The Adolescent Brain
Lecture notes
LECTURE 1: A neuroscientific perspective on adolescent development
Goal:
• To explain adolescent development from a neuroscientific perspective, bridging neural and
social-emotional and cognitive development
• To use neuroscientific theories to explain adolescent behaviour
• To critically evaluate experimental designs based on knowledge gained on neuroscience
research methods
Neuron (= brain cell):
- Information processing / transmission takes place
- Humans have +- 100 billion neurons
- Axon = extends from cell body; nerve fiber that conducts
electrical impulses
- Dendrite = branched projections of a neuron that receives
electrical impulses
- Myelin = fatty / insulating substance surrounding axons and
optimizing transmission
Gray matter:
- consists of neuronal cell bodies
- surface of cerebral cortex and cerebellum and in subcortical
structures (e.g., amygdala, nucleus accumbens, thalamus,
hypothalamus, putamen, etc)
White matter:
- Bundles of myelinated nerve cells (axons) connecting gray matter
areas of the brain.
- The part that connects the cell bodies
- Carry nerve impulses
- Part of the fatty substance
Questions- answers
11yo has more brain cells than an adult.
Q: With age there are changes in brain function but not changes in brain structure. → false
Q: What's the global pattern of structural brain development? From back to front
Q: What happens with gray matter along adolescence? It
, Brain development starts before birth and its quite developed at
birth. By the age of 8 the size of the brain is about 80-90% of an
adult size. However, in turn its functions are not developed yet.
Across ages we see that there are increasingly more connections that
are being formed between brain cells (neurons). E.g in the first Two
years after birth there are increasingly more connections between
cells (pic down left). Increase in connections is the part that forms
the white matter, so whithe matter keeps increasing with
development. There is also an increase in myelination of the cortex.
Our increase in efficacy is connected to more connections and better
strength between brain cells.
From 4 to 20 years of age the amount of white matter increases with age. After some point in late
adulthood, white matter also starts to decrease.
,Gray matter is a bit different than white matter. It peaks much earlier (in childhood) and after
that peak, across late childhood and adolescence, it decreases. Colored figures show that in
general there are decreasing levels of grey matter across adolescence.
Non-linear decrease of GM until young adulthood happens because of:
1. Synaptogenesis: slight increase of GW because of increase in synapses at the beginning
2. Pruning: decreases is because of elimination of excess synapses
*differential trajectories across brain regions - this trajectory occurs at different times at different
brain regions
You can see that 5yo already have less GM in the occipital lobe, because this part of the brain is
already well developed - they can already see really well. So in this case GM is an indicator of
developed areas. Brain development lasts much longer than we initially thought.
, MRI
Q: Functional magnetic resonance imaging is based on which signals? BOLD - blood oxygen
level dependant.
With MRI we can take pictures of the brain, how it looks. Whereas with fMRI, indicate brain
regions that are active at the time. When we want to assess fMRI we usually show participants
images or videos so we can see brain activity.
fMRI
• It's based on blood that flows to the brain regions that are being active. When you’re busy
with a task → you need to use certain part of the brain → that part uses more oxygen
• Blood brings the oxygen to the brain parts and this results in a change in the amount of red
blood cells in the brain region being used. Red blood cells have magnetic properties and the
magnet in fMRI can assess which parts of the brain receive more blood.
• Measurements of increased blood flow
• (= more oxygen = more activity): BOLD-effect (Blood Oxygenation Level Dependent)
• Changing hemoglobin in red blood cells; magnetic properties of hemoglobin is measurable
Q: What are the advantages of fMRI compared to EEG? Participants do not need to wash their
hair after
Lecture notes
LECTURE 1: A neuroscientific perspective on adolescent development
Goal:
• To explain adolescent development from a neuroscientific perspective, bridging neural and
social-emotional and cognitive development
• To use neuroscientific theories to explain adolescent behaviour
• To critically evaluate experimental designs based on knowledge gained on neuroscience
research methods
Neuron (= brain cell):
- Information processing / transmission takes place
- Humans have +- 100 billion neurons
- Axon = extends from cell body; nerve fiber that conducts
electrical impulses
- Dendrite = branched projections of a neuron that receives
electrical impulses
- Myelin = fatty / insulating substance surrounding axons and
optimizing transmission
Gray matter:
- consists of neuronal cell bodies
- surface of cerebral cortex and cerebellum and in subcortical
structures (e.g., amygdala, nucleus accumbens, thalamus,
hypothalamus, putamen, etc)
White matter:
- Bundles of myelinated nerve cells (axons) connecting gray matter
areas of the brain.
- The part that connects the cell bodies
- Carry nerve impulses
- Part of the fatty substance
Questions- answers
11yo has more brain cells than an adult.
Q: With age there are changes in brain function but not changes in brain structure. → false
Q: What's the global pattern of structural brain development? From back to front
Q: What happens with gray matter along adolescence? It
, Brain development starts before birth and its quite developed at
birth. By the age of 8 the size of the brain is about 80-90% of an
adult size. However, in turn its functions are not developed yet.
Across ages we see that there are increasingly more connections that
are being formed between brain cells (neurons). E.g in the first Two
years after birth there are increasingly more connections between
cells (pic down left). Increase in connections is the part that forms
the white matter, so whithe matter keeps increasing with
development. There is also an increase in myelination of the cortex.
Our increase in efficacy is connected to more connections and better
strength between brain cells.
From 4 to 20 years of age the amount of white matter increases with age. After some point in late
adulthood, white matter also starts to decrease.
,Gray matter is a bit different than white matter. It peaks much earlier (in childhood) and after
that peak, across late childhood and adolescence, it decreases. Colored figures show that in
general there are decreasing levels of grey matter across adolescence.
Non-linear decrease of GM until young adulthood happens because of:
1. Synaptogenesis: slight increase of GW because of increase in synapses at the beginning
2. Pruning: decreases is because of elimination of excess synapses
*differential trajectories across brain regions - this trajectory occurs at different times at different
brain regions
You can see that 5yo already have less GM in the occipital lobe, because this part of the brain is
already well developed - they can already see really well. So in this case GM is an indicator of
developed areas. Brain development lasts much longer than we initially thought.
, MRI
Q: Functional magnetic resonance imaging is based on which signals? BOLD - blood oxygen
level dependant.
With MRI we can take pictures of the brain, how it looks. Whereas with fMRI, indicate brain
regions that are active at the time. When we want to assess fMRI we usually show participants
images or videos so we can see brain activity.
fMRI
• It's based on blood that flows to the brain regions that are being active. When you’re busy
with a task → you need to use certain part of the brain → that part uses more oxygen
• Blood brings the oxygen to the brain parts and this results in a change in the amount of red
blood cells in the brain region being used. Red blood cells have magnetic properties and the
magnet in fMRI can assess which parts of the brain receive more blood.
• Measurements of increased blood flow
• (= more oxygen = more activity): BOLD-effect (Blood Oxygenation Level Dependent)
• Changing hemoglobin in red blood cells; magnetic properties of hemoglobin is measurable
Q: What are the advantages of fMRI compared to EEG? Participants do not need to wash their
hair after
