Neurobiology summary
1
,Lecture 1&2: Introduction to the brain
History of brain research
- Prehistory elders: knew that the brain was essential for life, they performed skull/brain
surgeries (not only post mortem to perhaps give evil spirits an escape route)
- Ancient Egypt: thought that the heart contains the soul and the brain
- Ancient Greece: Hippocrates believed that the brain was involved in sensation and
the seat of intelligence
- Roman Empire: Van Galen M.D. believed that the cerebrum receives sensory input
and the cerebellum is responsible for the motoric coordination, and that the
regulation of coordination of movements by displacement of fluid through vesicles in
the brain and hollow nerves
- The Renaissance up to the 19th century: Vesalius and Descartes believed in the
Ventricular theory; that sense information went from the eye nerves to the ventricles to
the mind and that motor control was achieved by the pineal gland
• The ventricular system in the brain is responsible for protecting and washing
away toxic waste by cerebral spinal fluid. Sleep is very important for brain
clearance. The brain has four ventricles; the 1e and 2e ventricle are the
lateral ventricles and the 3e and 4e ventricle are bigger.
• The brain makes new cerebral spinal fluid by the Choroid plexus cells
- 17-18th century: learned about white matter (axons) and grey matter (cell body and
dendrites). They learned that the brain consists a lot of connections (white matter)
- 19th century: knew the basic divisions of the nervous system: the central an peripheral
nervous system. The nerves guide weak but quick
electrical signals to communicate.
Phrenology: The structure of the head is correlated with certain personality traits
(reliability, intelligence.
Broca concluded that certain regions in the cerebrum are responsible for certain
functions, for example speaking
2
,Brain imaging -scanning methods
- CT scan: more clearly than MRI scan (white boundary) You can look for activity lose, for
- MRI scan (grey image) → Takes much longer example resulting from a stroke
- PET scan: using a tracer for looking at the brain activity Functional brain
- fMRI scan: giving the patient a task and looking at the local brain activity imaging
Psychopaths have lose activity in the prefrontal cortex, this region is responsible for normal
behavior. They have different activity patterns in inhibiting areas of the brain.
Phineas Gage survived despite losing his prefrontal cortex, and really became a different
person. Lobotomy is a therapy against unwanted behavior (e.g. sexual preferences) by
causing disruption of the prefrontal cortex. This therapy could change the personality
The brain
The increase in folds in the brain gives the brain more surface area, increasing more room for
more neurons
Sagittal plane: from nose to
back of the head (good way
to see the lobes and the
ventricles)
Coronal (transverse cut) plane:
good way to distinguish the
white and grey matter
(connections), from ear to ear
3
, Brain analyses
Nissl staining: staining the brain tissue to distinguish the grey from the white matter (pinkish)
Golgi staining: see all the individual dendrites (yellowish) → is still being used
Cajal was decisive; dendrites and axons belong to one soma/neuron and the battle
between Nissl and Golgi was ended. Cajal and Golgi together received the Nobel
prize but remained rivals. Eventually Cajal was right: Communication by contact, not
by continuity
Different types of cells found in the brain
Neurons that receive information from our sensory
organs an transmit this input to the central nervous
system are called afferent neurons. Neurons that
send impulses from the central nervous system to
your limbs ad organs are called efferent neurons
The neuron can have more than one dendrites but
only one axon (axon can split tho). Multipolar
neurons can be divided into stellate cells (round)
and pyramidal cells (more long)
The cortex consists of multiple layers of neurons, this
is discovered by the use of tracing studies, and this
can be established by two methods:
- Retrograde transport: tracing back over
the axonal bundles to the neurons that provided input to this region
- Anterograde transport: to see to which place the neurons provide information to
(using viruses)
Memory loss can be also anterograde (short time ago) or retrograde (long time ago)
EM studies provided final proof that a single neuron contains dendrites, spines, soma, axon
terminal and spines
Neurites are the dendrites plus the axons
Dendritic spines variable in size and shape, and are easy to change into another
shape/size/amount → change in how the information is being processed
4
1
,Lecture 1&2: Introduction to the brain
History of brain research
- Prehistory elders: knew that the brain was essential for life, they performed skull/brain
surgeries (not only post mortem to perhaps give evil spirits an escape route)
- Ancient Egypt: thought that the heart contains the soul and the brain
- Ancient Greece: Hippocrates believed that the brain was involved in sensation and
the seat of intelligence
- Roman Empire: Van Galen M.D. believed that the cerebrum receives sensory input
and the cerebellum is responsible for the motoric coordination, and that the
regulation of coordination of movements by displacement of fluid through vesicles in
the brain and hollow nerves
- The Renaissance up to the 19th century: Vesalius and Descartes believed in the
Ventricular theory; that sense information went from the eye nerves to the ventricles to
the mind and that motor control was achieved by the pineal gland
• The ventricular system in the brain is responsible for protecting and washing
away toxic waste by cerebral spinal fluid. Sleep is very important for brain
clearance. The brain has four ventricles; the 1e and 2e ventricle are the
lateral ventricles and the 3e and 4e ventricle are bigger.
• The brain makes new cerebral spinal fluid by the Choroid plexus cells
- 17-18th century: learned about white matter (axons) and grey matter (cell body and
dendrites). They learned that the brain consists a lot of connections (white matter)
- 19th century: knew the basic divisions of the nervous system: the central an peripheral
nervous system. The nerves guide weak but quick
electrical signals to communicate.
Phrenology: The structure of the head is correlated with certain personality traits
(reliability, intelligence.
Broca concluded that certain regions in the cerebrum are responsible for certain
functions, for example speaking
2
,Brain imaging -scanning methods
- CT scan: more clearly than MRI scan (white boundary) You can look for activity lose, for
- MRI scan (grey image) → Takes much longer example resulting from a stroke
- PET scan: using a tracer for looking at the brain activity Functional brain
- fMRI scan: giving the patient a task and looking at the local brain activity imaging
Psychopaths have lose activity in the prefrontal cortex, this region is responsible for normal
behavior. They have different activity patterns in inhibiting areas of the brain.
Phineas Gage survived despite losing his prefrontal cortex, and really became a different
person. Lobotomy is a therapy against unwanted behavior (e.g. sexual preferences) by
causing disruption of the prefrontal cortex. This therapy could change the personality
The brain
The increase in folds in the brain gives the brain more surface area, increasing more room for
more neurons
Sagittal plane: from nose to
back of the head (good way
to see the lobes and the
ventricles)
Coronal (transverse cut) plane:
good way to distinguish the
white and grey matter
(connections), from ear to ear
3
, Brain analyses
Nissl staining: staining the brain tissue to distinguish the grey from the white matter (pinkish)
Golgi staining: see all the individual dendrites (yellowish) → is still being used
Cajal was decisive; dendrites and axons belong to one soma/neuron and the battle
between Nissl and Golgi was ended. Cajal and Golgi together received the Nobel
prize but remained rivals. Eventually Cajal was right: Communication by contact, not
by continuity
Different types of cells found in the brain
Neurons that receive information from our sensory
organs an transmit this input to the central nervous
system are called afferent neurons. Neurons that
send impulses from the central nervous system to
your limbs ad organs are called efferent neurons
The neuron can have more than one dendrites but
only one axon (axon can split tho). Multipolar
neurons can be divided into stellate cells (round)
and pyramidal cells (more long)
The cortex consists of multiple layers of neurons, this
is discovered by the use of tracing studies, and this
can be established by two methods:
- Retrograde transport: tracing back over
the axonal bundles to the neurons that provided input to this region
- Anterograde transport: to see to which place the neurons provide information to
(using viruses)
Memory loss can be also anterograde (short time ago) or retrograde (long time ago)
EM studies provided final proof that a single neuron contains dendrites, spines, soma, axon
terminal and spines
Neurites are the dendrites plus the axons
Dendritic spines variable in size and shape, and are easy to change into another
shape/size/amount → change in how the information is being processed
4
