On Intelligence Jeff Hawkins
The Evolution of Intelligence
Evolution - Traits within populations change over
time. To have evolution you need to have
heritable traits and there needs to be variability among these traits and some
versions need to work better than some others. This is about reproduction of the most
adapted, not survival - the number of copies of the gene that get passed on. The chicken is a device used by the egg to
produce another chicken. There is equal
value in saving 8 cousins to reproduce as one brother as they both have the
same number of your genes. In addition,
if every now and then there is mutation of a new trait, this can leave to a
change of population. Evolution is not
an inventor but a tinkerer
Intelligence –
Our brains use memories to form predictions about everything we see, feel, and
hear. The brain also constantly makes predictions about the world. When these come true that is
understanding. If they do not that is
confusion.
Starting 3.8 billion years ago and for 2 billion years thereafter
single cell life was the highest order intelligence on earth.
Single-celled organisms move in response to light, heat and chemical gradients
toward a more favorable environment. This was the first kind primitive behavior, which
was transmitted through DNA.
Plants use DNA to remember and they use
hormones to fend off invading organisms, trigger flowering, and direct growth. Using DNA evolution to adapt to the
environment takes generations and individuals do not learn to adapt.
Lizard
Brain
Before there was intelligence there was
behavior. Reptiles conquered the land after the Permian extinction, 248 million
yeas ago, when the earth was hot and there was no polar ice cap. The reptile brain handles aggression, mating,
breathing, heart rate, sleeping, temperature, hunger, and reaction to
danger. Our brain contains a reptile
brain and you can see this lizard brain at work in babies. However, reptiles don’t learn.
Cat
Brain
200 million years ago lived the first
mammals but mammalian life exploded 65 million years ago with the extinction of
the dinosaurs and the first primates which appeared around 50 million years
ago.
Reptiles are solitary animals. Mammals inherited the reptile brain and added
new features, a limbic system, which contained brain structures for making
social interactions. Early mammals lived
in groups and animals that were better at living with others reproduced
more. It facilitates relationships such
as mother- child, which is critical since mammals need to feed their
young. These structures included
hypothalamus, the hippocampus, the amygdala, and others. This lets mammals have good feelings about
another mammal. All mammals have a
cortex but in most it is small. Most
conduct their social lives without much words or cortex and rely on the
neurochemical response they were born with or learned in infancy. In mammals hormones and neurotransmitters
work together in pursuit of status and happiness. The limbic system also facilitates our stress response to danger and
memory of things that are dangerous.
The Limbic system does not talk in
words but communicates to the rest of the brain by secreting happy (dopamine) or
unhappy chemicals
In most mammals smell is the dominant
sense. The Olfactory bulb makes up 40%
of the brain of a rodent. Ours is 5% of
our brain. The rat’s emotions are smell driven. Children live
through their limbic brain, as their prefrontal cortex isn’t fully mylinated
until age 25. http://www.youtube.com/watch?v=CAOnSbDSaOw
In humans under stress the limbic
system influences the cortex. Conversely
memories from the cortex also influence the limbic system. You can demonstrate this by thinking about
your death. In most people this causes
anxiety. Humans often have a limbic
response to imagined stresses.
The entire limbic system is designed to
influence hypothalamic function (endocrine and autonomic system), which is how
the limbic system influences behavior. The
closer a nucleus (subpart of the limbic system) or sense is to hypothalamus (few
synapses) the more influence it has on the hypothalamus. Each of our senses
except olfaction needs 4 synapses to reach the limbic system. Visual input has to go through 4 levels before
the information is transmitted. Tourette’s
syndrome is an over activity of the limbic system
It is important to note that the limbic
system does not use words. It tells your
body what it is up to by releasing chemicals.
We feel the effects of these.
Adrenaline makes our heartbeat rapid, which we can sense.
Some parts of the Human Limbic System
include
Amygdala
- causes fear, anxiety, learning to be afraid, rage, and
aggression. You need fear to cause
aggression. The amygdala is found to get
larger in people with PTSD the parts can enlarge. It is involved in fear and anxiety and
aggression. It is also involved in male sexual motivation.
Septum
- inhibits aggression
and opposes the amygdala.
Hippocampus
- helps you learn
remember. In depression this shrinks. Also it can turn off the stress
response. It is involved with stress so
it can make sure you remember things which cause stress and how you got out of
it. The hippocampus sits on top of the
cortical pyramid. The neocortex is
sandwiched between the limbic system and the hippocampus. When sensory input comes in lower levels of
your cortex see if they recognize it. If they don’t they send it up to the next
level. Only if it gets to the
hippocampus is it then sent back to the cortex for storage.
Lateral
hypothalamus – has to do with hunger. Measures
glucose levels. Hungers for other
rewards other than food.
Mammillary
bodies - are related to maternal behavior
Thalamus
Ventral
tegmental area and Nucleus accumbans - this is
the pleasure center which releases dopamine. All addictive drugs work here. And it is involved with repetitive
behavior. It is the part that activates
when you anticipate getting pleasure or a reward. It powers the behavior to get the award. Gives you motivation to carry out the pursuit
of pleasure. Note that the pursuit of pleasure
is more addictive than the pleasure. All
addictive behaviors
Prefrontal
cortex- this is a cortical component of the
limbic system.
It teaches when to be aggressive. It doesn’t fully myelinate until age 25. It
is important for gratification postponement
Anterior
cingulate cortex – has to do with maturation, learning, and when
to be aggressive. it also handles empathy
and feeling others pain. If you watch someone’s finger being poked you feel his
or her pain. It is also related to
depression.
Across 150 primate species. The biggest predictor is how large is the
average social group of this species.
This evolved for gossip, social intelligence and behavior.
According to the James Lange theory – if a stimulus
comes to your brain, your body responds before you feel it. Your body gets information from the periphery
and that how you know you are afraid. This is how your brain decides what emotion
you are feeling. Adrenalin is released
by an aroused sympathetic nervous system.
It kicks up level of whatever emotion you are feeling. It magnifies the emotion. Anxiety is felt by getting feedback from your
body. Valium works as a muscle relaxant
to block this feedback. Biofeedback and
meditation also work to reduce this feedback.
If you take someone with depression and
make them smile. After a half hour they
feel better. Their body is getting
feedback it must not be so bad.
Another example:
You and significant other are reacting
to some situation. You make your spouse furious. You apologize. It’s ok. Then your spouse remembers something
you did in 1968 and starts arguing again. .
When you get into an aroused, angry state it takes minutes for the
sympathetic nervous system to equilibrate.
I am still feeling agitated. The physiologic
data comes back and you try to find a cognitive reason for it.
This is because females take longer to get
their equilibrium back. This is also
after true after an organism, guys.
Human
Brain
The
Neocortex
It was 7 million years ago that the
first bipedal ape from which we evolved appeared. Then, only 200000 years ago a
mutation leading to a 30% increase in brain size occurred. The main difference between the human brain
and other primate brain is the quantity of neurons. As a part of this evolutionary breakthrough,
connections between neurons became modifiable.
Due to this, behavior could change within a single lifetime. A mammal could learn the structure of its
world within its lifetime. The
modifiable nervous system enabled the formation of memory.
Taking on a
memory system lets animals predict the future.
If you toss a Nerf ball at a reptile it
always ducks.
Once we are hit and
experience that nothing bad happens we learn and stop ducking.
When
an animal encounters a similar situation memory recognizes that and remembers
what happened.
It remembers the
behavior that led to that outcome. Thus memory lets the animal use its
behaviors more intelligently.
This led
to an evolutionary advantage.
The biggest advance of mammalian development was the
developmentof a neocortex.
This memory machine does
not work like a computer.
It recalls
patterns auto associatively, that is it can recall the whole output with a
partial input.
Most people can recognize
Beethoven’s 5
th symphony by the fourth note.
The cortex stores sequences of patterns and it stores them
in a hierarchy. The neocortex in rats
is the size of postage stamp. In humans
it is the size of a dinner napkin and contains 30 billion neurons. It is only 6
business cards thick (6 layers) and homogenous at birth. All areas of the cortex work the same way
including both the motor and sensory areas.
The brain uses the same processes to see, hear, and feel. To the brain all senses are the same, just
temporal inputs of patterns. All
knowledge and memories are stored in your neocortex. This is you.
Memory is structural that is protein based, not electrical. You can cool the brain down until all
electrical activity stops and then bring it back and the memories persist.
When you are born your cortex knows nothing. It’s a blank disc. Learning is forming classifications of
patterns and building sequences. Eyes
and a nose become a face. Letters become words, words become sentences, and
sentences become novels. The cortex is
hierarchical and plastic.
The cortex divides into task specific areas based on
experience and these are arranged hierarchically, that is in order. The senses send special and temporal patterns
to the brain. In addition to the 5
senses we have proprioception and vestibular senses. Visual patterns go from the retina to V1
where horizontal lines are separated from vertical lines; v1 is the size of a
passport. Patterns are then sent to v2,
which might be letters to v3 and v4. There are auditory areas a1, a2 etc. Each
region learns sequence names and passes the name to the next level. The brain seeing partial patterns searches
memory for similar patterns it can name.
If it hears some notes it looks for the name of the song and then
anticipates the next notes before they come. The neuron for the expected note fires before
you hear the note. If the next note is
expected that level is quiet but if an unexpected note occurs it sends a
message to the higher level to make sense of.
The input changes from individual patterns to groups of
patterns i.e. a sequence of letters at a lower level becomes a sequence of words
with learning these groups move down the hierarchy a young brain takes longer because the
groups are higher a young brain has not
yet formed the complex sequences at the top,
The more you know the less you remember. You only remember
what is new. That is what makes it to the hippocampus
Brains are pattern machines. They receive patterns that they
have seen in the past. All knowledge of
the world is a model based on patterns.
The brain wants to learn sequences that recur. To the brain all of the senses are just
inputs of patterns. The brain creates a
model of its world by combining all the inputs. When a child picks up a toy it looks at it
from all different angles. He hears the
noises it makes. It smells it. It creates a name for it. The brain tends to break things into
categories. The brain puts thing in categories so we can remember things. Each color goes in a different bucket. It is fascinating that different cultures
create different boundaries between the buckets. For example different languages draw
different boundaries between sounds. This creates problems Finns don’t distinguish
between B’s and P’s. They put them in
the same bucket. A Finn can’t
distinguish between a bear and a pear. We
don’t see similarities of things on other side of the boundaries.
If the brain can predict what sequence comes next it forms a
persistent representation (memory). These are not pictures but invariant representations
of relationships of patterns. For
example, any set of eyes and a nose and mouth are a face. A song is the relation of notes. That is why we recognize it in any key. Abstract and concrete objects are treated the
same. Predictability is the definition of reality. The world has a nested structure and so does
your cortex. Your brain is always making
predictions what we perceive is a combination of what we sense and our memory
derived predictions. All areas of the neocortex are trying to predict what
their next experience will be. Correct predictions result in
understanding. Incorrect predictions
cause confusion. This is the primary function
of neocortex does and defines what is intelligence.
Motor function within the brain works exactly the same. Before we move the brain visualizes the
movement. At a high level the brain visualizes raising
your arm. Then that message is sent to
lower levels that direct the specific muscles in proper sequence. That is why ski racers do better if the
visualize racing down the course prior to the race.
Imagination works the same.
Imagining a hippo involves the same neurons firing as seeing a hippo.
Consciousness is
synonymous with forming declarative memories.
We have memories we can express in words and memories we cannot such has
how to ride a bicycle. To our cortex, our
bodies are part of the external world.
Memory leads to predictions, which leads to more memories. This makes up our thoughts. Since the cortex cannot model the brain, to
us it feels like we have an independent mind or soul.
Dreams involve
making predictions in a safe environment.
The brain can predict and rehearse what would happen if a tiger chases
you without the danger. There is an experiment where they monitor brain
activity of a rat going through a maze.
Then they monitor its dreams and see the same pattern. It’s reliving the maze.
Today’s threats seem more benign like missing class or
loosing your keys. We dream through all sleep levels but our nightmares occur
during REM sleep. It is during that
level that the limbic system is activated.
Dreams during the other levels of sleep are more peaceful.
http://en.wikibooks.org/wiki/Relationships/The_Evolution_of_the_Human_Brain
Language – how we
outsmart the plants. It facilitates winning the prisoners dilemma.
Our brains connect differently than chimpanzee brains. We have a front and back half of our cortex. Front brain high level planning, thought, and
motor function. Our neocortex took over
motor control from the reptile brain and even cerebellum. It turns out people are a little clumsy but
move ok without a cerebellum.
Language started 50,000 years ago and was followed by a
burst of technological activity. Language
is pure analogy. It lets us take
patterns we learn and pass them on to our children. We create invariant memories or stereotypes, and
then make predictions of future events.
We apply the invariant memories to new situations. A child hears 3 million words before figuring
out that words have meaning. In infancy
the baby brain responds to whatever it is exposed to. However, later in childhood the brain
becomes more selective about what learning it will accept.
All languages bucket sounds into buckets of meaning. All languages have embedded clauses,
infinite generativity, displacement, (can talk about past future) and
displacement of emotion. They have an arbitrary
relation between the signal and the message.
There is metacommunication, which is that people can talk about
language. Every language uses motherese,
which is when mothers talk in a high voice to their young. This is about cognition. Deaf babies babble in sign language. When you sign to a deaf person their auditory
system activates.
There are accents in ASL .
Language is
lateralized in 90% of people in the left-brain.
Language has procity which is what you do with your face when you talk. Procity
is located in the right hemisphere and is where sarcasm is expressed. This lateralization of functions saves on
the need for axons. Broca’s area on the
bottom of the motor strip of the brain is responsible for expressing
words. People who have a stroke damaging
that area have aphasia and can’t speak, but they understand speech.
A stroke in nearby Wernicke’s area is more devastating in
that understanding is lost. People with
this tend to babble a meaningless word salad and they can’t understand speech. Wernicke’s area is myelinated 3 months
before Broca’s area. It is interesting
that blind individuals make the same hand gestures as seeing people. There are connections between language and
the limbic system and so our voices can express emotion. We are wired to pick up our languages from
our peer group, which is why we wind up with the accent of our community, not
our peers.
It has been determined that our capacity for thought is
constrained by our language.
Again this is because of the way the brain is taught to set
up its buckets.
For example some tribes count one two and then go to many. They have no need for specific high
numbers. These are not stupid people and
they are able to name and keep track of thousands of different plants. However if tested in just adding higher
numbers they have great difficulty. This
is called the Sapir-Whorf hypothesis,
which holds that the structure of a language affects the way in which its
speakers conceptualize their world.
In learning language at 15 months a
child can say a combination of words that it has never heard Kids are able to generalize the rules of
language. Kids generate more than they
have heard. A kid can learn any language
in the first few months. You quickly loose
this ability. This is due to the sound buckets
you create. At 6 months of age kids know
vowels and by 9 months babbling starts.
Adults teaching children language is a new invention, which is unique to
the western world. In other parts of the
world kids just pick up language. It is not clear if teaching children
language works. When Learning a
language after age 6 the speech patterns are stored in the periphery of Broca’s
and Wernicke’s areas of the brain. New
languages are always invented by kids and have lateral and downward transfer.
Adults do not develop new
languages. An example is Nicaragua the kids generated
their own sign language.
Other animals have semanticity. - Monkeys
can say there is something scary on the ground or something scary in the air
informing another monkey where to hide.
Chickens can do this too and squirrels
have demonstrated an early theory of mind.
They will give alarm depending on who is around. Humans and apes are good at lying. Dogs cant. Their limbic system gives them
away. Wagging the tail is to spread its
pheromones.
5000 years ago language was used to create a model of the
world based on religion.
For all of us,
culture shapes our world model.
Culture
teaches us stereotypes, which the brain can easily accept since that are how it
works.
Language leads groups to adopt
paradigms,
which are hard to change.
Genetic traits that in one setting have a bad outcome in
another setting can be beneficial.
For
example Tay Sachs trait protects against TB and cystic fibrosis
trait protects against cholera.
In the 1970s in Europe a study was done of family members of
people with schizophrenia. They found
that family some members of schizophrenics had schizotypalism. These are people who have loose associations.
They have a social withdrawal and tend to get jobs as lighthouse keepers. They do Metamagical thinking. They are into science fiction and
fantasy. They have a concrete level of
interpretation of religion. For them, 7
day creation is not a metaphor.
They can become Shaman, medicine men and anthropologist study them.
They have a tendency toward increased dopamine tone. Under the right circumstances they can start
a religion and if circumstances are wrong they start cults
In evolutionary terms being religious has advantages. Religion is about social community and good
works. People who are religious are
healthier and have less depression.
Religion includes the carrying out of rituals. We fall into obsessive rituals during times of
anxiety and religion can help with that. After development of language, man
developed narratives. Religion enabled
the formation of large groups. People
were encouraged to be fruitful and multiply.
There is a biological basis for this.
It was only 500 years ago that man using a process of
creating a model, making predictions and then testing observations against it,
a process not unlike that of the brain, along with language communication developed the scientific process. With the addition of networks and bottom up wisdom of crowds processing with some investment progress should continue to accelerate.
