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

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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

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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

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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&current=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