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Question 1

EEG electrode placement

Answer 1

10/20% method
- 10% - 4x20% - 10%
- 19 electrodes

Question 2

EEG Montage Types

Answer 2

System in which signals between electrodes can be detected
- Referential montage (ref.)
- Sequential montage (bw 2)
- Average reference montage
- Laplacian montage (average of surrounding electrodes subtracted)

Question 3

Alpha waves specs

Answer 3

• Rhythmic
• 8 - 13 Hz
• 20 - 200 μV (EEG)

Question 4

Alpha wave facts

Answer 4

• Mostly Occipital lobe
• Relaxed awake rhythm with eyes closed
• Upon mental activity, replaced by Beta
• Disappears during deep sleep

Question 5

Beta wave specs

Answer 5

• Irregular
• 14 - 30 Hz
• <25 μV (EEG)

Question 6

Beta wave facts

Answer 6

• Mostly Temporal & Frontal lobes
• Mental activity / excitement

Question 7

Gamma waves

Answer 7

• 30 - 300 Hz
• Short term memory matching

Question 8

Theta waves specs

Answer 8

• Rhythmic
• 4 - 7 Hz

Question 9

Theta waves facts

Answer 9

• Drowsy / Sleep (early phases)
• Disappointment & frustration in Adults
• In awake children, parietal & temporal regions

Question 10

Delta waves specs

Answer 10

• Slow
• 0.5 - 4 Hz

Question 11

Delta wave facts

Answer 11

• Normal deep sleep rhythm
• If present in awake = Tumor
• Voltage often 2-4 times larger
• Thalamic separation induces it

Question 12

EEG wave origin

Answer 12

• EPSP / IPSP generate field potentials which determine EEG waves
• APs do not contribute, too short & fast & asynchronous

Question 13

Magnoencephalography VS Electroencephalography

Answer 13

• EEG detects perpendicular dipoles from Gyri
• MEG detects horizontal dipoles from Sulci

Question 14

What is used for Magnoencephalography (MEG)

Answer 14

SQUID
Superconducting quantum interference device
- Very strong magnetometer to detect the low magnetic field

Question 15

Epilepsy classification

Answer 15

1) Partial
2) Generalized

Question 16

Partial epilepsy classification

Answer 16

Only part of the brain shows abnormal activity
- Partial simple seizures (conscious)
- Partial complex seizures (lost consciousness)

Question 17

Generalized epilepsy classification

Answer 17

Large regions of the brain involved, Consciousness is Lost
- Grand Mal: Tonic/Clonic m contraction on both sides of body
- Petit Mal: Brief loss of consciousness

Question 18

Partial simple seizure EXAMPLE

Answer 18

Jacksonian March
- Motor cortex origin
- Contralateral contractions
- Consciousness retained

Question 19

Partial complex seizure EXAMPLE

Answer 19

Psychomotor Epilepsy
- Limbic structures of Temporal
- Amnesia, abnormal rage, sudden anxiety or fear

Question 20

Petit mal seizure EXAMPLE

Answer 20

Absence Epilepsy
- 3 - 30 seconds of unconsciousness
- Twitching may occur (eyes)

Question 21

Epilepsy on EEG (Grand mal/Petit mal)

Answer 21

• Grand Mal: Big high frequency spikes
• Petit Mal: Spike-dome activity

Question 22

How much of lifetime is spent in sleep?

Answer 22

1/3

Question 23

How long is it possible to stay awake voluntarily?

Answer 23

3 days
4th day onwards major hallucinations

Question 24

Circadian rhythm

Answer 24

• ~ 25 hours
• Normally by light-dark cycle
• Melanopsin in retina detects light (484nm: blue)

Question 25

Circadian rhythm control

Answer 25

- Retino-hypothalamic tract - Suprachiasmatic Nucleus inhibits SYMP system during day - SYMP (NE) activates Pineal gland = melatonin

Question 26

Stage 1 sleep

Answer 26

Drowsy Alpha waves to Theta waves

Question 27

Stage 2 sleep

Answer 27

Slow Theta waves with small bursts of activity known as Sleep Spindles (12-14Hz) and K-complexes (large, slow potentials)

Question 28

Stage 3 sleep

Answer 28

Theta waves change to low amplitude Delta waves

Question 29

Stage 4 sleep

Answer 29

Delta waves (0.5-2Hz), deep sleep, autonomic ns drop BP & HR

Question 30

REM sleep

Answer 30

High frequency, low amplitude Only lasts few minutes

Question 31

Characteristics of REM sleep

Answer 31

- Desynchronized EEG - Muscle tone Lost - Thermoregulation lost - Dreams

Question 32

nREM sleep

Answer 32

Stages 1-4 Low frequency, high amplitude 1 to 1.5 hours

Question 33

Ascending Arousal System (AAS) Nuclei

Answer 33

- Tuberomamillary N - Locus Coeruleus - Laterodorsal Tegmental N - Pedunculopontine Tegmental N

Question 34

AAS role

Answer 34

- Ensures awake state - Tonic firing = awake - Lesion leads to coma

Question 35

Ventrolateral Preoptic Nucleus (VLPO)

Answer 35

- Lateral hypothalamic area - GABA & Galanin - Inhibit AAS - Active in sleep - Lesion leads to insomnia

Question 36

Orexin (Hypocretin) Neurons

Answer 36

- Lateral hypothalamic area - Orexin stabilizes AAS - Deficiency leads to Narcolepsy

Question 37

What determines sleep or arousal?

Answer 37

AAS / VLPO effect comparison

Question 38

Current Sink

Answer 38

Positive charge influx into cell causes E.C space to become a little more negative

Question 39

Current Source

Answer 39

Depolarization causes outward K+ so E.C space becomes more positive

Question 40

Positive vs Negative EEG wave

Answer 40

- Positive: Apical IPSP, Perisomatic EPSP - Negative: Apical EPSP, Perisomatic IPSP

Question 41

Learning

Answer 41

Change in reaction to stimuli based on experience

Question 42

Memory Types

Answer 42

- Implicit Memory - Explicit Memory

Question 43

Implicit Memory Overview

Answer 43

- Non-declarative - Not conscious - Automatic behaviors - Behavior, Motor, Secretory func.

Question 44

Explicit Memory Overview + types

Answer 44

- Declarative - Storage of past events - Semantic (world) & Episodic (yourself)

Question 45

Implicit memory Learning Types

Answer 45

- Associative learning - Non-Associative learning - Procedural learning - Priming

Question 46

Implicit Non-Associative Learning

Answer 46

- Habituation & Sensitization - Sensitization uses Serotonin on Gq/Gs

Question 47

Implicit Associative Learning

Answer 47

- Cerebellum & Amygdala involved - Conditioning a fear, emotional reactions - Operant conditioning (trial & error)

Question 48

Implicit Procedural learning

Answer 48

- Striatum involved - Activities learned by repeated practice

Question 49

Implicit Priming

Answer 49

- Neocortex involved - After a clue, retrieval of memory is improved

Question 50

Explicit Memory Mechanism

Answer 50

1) Encoding: attention, motivation, connecting prev. knowledge (prefrontal) 2) Consolidation: maintenance of info in CNS (synapses) 3) Storage: important in temporal lobe 4) Retrieval

Question 51

Engram

Answer 51

Unit of memories or trace in brain

Question 52

Hebb's Synapses

Answer 52

Basically same idea as LTP where efficiency of synapse is increased - AMPA inc, NMDA inc - Cam-II Kinase activation - AMPA activity increase