Consciousness – Lecture Notes
Jaimy van Trigt – 13752278
Contents
Lecture 1: Consciousness: From Theory to the Clinic ............................................................................. 2
Lecture 2: Illusions and Lesions............................................................................................................... 9
Lecture 3: Manipulations of Consciousness.......................................................................................... 23
Lecture 4: Consciousness Enter the Lab................................................................................................ 30
Lecture 5: Unconscious Processes and the Function of Consciousness ............................................... 40
Lecture 6: Meditation as a Tool in the Scientific Study of Consciousness and Neurocognitive Plasticity
.............................................................................................................................................................. 51
The Role of Attention in Consciousness and Signature of Consciousness ........................................ 62
,Lecture 1: Consciousness: From Theory to the Clinic
Introduction to this Course and the Topic of Consciousness
What we will do today:
• Introduction to the structure of this course
• Introduction to the challenges of consciousness research
• Some philosophical background
Topics that will be covered
1. Course overview and specifics.
2. What is consciousness?
3. Can we measure it in the brain?
4. What is consciousness for?
5. Mechanistic theories of consciousness?
6. What happens when we lose consciousness (e.g. Coma, vegetative state)?
What is the switch from going from an unconscious to a conscious state?
6. Who have consciousness (monkeys, babies, computers, etc.)?
Course Overview
• 13 lectures
• 2 guest lectures (recorded)
• Lectures roughly follow the chapters of Dehaene (2014) with additional scientific articles
• Additional course content is provided in the lectures
• For other details see syllabus on Canvas: also for when to read which chapters/article
• Recorded lectures (corona times) are posed on Canvas every week
o Important note: The lectures/pdf's with the current course details/content etc. Are always
leading.
• If you have questions: first check the syllabus (if not in there, I prefer to answer if
before/after class instead of via e-mail)
2 guest lectures (which are recorded)
• 2 speakers
• Each of them addresses a topic of consciousness of special interest:
Prof. Dr. Heleen Slagter Attention and meditation (EEG)
Dr. Anouk van loon Ketamine and consciousness (fMRI)
The book
Stanislas Dehaene (author of the book) follows global workspace theory of consciousness.
Probably the most accepted view.
This book is not written to be used as a textbook. Meaning it can be difficult to find the relevant
parts of the book for this course.
,Scientific Articles
• 9 original research articles
• Posted on Canvas
• See syllabus for planning, when to read etc.
9 scientific articles to read for this course (planning is on syllabus)
Why Scientific Articles?
• Primary research articles are the basis of the content of textbooks.
• It is important to evaluate the validity of the conclusions and knowledge that ends up in out
textbooks.
• Primary research articles illuminate aspects of scientific enquiry that textbooks ignore, e.g.,
the research question is highlighted, the authors' hypotheses are spelled out specifically, the
experimental design is explained in detail, and the results are complete
• Research articles illustrate the "spiral" nature of scientific research, e.g., alterative
explanations for the data are discussed and ideas for further research are often mentioned
that could help distinguish among competing theories and claims.
• Primary research articles, when chosen carefully, add to the understanding of the subject
matter and objectives of the course ("better learning").
• Reading and analysing scientific literature improves critical thinking abilities and knowledge
of scientific facts.
• It simulates interest in scientific research.
Reasons as to why reading scientific articles is important
It's important to be able to make your own conclusion based on the scientific articles instead of just
reading about other people's interpretations that are presented in books.
What you should know after reading an article (for the exam):
• The question addressed by the research.
• The population and equipment used in the study.
• An overall picture of the (experimental) protocol used (e.g., what data was collected, e.g.,
neuroimaging method, behavioural task, etc.).
• The methods used for data analysis (univariate contrast, multivariate decoding, etc.).
• The main results (all experimental factors and dependent measures are important).
• The conclusions that can be drawn from the article.
• Limitations of the study (what could have been done better?)
• Why the study is relevant for the field of consciousness in general.
• Not all the statistical details!
Two exams
Partial exam (introduction and 1-3 of book, 1-6 lectures)
Only multiple choice questions.
The exam will be in a different building than stated now, data and time remains the same.
,Final exam (4-7 of book, 7-13 of lectures)
Multiple choice and open questions
• A passing grade (5.5 or higher) must be obtained, based on the weighted average of the
grades of both exams.
• The retake in January is one exam covering all course material, so the entire book, all articles
and lecture material.
• Exam questions are based on the book material, provided articles, lectures and provided
links/YouTube videos in the lectures.
• No course material can be used while taking the exam.
• Exams are in TestVision and on campus
1. What is Consciousness?
• I am not going to give you the answer (which is actually impossible, there is so much
disagreement)
• In this course: No golden truths, but a lot of data/theories/ideas/discussion
• Learn to appreciate the accumulating knowledge about a scientific topic.
There is not a single agreed upon definition of consciousness
Perspective of this course
• Cognitive Neuroscience approach
• Combination of Psychology and Neuroscience (the biology of mind)
• I will introduce some philosophers, but mainly to appreciate the difficulty of the questions
we are trying to tackle.
What is it like to be
A bat...
A coffee cup...
There's a pretty strong consensus that a coffee mug is not conscious, since it's not alive.
But then, there is a debate about whether AI is conscious, even though AI also isn't alive.
"If there is something it is like to be an animal, i.e., a bat (or a computer or a baby) then that "thing"
is conscious. Otherwise it is not."
This "likeness" becomes very important when you look at a more clinical picture.
For example, what is it like to be in a coma?
Is it nothingness, or is it like something to be in a coma.
Or what is it like to be a baby? You can't really ask and you also cannot remember what it was like
when you were a baby. Same goes for animals.
,A Difficult Problem
• Consciousness questions have confused philosophers and scientists for millennia.
• For long the question of consciousness lay outside the boundaries of normal science.
• Fuzzy, ill-defined domain whose subjectivity put it forever beyond the reach of objective
experimentation.
• No serious researcher would touch the problem: Speculating about consciousness was a
tolerated hobby for the aging scientist (with tenure, see TED talk Daniel Dennett).
For a long time, scientists didn't study consciousness.
Around 1995, some scientists did start to wonder about consciousness. Mostly older scientists did
this however, when they're already nearing the end of their career.
Because the definition is so ill-defined, it's too risky for young scientists or PhD candidates to focus
on this topic.
An official ban: a few quotes from the book
Then here we are...
• Can modern cognitive neuroscience turn this age-old philosophical problem into an
experimental question?
• Is the human mind smart enough to understand its own subjectivity? (This is a serious question,
e.g., philosophers such as Colin McGinn)
o "We will never find out what consciousness is"
o Finding out "the basis of consciousness in the physical world (i.e., material world,
the brain) exceeds our cognitive limits"
Philosophers talking...
Prof. David Chalmers (NYU):
• 1996, The Conscious Mind: In Search of a Fundamental Theory,
• 1999, Toward a Science of Consciousness III: The Third Tucson Discussions and Debates
Why is consciousness so mysterious?
Descartes: we can doubt anything, except the fact that I am conscious right now. ("I think
therefore I am").
Is consciousness the first element or a derivative of something biological like the brain?
, Philosophical zombies
Somebody who you can't tell isn't conscious but doesn't actually have any free will
of consciousness.
This could actually be imaginable. You can never be 100% sure of the
consciousness of somebody else. Meaning that there could be a possibility that just
the physical biological building blocks wouldn't necessarily be enough for
consciousness to exist.
Consciousness could have emerges randomly, and developed further since it helped us
survive. But you can actually explain any kind of survival behaviour with just mechanisms that
are happening in the brain, which could happen without consciousness.
Qualia: The raw sensation of experience (subjectivity of experience). All experiences fell a
certain way to people.
The colour scientists thought experiment.
David Chalmers
• "There is more to consciousness than a physical process in the brain"
• "I don't think that the hard problem of consciousness can be solved purely by Neuroscience"
The brain as a radio that plays consciousness. The brain is then essentially a radio. This is one of the
theories about consciousness in relation to the brain.
But then how to you explain the loss of consciousness because of brain damage? (Radio's broken, no
more signal, etc.)
Chalmers "Easy" Problems
Easy problems: Are about abilities and functions we need only mechanisms to explain those. These
are problem that we have not solved (perception, memory, etc.) but in principle we know how to
solve (even if we have not done yet)
Examples:
• The ability to discriminate, categorize, react to environmental stimuli
• The integration of information by a cognitive system
• The reportability of mental states
• The focus of attention
• The deliberate control of behaviour
• The difference between wakefulness and sleep
,Easy = Still very difficult (maybe requiring decades of science) but we can sort of see the solution
lying ahead
Chalmers "Hard" Problem
The hard problem: Why and how do subjective experiences arise from objective brains (neural
processes)? "Explaining the function doesn't explain the experience".
• Why aren't the 'easy' processes carried out 'in the dark', why do we have experiences
associated with them?
• The way things look, feel, sound, etc.
• "What is it like" (to be a bat, to feel sad, etc)
• Phenomenal experiences, P-consciousness
• The private and intrinsic phenomena of consciousness. For example 'yellow' or 'pain':
QUALIA (quality of experience)
Sophisticated actions/decisions in unconscious machines ("in the dark")
All these functions are probably done without consciousness.
So why aren't we just like all these things, but much more complicated, and don't need
consciousness.
Philosophers talking
Prof. Daniel Dennett
Consciousness Explained (1991)
Darwin's Dangerous Idea (1995)
Consciousness is not a separate function, it's the accumulation of all the function. If you explain all
the other functions in the brain, you will have explained consciousness.
"Getting rid of the homunculus"
There is no little picture in the head, there is no little guy in the head that looks at the picture.
Just because there is no homunculus doesn't mean that you don't exist. It just means that you're
body is simply all that you are made off.
A mindless, mechanical process which created/generates minds.
Turing saw how you could eliminate the "smart mind" and create a machine which could take over
simple human tasks like computation.
Algorithm: procedure that requires no intelligence.
Daniel Dennett
• "The factory is empty"
o There is no big boss in there at all
• The mind is a mechanism (of interacting neurons)
• What isn't there, doesn't have to be explained (the hard problem is an illusion)
"The hard problem arises from the false intuition that we have explained perception, memory,
attention, language, and all the other details, there would still be something left out -
"Consciousness itself"."
,A Quick Recap
• Dualistic ideas about consciousness: the mind and body are not identical and consciousness
cannot be reduced to pure brain activity (video David Chalmers, see also descriptions of the
ideas by Descartes in the book)
• Materialism: All emergent phenomena, including consciousness, are the result of material
properties and interactions in the brain (video Dennett until 11.40)
• Dehaene, author of the book, and most cognitive neuroscientists are materialist (but you
will see that the hard problem comes up all the time when talking about consciousness)
What is consciousness?
• Dehaene: A conscious experience is a percept, thought, action or feeling that can be
(re)produced or reported about (later more discussion about this).
• Lamme (author of one of the articles): Consciousness is subjective experience of
phenomenal experience. The way things seem to me, as opposed to how they are
objectively.
• Subjective experience of something
• Qualia: Individual instances of subjective conscious experience (i.e., pain of a headache, the
taste of wine, or the perceived redness of an evening sky). The 'what it is likeness' of mental
states or systems/beings.
• Later more on conscious states/levels (Coma, etc.)
Summary
• Introduction to this course and the topic
• Introduction to the (philosophical) challenges of consciousness research
• Some philosophical background and definitions
,Lecture 2: Illusions and Lesions
Can Consciousness be Reduced to Brain Activity?
Overview
• Illusions and their relevance
• Brain damage and the loss of visual awareness
• Dissociations between perception and action
Your consciousness perception is a construction of the senses
Not an exact replica of the outside world.
What do illusions tell us about neuroscience? How does knowledge of these illusions help the
science of neuroscience.
The most important take home messages from the illusions is that:
Your conscious perception is a construction of the senses.
Not an exact replica of the outside world
1/3 of the time you are blind
Due to the amount of saccades you make. But the world isn't perceived as a series of rapid pictures
picked up by these saccades.
The same goes for head movements. You don't see the whole world around you moving all the time.
Your brain fills in the blanks, to make a coherent. Fluent picture.
If you focus on the cross in the middle, then the purple dots will start to disappear, while the picture
itself doesn't change at all.
, Conscious perception is serial: You can only perceive one interpretation at a time.
Which is why you cannot see both sides as facing forward, you can only see one side as being in
front at a time.
Also, the dress, aka "dressgate"
What colour is this dress?
The difference lies in whether you see the dress as being in the shadow or as being in sunlight.
Note that expectations, context, and learning play a large role in our consciousness perceptions