consciousness

Question 1

blindsight

Answer 1

Associated with having some damage in the occipital lobe (V1)
Lesion in occipital lobe – primary visual cortex - V1
V1 = critical first stage where the visual signals arrive

Question 2

cortical blindness

Answer 2

damage V1, you block off further access to the ventral stream and the dorsal stream
No further visual processing was going to happen
Usually doesn’t affect the whole visual field

Question 3

Patients: DB & GY

Answer 3

Although these individuals say they can’t see, but if you force them to choose between something, they can discriminate the two options relatively well (80% accuracy)

Forced choice responding

Question 4

beta pattern (EEG)

Answer 4

13 - 24 frequency

Normal waking, alert problem solving

Question 5

alpha pattern

Answer 5

8 - 12

Drowsy, deep relaxation, meditation

Question 6

theta

Answer 6

4 - 7

Light sleep

Question 7

delta

Answer 7

Less than 4

Deep sleep

Question 8

stage 1 sleep

Answer 8

Lasts about 5 minutes – aka hypnagogic sleep

Breathing is deeper & more regular

Presence of theta waves

Easy to awaken

Question 9

stage 2 sleep

Answer 9

Lasts about 20 min

Presence of sleep spindles in EEG recording
Sleep spindle = Spikes of EEG activity and a burst
Distinguishes from Stage 1

Relatively easy to awaken (but more deeply asleep than Stage 1)

Question 10

stage 3 & 4 sleep

Answer 10

Also known as slow wave sleep
Much slower waves + higher amplitude

Slow, high amplitude waves in EEG recording – delta waves

Difficult to awaken – deeply asleep → feel disoriented when woken up

Heart rate & breathing slow down; body temperature decreases

Question 11

how to tell the difference from stage 3 and stage 4 sleep

Answer 11

How many of the delta waves there are

More than 50% = stage 4

Question 12

REM sleep stage

Answer 12

Rapid eye movements

Harder to awaken than in any other stage of sleep

EEG record resembles waking pattern (paradoxical sleep)

Postural muscles are relaxed

Breathing & heart rate fast & irregular; genital arousal

Question 13

dreaming in REM sleep compared to other sleep stages

Answer 13

Commonly associated with the dreaming state of sleep (narrative type dreams)
If dreaming in other stages → more like thinking about something (not as dramatic)

Question 14

coma

Answer 14

Absence of wakefulness. Closed eyes no response to stimulation

Question 15

vegetative state

Answer 15

Wakefulness with reflexive behaviour

Question 16

Minimally conscious state

Answer 16

Wakefulness with non-reflexive behaviour / some evidence of command following

Question 17

locked-in syndrome

Answer 17

awake and conscious but unable to make responses (complete paralysis)
ex:
- coma
- vegetative state
- minimally conscious state

Question 18

value of neuroimaging methods for DoC

Answer 18

Aims: communication & therapeutic improvement
Using those kinds of methods ^ to open up a new way of communication with a patient who is not able to respond
Detect which level of consciousness they are in, see if they can recover, if they’re able to go back to normal