Summary
Summary Lectures + Practice questions
- Course
- Institution
Lectures as needed for the exam of Medical Neuroscience and Neuroanatomy, including practise questions based on the lectures.
[Show more]
2 reviews
By: camsookha • 4 year ago
By: fatimasacirovic • 4 year ago
Seller
FollowCatoVU
Reviews received
Content preview
This is a summary of the lectures of the course “Medical Neuroscience andNeuranatomy”. At the end of this document, you will find a practise exam, with 28
multiple choice questions and open ended questions, and their answers. Good luck with
studying!
,Content
A. Lecture 1.............................................................................................................................................3
B. Lecture 2.............................................................................................................................................5
C. Lecture 3.............................................................................................................................................7
D. Lecture 4..........................................................................................................................................10
E. Lecture 5...........................................................................................................................................11
F. Lecture 6...........................................................................................................................................13
G. Lecture 7..........................................................................................................................................15
H. Lecture 8..........................................................................................................................................16
I. Lecture 9............................................................................................................................................18
K. Lecture 10.........................................................................................................................................23
L. Lecture 13.........................................................................................................................................25
M. Lecture 13.......................................................................................................................................27
N. Lecture 14........................................................................................................................................28
O. Lecture 15........................................................................................................................................30
P. Lecture 16.........................................................................................................................................32
Q. Lecture 17........................................................................................................................................34
R. Lecture 18.........................................................................................................................................35
S. Lecture 19.........................................................................................................................................36
T. Lecture 20.........................................................................................................................................38
U. Lecture 16........................................................................................................................................40
V. Lecture 17.........................................................................................................................................41
W. Extra clinical cases...........................................................................................................................43
X. Exam questions.................................................................................................................................44
Y. Answers............................................................................................................................................49
, A. Lecture 1
Strokes in the motor system
In the clinical system, there is a difference between a paralysis and a paresis. In the case
of a paralysis, no function at all will be observed. In the case of a paresis, some function
will be observed.
Other terms often used intermingled are a stroke and a CVA. A CVA stands for
cerebrovascular accident and is the same as a stroke: so, a haemorrhage in the brain.
This bleeding usually happens in the middle cerebral artery (MCA). The MCA is
especially vulnerable for strokes. The reason why the MCA is more vulnerable, is that it is
harder for an emboli (so, a blood clot) to enter the posterior (PCA)or anterior cerebral
artery (ACA) than it is to enter the MCA. After a stroke, oedema often occurs, which
causes extra pressure in the brain.
In case of a stroke in the MCA, the pyramidal tracts are often damaged. The pyramidal
tract consists of the motor tracts descending from the cortex to the spine. A synonym
often used for these sort of tracts is the corticospinal tract.
The primary motor area is one of the cortical areas and can be found a bit anterior (so,
located before) to the central sulcus. In case of a stroke of the MCA, the motor system is
often damaged, which causes a spasm in the anti-gravity muscles. The pyramidal system
is involved in fine motor activity, while the extrapyramidal system is involved in crude
motor activity. Next, the extrapyramidal system is responsible in posture and muscle
tone. If a spasm occurs in the anti-gravity muscles, there will be a hypertonia in the
muscles of the stretchers of the leg. The MCA does not affect the part of the homunculus
that is responsible for the leg and leg function will therefore still be there. Yet, the arm
will have lost function, because the MCA does affect the part of the homunculus that is
responsible for the arms.
Clinical case
In the case of a patient that has a hemiparesis, but no sensory loss, there are different
possible causes. A hemiparesis means that the paresis affects half of the body. In this
specific case, only the lower part of the face is affected.
The nerve endings in the peripheral system of both the sensory and motor neurons, are
very close together. Therefore, chances that a peripheral problem is the cause of a
hemiparesis without sensory loss, are very slight. Next, the parietal lobe will probably not
be damaged as well. One of the main functions of this lobe is somatosensory
functions, so all bodily – and sensory – sensations. Since in this case no sensory loss is
experienced, the parietal lobe is probably spared.
If the medulla or spinal cord would be damaged, than the whole face would be spared.
Next, it cannot be a muscle or peripheral problem, since that would mean that the entire
face would be affected. Lastly, the thalamus cannot be the problem, because this is a
sensory processing area and it is therefore not possible that there would be no sensory
loss.
The only options available to be damaged are the corticospinal and corticobulbar tract.
Nervous system
In the body, a distinction can be made in the peripheral nervous system (PNS) and
the central nervous system (CNS). The CNS consists of the brain and the spinal cord,
while all the other nerve bundles fall under the PNS. Even nerves such as the cranial
nerves fall under the PNS.
In the brain, a distinction can be made in grey matter or white matter. The white
matter contains all fiber tracts and the grey matter are all other structures and can be
found in both cortical and subcortical areas. In the cortex, white matter can be found as
well, even though the subcortical areas contains more white matter. Both parts of the
, brain need white matter in order to ensure communication. If a lesion occurs in the
subcortical areas, cortical functions will be affected as well. Cortical functions are
functions such as executive functions (planning, inhibition), language, spatial information
processing, etc.
There are different kinds of white matter fibers, which are listed below:
A tractus, a bundle of fibers. An example of this is the corticospinal tract or the
pyramidal tract. In the corticospinal tract, an upper motor neuron and a lower
motor neuron can be found. The upper motor is part of the CNS and the lower
motor neuron is part of the PNS;
Vesicles, a bundle of small fibers;
Funiculus, a bundle of vesicles, either one or multiple. One funiculus is found in
the pain system, for example the dorsolateral funiculus, which is responsible
for pain signals;
Lemnicus, a bundle of secondary sensory fibers. These fibers are secondary, so
information such as position of the limbs, which is called proprioception. An
important lemniuscus is the dorsal column. The dorsal column is divided into the
fasciculus gracilis (lower body) and the fasciculus cuneatus (upper body);
Capsula, descending and ascending fibers. An ascending fiber leads up, from
the nerve to a place higher on the spinal cord and a descending fiber leads down
to a fiber. A painful stimulus ascends, goes up to the brain, and an ascending
signal will supress this painful stimulus.
An example of a higher order cognitive pathway is the frontostriatal pathway. This
tract starts at the basal ganglia, in the striatum. The striatum consists of the putamen
and the caudate nucleus. The pathway between the prefrontal cortex (a cortical area)
and the striatum (a subcortical area) is responsible for executive functions as planning
and inhibition. Patients with Parkinson’s disease have a lesion in the basal ganglia.
They suffer from a defect in the neurotransmitter dopamine, which is produced in the
substantia nigra. The dopamine is sent to the basal ganglia. If this area is affected, then
frontostriatal pathway will not function properly.
Distinctive areas in the nervous system
The nervous system consists of different areas. The lowest part is the spinal cord,
followed by, from posterior to anterior, the myelencephalon (medulla), and the
metencephalon (pons and cerebellum), which together form the hindbrain or the
rhombencephalon. Next is the mesencephalon or the midbrain, which contains the
tegmentum and tectum and the cerebral peduncles. Lastly, there is the prosencephalon
or the forebrain, which consists of the diencephalon (thalamus, hypothalamus, and
epithalamus) and then the most anterior part of the brain, the telencephalon (cerebral
hemispheres, the basal ganglia, basal forebrain, the subcortical white matter, and the
cerebral cortex).
During the embryonic stages, the neural tube will arise and form the brain. The
structures can be viewed from high to low, where the telencephalon forms the outside of
the brain and the diencephalon forms the inside of the brain. Next, the rhombencephalon
forms the brainstem.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller CatoVU. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $7.02. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
57413 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now