Lecture 1: Consciousness
● Everybody knows what consciousness is
○ However, it is difficult to study consciousness in a scientific way
Levels of consciousness
● Let's start with an extreme position:
○ What is it like to be unconscious?
■ Unconscious is something else than dead, because being dead means no
consciousness at all
A definition by Armstrong 1981 on unconsciousness
● “A totally unconscious person does not perceive, has no sensations, feelings or pangs of
desire. He cannot think, contemplate or engage in any sort of deliberation”
What is the next step?
● Can you be conscious just a little?
○ According to Armstrong, yes! And he refers to this as ‘ minimal consciousness’
Minimal consciousness (Armstrong 1980)
● “A low level of awareness that occurs when the mid inputs sensations and may output
behavior”
● This sounds vague but it becomes clearer when looked at examples for when this can
occur
○ Examples:
■ 1. You turn over during sleep when poked
■ 2. You scratch an itching leg without noticing
■ 3. You change position whilst studying
● Armstrong was a philosopher and whilst philosophers can do great things for psychology,
actual psychologists might look different at these examples
Levels of consciousness
● Psychologists would argue that such behaviors are caused by unconscious processes
● When introducing ‘unconscious processes’ we do NOT refer to ‘the unconscious’ as
postulated by Freud
○ According to Freud: there is a part of your personality from which violent and
sexual urges motivate someone into action
■ But there is no empirical evidence for this postulation at all!
○ There is evidence for unconscious processes but no evidence for unconscious
personality
○ Although, this is still very intriguing and inspiring!
1
,● It is ‘unconscious’ in the sense that people are unaware of certain things:
○ 1. You are unaware of the reasons for the behavior (the poke, the slight itch, the
decreased blood flow in the leg)
○ 2. You are unaware of the brain processes that lead to the behavior
○ 3. You are unaware of the behavior itself
● Since unconsciousness is described in terms of being unaware, awareness seems to be
important
○ What is important is the awareness of:
■ Thoughts, ideas and feelings
■ Your surroundings
■ Yourself
● This shows that consciousness is about something
● You are conscious about something!
● In the book this is called ‘the intentionality of consciousness’
● When awake and with open eyes it seems that we are aware of everything
○ But how do we do that?
■ We use our senses (this is well studied in psychology because without
your senses it would be impossible to react to anything to happens in your
environment)
● For example vision (vision is the MOST studied)
● We know a lot about the processes that the brain performs when
the brain processes visual imagery it receives from the eyes
2
, Vision and the brain
● The visual cortex is on the back of everyone's brain
● As long as you have your eyes open, you will have a lot of neurons and activity in the
visual cortex
● This is also probably the most active brain part at the moment of studying now
● The left visual field is transported to the right of your visual cortex
● The right visual field is transported to the left of your visual cortex
● From the right of your visual cortex you process information from your left visual field
● From the left of your visual cortex you process information from your right visual field
● Then from the visual cortex, information is processed up and down
● There are estimates that 25 to 40 percent of your brain is just processing visual
information
● Information from the visual cortex travels on to other parts of the brain
● Both eyes receive information from both visual fields
Patients
● We know that after brain damage, some people are not visually aware of (part of) their
surroundings anymore
○ So they cannot be aware of some parts of their surroundings anymore
■ It is important to realize that these people (before the brain damage) were
completely normal
3
● Everybody knows what consciousness is
○ However, it is difficult to study consciousness in a scientific way
Levels of consciousness
● Let's start with an extreme position:
○ What is it like to be unconscious?
■ Unconscious is something else than dead, because being dead means no
consciousness at all
A definition by Armstrong 1981 on unconsciousness
● “A totally unconscious person does not perceive, has no sensations, feelings or pangs of
desire. He cannot think, contemplate or engage in any sort of deliberation”
What is the next step?
● Can you be conscious just a little?
○ According to Armstrong, yes! And he refers to this as ‘ minimal consciousness’
Minimal consciousness (Armstrong 1980)
● “A low level of awareness that occurs when the mid inputs sensations and may output
behavior”
● This sounds vague but it becomes clearer when looked at examples for when this can
occur
○ Examples:
■ 1. You turn over during sleep when poked
■ 2. You scratch an itching leg without noticing
■ 3. You change position whilst studying
● Armstrong was a philosopher and whilst philosophers can do great things for psychology,
actual psychologists might look different at these examples
Levels of consciousness
● Psychologists would argue that such behaviors are caused by unconscious processes
● When introducing ‘unconscious processes’ we do NOT refer to ‘the unconscious’ as
postulated by Freud
○ According to Freud: there is a part of your personality from which violent and
sexual urges motivate someone into action
■ But there is no empirical evidence for this postulation at all!
○ There is evidence for unconscious processes but no evidence for unconscious
personality
○ Although, this is still very intriguing and inspiring!
1
,● It is ‘unconscious’ in the sense that people are unaware of certain things:
○ 1. You are unaware of the reasons for the behavior (the poke, the slight itch, the
decreased blood flow in the leg)
○ 2. You are unaware of the brain processes that lead to the behavior
○ 3. You are unaware of the behavior itself
● Since unconsciousness is described in terms of being unaware, awareness seems to be
important
○ What is important is the awareness of:
■ Thoughts, ideas and feelings
■ Your surroundings
■ Yourself
● This shows that consciousness is about something
● You are conscious about something!
● In the book this is called ‘the intentionality of consciousness’
● When awake and with open eyes it seems that we are aware of everything
○ But how do we do that?
■ We use our senses (this is well studied in psychology because without
your senses it would be impossible to react to anything to happens in your
environment)
● For example vision (vision is the MOST studied)
● We know a lot about the processes that the brain performs when
the brain processes visual imagery it receives from the eyes
2
, Vision and the brain
● The visual cortex is on the back of everyone's brain
● As long as you have your eyes open, you will have a lot of neurons and activity in the
visual cortex
● This is also probably the most active brain part at the moment of studying now
● The left visual field is transported to the right of your visual cortex
● The right visual field is transported to the left of your visual cortex
● From the right of your visual cortex you process information from your left visual field
● From the left of your visual cortex you process information from your right visual field
● Then from the visual cortex, information is processed up and down
● There are estimates that 25 to 40 percent of your brain is just processing visual
information
● Information from the visual cortex travels on to other parts of the brain
● Both eyes receive information from both visual fields
Patients
● We know that after brain damage, some people are not visually aware of (part of) their
surroundings anymore
○ So they cannot be aware of some parts of their surroundings anymore
■ It is important to realize that these people (before the brain damage) were
completely normal
3
