Intro to consciousness

Question 1

Where has research on consciousess focused in the past decades and what problem is associated with this?

Answer 1

There has been much progress on “easy” problems of consciousness – memory, attention, decision-making, sensory discrimination (etc.) But: we refrain from asking deeper questions, e.g. how is phenomenal content associated with neural activity (”hard” problem; Chalmers)

Question 2

What is meant by phenomenal content?

Answer 2

Having qualitatively rich experiences (What is it like to be a bat? An orca? Octopus?)

Question 3

Exemplify the hard problem in regards to a painting

Answer 3

correlate pictorial elements (shape, color, etc.) with neural activity in different brain areas; but what is their exact relationship? “Neural correlate of consciousness” (How is our appreciation of its rich qualities associated with simple neural correlates in the brain.) There is also differences in the physical description of light in terms of its waves and how we actually experience colour.

Question 4

What are some things consciousness is often conflated with but is distinct from?

Answer 4

Consciousness vs. Self-consciousness (consciousness ~ awareness). Consciousness is different from responsibility, volition, deliberation

Question 5

Evaluate the stance of eliminative materialism in terms of consciousness

Answer 5

Can everything about the “mind” be phrased/ explained in terms of neurons? If so, we can abolish “folk psychology”: set of assumptions and ‘mental’ concepts we use in daily life to describe behaviour and experiences of ourselves and others. Eliminative materialism tries to get rid of all these ‘mental’ terms. Through this, however you may get rid of some important aspects such as the perception of colour. However can we say that a colour experience is an experience of a particular electromagnetic wavelength?

Question 6

Do the following terms refer to consciousness?

Perception
Sensing
Sensation
Detecting

Answer 6

*“Sensing”: ambiguous term (e.g. “smoke sensor”) in terms of (non-) consciousness
*“Detecting”: mere signalling of a specific event (can be conscious or non-conscious)
*Perception/sensation: refers to conscious experience (or just: “experience”)

Question 7

What is self consciousness and how is it not the same as consciousness?

Answer 7

It is the concept of I, however consciousness can happen independent of this.

Question 8

What is meant by intentionality in the brain?

Answer 8

Neurons somehow represent things that have meaning; they represent things that are not themselves. e.g. imagine fireworks – somehow neurons are able to
represent exploding colorful sparks without exploding themselves! (lesion neurons => lose experience)

Brain generates something having intentionality – “aboutness”, e.g. we think about vegetables without having them in our brains

Question 9

How is there dual use of the term meaning in

Answer 9

Associative meaning: set of learned connotations associated with a percept
Phenomenal meaning: percept stripped of those associations (“memoryless”)

Question 10

What does the term phenomena mean?

Answer 10

Subjectively experienced

Question 11

Give two ‘ideas’ of what representations are

Answer 11

*Idea #1 (broad): any sort of depiction / rendition / model
*Passive carrier: has no idea what the depiction means (e.g. flatscreen)

*Idea #2 (narrow): information package conveyed by brain activity (active in the sense: it has meaning to the carrier)

We are more concerned with 2 obviously

Question 12

Give three examples of maps as brain representations

Answer 12

*Example: retinotopic map in visual cortex (e.g. V1)
*Tonotopic map in auditory cortex (A1; frequencies)
*Somatotopic map in somatosensory cortex (e.g. S1)

Question 13

How well are maps associated with consciousness?

Answer 13

Maps also widely found in subcortical regions,
not particularly associated with consciousness

Question 14

How is there a disparity between the types of maps and our perception?

Answer 14

Diversity of maps: e.g. retinotopic, craniotopic, allocentric: but we seem to have one common viewpoint (=visual perspective)

Question 15

What problem arises with this disparity of brain maps and perception?

Answer 15

Notion of brain map: unclear how meaning arises
Who or what reads our brain maps?; Is there a homunculus reading our brain maps?

Question 16

What makes the visual cortex “visual”?

Answer 16

Classically: the fact that it receives inputs (electrical impulses) indirectly from the eyes

Question 17

What is an alternative hypothesis to this classic interpretation of the visual cortex?

Answer 17

Labelled lines hypothesis: sensory modality is determined by peripheral receptor and afferent nerve (e.g. retina & optic nerve)

Question 18

What are two problems with this labelled lines hypothesis?

Answer 18

Problem 1: a cortical neuron has no knowledge
where its inputs are coming from
(action potentials arriving are not “labelled”)

Problem 2: just having sensory or feature detectors is not enough for perception (a smoke detector is also not considered to “smell” the smoke; it just transmits numbers)

How does the rest of the brain “know” what it means if a feature detecting neuron is firing

Question 19

What does it mean to say that cortical areas are not intrinsically “visual” or “auditory” ?

Answer 19

Neocortex is ~‘equipotential’: if retinal input is rerouted to the auditory cortex, then ‘auditory’ cortex develops a map of visual space (retinal), not a tonotopic (cochlear) map.

Question 20

Describe a study that demonstrates how the neocortex is equipotential

Answer 20

• Ablation (burning/ freezing to cause scarring )of the superior colliculus carried out
• Removal of inferior colliculus fibers innervating the MGN is also carried out

This resulted in the optic fibers connecting to MGN (medial geniculate nucleus; auditory thalamus) and hence photic inputs reach ‘auditory’ cortex.

Result: The ‘auditory’ cortex develops a visual map, not a tonotopic (cochlear) map

Question 21

What conclusion can we draw about the auditory cortex from this study on the retinotonic map in the MGN?

Answer 21

Formation of a tonotopic map (for sound) is not an intrinsic property of the (auditory) cortex, but is imposed on it during development

Question 22

How was this research on rewiring in AC further developped in a future study?

Answer 22

Visual orientation tuning was achieved in the ferret AC through similar rewiring measures; rewired auditory cortex behaves much like a normal primary visual cortex
Concl: cortical areas are not “predestined” to process a modality

Question 23

What can we concluse about encoding as a whole from this work?

Answer 23

*Auditory cortex is not intrinsically “auditory”
*Peripheral input is important for how a cortical area processes inputs (cortex has
developmental equipotentiality)
*This likely relates to the input statistics, needed to generate specific feature detectors

Question 24

Therefore, are feature detectors enough? Give an example

Answer 24

No: Example: map of simple luminance-sensitive neurons depicting a face in pixels (see docs). How does a neutral observer (unaware of retinal origin) figure out that this represents the visual image of a face?
=> Activated neurons may as well be part of a tonotopic or somatosensory map

N.b., an external observer knows about positioning of neurons relative to each other – unlike a brain system processing the maps ́s output

=>A priori: input statistics could apply to any modality
=>Just having these statistics is not enough to infer the modality

Question 25

Look at the diagram of the snake and the brain in docs, what is wrong with this diagram?

Answer 25

The snake image is suggested to travel through the brain, but inside the brain, we find neurons & spike patterns, not images of snakes. The image could be meant symbolically, as a generic representation of a snake, but then: where is the snake as we see it? If it’s not in the brain, where else?

Question 26

Chapter three is called ‘peeling off our conscious lives’, what question does this refer to?

Answer 26

Which processes can you “peel off” until you finally lose consciousness? Which processes are key?

Question 27

Which aspects of cognition: are key to consciousness? What 6 candidates are presented in the slides ?

Answer 27

• Perception in individual sensory modalities:
  – vision, hearing, touch, olfaction, taste, pain, thermoception, vestibular sense (& intero- & proprioception)
  – thus: perceptual richness, qualities
  – Other modes: imagery & dreaming (“internal”)
• Unity; ordering in a framework of space-time (experiencing being in an old artistic church rather than just seeing images)
  – perceiving only one scene at a time (situatedness)
  – All sensory inputs integrated into one, multimodal experience
• Sense of continuity; memory: embedding of present in past & future?
• Emotion, mood, feeling (perceptual, or other)?
• Volition, intention, motor activity?
• Sense of ‘I’ – self awareness?

Question 28

When can unity not occur

Answer 28

During LSD intake or if temporal distance between percepts is too large.

Question 29

What qualities of objects did John Locke distinguish?

Answer 29

Locke distinguished secondary and primary qualities of objects
*Primary properties can be measured, quantified (length, depth, motion, shape)
*Secondary: e.g. color and smell, heat, sound

Traditionally, secondary qualities would lack immediate ways of quantification and mechanistic accounts

Question 30

How has this primary-secondary distinction held up?

Answer 30

primary-secondary distinction has faded since Experiences can be qualitative and yet also quantifiable (e.g. depth) and there are mechanistic accounts of e.g. odor sensations.

Question 31

When talking about unity, how are there two different kinds of integration?

Answer 31

Visual disparity: two different images from both eyes => one view (with depth); stereoscopic depth.

Multimodal binding: e.g. coupling visual motion of right arm to proprioception from right but not left arm

Question 32

Apart from stereoscopic vision, where else is there visual disparity? (2)

Answer 32

Having a stable visual world view, despite saccades (jumping retinal image)
=> saccadic suppression: during eye movement, information is suppressed for perception
=> even with suppression in place, one has to blend images from t and t+1 into one percept

Binding problem- classically: within vision (e.g. shape & colour)

Question 33

What conjoined concepts may be responsible for consciousness?

Answer 33

Long-term memory and working memory may help to ensure a sense of continuity.

Question 34

Why might the feeling of continuity be partly illusory?

Answer 34

Feelings of continuity may be partly “illusory’ because the brain does not actively represent any gaps (e.g. during saccades, or in between remembered events)

Question 35

What is a neural correlate of the working memory?

Answer 35

“Delay activity” is a neural correlate of
working memory (see docs). It is found prominently in the lateral PFC, but also in other cortical areas (e.g. parietal, inferotemporal, primary visual). Can pertain to Cue properties, spatial info, semantic info.

Question 36

Evaluate the option of memory being required for consciousness?

Answer 36

Loss of long-term memory is devastating, but does not abolish consciousness. Patients do live on an “Island” of the Present: little connection to past and future (HM)

Question 37

How does Pennartz define emotions?

Answer 37

Emotions - complex sensorimotor events that comprise:
*sensory input due to trigger stimulus
*valuation & cognitive appraisal
*motor-readiness & actual response
*autonomous reactions & associated body
sensations (e.g. feeling sweaty)

Question 38

How can emotions be changed or otherwise affected?

Answer 38

Amygdala lesion: Klüver-Bucy syndrome
(loss of affect, fear, hypersexual, etc.)

Prefrontal damage: loss of spontaneity,
motivation, emotion, social rule-learning,
moral reasoning, executive decisions

Question 39

What affect do these emotionally damaging events have on consciousness?

Answer 39

These lesions do not impair consciousness/ perception per se, except that you also lose the body-sensory components of emotions (“feelings”; e.g. feeling sweaty).

Question 40

What does classic functionalism assert?

Answer 40

The Mind acts a causal intermediate between sensory inputs to behavioural outputs (= akin to: behaviourism). The mind is made up of dispositions/ attitudes/ beliefs to react to environmental changes with certain behaviours & narratives.

Question 41

What does functionalism posit about qualia?

Answer 41

Nothing special about Qualitative properties (Qualia):

“What science has actually shown us is just that the light-reflecting properties of objects cause creatures to go into various discriminative states, scattered about in their brains […]. These discriminative states of observers’ brains have various “primary” properties (……), and in virtue of these primary properties, they have various secondary, merely dispositional properties. In human creatures with language, for instance, these discriminative states often eventually dispose the creatures to express verbal judgments alluding to the “color” of various things”.

Question 42

Describe Capgras syndrome

Answer 42

Dissociability of emotion and perception; A Capgras patient labels a well-known person as an “impostor” of that person

Question 43

How has the explanation of capgras syndrome evolved over time?

Answer 43

First: Freudian explanations

Later: lack of emotional response to perceiving significant others; deficient communication between emotional and memory-identification neural systems

Question 44

Does Capgras system present evidence for or against functionalism? Why?

Answer 44

Against Dennett’s functionalism: perception can be dissociated from emotional disposition

Question 45

Why was it posited that motor activity was required for consciousness?

Answer 45

Llinas (2001): importance of active movement for cognition & consciousness. His example: adult sea squirts are sessile and have no brain. Larvae swim around freely and have a brain-like ganglion and spinal cord. Upshot: you only need a brain if you actively move around

Question 46

Evaluate this idea of movement required for consciousness

Answer 46

Consider Paramecium (bacteria)
* Stimulus-response reflexes: yes; calcium influx determines movement based on tactile response
* No evidence for goal-directed, planned behaviour
* No evidence for representations (scenes, multimodal integration)
* Occam’s razor: only include a term when the explanation demands it

Also:
=> Paralysis does not abolish consciousness
=> Locked-in syndrome after massive
stroke (move only e.g. left eye lid):
consciousness survives
=> Self study with paralysis poison
=> Phantom limb syndrome: experience
of amputated limb is still present

Question 47

How does phantom limb provide evidence against motor activity being required?

Answer 47

Even complete absence of motor activity (in a limb) does not abolish conscious experience for that limb (kinda dumb ngl)

Question 48

Some philosophers would posit we need language for consciousness. Evaluate this idea

Answer 48

Global aphasia can happen to people due to a massive stroke in e.g. Broca’s and Wernicke’s areas resulting in a complete loss of language. Patients are still conscious: facial expressions, other body language, gestures intact. There is also a reverse dissociation: linguistic expression can occur in absence of consciousness. Absence automatism is when epileptic patient performs complex actions (incl. linguistic) with vacuous facial expression; after recovery, patient is strongly surprised to find himself in the situation he is in and has no memory of it.