9 - Reticular formation Flashcards Preview

Semester 5 - Neuro > 9 - Reticular formation > Flashcards

Flashcards in 9 - Reticular formation Deck (30)
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1
Q

Define arousal:

A

Emotional state associated with some kind of goal or avoidance of something noxious

2
Q

Define consciousness:

A

An awareness of both the external and internal world states, requiring 1) cerebral cortex and 2) reticular formation

3
Q

Where is the reticular formation located?

A

Brainstem

4
Q

Which neurotransmitters are important in the reticular formation and its connections with the cerebral cortex?

A
  • MAINLY Ach
  • Histamine
  • Glutamate
5
Q

The reticular formation achieves input from where?

A
  • Cerebral cortex

- Somatosensory system

6
Q

The reticular system connects with the cortex via which 3 structures in the brain?

A

1) Basal forebrain nuclei
2) Hypothalamus
3) Thalamus

7
Q

What are the 3 factors which contribute to a GCS score?

A

1) Best motor response
2) Best verbal response
3) Eye opening

8
Q

What is the scoring system for the best motor response in a GCS score?

A
6 = obeys command
5 = localise to pain
4 = withdraws from pain
3 = flexes to pain
2 = extends to pain
1 = no response
9
Q

What is the scoring system for the best verbal response in a GCS score?

A
5 = orientated
4 = confused conversation
3 = inappropriate words
2 = incomprehensible sound
1 = no response
10
Q

What is the scoring system for eye opening in a GCS score?

A
4 = spontaneous 
3 = responds to speech
2 = responds to pain
1 = no response
11
Q

How can you assess consciousness?

A
  • GCS

- EEG

12
Q

What is an EEG and what does it do?

A

Encephalalogram

- Measures the combined activity of thousands of neurones in a given part of the cortex

13
Q

What are the 3 possible mechanisms resulting in a disorder of consciousness?

A

1) Diffuse cortical dysfunction (ie metabolic disturbance)
2) Pressure inhibiting the reticular activating system (ie RICP)
3) Direct lesion to the reticular activating system (ie brainstem infection)

14
Q

Which disorder of consciousness results in a flat EEG?

A

Brain death

15
Q

What is the GCS score of someone in a coma?

A

GCS < 8

16
Q

In which disorder of consciousness is there no detectable sleep-wake cycle?

A

Coma

17
Q

What are some common causes of a coma?

A
  • Drug poisoning
  • Hypoxia
  • Stroke
18
Q

What is are the main differences between coma and persistent vegetative state?

A
Persistent vegetative state:
- spontaneous eye opening
- can localise to pain via brainstem reflexes
- Detectable sleep-wake cycle
All of which do not occur in a coma
19
Q

Which of a coma and persistent vegetate state is damage to the cortical cells only?

A

Persistent vegetative state

- Coma is also damage to brainstem

20
Q

What is the name given to the disorder of consciousness resulting from a brainstem stroke?

A

Locked-in syndrome

21
Q

Where is the damage in Locked-in syndrome, and how does it present?

A

Corticospinal tracts damaged at the Pons

  • All somatic motor functions lost
  • Eye movements preserved
  • Consciousness and sensation fully intact
22
Q

Occlusion of which arteries results in a brainstem stroke?

A

Basilar and Pontine arteries

23
Q

What are the 3 types of delirium?

A
  • Hypoactive
  • Hyperactive
  • Mixed
24
Q

Describe someone with hypoactive delirium:

A

Sleepy, apathetic, lethargic, decreased motor activity

25
Q

Describe someone with hyperactive delirium:

A

Agitated, aggressive, irritable, restless

- May have hallucinations/delusions

26
Q

What are the most common type of hallucinations experienced by people with hyperactive delirium?

A

Visual hallucinations

27
Q

What are the risk factors of delirium?

A
  • Old age > 65yrs
  • Multiple co-morbidities
  • Dementia
  • Physically fragile
  • Renal impairment
  • Previous delirium
28
Q

Name some types of drugs which can precipitate delirium:

A
  • Benzodiazepines
  • Opioids
  • Anticholinergics
  • Anti-parkinsonian medications
  • Steroids
  • Anaesthesia
29
Q

Name some COMMON causes of delirium in the elderly:

A
  • Pneumonia
  • UTI
  • Sensory deprivation (no glasses/hearing aid)
  • Faecal impaction
  • Urinary retention
  • Renal failure

This is only a few!!

30
Q

In which disorder of consciousness is there a reversal of the sleep-wake cycle?

A

Delirium