Consciousness and Brain Activity Flashcards Preview

Medicine, Year 1 Block 6 (Psychological Medicine) > Consciousness and Brain Activity > Flashcards

Flashcards in Consciousness and Brain Activity Deck (25)
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1
Q

What is the medical definition of consciousness?

A

State of awareness and responsiveness to one’s surroundings

2
Q

What is the “lowest” level of consciousness?

A

Brain death

3
Q

Describe Locked in Syndrome

A

Patient has awareness, sleep-wake cycles, meaningful behaviour but is isolated due to facial / muscle paralysis

4
Q

Describe a state of normal loss of consciousness

A

Sleeping

5
Q

Describe three states of abnormal loss of consciousness

A

Coma
Anaesthesia
Vegetative State

6
Q

What is the most common cause of serious loss of consciousness worldwide?

A

Cerebral malaria

7
Q

Aside from Cerebral Malaria, give 4 other causes of losing consciousness

A
Stroke
Cardiovascular
Diabetes
Drug-induced
Epilepsy
Head Injury
Dementia
8
Q

What is AVPU?

A

A way of assessing patient’s responsiveness

A: Patient is awake
V: Patient responds to voice
P: Patient responds to pain
U: Patient unresponsivess

9
Q

A fully conscious patient has a GCS of..?

A

15 (maximum)

10
Q

A person in a deep coma has a GCS of..?

A

3 (minimum)

11
Q

What are the three variables measured for the Glasgow Coma Scale?

A

Best Eye Response (E)
Best Verbal Response (V)
Best Motor Response (M)

12
Q

To be in a coma, patient would have a GCS of..?

A

8 or less

13
Q

A GCS of 9 - 11 is..?

A

Moderately severe injury

14
Q

A GCS greater than or equal to 12 is..?

A

Minor injury

15
Q

What is the criteria for brain stem death?

A

Irreversible loss of capacity for consciousness, to breathe, and loss of brain-stem function

16
Q

Give examples of 5 brainstem reflexes

A
  • Pupil response
  • Corneal reflex
  • Vestibular-ocular reflex (VOR)
  • Cough / gag reflex
  • Respiratory effort
17
Q

What is the main system in the brain which regulates consciousness?

A

Reticular Activating System

18
Q

What is the Reticular Formation?

A

A collection of nuclei belonging to the Reticular Activating System, found in the mid-brain. Diffuse, no clear boundaries

19
Q

What are the four principle sets of nuclei in the Reticular Activating System?

A

Locus Coeruleus
Raphe Nuclei
Ventral Tegmental Area
Cholinergic Nuclei

20
Q

What are the Neurotransmitters used in each of the Nuclei of the RAS?

A

Locus Coeruleus: NA
Raphe Nuclei: 5-HT
Ventral Tegmental Area: DA
Cholinergic Nuclei: ACh

21
Q

What are the two main types of sleep?

A

Synchronised / NREM / Non-REM

Desynchronised / REM

22
Q

The sleep-wake cycle is controlled by what fibres in the RAS?

A

Cholinergic Nuclei

23
Q

Oscillations in the EEG are generated by interactions between which 3 neurones?

A
  • Thalamocortical
  • Reticular
  • Corticothalamic
24
Q

During wakefulness, what sort of oscillatory waves are there?

A

Alpha and beta waves

25
Q

How long is the body clock’s day?

A

24.5 - 25.5 hrs