The basal ganglia and cerebellum work together to modify movement on a minute-to-minute basis. The basal ganglia are a collection of nuclei that provide inhibitory output and help apply "brakes" to movement. The cerebellum compares intended and actual movements to coordinate them and learns motor skills; it provides excitatory output. Disturbances in either system cause movement disorders like Parkinson's and Huntington's diseases.
Functional Anatomy & physiology of the Basal nucleiRafid Rashid
Provides a good description of the functional anatomy & physiology of the basal nuclei/ basal ganglia for undergraduate medical students. It also describes disorders of the basal ganglia like parkinsonism & chorea.
This pp was created for a PBL problem based on a brief overview on the histology of the cerebral cortex, epilepsy and EEG procedure and the mechanism of action of anticonvulsants
Functional Anatomy & physiology of the Basal nucleiRafid Rashid
Provides a good description of the functional anatomy & physiology of the basal nuclei/ basal ganglia for undergraduate medical students. It also describes disorders of the basal ganglia like parkinsonism & chorea.
This pp was created for a PBL problem based on a brief overview on the histology of the cerebral cortex, epilepsy and EEG procedure and the mechanism of action of anticonvulsants
10 Tips for Making Beautiful Slideshow Presentations by www.visuali.seEdahn Small
1. Know your goal | make each slide count
2. Plan it out | in some detail
3. Avoid templates | they have the uglies
4. Choose a color scheme | 4 colors, 1 accent
5. Choose a font scheme | match tone
6. Choose a layout scheme | comprehension
7. Use images (wisely) | they’re more memorable
8. 15 words per slide | this slide had 16 words
9. Play with typography | impact, interest, hierarchy
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LECTURE 99From Neurons to the Nervous System to the Brain The .docxmanningchassidy
LECTURE 99From Neurons to the Nervous System to the Brain
The neuron's place as the primary functional unit of the nervous system was first recognized in the late 19th century by the Spanish anatomist Santiago Ramón y Cajal (1852-1934), a neuroscientist and pathologist specializing in neuroanatomy and, especially, the central nervous system.
In 1888 Ramón y Cajal published a paper about the pigeon cerebellum. In this paper, he stated that he could not find evidence for cross connections (anastomosis) between axons and dendrites and called each nervous element "an absolutely autonomous canton." This became known as the neuron doctrine, one of the central tenets of modern neurobiology.
Above is his 1899 drawing of neurons in the pigeon cerebellum.
This Lecture focuses on the chemistry of neurons, specialized cells that transmit chemical and electrical signals to facilitate communication between the brain and the body. In learning about a new field, one can get befuddled very quickly with the jargon used by experts in the field and get lost, not being able “to see the forest for the trees.” So, before each section, I give a summary of Key Points and Key Terms you will need to understand that section. At the expense of “over kill,” I have repeated earlier “points” and “terms” at subsequent points in the Lecture so that you won’t have to “backtrack” to figure out what is going on.
Neurons are specialized cells that transmit chemical and electrical signals in the brain. They are the basic building blocks of the central nervous system.
Key Points:
· Neurons are specialized cells that transmit chemical and electrical signals in the brain; they are the basic building blocks of the central nervous system.
· The primary components of the neuron are the soma (cell body), the axon (a long slender projection that conducts electrical impulses away from the cell body), dendrites (tree-like structures that receive messages from other neurons), and synapses (specialized junctions between neurons).
· Some axons are covered with myelin, a fatty material that acts as an insulator and conductor to speed up the process of communication.
· Sensory neurons are neurons responsible for converting external stimuli from the environment into corresponding internal stimuli.
· Motor neurons are neurons located in the central nervous system (CNS); they project their axons outside of the CNS to directly or indirectly control muscles.
· Interneurons act as the “middle men” between sensory and motor neurons, which convert external stimuli to internal stimuli and control muscle movement, respectively.
Key Terms:
· glial cell: Non-neuronal cells that provide structure and support to neurons.
· synapse: The junction between the terminal of a neuron and either another neuron or a muscle or gland cell, over which nerve impulses pass.
· myelin: A white, fatty material composed of lipids and lipoproteins that surrounds the axons of nerves and facilitates swift commu.
Largest part of hind brain.
Called “ silent area/Little Brain ”
Weight- 150 gms.
Cerebellar cortex is a large folded sheet, each fold is called Folium.
Connected to brain stem by 3 pairs of peduncles- Superior (Brachium conjunctiva), Middle (Brachium Pontis) & Inferior (Restiform body) peduncle.
The term basal nuclei is applied to a collection of masses of gray matter situated within each cerebral hemisphere.
They are the
corpus striatum,
amygdaloid nucleus,
claustrum.
The subthalamic nuclei, the substantia nigra, and the red nucleus are functionally closely related to the basal nuclei.
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
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Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
New Drug Discovery and Development .....NEHA GUPTA
The "New Drug Discovery and Development" process involves the identification, design, testing, and manufacturing of novel pharmaceutical compounds with the aim of introducing new and improved treatments for various medical conditions. This comprehensive endeavor encompasses various stages, including target identification, preclinical studies, clinical trials, regulatory approval, and post-market surveillance. It involves multidisciplinary collaboration among scientists, researchers, clinicians, regulatory experts, and pharmaceutical companies to bring innovative therapies to market and address unmet medical needs.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
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TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
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Basic neuroanatomy: Anatomy of the basal ganglia and the cerebellum
1. BASAL GANGLI A AND
CEREBELLUM
I NTRODUCTI ON
The basal ganglia and cerebellum are large collections of nuclei that modify movement on a
minute-to-minute basis. M otor cortex sends information to both, and both structures send
information right back to cortex via the thalamus. (Remember, to get to cortex you must go
through thalamus.) The output of the cerebellum is excitatory, while the basal ganglia are
inhibitory. The balance between these two systems allows for smooth, coordinated movement, and
a disturbance in either system will show up as movement disorders.
A. The basal ganglia:
What are the basal ganglia? The name is confusing, as generally a ganglion is a collection of cell
bodies outside the central nervous system. Blame the early anatomists. The basal ganglia are a
collection of nuclei deep to the white matter of cerebral cortex. The name includes: caudate,
putamen, nucleus accumbens, globus pallidus, substantia nigra, subthalamic nucleus, and
historically the claustrum and the amygdala. However, the claustrum and the amygdala do not
really deal with movement, nor are they interconnected with the rest of the basal ganglia, so they
have been dropped from this section. Other groupings you may hear are the striatum (caudate +
putamen + nucleus accumbens), the corpus striatum (striatum + globus pallidus), or the lenticular
nucleus (putamen + globus pallidus), but these groupings obviously get confusing very quickly, so
we will try to avoid them.
The anatomy of these structures should be a review from the "coronal and horizontal sections"
lab. Here once again are the basal ganglia as they appear when stained for myelin:
2. caudal section:
An alternate stain is the acetylcholinesterase (AChE) stain. This technique stains for the enzyme
that degrades acetylcholine (ACh), a major neurotransmitter. Areas which use ACh generally
stain darkly. Here is a section through monkey brain, stained for AChE.
3. You can see that the caudate and putamen are stained, while the globus pallidus remains fairly
pale. This emphasizes their different functions and connections. And those are...?
B. Different functions and connections:
The relationships between the nuclei of the basal ganglia are by no means completely understood.
When dealing with the brain, you may sometimes be tempted to think that everything is connected
to everything else. Take heart, some fairly simple generalizations and schematics can be drawn.
The caudate and putamen receive most of the input from cerebral cortex; in this sense they are the
doorway into the basal ganglia. There are some regional differences: for example, medial caudate
and nucleus accumbens receive their input from frontal cortex and limbic areas, and are
implicated more in thinking and schizophrenia than in moving and motion disorders. The caudate
and putamen are reciprocally interconnected with the substantia nigra, but send most of their
output to the globus pallidus (see diagram below).
The substantia nigra can be divided into two parts: the substantia nigra pars compacta (SNpc)
and the substantia nigra pars reticulata (SNpr). The SNpc receives input from the caudate and
putamen, and sends information right back. The SNpr also receives input from the caudate and
putamen, but sends it outside the basal ganglia to control head and eye movements. The SNpc is
the more famous of the two, as it produces dopamine, which is critical for normal movement. The
SNpc degenerates in Parkinson's disease, but the condition can be treated by giving oral dopamine
precursors.
The globus pallidus can also be divided into two parts: the globus pallidus externa (GPe) and the
globus pallidus interna (GPi). Both receive input from the caudate and putamen, and both are in
communication with the subthalamic nucleus. I t is the GPi, however, that sends the major
inhibitory output from the basal ganglia back to thalamus. The GPi also sends a few projections to
an area of midbrain (the PPPA), presumably to assist in postural control.
This schematic summarizes the connections of the basal ganglia as described above.
Although there are many different neurotransmitters used within the basal ganglia (principally
ACh, GABA, and dopamine), the overall effect on thalamus is inhibitory. The function of the basal
ganglia is often described in terms of a "brake hypothesis". To sit still, you must put the brakes on
all movements except those reflexes that maintain an upright posture. To move, you must apply a
4. brake to some postural reflexes, and release the brake on voluntary movement. I n such a
complicated system, it is apparent that small disturbances can throw the whole system out of
whack, often in unpredictable ways. The deficits tend to fall into one of two categories: the
presence of extraneous unwanted movements or an absence or difficulty with intended
movements.
C. Lesions of the basal ganglia:
Lesions in specific nuclei tend to produce characteristic deficits. One well-known disorder is
Parkinson's disease, which is the slow and steady loss of dopaminergic neurons in SNpc. An
instant Parkinson-like syndrome will result if these neurons are damaged. This happened several
years ago to an unfortunate group of people who took some home-brewed Demerol in search of a
high. I t was contaminated by a very nasty byproduct, M PTP ,which selectively zapped the SNpc
neurons. The three symptoms usually associated with Parkinson's are tremor, rigidity, and
bradykinesia. The tremor is most apparent at rest. Rigidity is a result of simultaneous contraction
of flexors and extensors, which tends to lock up the limbs. Bradykinesia, or "slow movement", is a
difficulty initiating voluntary movement, as though the brake cannot be released.
Huntington's disease, or chorea, is a hereditary disease of unwanted movements. I t results from
degeneration of the caudate and putamen, and produces continuous dance-like movements of the
face and limbs. A related disorder is hemiballismus, flailing movements of one arm and leg, which
is caused by damage (i.e., stroke) of the subthalamic nucleus.
D. The cerebellum:
The cerebellum is involved in the coordination of movement. A simple way to look at its purpose is
that it compares what you thought you were going to do (according to motor cortex) with what is
actually happening down in the limbs (according to proprioceptive feedback), and corrects the
movement if there is a problem. The cerebellum is also partly responsible for motor learning, such
as riding a bicycle. Unlike the cerebrum, which works entirely on a contralateral basis, the
cerebellum works ipsilaterally.
The cerebellum ("little brain") has convolutions similar to those of cerebral cortex, only the folds
are much smaller. Like the cerebrum, the cerebellum has an outer cortex, an inner white matter,
and deep nuclei below the white matter.
Single folium, enlarged
5. Cat cerebellum, sagittal section
I f we enlarge a single fold of cerebellum, or a folium, we can begin to see the organization of cell
types. The outermost layer of the cortex is called the molecular layer, and is nearly cell-free.
I nstead it is occupied mostly by axons and dendrites. The layer below that is a monolayer of large
cells called Purkinje cells, central players in the circuitry of the cerebellum. Below the Purkinje
cells is a dense layer of tiny neurons called granule cells. Finally, in the center of each folium is the
white matter, all of the axons traveling into and out of the folia.
These cell types are hooked together in stereotypical ways throughout the cerebellum.
M ossy fibers are one of two main sources of input to the cerebellar cortex. A mossy fiber is an
axon terminal that ends in a large, bulbous swelling. These mossy fibers enter the granule cell
layer and synapse on the dendrites of granule cells (right); in fact the granule cells reach out with
little "claws" to grasp the terminals. The granule cells then send their axons up to the molecular
layer, where they end in a T and run parallel to the surface. For this reason these axons are called
parallel fibers. The parallel fibers synapse on the huge dendritic arrays of the Purkinje cells.
However, the individual parallel fibers are not a strong drive to the Purkinje cells. The Purkinje
cell dendrites fan out within a plane, like the splayed fingers of one hand. I f you were to turn a
Purkinje cell to the side, it would have almost no width at all. The parallel fibers run
perpendicular to the Purkinje cells, so that they only make contact once as they pass through the
dendrites.
6. Although each parallel fiber touches each Purkinje cell only once, the thousands of parallel fibers
working together can drive the Purkinje cells to fire like mad.
The second main type of input to the folium is the climbing fiber. The climbing fibers go straight
to the Purkinje cell layer and snake up the Purkinje dendrites, like ivy climbing a trellis. Each
climbing fiber associates with only one Purkinje cell, but when the climbing fiber fires, it provokes
a large response in the Purkinje cell.
The Purkinje cell (left) compares and processes the varying inputs it gets, and finally sends its own
axons out through the white matter and down to the deep nuclei. Although the inhibitory Purkinje
cells are the main output of the cerebellar cortex, the output from the cerebellum as a whole comes
from the deep nuclei. The three deep nuclei are responsible for sending excitatory output back to
the thalamus, as well as to postural and vestibular centers.
There are a few other cell types in cerebellar cortex, which can all be lumped into the category of
inhibitory interneuron. The Golgi cell is found among the granule cells. The stellate and basket
cells live in the molecular layer. The basket cell (right) drops axon branches down into the
Purkinje cell layer where the branches wrap around the cell bodies like baskets.
E. I nputs and outputs of the cerebellum:
The cerebellum operates in 3's: there are 3 highways leading in and out of the cerebellum, there
are 3 main inputs, and there are 3 main outputs from 3 deep nuclei. They are:
The 3 highways are the peduncles, or "stalks". There are 3 pairs: the inferior, middle, and
superior peduncles.
7. The 3 inputs are: M ossy fibers from the spinocerebellar pathways, climbing fibers from the
inferior olive, and more mossy fibers from the pons, which are carrying information from cerebral
cortex. The mossy fibers from the spinal cord have come up ipsilaterally, so they do not need to
cross. The fibers coming down from cerebral cortex, however, DO need to cross (remember the
cerebrum is concerned with the opposite side of the body, unlike the cerebellum). These fibers
synapse in the pons (hence the huge block of fibers in the cerebral peduncles labeled
"corticopontine"), cross, and enter the cerebellum as mossy fibers.
The 3 deep nuclei are the fastigial, interposed, and dentate nuclei. The fastigial nucleus is
primarily concerned with balance, and sends information mainly to vestibular and reticular
nuclei. The dentate and interposed nuclei are concerned more with voluntary movement, and send
axons mainly to thalamus and the red nucleus.
Professor Yasser Metwally
www.yassermetwally.com