Lecture 1

Question 1

Consciousness conclusion

Answer 1

We still dont know what consciousness is or how it works. It seems to involve a host of neural processes and some magic or something we dont get.

Question 2

Definition consciousness

Answer 2

the state or quality of awareness - awareness of your thoughts, perceptions, memories and feelings

Question 3

Why do neuroscientists believe that consciousness and the mind arise from neural processes?

Do we have an answer?

Answer 3

Consciousness can be changed by physical or chemical changes within the brain (damage or drugs).

Studies have not been conclusive but have taught us some things

Question 4

The frontal lobotomy

Answer 4

Cot of parts of the prefrontal cotex with a giant pick

Same rational as gangrene; cut out the affected part

Makes people docile

Was popularized by travelling doctors

Nobel prize awarded

20000 done in the USA

Question 5

Generalized epileptic seizure

Answer 5

Uncontrolled excitement on both sides of the brain

Question 6

Split-brain operation

Answer 6

Designed to lessen epilepsy
cut corpus callosum and the posterior and anterior commisures

Generally works for epilepsy but unacceptable sides

Question 7

Cerebral hemispheres are important for

Answer 7

ability to consciously process sensory information, purposefully move our bodies

contralateral arrangement

Question 8

Eye organisation

Answer 8

right visual field to left brain

left visual field to right brain

Question 9

Corpus callosum

Answer 9

bridge between two hemispheres

allows for each to know what the other is doing

if cut, cannot

can still send signals down to midbrain, hindbrain and spinal chord to control muscles

Question 10

History of the spit-brain surgery

Answer 10

in 1939, 10 patients had surgery in Rochester, NY
Doc said this was an amazing success

Scientists re evaluated them
1 - claims exagerrated
2 - Corpus callosum not impoirtant for anything

Roger Sparry at Caltech did not agree as he had done this to animals and they produced characteristic effects. He thought there was probably still some bridges intact.

He was invited to do pre and post surgery investigations at Caltech when a surgeon there was going to do it.

Question 11

Split-brain patients reported

Answer 11

feeling the same after

but having their left hand misbehaving as if it were not under their conscious control. This implies the right hemisphere is acting out
Right hand did not

Question 12

Viki

Answer 12

issues with right hand fighting her in supermarket and when getting dressed. After a year got better. Common for these patients

Question 13

Split-brain patients - touch

Answer 13

Cannot ID objects in left hand by touch alone

Did not bother them as very rare that this happens so might go unnoticed.

Question 14

Split-brain patients - vision

Answer 14

When shown object in their left visual field only, cannot verbalize what they have seen. They are unconscious of what their right brain deals with

They compensate behaviorally and their hemispheres adapt

Motor is coordinated at the subcortical level so with practice can do it

Question 15

Language and brain

Answer 15

right not sophisticated with language

Can understand simple qs directed to right brain - it retains a small dictionary and can understand simple letters. The left hand can sometimes over write simple words.

Can still draw though

Question 16

Split-brain experiments - Questions

Answer 16

Have person fixate on a point

Present an object either to the left or the right of the focal point for 200ms so that it is not long enough to focus on it.

Ask if object is present

1) if the object is in the left visual field they say no because this goes to the right and so the person is unaware
2) if the object is in the RVF, they say yes as this goes to the left hemisphere which is aware
3) if you show two objects, one to the left and one to the right of the focal point and ask if they are the same, the participant will say they do not know.

Question 17

Split-brain experiments - objects and words

Answer 17

If you put two words either side of the focal point, like KEY to the left and RING to the right and ask them what the word is, they will say RING as this goes to the left hemisphere. IF however you ask them to take the object that corresponds to the word on the left, using touch (in this case KEY), using their left hand, they will find a key as the right hemisphere has seen the world key.

This will be a great shock to them and they will not know why they did it. They will believe their hand probably found a ring as that is the word they are conscious of.

Question 18

Post-hoc answers

Answer 18

When asked to explain why people did what they did after their right brain is prompted to do something (that is outside of their conscious control), they make something up that justifies it.

Eg, Right brain prompted to laugh, person says he laughed cos they’re always testing him and its funny

Question 19

Gazzaniga’s Interpreter Theory

Answer 19

Our behaviour is controlled by inconscious processes and the consciousness of our left brain is just making narratives to make sense of the world. Left-brain consciousness doesn’t influence behavior, it just weaves things together to make a story that has meaning.

Therefore free will is an illusion. Consciousness is just storytelling. Since storytelling relies on language, consciousness must only located in the left hemisphere.

It is an epiphenomenon

Question 20

Scientific revolution and acceptance of determinism

Answer 20

As science grew during the revolution, we have become comfortable accepting that the world is just an unbroken chain of cause and consequence.

Question 21

Descarts

Answer 21

In the middle of the sci revolution, Descartes started questioning everything. If our perceptions are misleading, what can we trust?

He decided “I think, therefore I am”

The only thing we can know to be true is that we have the ability to think and for this to be true, Descartes argued, consciousness must be real because we must be conscious to exist.

Question 22

Important outstanding questions in the field

Answer 22

1) how do we feel things
2) what is thinking and how does it work?
3) What is mental illness

Question 23

Profs attitude to interpreter thinking

Answer 23

Its wring

We do not know what consciousness is yet, we should first understand that then work out free will

Question 24

What we know (4 things)

Answer 24

What brain is made of and how things work at the cellular level

How neurons communicate

How sensory stimuli is transduced and initially processed

The last few cells in the motor system pathway

Question 25

What we dont know (few cells deep)

Answer 25

after a few cells deep we have no idea what is happening or how info is processed.

Very limited understanding of the neural bases of emotion, cognition, consciousness, decision making etc

Question 26

Dali Lhama and Jill Bolte Taylor

Answer 26

Lama meditates to achieve higher awareness

Jill had a stroke that disabled her language processing on the left hemisphere and found herself feeling more aware until her left brain came back online.

Possible that consciousness does not require language

Others disagree and say they’re totally intertwined.