Problems of Conscious Flashcards
Everything your mind has even known…
originated as info from your body’s senses
Descartes
- “I think, therefor I am”
- For Descartes, his mind was proof of his existence
- Even if a god was deceiving him, only a mind can be deceived
- So, even if his perceptions were wrong about physical world
- His Consciousness meant he existed
Dualism
- Mind exists as something separate
- But… difficulty explaining how minds interact to make bodies active
Monism
- Mind is a by-product of active bodies
- But… suggests that minds are illusions
Panpsychism
- Everything contains both physical and mental aspects
- Minds are real, but vary in complexity
- A rock’s “mind” is less complex than a human mind
- But… how do individual “minds” combine into one?
The brain as a collection of parts you can
lose parts of your brain - by losing brain functions
THe “Easy” Problem of consciousness
Research in psychology and neurosciences
- Testing cognitive abilities
- Identifying functions of specific brain areas
- Studying predictors of behavior
The “Hard” Problem of consciousness
- Why do our experiences feel the way they do?
- How do neurons firing equal subjective experiences?
- How do we find answers to the Mind-Body problem?
A neuroscientist’s explanation of consciousness
- “Conscious states are associated with synchronized oscillations of neuron clusters”
The Music of Consciousness - analogy
brain is an orchestra
- Many different instruments
- Different brain areas
- Each instrument can perform by itself
- Brain areas can function independently
- But when instruments play in harmony…
- “Synchronized oscillations of neuron clusters”
Neural Correlates of consciousness (NCC)
- Attempts to find the brain regions and patterns of activity that correspond to conscious experiences
The Binding Problem
- How does the brain unify all the individual pievees to feel like one continuous experience?
Feel like we are experiencing everything at once
But… our brains process everything separately
- Color, shape, motion, location
- All processed independently
Neuronal assemblies
- Networks of neurons that fire at the same rate and frequency
- Each assembly may correspond to one aspect of perception
- The assembly that responds to my face is a separate from the assembly that responds to my shirt
- Each assembly may correspond to one aspect of perception
- Gamma Oscillations
- Neuronal assemblies oscilliate a certain frequency
- 40 hz (per sec)
- The electric signal can back-propogate
- Waves of electric signal moving back and forth
- Ths is simlliar to the electricity in your house
- Electrical appliances run at 60 hz
- If viewing an image of a green suitcase and blue hat
- Neurons responding to the hat fire in snyc
- Neurons responding to the suitcase respond in sync
Orchestra of the Mind
What we are consciously aware of at any given moment is determined by which “neuronal assemblies” are synchronized at the moment
- Paying attention to one thing or the other changes “increases the volume” of difference synchronized groups
- For instance, attention on the green suitcase vs. attention on the blue hat
Default Mode Network
- A network of connected brain area that are most commonly active while conscious
- The default mode network refers to which areas of your brain are active when you’re awake but not doing anything in particular
Mental feelings vs. Mental control
- The default mode network are the brain areas most activated from simply being conscious
- The two most active of the cortex are in the frontal lobe and around the temporal-parietal junction
- The actual “feeling” of being conscious may be due to activity around the TPJ
- While our feeling of being “you” and in control of your mind is due to the frontal lobe activity
COunsciousness is complexity
- Conscious states are associated with highly completed activity between brain areas
- Even if different collection of neurons are in snyc, the patterns are complex
- Orchestra analogy
- Conscious states
- The orchestra is playing a complicated song with many melodies and tempos
- Unconscious states “dead brain”
- The orchestra is playing one long monotonous sound
- Conscious states
- Neuroscience can measure the complexity needed to create conscious states
- Amount of “perturbational complexity” in brain activity
- Measured using TMS (transcranial magnetic stimulation)
- The measure is known by the Greek letter Phi
- This measure can help determine whether people in comas or persistent vegetative states (i.e. brain dead) are having conscious experiences
- Most people in vegetative states appear to be permanently unconscious
- But, some have complex activity indicitating consciousness
- They maybe conscious but “trapped” in their bodies and unable to communicate
- But, some have complex activity indicitating consciousness
- Our conscious minds may only be observers of what our brains decide to do
- Libet’s study of Free Will
- Brain prepares to move before conscious awareness of deciding to move- Split-brain patients
- Left brain confabulates explanation for what the right brain controlled
- Split-brain patients
Libet’s Study of Delayed Awareness
- Studies done on people who had to get brain surgery
- Studies were conducted while the brain was exposed
- Studies involved
- Direct stimulation of somatosensory cortex
- Electrode in brain’s primary receiving area for touch
- Direct stimulation of skin
- A poke to the hands
- Participants report if and/or when they felt anything
- Direct stimulation of somatosensory cortex
Libet’s experiment
- Poke the hand
- Participant reports feeling hand be touched
- Stimulate the “hand” area of the brain for more than 500 milliseconds
- Participant reports feeling hand being touched
- (Doesn’t feel quite like a hand)
- Participant reports feeling hand being touched
- Stimulate “hand” area of brain for less than 500 milliseconds
- Participant reports feeling nothing at all
Libet’s conclusion Neuronal Adequacy
- Sensory experiences only become conscious if the sensory cortex is active for at least 500 ms
- It takes half a second of brain activity for sensory experiences to enter consciousness
- To achieve “neuronal adequacy”
- It takes half a second of brain activity for sensory experiences to enter consciousness
- “Attention” to any sensation must occur half a second behind the actual experience
