Neurosciences Fonctionnelles

Techniques et Méthodes (I)

[Illustrations]

Pr H. Sequeira

Univ. de Lille I et CNRS (Lille II)

Master I Psychologie, Option Neurosciences

Septembre 2012

IBRO

Neurologie

* Mesures Centrales: précision temporelle, spatiale,…

Magnetoencephalographie (MEG)

Quelle précision …? Spatiale … temporelle …Invasives vs non invasives …

B. Renault, 2006

Mesures Périphériques: globales, intégratives …

Enteric

nervous

system

Lane et al (2009)

A.A. ElectrodermalElectrodermal measures and sweatingmeasures and sweating

* Electrodermal Activity (EDA).

Recording EDA : assess variations of the central nervous activity throughelectrodes located on the skin of fingers

* EDA ?

1/ changes in the electrical properties of the skin ;

Eccrine glands ?

Hypodermis : palmar and plantar regions

Sweat ductSweat duct

StratumStratumcorneumcorneum

Dermo Dermo epidermal epidermal jonctionjonction

… h

yp

od

erm

is d

erm

is ep

iderm

is…

h

yp

od

erm

is d

erm

is ep

iderm

is

EccrineEccrineglandgland

… h

yp

od

erm

is d

erm

is ep

iderm

is…

h

yp

od

erm

is d

erm

is ep

iderm

is

Section of glabrous skin of sole (Sequeira and Roy, 1997; modified Section of glabrous skin of sole (Sequeira and Roy, 1997; modified

from Fowles, 1996)from Fowles, 1996)

An illustration :

Kobayashi et al (2003)

* Neuroanatomy … neurophysiology

Innervation of a human sweat gland by Innervation of a human sweat gland by sympatheticsympathetic varicose varicose

fibersfibers immunoreactive for calcitonin geneimmunoreactive for calcitonin gene--related peptiderelated peptide

(Gibbins, 1997).(Gibbins, 1997).

Sympathetic fibers ?

Preganglionic fibers

Postganglionic fibers

Preganglionic fibers

Spinal Cord

SG

Preganglionic fibers

Postganglionic fibers

Preganglionic fibers

Spinal Cord

SG

X

X

XX -- local atropine : local atropine : suppression of EDAsuppression of EDA but blood flow response is not;but blood flow response is not;XX -- ablation of sympathetic ganglia ablation of sympathetic ganglia suppresses EDA;;

Bursts of skin nerve Bursts of skin nerve sympathetic activity,sympathetic activity,plethysmogram and plethysmogram and skin skin

Relation : sympathetic fibers, eccrine glands and EDA.Relation : sympathetic fibers, eccrine glands and EDA.

plethysmogram and plethysmogram and skin skin resistanceresistance elicited by a elicited by a sudden shoutsudden shout (left) and (left) and deep inspirationdeep inspiration (right) in (right) in median nerve in human. median nerve in human.

(Wallin and Fagius, 1986).(Wallin and Fagius, 1986).

Taisne, Kobayashi, Mandai, Kimura and Sequeira (2008)

B.3 Characteristics of EDA

EDA, whatever the technique, two main components : - electrodermal level

- electrodermal responses.

Local Cutaneous Temperature : Local Cutaneous Temperature : EDA amplitudeEDA amplitude

Reticular formationReticular formation Peripheral nervePeripheral nerve

stimulationstimulation

Ba-M 'Hamed-Benis, S., Ciancia, F., Delerm, B., Roy, J.C., Sequeira, H. (1986)

Local Cutaneous Temperature : Local Cutaneous Temperature : EDA latencyEDA latency

Ba-M 'Hamed-Benis, S., Ciancia, F., Delerm, B., Roy, J.C.,

Sequeira, H. (1986)

C.2 Central mechanismsC.2 Central mechanisms

1

* Spinal integration* Spinal integration

* Reticular control* Reticular control

RAS

RAS : reticular activating system

RIS : reticular inhibiting system

+ - +

RIS

Sweat glandsSPNSPN

RAS

RIS

Roy, Sequeira, Delerm (1993).