CBWL 1
Evolution & function of the nervous system
01-09-2023
Why is the brain so important?
- The primary function is to produce behavior. To do so, it must:
o Receive information about the world
o
o Integrate information to create a sensory reality
o Make a constant stream of predictions about what to expect (important because: only if
you can make predictions, you can adapt your behavior)
o Produce commands to control the movement of muscles
- The make up of the nervous system altogether allows the brain to do so
Where does evidence of the brain comes from
- Evolution of the brain in diverse animal species
- How the brain is related to behavior in typical people
- How the brain changes in people with brain damage or other brain dysfunction
What is behavior?
There are different types of behavior:
- Relatively fixed behaviors: dependent on heredity (erfelijkheid)
➔ For example: a bird is able to open the cones as soon as it’s born
- Relatively flexible behavior: dependent on learning
➔ For example; a rat must learn how to eat pine cones
Complexity of behavior varies considerably in different species depending on complexity of nervous
system (the more complex the nerve system → the more complex the brain → the more complex
behavior). Animals with smaller, simpler nervous systems show a narrow range of behavior that depend
on heredity an animals with a more complex nervous system have more behavior depending on learning.
Philosophy of brain and behavior
1. Mentalism
o An explanation of behavior as a function of the nonmaterial mind
o Nonmaterial mind: there is something (a psyche or soul) that is not in our body (we
can’t see or touch), that influences our mind. It wasn’t observable and it would still be
there if someone would die. (Ancient Greece: Aristotle)
2. Dualism
o Both a nonmaterial mind and the material body contribute to behavior
o Mind directs rational behavior. The body and brain direct all other behavior via
mechanical and physical principles (sensation, movement and digestion)
o Mind is connected to the body through the pineal gland (pijnappelklier) of the brain
o Some simple behavior was controlled by the body: there was no nonmaterial mind
needed for that.
o Mind-body problem: difficult/ impossible to explain a nonmaterial mind in command
of a material body (hard to explain how something that is nonmaterial can command
something that is material?)
3. Materialism
o Behavior can be explained as a function of the nervous system without considering the
mind as a separate substance
o Related to evolutionary theory of Charles Darwin
o Darwin’s Concept of Natural Selection: differential success in the reproduction (i.e.,
passing on your genes) of different characteristics / behavior (phenotypes) results from
the interaction of organisms with their environment (als je je beter hebt aangepast aan
de omgeving, zal je een grotere kans hebben te overleven en voor nageslacht te zorgen)
1
, o Traits/ behavior that increase reproductive success and chances of survival will be
passed on to offspring
o Competition is a key concept
Evolution of animals having nervous system
From a simple to a more
complex nerve system
The human brain has (relatively)
the largest size to our body weight.
The higher the ratio between your
body weight and your brain
weight, the more complex
behavior you can show
Neuroplasticity
- The brain is plastic (your behavior can change your brain → it can adapt to the environment)
- Neural tissue has the capacity to adapt to the world by changing how its functions are organized
- Because the brain can adapt to the world, different species could develop
- Neuroplasticity is seen both in the developing brain (differences between the brains of a child
who lives in a stimulating environment and a child who lives in a poor environment) and in
adaptations of brain structure following injury
- Connections between neurons within the brain are constantly changing, due to new experiences.
Epigenetics
- How the brain can adapt to the environment is related to epigenetics
- Study of differences in gene expression related to environment and experience
2
Evolution & function of the nervous system
01-09-2023
Why is the brain so important?
- The primary function is to produce behavior. To do so, it must:
o Receive information about the world
o
o Integrate information to create a sensory reality
o Make a constant stream of predictions about what to expect (important because: only if
you can make predictions, you can adapt your behavior)
o Produce commands to control the movement of muscles
- The make up of the nervous system altogether allows the brain to do so
Where does evidence of the brain comes from
- Evolution of the brain in diverse animal species
- How the brain is related to behavior in typical people
- How the brain changes in people with brain damage or other brain dysfunction
What is behavior?
There are different types of behavior:
- Relatively fixed behaviors: dependent on heredity (erfelijkheid)
➔ For example: a bird is able to open the cones as soon as it’s born
- Relatively flexible behavior: dependent on learning
➔ For example; a rat must learn how to eat pine cones
Complexity of behavior varies considerably in different species depending on complexity of nervous
system (the more complex the nerve system → the more complex the brain → the more complex
behavior). Animals with smaller, simpler nervous systems show a narrow range of behavior that depend
on heredity an animals with a more complex nervous system have more behavior depending on learning.
Philosophy of brain and behavior
1. Mentalism
o An explanation of behavior as a function of the nonmaterial mind
o Nonmaterial mind: there is something (a psyche or soul) that is not in our body (we
can’t see or touch), that influences our mind. It wasn’t observable and it would still be
there if someone would die. (Ancient Greece: Aristotle)
2. Dualism
o Both a nonmaterial mind and the material body contribute to behavior
o Mind directs rational behavior. The body and brain direct all other behavior via
mechanical and physical principles (sensation, movement and digestion)
o Mind is connected to the body through the pineal gland (pijnappelklier) of the brain
o Some simple behavior was controlled by the body: there was no nonmaterial mind
needed for that.
o Mind-body problem: difficult/ impossible to explain a nonmaterial mind in command
of a material body (hard to explain how something that is nonmaterial can command
something that is material?)
3. Materialism
o Behavior can be explained as a function of the nervous system without considering the
mind as a separate substance
o Related to evolutionary theory of Charles Darwin
o Darwin’s Concept of Natural Selection: differential success in the reproduction (i.e.,
passing on your genes) of different characteristics / behavior (phenotypes) results from
the interaction of organisms with their environment (als je je beter hebt aangepast aan
de omgeving, zal je een grotere kans hebben te overleven en voor nageslacht te zorgen)
1
, o Traits/ behavior that increase reproductive success and chances of survival will be
passed on to offspring
o Competition is a key concept
Evolution of animals having nervous system
From a simple to a more
complex nerve system
The human brain has (relatively)
the largest size to our body weight.
The higher the ratio between your
body weight and your brain
weight, the more complex
behavior you can show
Neuroplasticity
- The brain is plastic (your behavior can change your brain → it can adapt to the environment)
- Neural tissue has the capacity to adapt to the world by changing how its functions are organized
- Because the brain can adapt to the world, different species could develop
- Neuroplasticity is seen both in the developing brain (differences between the brains of a child
who lives in a stimulating environment and a child who lives in a poor environment) and in
adaptations of brain structure following injury
- Connections between neurons within the brain are constantly changing, due to new experiences.
Epigenetics
- How the brain can adapt to the environment is related to epigenetics
- Study of differences in gene expression related to environment and experience
2
