Aantekeningen hoorcolleges Neuropsychologie*
* De hoorcolleges van dit vak zijn in het Engels gegeven. Ook het tentamen zal in het Engels zijn.
Vandaar dat deze aantekeningen ook in het Engels zijn. De grammatica is niet altijd even correct.. :)
Af en toe een Nederlandse vertaling achter het woord tussen haakjes.
Topic 1 – Evolution & Function of the nervous system
Evolution & historical perspectives on mind & brain
The brain is so important, since it’s primary function is to produce behavior. To do so, it must:
• receive information about the world (through our senses: touch, smell…)
• integrate information to create a sensory reality (different for everyone)
• make a constant stream of predictions about what to expect (which leads to save, smooth
and automatic behavior)
• produce commands to control the movement of muscles
(that’s how you observe a behavior)
The make up of the nervous system (like the somatic nervous system)
altogether allows the brain to do so.
What is Behavior?
• Relatively Fixed Behaviors (innate behavior)
o Dependent on heredity: when they are born
• Relatively Flexible Behaviors
o Dependent on learning
• Complexity of behavior varies considerably in different species
depending on complexity of nervous system (and the brain)
o The more complex the nervous system and the brain is,
the more complex behavior an animal can display
Philosophy of brain and behavior:
• Aristotle: Mentalism (this is where it started)
o An explanation of behavior as a function of the nonmaterial mind: there’s something
that’s not in our body (can’t see or touch), that influences our mind.
o Ancient Greece: Aristotle
▪ Psyche or soul: Synonym for mind; an entity once proposed to be the source
of human behavior, that lives after death (still there when you die)
• Descartes: Dualism (how can our body be influenced by something that’s not there)
o Both a nonmaterial mind and the material body contribute to behavior
o Mind directs rational behavior
o Body and brain direct all other behavior via mechanical and physical principles
▪ Examples: sensation, movement, and digestion
o Mind is connected to the body through the pineal gland of the brain: that’s the part
where the nonmaterial mind could influence our behavior
▪ Some simple behavior was controlled by the body, no mind needed
, o Mind–Body Problem
▪ Difficult / impossible to explain a nonmaterial mind in command of a
material body: how do these to entity’s connect
• Darwin: Materialism (what we still believe now)
o Behavior can be explained as a function of the nervous system without considering
the mind as a separate substance
▪ It doesn’t say that there’s nothing like thoughts in our head or that we can’t
have emotions. It just says that we can explain that by studying the brain.
o Related to evolutionary theory of Charles Darwin
▪ We can understand the human brain by studying the brain of animals that
are older in evolution or more simple. That’s why this is related to 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!!
▪ If you’re better able to cope whit the environment, the changes that you will
pass on your genes are higher. Because this happens over a long time,
species developed.
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 systems:
All the animals you see here have nervous systems in some way. It starts from very simple to more
complex. There are nervous cells but there’s no brain with the first animals. Some parts of the body
control other muscles. In the next level there’s the ganglia: more complex neural structures. Then
there’s the brain. You just have to know that it’s likely that us humans started as a basic nervous
system. Every species adapted different to different environments. That’s how neuro systems and
the brain became more and more complex over time. There are neuro systems in the sea anemone
that are still related to humans.
,The higher your brain weight compared to your body, the more complex behavior you can show.
There’s a relation between how complex your brain is and how complex your behavior is.
Neuroplasticity - the brain is plastic: the brain is always developing as a function of how you interact
with the environment. The brain causes your behavior and your behavior also causes your brain.
• 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 and in adaptations of brain structure
following injury
How the brain adapts to the environment is related to the epigenetics:
• Study of differences in gene expression related to environment and experience
• Epigenetic factors do not change your genes, but they do influence how your genes operate
• When you’re born all your genes are there, but not everything in your DNA comes to
expression during live. Not everything has an impact on your behavior.
▪ What will have an impact or not, depends on your environment.
• Epigenetic changes can persist throughout a lifetime, and the cumulative effects can make
dramatic differences in how your genes work and how likely a spieces is to pass on its genes
→ evolution
Plastic patterns of neural organization: Phenotypic Plasticity
An individual’s genotype (genetic makeup) interacts with the environment to elicit a specific
phenotype from a large repertoire of possibilities. There’s a picture of two mice which are
exactly the same, but one became much thicker and blonder by the food they gave him.
Studying brain and behavior in modern humans: the brain – and especially the cortex – is highly
flexible. That means that humans can live VERY different life styles in VERY different environments,
with equal skill and success. That also means that individual differences in brain organization are
huge! The average brain does not exist!
, Anatomical & functional divisions of the nervous system
The somatic nervous system is about the information coming from your senses (like your eyes) to
your brain and from your brain back to your muscles. Autonomic nervous system is about heart rate,
respiration, digestion. In the 6th edition they added the enteric nervous system, which controls the
gut. The bacteria in our gut have a big influence on our brain. That’s probably why what you eat can
effect your mood. We will start whit the brain (central nervous system).
Overview of the structure of the brain:
• Forebrain: Major structure of the brain, consisting of two almost identical hemispheres (left
and right). Prominent in mammals and birds, responsible for most higher order conscious
behaviors (cognition, executive functions).
o Left and right hemispheres have different functions sometimes.
o The forebrain is what makes the hunman behavior very complex.
• Cerebellum: “Little brain”
o Involved in the coordination of motor and
cognitive processes.
o It has as many neurons as the rest of
the brain, so many important.
• Brainstem: Central structures of the
brain, including the hindbrain,
midbrain, thalamus & hypothalamus.
Source of behavior in simpler animals,
responsible for most of our unconscious
behaviors.
• Spinal cord: Consists of nerves that
carry incoming and outgoing messages
between the brain and the rest of the
body including reflexes.
o Goes down to your back, still part of the nervous system
Next, you see a overview from all you need to know about the centrum nervous system. You can use
it as a check box: where is this brain structure in the hierarchy of the brain.
