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Janusz StarzykSchool of Electrical Engineering and Computer Science, Ohio University, USAwww.ent.ohiou.edu/~starzyk
Photo: https://www.adbusters.org/magazine/87/philosophy-zero-point.htmlhttp://www.geneang.com/Presence_Healing,_LLC/Neuroscience_of_Consciousness.html
Machine Consciousness Machine Consciousness
- A Computational Model- A Computational Model
Dilip PrasadSchool of Computer EngineeringNanyang Technological University, Singapore
ConsciousnessScientific perspectivePhilosophers’ perspectiveEmergence of consciousnessEvolution and consciousnessOur approach for machine consciousnessConsciousness: functional requirementsDefinition of machine consciousnessComputational modelComputational model: implications
OutlineOutline
Photo: http://tsvetankapetrova.wordpress.com/2009/06/30/5-setbacks-that-stop-you-big-time/
Description of ConsciousnessDescription of Consciousness
The quality or state of being aware especially of something within oneself from Merriam Webster Dictionary
Nobody has a slightest idea of how anything material can be conscious – J.A Fodor
…our subjective experience or conscious state involving awareness, attention, and self reference - Jeanette Norden.
Anything that we are aware of at a given moment forms part of our consciousness, making conscious experience at once the most familiar and most mysterious aspect of our lives - Velmans
Photo: http://www.amazon.com/Great-Courses-Jeanette-Norden/dp/159803362X/ref=pd_rhf_p_t_2
Scientific perspectiveScientific perspective
It may be pointless trying to define consciousness, its evolution or function as they may have many different interpretations, similar to other big words like perception, learning, knowledge, attention, etc – Sloman
Consciousness refers to focusing attention, mental rehearsal, thinking, decision making, awareness, alerted state of mind, voluntary actions and subliminal priming, concept of self and internal talk – Calvin & Ojemann
Consciousness is a combination of self awareness and qualia and memory plays an important role in it – Jeff Hawkins
Consciousness is a dynamic process and it changes with development of brain. Further, at macro-level there is no consciousness centre and at micro-level there are no committed neurons or genes dedicated to consciousness – Susan Greenfield
Philosophers’ perspectivePhilosophers’ perspective
Phenomenally conscious states are those states that possess fine-grained intentional contents of which the subject is aware, being the target or potential target of some sort of higher-order representation – Rosenthal (Higher Order Theory)
Consciousness is accomplished by a distributed society of specialists that is equipped with working memory, called a global workspace, whose contents can be broadcast to the system as a whole – Baars
…various events of content-fixation occurring in various places at various times in the brain ... there is no single place in brain for consciousness – Dennett
Nisargadatta states that awareness is not a part (subset) of consciousness but instead it is its superset
Emergence of ConsciousnessEmergence of Consciousness
Week Human Fetus brain development
6 Cortical cells come at the correct position
20 Cortical region is insulated with myelin sheath
25 Development of local connections between neurons
30 Fetus’ brain generates electrical wave patterns
Conclusion : Emergence of consciousness is a gradual process
Photos: http://daymix.com/Fetus-Brain-Development/http://www.humanillnesses.com/Behavioral-Health-A-Br/The-Brain-and-Nervous-System.html?Comments[do]=mod&Comments[id]=1
Evolution and consciousness Evolution and consciousness – appearance and evolution of consciousness– appearance and evolution of consciousness
Living Being Evolutionary traitsAnalogous feasibility in machines
Human
Beings
Fully developed cross-modal representation
Sensory capabilities: auditory, taste, touch,
vision, etc.
Bi-frontal cortex: planning, thought, motivation
Impossible at
present
Hedgehog
(earliest
mammals)
Cross-modal representation
Sensory capabilities: auditory, touch, vision (less
developed), etc.
Small frontal cortex
Impossible at
present
Birds
Primitive cross-modal representation
Sensory capabilities: auditory, touch, vision,
olfactory.
Primitive associative memory
Associative
memories
Photos: http://images.google.com/
Evolution and consciousness Evolution and consciousness –absence of consciousness–absence of consciousness
Living Being Evolutionary traitsAnalogous feasibility in machines
Reptiles*Olfactory systemPrimitive vision
Computer vision (nascent)
Hagfish (early vertebrate)
Primitive olfactory systemPrimitive nervous system
Artificial neural networks
Lower level animals
(hydra, sponge, etc.)
Sensory motor unitsPoint to point nervous
system
Mechanical and/or electronic control systems
* inconclusive\consciousness in transition
Exceptional cases -> Octopus(memory & learning skill), Circadian sleep wake cycle of insects (crude state of consciousness), etc.
Photos: http://images.google.com/
Our approach for Our approach for machine consciousnessmachine consciousness
Define consciousness in functional terms
Identify minimum functional requirements
Identify minimum functional blocks, their individual roles, their inter-relationship
A computational model
Photo: http://www.theglobalintelligencer.com/aug2007/fringe
Consciousness: Consciousness: functional requirementsfunctional requirementsIntelligence
• Mechanism to acquire and represent Knowledge
• Knowledge is a result of learning
Attention and attention SwitchingCognitive perception and related action
• Semantic memory
• Associative sensory-motor memory
• Episodic memory – not necessary
Cognitive awarenessCentral executive
Photo: http://eduspaces.net/csessums/weblog/11712.html
Computational Models of IntelligenceComputational Models of Intelligence
Not necessary alive Consciousness requires
– Intelligence (ability)– Awareness (state)
How to define and compute intelligence?
Embodied IntelligenceEmbodied Intelligence
– Mechanism: biological, mechanical or virtual agent
with embodied sensors and actuators– EI acts on environment and perceives its actions– Environment hostility is persistent and stimulates EI to act– Hostility: direct aggression, pain, scarce resources, etc– EI learns so it must have associative self-organizing memory– Knowledge is acquired by EI
Definition Embodied Intelligence (EI) is a
mechanism that learns how to minimize hostility of its environment
Motivated LearningMotivated Learning
Various pains and external signals compete for attention. Attention switching results from competition. Cognitive perception is aided by winner of competition.
Definition: Motivated learning (ML) is pain based motivation, goal creation and learning in embodied agent. Machine creates abstract goals based on the
primitive pain signals. It receives internal rewards for satisfying its goals
(both primitive and abstract). ML applies to EI working in a hostile environment.
AttentionAttentionSelective process of
cognitive perception/action
other cognitive experiences like
thoughts, action planning, expectations, dreams
Result of attention switching needed to have cognitive experience
leads to a sequence of cognitive experiences
Comic: http://lonewolflibrarian.wordpress.com/2009/08/05/attention-and-distraction-what-are-you-paying-attention-to-08-05-09/
Attention Switching !!!Attention Switching !!!
Dynamic process resulting from competition between• representations related to motivations
• sensory inputs
• internal thoughts including spurious signals (like noise).
May be a result of • deliberate cognitive experience (and thus fully conscious signal)
• subconscious process (stimulated by internal or external signals)
Thus, while paying attention is a conscious experience, switching attention does not have to be.
Photo: http://lonewolflibrarian.wordpress.com/2009/10/page/3/
Central ExecutiveCentral ExecutiveOperates no matter whether machine is conscious or notPlatform for the emergence, control, and manifestation of consciousnessControl its conscious and subconscious processesDriven by
learning mechanism creation and selection of
motivations and goals
Central executive, by relating cognitive experience to internal
motivations and plans, creates self-awareness and conscious
state of mind.
Definition of Machine ConsciousnessDefinition of Machine Consciousness
A machine is conscious IF besides the required components
for perception, action, and associative memory, it has a
central executive that controls all the processes (conscious
or subconscious) of the machine;
The central executive is driven by the machine’s attention
switching, motivation goal selection, and learning
mechanism, and uses cognitive perception and
understanding of motivations, thoughts, or plans.
Photo: www.spectrum.ieee.org/.../biorobot11f-thumb.jpg
Computational Model of Machine ConsciousnessComputational Model of Machine Consciousness
Semantic memory
Sensory processors
Data encoders/ decoders
Sensory units
Motor skills
Motor processors
Data encoders/ decoders
Motor units
Emotions, rewards, and sub-cortical
processing
Attention switching
Action monitoring
Motivation and goal processor
Planning and thinking
Episodic memory
Queuing and organization of episodes
Episodic Memory & Learning
Central Executive
Sensory-motor
Inspiration: human brainInspiration: human brainPhoto (brain): http://www.scholarpedia.org/article/Neuronal_correlates_of_consciousness
Sensory- Sensory- Motor BlockMotor Block
Semantic memory
Sensory processors
Data encoders/ decoders
Sensory units
Motor skills
Motor processors
Data encoders/ decoders
Motor units
Emotions, rewards, and sub-cortical processing
Sensory-motor
sensory processors integrated with semantic memorymotor processors integrated with motor skillssub-cortical processor integrated with emotions and rewards
Multiple processors, parallel processing, multiple individual outputs
Central ExecutiveCentral ExecutiveAttention switching
Action monitoring
Motivation and goal processor
Planning and thinking
Central Executive
interacts with other units for o performing its tasks o gathering data o giving directions to other units
no clearly identified decision centerdecision influenced by
o competing signals representing motivations, pains, desires, and attention switching
• need not be cognitive or consciously realizedo competition can be interrupted by attention switching signal
Central ExecutiveCentral ExecutiveAttention switching
Action monitoring
Motivation and goal processor
Planning and thinking
Central Executive
Taskso cognitive perceptiono attentiono attention switchingo motivationo goal creation and selectiono thoughtso planningo learning, etc.
Requireso capability to dynamically
select and directly execute programs
o capability to activate semantic memory and control emotions
Computational Model: ImplicationsComputational Model: ImplicationsThe motivations for actions are physically distributed
o competing signals are generated in various parts of machine’s mind
Before a winner is selected, machine does not interpret the meaning of competing signals Cognitive processing is predominantly sequential
o winner of the internal competition serves as an instantaneous director of the cognitive thought process, before it is replaced by another winner
Top down activation for perception, planning, internal thought or motor functions
o results in conscious experience• decision of what is observed• planning how to respond
o a continuous train of such experiences constitutes consciousness
Photo: http://www.prlog.org/10313829-homeless-man-earns-250000-after-viewing-prosperity-consciousness-video-subliminal-mind-training.html
ReferencesReferences J. A. Fodor, "The big idea: can there be science of the mind," Times
Literary Supplement, pp. 5-7, July 1992. J. Norden, Understanding the brain, Video lecture series. M. Velmans, "Where experiences are: Dualist, physicalist, enactive and
reflexive accounts of phenomenal consciousness," Phenomenology and the Cognitive Sciences, vol. 6, pp. 547-563, 2007
A. Sloman, "Developing concept of consciousness," Behavioral and Brain Sciences, vol. 14 (4), pp. 694-695, Dec 1991.
W. H. Calvin and G. A. Ojemann, Conversation with Neil's brain: the neural nature of thought and language: Addison-Wesley, 1994.
J. Hawkins and S. Blakeslee, On intelligence. New York: Henry Holt & Company, LLC., 2004.
S. Greenfield, The private life of the brain. New York: John Wiley & Sons, Inc., 2000.
Nisargadatta, I am that. Bombay: Chetana Publishing, 1973. D. C. Dennett, Consciousness Explained, Penguin Press,1993. D. M. Rosenthal, The nature of Mind, Oxford University Press, 1991. B. J. Baars “A cognitive theory of consciousness,” Cambridge
University Press, 1998.Photo: http://s121.photobucket.com/albums/o209/TiTekty/?action=view¤t=hist_sci_image1.jpg
Questions ??Questions ??
Photo: http://bajan.wordpress.com/2010/03/03/dont-blame-life-blame-the-way-how-you-live-it/
Embodiment
Actuators
Sensors
Intelligence core
channel
channel
Embodiment
Sensors
Intelligence core
Environment
channel
channelActuators
Embodiment
Actuators
Sensors
Intelligence core
channel
channel
Embodiment
Sensors
Intelligence core
Environment
channel
channelActuators
Embodiment of a MindEmbodiment of a Mind
Embodiment is a part of the environment that EI controls to interact with the rest of the environment
It contains intelligence core and sensory motor interfaces under its control
Necessary for development of intelligence
Not necessarily constant or in the form of a physical body
Boundary transforms modifying brain’s self-determination
Brain learns own body’s dynamic Self-awareness is a result of
identification with own embodiment Embodiment can be extended by
using tools and machines Successful operation is a function
of correct perception of environment and own embodiment
Embodiment of a MindEmbodiment of a Mind
Pain-center and Goal CreationPain-center and Goal Creation
Simple Mechanism Creates hierarchy of
values Motivation is to reduce
the primitive pain level Leads to formulation of
complex goals Reinforcement :
• Pain increase• Pain decrease
Forces exploration
+
-
Environment
Sensor
MotorPain level
Dual pain levelPain increase
Pain decrease
(-)
(+)
Motivation
(-)
(-)
(+)
(+)
(+)
(-)
Goal
Primitive Goal CreationPrimitive Goal Creation
- +
Pain
Dry soilPrimitive
level
opentank
sit on garbage
refillfaucet
w. can water
Dual pain
Reinforcing a proper action
Wall-E’s goal is to keep his plants from dying
Abstract Goal HierarchyAbstract Goal Hierarchy
Abstract goals are created to reduce abstract pains and to satisfy the primitive goals A hierarchy of abstract goals is created to satisfy the lower level goals
ActivationStimulationInhibitionReinforcementEchoNeedExpectation
- +
+
Dry soilPrimitive Level
Level I
Level IIfaucet
-
w. can
open
water
+
Sensory pathway(perception, sense)
Motor pathway(action, reaction)
Level IIItank
-
refill
Reinforcement LearningReinforcement Learning Motivated Learning Motivated Learning Single value function Measurable rewards
Can be optimized
Predictable Objectives set by
designer Maximizes the reward
Potentially unstable
Learning effort increases with complexity
Always active
Multiple value functions One for each goal
Internal rewards Cannot be optimized
Unpredictable Sets its own objectives Solves minimax problem
Always stable
Learns better in complex environment than RL
Acts when needed
http://www.bradfordvts.co.uk/images/goal.jpg