# 2014 Consciousness and the brain - Deciphering how the brain codes our thoughts

## Introduction: The Stuff of Thought

Progress in consciousness is due to three factors:
 1. better definition of consciousness
 2. the possibility of experimental manipulation
 3. respecting subjective phenomena

## 1 Consciousness Enters the Lab

Science proceeds by creating better definitions. 
Consciousness usually involves 3 distinct concepts:
 1. vigilance, being awake
 2. attention, focusing mental resources on a single piece of information
 3. conscious access, we can see and report to others, crossing the border between unperceived and perceived

Not considering the more complex issues (self-consciousness, free will), conscious access is a good start.

Conscious access: we are limited to have one thought at a time, despite the information load from the senses.

minimal contrast: two experimental setup with little difference but only one of them is consciously perceived.

 "...studying what happens as behaviour automatizes sheds light on the transition from conscious to unconscious" p26
 
 Binocular rivalry.
 
 "Conscious access imposes a narrow bottleneck." p33 - too slow to keep up with fast sensory changes.
 
 Inattention makes any object vanish from our consciousness. e.g. the gorilla 
 
## 2 Fathoming unconscious depths

How deep can an invisible image travel into the brain?

All brain regions can participate both in conscious and unconscious operation.

 "Uninformed of the inner workings of our vision, we believe that the brain works hard only when we feel that we are working hard—for instance, when we’re doing math or playing chess." p60

"The unconscious mind proposes while the conscious mind selects." p66

vision and semantic processing can be unconscious

"some aspects of problem solving are better dealt with at the fringes of unconsciousness rather than with a full-blown conscious effort. We are not entirely wrong when we think that sleeping on a problem or letting our mind wander in the shower can produce brilliant insights." p82

sleeping is needed for the consolidation of knowledge

## 3 What is consciousness good for?

Why did consciousness evolve? Are there operations that can be carried out only by a conscious mind?

Conscious information is stable - it allows us to keep a thought and do something with it.

Is it an epiphenomenon? Just a useless by-product?

Conscious access always have a single view of the world, despite the Bayesian uncertainty of the sensory data.
A bit like in quantum theory, an observation collapses the probability distributions.

Lasting thoughts - the capacity for retrieving and rethinking information should have an evolutionary advantage. Learning over time rather than living in an instant.

The human Turing machine - consciousness gives this serial central processing unit.

Social knowledge sharing.