Lecture 6: Brain Arousal Systems Flashcards Preview

Year 1: 06. Neuro Exam 2 > Lecture 6: Brain Arousal Systems > Flashcards

Flashcards in Lecture 6: Brain Arousal Systems Deck (25)
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1
Q

What are the two parts of consciousness?

A

Arousal (being awake)

Awareness (conscious processing of inputs)

2
Q

What parts of of consciousness is missing in a coma?

A

Arousal and Awareness

EEG shows nothing

3
Q

What parts of of consciousness is missing in a persistent vegetative state?

A

Awareness (Arousal is present on EEG)

4
Q

What has to be damaged in cerebral cortex to cause comatose state?

A

Bilateral and massive damage

5
Q

Injuries to what areas often cause disruptions to consciousness?

A

Brainstem
Midbrain
Hypothalamus

6
Q

What is the status of cortical neurons in a persistent vegetative state?

A

Hyperpolarized (30 mv below threshold)

7
Q

What NTs take one from a coma to Arousal/Wakefulness?

A

Acetylcholine and EAA

8
Q

Where can Acetylcholine be found?

A
Pedunculopontine Tegmental (PPT)
Laterodorsal Nuclei (LDT)
9
Q

Where can EAA be found?

A

Reticular Activating System (RAS)

Parabrachial Nuclei

10
Q

Why is RAS not specific?

A

All sensory pathways converge at RAS and there is too much input - basically RAS is just an event detector

11
Q

Where do the dorsal pathways go?

A

Go to intralaminar nucleus of thalamus and then diffuse to rest of the brain

12
Q

Where do the ventral pathways go?

A

Skips thalamus via basal forebrain and hypothalamus and then diffuse to rest of the brain

13
Q

Between RAS and Parabrachial Nuclei, which one utilizes ventral pathway only?

A

Parabrachial Nuclei

14
Q

What happens if there is damage to PPT/LDT?

A

Severe Cognitive Defects

Slowing of Cortical processes

15
Q

What NTs take one from Arousal/Wakefulness to Awareness?

A

Norepinephrine

Serotonin

16
Q

What is the role of norepinephrine?

A

Startle and Alert (EEG Manifestation)

17
Q

What is the role of serotonin?

A

Quiet Awareness

18
Q

For arousal, what pathways are used?

A

Both dorsal and ventral

19
Q

What NT takes one from Awareness to Alertness?

A

Dopamine

20
Q

Where is dopamine found?

A

Ventral Tegmental Area

Substantia Nigra

21
Q

What does dopamine do?

A

Cognitive Function
Motor Function
Emotion (pleasure)

22
Q

How are oscillations created on EEG?

A

Dopamine + EAA release GABA???

23
Q

What is affected in patients with Alzheimer’s?

A

Cholinergic systems: slow mental processes and impaired memory formation

24
Q

What can treat some people in a persistent vegetative state

A

Levodopa

25
Q

What causes spindle-like discharges during sleep?

A

Thalamocortical neurons are hyperpolarized and show occasional bursts