ConsciousnessConsciousness

A Hard QuestionA Hard Question

New Area for PsychologyNew Area for Psychology Philosophers have long discussed Philosophers have long discussed

consciousness.consciousness. Descartes: Descartes:

Dualism—mind and brain are separate.Dualism—mind and brain are separate. Materialism (physicalism)Materialism (physicalism)

Mind and brain are one.Mind and brain are one. Consciousness is part of what the brain does.Consciousness is part of what the brain does.

Scientists are now trying to explore Scientists are now trying to explore consciousness empirically, seeing it as a consciousness empirically, seeing it as a product of the brain.product of the brain.

The debate: Will understanding how the The debate: Will understanding how the brain works mean that we will understand brain works mean that we will understand consciousness? consciousness?

Discuss These QuestionsDiscuss These Questions

What does it mean to be conscious?What does it mean to be conscious? Is language required to be conscious?Is language required to be conscious? How do we know if an organism is How do we know if an organism is

conscious?conscious? Are humans the only species to Are humans the only species to

experience consciousness?experience consciousness? Can a computer/robot ever be Can a computer/robot ever be

conscious?conscious? What is consciousness?What is consciousness?

The Difficulty for ScientistsThe Difficulty for Scientists

Philosophers argue that consciousness Philosophers argue that consciousness is:is: PrivatePrivate SubjectiveSubjective Peculiar to the individualPeculiar to the individual Cannot be directly observed by a 3Cannot be directly observed by a 3rdrd person. person. ““What it’s like to be me.”What it’s like to be me.”

How can we study this if we cannot How can we study this if we cannot define it in operational terms?define it in operational terms?

Elements of ConsciousnessElements of Consciousness The experience of consciousness cannot be The experience of consciousness cannot be

shared (shared (subjectivitysubjectivity).). Conscious experience is the product of Conscious experience is the product of

processes that we cannot access processes that we cannot access (access to (access to informationinformation))..

Consciousness pulls together our various Consciousness pulls together our various sensory experiences into one event sensory experiences into one event (unitary (unitary experienceexperience))..

We are aware of our consciousness We are aware of our consciousness (self-(self-knowledgeknowledge))..

Our conscious experience is shaped by Our conscious experience is shaped by previous experience previous experience (intentionality(intentionality))..

Areas of StudyAreas of Study

Perception without awareness Perception without awareness ((subliminal perceptionsubliminal perception).).

Brain-damaged individuals who have Brain-damaged individuals who have lost part of their consciousness:lost part of their consciousness: Blindsight (not knowing that we Blindsight (not knowing that we

perceived).perceived). AnosognosiaAnosognosia

Perception without Perception without AwarenessAwareness

Perception without Perception without AwarenessAwareness

Evidence:Evidence: Participants in many studies have been Participants in many studies have been

influenced by material flashed to quickly for influenced by material flashed to quickly for conscious awarenessconscious awareness

This influence is related to the meaning of the This influence is related to the meaning of the words.words.

Perception without Perception without AwarenessAwareness

Suggests that many of our decisions may Suggests that many of our decisions may be influenced by tings that we are be influenced by tings that we are unaware of:unaware of: Freudian slips:Freudian slips:

A play on words that may reveal a true desiresA play on words that may reveal a true desires

Example: A college photography teacher was Example: A college photography teacher was quite attracted to a handsome male student. quite attracted to a handsome male student. She made an embarrassing slip by asking him She made an embarrassing slip by asking him to step in to the "bed" with her, when she to step in to the "bed" with her, when she was in fact asking him to step into the hall. was in fact asking him to step into the hall.

What does this Freudian slip suggest?

What was he thinking as he greeted the audience?

We are unaware, i.e., unconscious, of the processes the create these slips.

BlindsightBlindsight Result of damage in the primary visual cortex/Result of damage in the primary visual cortex/ Individual has no sensation of light or colour from Individual has no sensation of light or colour from

the corresponding areas of the visual field—they the corresponding areas of the visual field—they say they cannot see an object placed in that part of say they cannot see an object placed in that part of the field.the field.

When asked to ‘guess’ where the object is they When asked to ‘guess’ where the object is they point quite accurately at rates well above chance. point quite accurately at rates well above chance.

Seems the brain gets some part of the visual Seems the brain gets some part of the visual information and guides behaviour even though they information and guides behaviour even though they do not see the object.do not see the object.

To experience blindsight, try the demo at:To experience blindsight, try the demo at:http://http://serendip.brynmawr.edu/bb/blindsight.htmlserendip.brynmawr.edu/bb/blindsight.html

AnosognosiaAnosognosia Result of damage in the right Result of damage in the right

hemisphere so that patient is hemisphere so that patient is paralyzed on left side of body.paralyzed on left side of body.

Still believe that the useless limbs Still believe that the useless limbs work perfectly well. work perfectly well.

Seem to lack awareness of the Seem to lack awareness of the paralysis when asked to use the limb.paralysis when asked to use the limb.

What Can We Learn?What Can We Learn? Conditions like blindsight and Conditions like blindsight and

anosognosia suggest that there may be anosognosia suggest that there may be areas of the brain responsible for areas of the brain responsible for conscious awareness.conscious awareness.

These conditions also tell us that there is These conditions also tell us that there is no one area responsible for no one area responsible for consciousness.consciousness.

Neuroscientists, using imaging techniques Neuroscientists, using imaging techniques are looking for patterns of neuronal firing are looking for patterns of neuronal firing that might lead us to find these areas. that might lead us to find these areas.