EDA

Question 1

What are the 2 main layers of skin?

How does skin maintain heat?

Answer 1

Dermis: outer, five cellular layers
Epidermis: sweat glands and hair follicles
Also hypodermic containing secretory portions of sweat glands

Constriction of blood vessels and philoerection

Question 2

What EDA did Fere observe and what technique?

Answer 2

Changed electrical activity from phys/em stimuli
SCR/ACL & SRR (exosomatic)

Technique: passed current between 2 sites, detect change when stem presented PGR-> GSR

Question 3

What is Tarchanoff’s technique/what does it relate to?

Answer 3

SPR/SPL (endosomatic)

Technique: no external current- natural differences between 2 areas- change when stimulus presented

Question 4

What does EDA measure?

Answer 4

Complex innervation of sweat gland activity

Question 5

What is the distribution and makeup of eccrine glands?

How are they innervated?

Answer 5

Wide, palms/soles, 2-5m
Tubular w duct to surface, contain secretory portion= coils that open to pore on surface

Secretory portion- nerve supply via cholinergic fibres from SNS but transmitted by acetylcholine (which is usually PNS)

Question 6

What is the difference between phasic and tonic measures?

What sort of electrodes are used to measure EDA?

Answer 6

Phasic response: momentary, from simulation
Tonic level: relatively stable

Non-polarising. Recommend Ag/AgCl with Kcl or NaCl as electrolyte

Question 7

What units are used for measuring skin conductance and what techniques are used?

Answer 7

Trad: mho, Now: microsiemen uS

1. Constant voltage: hold voltage across electrodes constant- current varies with conductance change (ink writer)
2. Constant current: potential difference varies with resistance

Question 8

What unit is used to measure skin potential and how is it measured?

Answer 8

• millivolts (mV) biphasic, or uniphasic

Unipolar placement, active and reference (on braided skin), Stimulus -> Change SP
DC amplifier measures change

Question 9

What is the OR and what is it based on?

Answer 9

Marked response decrement with stimulus repetition measured by phasic EDA
Based on pavlov’s “what is it?” reflex-> immediate response from env. change

Question 10

What is Sokolov’s mechanism forth OR?

Answer 10

Repeated stem-> neuronal model of stimulus
Discrepancy between stimulus and model produces OR (enhances perception)
Output of comparison amplified by arousal

Question 11

What is Sokolov’s model largely based on and what are his 3 determinants of OR?

Answer 11

Missing-stimulus effect- as after many reps, non-rep produces OR

Novelty, intensity and significance