either primary or premotor cortex

(Postle et al., 2008)

But on the other hand…..

+ +

GOALS OF THE EXPERIMENT

METHOD

10 students, 5 males and 5 females (age: 21-46; mean: 28.7; st. dev.: 9.57 education:16-20; mean: 16.7; st. dev.:1.25)

Low-frequency rTMS

Verbs comprehension (semantic judgment)

MATERIAL

24 ACTION VERBS + 24 ABSTRACT

VERBS

applaudire (to clap)abbottonare (to button)firmare (to sign)…….

apprezzare (to appreciate)immaginare (to imagine)scordare (to forget)…….

MATERIAL

24 ACTION VERBS + 24 ABSTRACT

VERBS

48 items x 3 blocksi.e. firmavo-firmavi-firmava;scordavo-scordavi-scordava

TASK

++ firmava2 sec 5 sec ++

5 minutes

PROCEDURE

Practice session

task

Off-line rTMS session over M1

task

45 min

PROCEDURE

Practice session

task

Off-line rTMS session over M1

task

45 min

PROCEDURE

Practice session

task

task

45 min

RIGHT M1

RIGHT HAND

PROCEDURE

Practice session

task

task

45 min

RIGHT M1

RIGHT HAND

LEFT HAND

LEFT M1

EXPERIMENTAL DESIGN

2(stimulation)

2(stimulation)

x

NOtms

M1

2(side)

2(side)

2(verbs)

2(verbs)

right

left

abstract

concrete

x

RESULTSo main effect of stimulation [F(1,9)= 55.11;p<0.001]

o main effect of verb [F(1,9)=38.708; p<0.001]

o interaction stimulation x verb [F(1,9)=11.272; p=0.008]

DISCUSSIONMethodological issues: variable “stimulation” not counterbalanced

?

Possible explanations… (to be completed…)

1. M1 is not involved the lower RTs post stimulation are due to a learning effect

1. M1 is not involved the lower RTs post stimulation are due to a learning effect

Control group: 18 students, comparable for age and education

NO effect of time [F(1,16)= 1.657; p= 0.216]

NO interaction time x verb [F(1,16)= 0.01; p=0.975]

Possible explanations… (to be completed…)

2. M1 is involved in different ways depending on the type of verb (action/abstract)

2. M1 is involved in different ways depending on the type of verb (action/abstract)

M1

Action verbs

Abstract verbs++ - -

-

++ +++

Possible explanations… (to be completed…)

2. M1 is involved in different ways depending on the type of verb (action/abstract)

2. M1 is involved in different ways depending on the type of verb (action/abstract)

M1

Action verbs slower RTs (with respect to the gain between baseline and post-tms with abstract verbs)

Abstract verbs “jump a step” faster RTs++ - -

-

++ +++

xx

See Papeo et al. (2009)

Future perspectives

o sample completion (with sessions counterbalanced)

to disambiguate between the hypothesis of involvment and non-involvment of M1

to investigate the different involvment during abstract vs action verbs processing

To interpret the complete set of data and give a contribution to the study of embodied language

claudia.repetto@unicatt.it

THANK YOU FOR YOUR ATTENTION!