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Consciousness. Side dish or the whole shebang?. Sean Davis Erin Hecht Kris Tew Lydia Wood COGS 175 Spring 2005. Erin Definitions Philosophy & evolution Lydia Motor commands & social theory Kris Quantum physics & determinism Sean Meditation & “The Prime Mover”.
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Consciousness Side dish or the whole shebang? • Sean Davis Erin Hecht Kris Tew Lydia Wood • COGS 175 Spring 2005
Erin • Definitions • Philosophy & evolution Lydia • Motor commands & social theory Kris • Quantum physics & determinism Sean • Meditation & “The Prime Mover”
Introduction to the Debate About Consciousness Definitions, Philosophy and Evolution Erin Hecht
Definitions • Consciousness • Awareness; free will; qualia • Epiphenomenon • Dictionary: “A secondary phenomenon that results from and accompanies another” • Conscious epiphenomenalism: “Mental states are produced by physical states but have no causal role to play” – Blackmore 2004 • Physical Mental but NOT Mental Physical
Definitions • Causal • Mental Physical • The causal paradox: “Viewed from a first-person perspective, consciousness appears to be necessary for most forms of complex or novel processing. But viewed from a third-person perspective, consciousness does not appear to be necessary for any form of processing” - Max Velmans, quoted in Blackmore 2004
A thought experiment • Chalmers’s zombies • Humans without consciousness • “The hard problem” • Why do we exist instead of zombies? • Dennet’s zimboes • Zombies with recursive loops
Three ways to approach the evolution of consciousness 1. Epiphenomenalism or conscious inessentialism • Zombies are possible • Consciousness is separable from intelligence, memory, language, etc. & adding it to these abilities makes no difference in behavior of the organism. • The question: So how did we evolve?
Three ways to approach the evolution of consciousness 2. Consciousness serves an evolutionary function • Zombies are not possible • Consciousness is separate from other functions, but adding it makes a difference • The question: What is its evolutionary purpose?
Three ways to approach the evolution of consciousness 3. Functionalism • Zombies are not possible • Not separable from other functions; a conscious creature is a package deal (or consciousness = emergent property) • The question: How do these other functions give rise to consciousness?
Consciousness as a Causal Phenomenon Voluntary Motor Control Impact of Social Cognition Lydia Wood
Libet’s Argument • Motor plan initiation indicated by presence of Readiness Potential (RP) • RP found over central sensorimotor area (Cz) slow negativity preceding a movement • RP occurs ~500 ms before voluntary movement, self-reported decision to move occurs only ~200 ms before movement Libet et al. (1983)
Therefore… • The person becomes aware of the decision to move only after the motor plan has been initiated • Conscious decisions do not have a causal relationship with voluntary motor control • Are voluntary movements voluntary?
Problems With Libet’s Methods • Used average time of reported consciousness, instead of earliest time • Smearing effect produces skewed EEG avgs • RP more likely to reflect general readiness prior to an action than specific command to execute a particular action • Lateralized Readiness Potential (LRP) Trevarna and Miller (2002)
Trevana and Miller’s Results • Earliest decisions to move still occurred after onset of RP • 20% of people reported decision to move prior to mean LRP onset • Consciousness may play a causal role in the execution of an action Trevarna and Miller (2002)
Social Self-Awareness • Three parts of self-awareness • Sense of continuity • Sense of personal agency • Sense of identity • Self-awareness allows for introspectively based social strategies for competing and cooperating Gallup (1998)
What Can You Do With Consciousness? • Make mental object of self and other • Simulate counterfactual mental states based on previous experience (pretending) • Infer other mental states (empathy) • Modify behavior to take advantage of other mental states (deception)
Back to Zimbos Say there is a computer… • With subroutines that monitor operation of specific features • That then uses this information to make inferences about similar systems in other computers • And then modifies its own processing performance to gain competitive edge Gallup (1998)
Internal States and Determinism Heisenberg’s Uncertainty Principle and the Double Slit Kris Tew
Materialism to Determinism • Early 19th - 20th Century Materialism states only material things exist whose behavior is totally defined by the laws of physics. • Theoretically if you knew the position and momentum of all matter within a system everything done within that system could be predicted. • The human brain is composed of matter, the behavior of the brain is, in theory, predictable. • Problem: If only material things exist, either internal states like understanding must not exist or they must have a material component.
Heisenberg's Uncertainty Principle • It is not possible to know the exact position and momentum of matter. • The more precisely the position is determined the less precisely the momentum is known.
The Double Slit Experiment • Waves and the Interference Pattern • A single electron causes an interference pattern as if it was a wave
Inherent Randomness • Path selection and monitoring • Interference pattern vanishes • Waves to Bullets • Random selection
Heisenberg, Consciousness and Uncertainty • Monitoring the slits • Unpredictable change within a system • Internal states can exist within a material system because of uncertainty.
Consciousness as a Causal Phenomenon -Meditation Causes Physiological Changes -Consciousness is the Prime Mover Sean Davis
Meditation • Compassion meditation is a purely internal phenomenon • Meditation causes physiological changes • Perhaps physical states and mental states are the same
The Prime Mover • The stick hits the ball… the hand moves the stick… the arm moves the hand... where does it start? • Consciousness is the originator, or prime mover
Cognition is Distributed • Expectation and environment are the two major influences of a psychadelic experience • Maybe cognition exists outside the body
Thought Provoking Questions • Is consciousness epiphenomenal or causal? • What does it mean to have free will? How does it relate to determinism? • Are zimbos conscious? Zombies? Can they exist? • Is consciousness something that is individual, or socially distributed?
More questions • Fast or slow? • Tattersall: “any novelty has to arise spontaneously as an exaptation, a structure existing independently of any new function for which it might later be co-opted,” so consciousness arose “abruptly, as the by-product of something else” • Genetic or memetic? • Dennet: memeplex and selfplex; parallel processor with a serial virus (“the Joycean machine”) • Jaynes: Greeks and the bicameral mind
References Blackmore, Susan. (2004) Consciousness. Oxford University Press. Gallup, G. G. (1998). Self-awareness and the evolution of social intelligence. Behavioral Processes. 42, 239-247. Libet, B., Gleason, C. A., Wright, E. W., & Pearl, D. K. (1983). Time of conscious intention to act in relation to onset of cerebral activity (Readiness-Potential): The unconscious initiation of a freely voluntary act. Brain. 106, 623-642. Tattersall, Ian. (2004) What Happened in the Origin of Human Consciousness? The Anatomical Record (Part B: New Anat.) 276B: 19-26. Trevarna, J. A. & Miller, J. (2002). Cortical movement preparation before and after a conscious decision to move. Consciousness and Cognition. 11, 162-190. Wright, Robert. (1994) The Moral Animal. Vintage Books. Lutz, A. et al., (2004) Long-term meditators self-induce high-amplitude gamma synchrony during mental practice. PNAS, 101: 16369-16373 Newberg, A.B. and Iversen, J. (2003) The neural basis of the complex mental task of meditation: neurotransmitter and neurochemical considerations. Medical Hypotheses, 61(2): 282-291