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Table Of Contents:
What’s included: Ready-to-study anatomy, physiology and pathology notes of the nervous
system & special senses presented in succinct, intuitive and richly illustrated downloadable PDF
documents. Once downloaded, you may choose to either print and bind them, or make
annotations digitally on your iPad or tablet PC.

Free Bonus: ‘Neurology’, ‘Neurosurgery & ‘Ophthalmology’ chapters of Toronto Notes for
reference and further detailed reading.

File List:
• Development & Organisation of the Nervous System
• The Nervous System In Detail
• Blood Vessels of the Brain
• Neurotransmission
• Memory
• Neurobiology of Emotions
• Somatosensory Processing
• Motor Processing
• The Peripheral Nervous System
• Cranial Nerves & Their Pathways
• Special Senses; Vision, Taste, Smell, Hearing & Equilibrium
• Pain & Nociception
• Important Clinical Neurological Things
• Brain Tumours
• Central Nervous System Infections
• Dementias
• Ear Pathology
• Epilepsy
• Equilibrium Disorders
• Guillian-Barre Syndrome
• Hearing Disorders
• Herpetic Neuralgia (Shingles)
• Huntingtons Disease
• Intracranial Haemorrhages
• Ischaemic Encephalopathy
• Motor Neurone Diseases & Polio
• Multiple Sclerosis & Leukodystrophies
• Myaesthenia Gravis
• Neurosyphilis
• Overview of Disorders of the Special Senses
• Parkinsons Disease
• Peripheral Neuropathies
• Prion Diseases
• Raised Intracranial Pressure
• Spinal Cord Syndromes
• Strokes
• Traumatic Brain Injuries
• Vision Disorders
• TORONTO - Neurology & Neurosurgery
• TORONTO - Ophthalmology
 Week 1
Neuroscience Notes
Development & Organisation of the Nervous System

The Nervous System - Overview:
• Macro Structures:
o Brain
o Spinal Chord
o Peripheral Nerves
o Sense Organs
§ Eyes
§ Ears
§ Tongue
§ Olfactory bulbs
§ Skin
• Functions:
o Detection of stimuli (external/internal)
o Response to stimuli
o Coordinates activity of other organs & systems

Organisation of the Nervous System:
• Central Nervous System (the “CPU” & “Motherboard”)
o Brain
o Spinal Cord
• Peripheral Nervous System (the “Cables”)
o Cranial Nerves & Spinal Nerves
o Communication between CNS & rest of body

Nervous
System

Central Nervous Peripheral

System Nervous System
(Brain & Spinal (Cranial Nerves
Cord) & Spinal Nerves)

Afferent
Efferent
(Incoming)
(Out-going)
- Sensory

Somatic
(Voluntary) Autonomic
(Involuntary)
- Motor Function

Sympathetic NS Parasympathetic NS
(Fight/Flight) (Rest & Digest)

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General Embryonic Development is Described as Either:
• Trimesters (3x 3-Month Periods):
o First: - Foundations of Major Organs
o Second: - Development of Organs
o Third: - Rapid Growth & Fully Functional Organs.
• OR... Anatomical Stages: **(These are more relevant)
o Pre-Embryonic Period: 0-2 Weeks
§ Fertilisation
§ Blastocyst Formation & Implantation
§ Gastrulation
o Embryonic Period: 3-8 Weeks
§ Development & Differentiation of 3 Germ Layers into foundations of Organs.
o Foetal Period: 9 Weeks à Birth.
§ Period of Growth, NOT Differentiation.

Embryonic Development of the Nervous System:
1. Blastocyst: (Pre-Embryonic Period)
a. A fertilised egg reaches the Morula stage (Day 3), differentiates into a Blastocyst (Day 7) and then
implants in the endometrium.
b. The implanted Blastocyst consists of an ‘Inner-Cell Mass’ surrounded by Trophoblasts.
c. This ‘Inner-Cell Mass’ differentiates to form the ‘Bilaminar Disc’ (2 layers of cells)
i. Epiblast Layer: The top layer of Columnar Cells.
ii. Hypoblast Layer: The bottom layer of Cuboidal Cells.

2. Gastrulation: (Embryonic Period [wk 3+])
a. Gastrulation = the process that establishes the 3 Primary Germ Layers in the Embryo.
b. Begins with formation of the Primitive Streak (a shallow midline groove) along the caudal/tail half of
bilaminar disc.
c. At the cephalic/head end of the Primitive Streak is the Primitive Node which surrounds the small
Primitive Pit. Cells of the Epiblast proliferate & migrate through the Primitive pit into the gap
between the Epiblast & the Hypoblast. This is known as Invagination.
d. The Epiblast then becomes the Ectoderm, the invaginated cells become the Mesoderm and the
Hypoblast becomes the Endoderm.

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 3. Neurulation:
a. Neurulation = Where the ectoderm around the midline thickens to form an elevated Neural Plate.
b. This Neural Plate invaginates to form a Neural Groove down the midline, flanked by 2 Neural Folds.
The Notochord, a flexible rod of mesoderm-derived cells, defines the primitive axis of the embryo.
c. The outer edges of the 2 Neural Folds continue folding towards the midline where they fuse
together to form the Neural Tube. (NB: Initially this happens around the centre of the embryo,
leaving open Neural Grooves at both the Cephalic & Caudal ends. However, these Neural Grooves,
aka Neuropores, close off by around wk 6 of development. Failure of a Neuropore to close can result
in Neural Tube Defects such as Spina-Bifida )
d. The hollow part inside the Neural Tube is called the Neurocoele.
e. The Neural Tube then separates from the Ectoderm and sinks down to the level of the Mesoderm.
i. The Mesoderm that flanks the sunken Neural Tube develops into The Somites, which
eventually become the Skin, Skeletal Muscle & Vertebrae+Skull.
f. Next, some cells on the top of the Neural Tube differentiate and separate to form the Neural Crest.
Cells of the Neural Crest eventually migrate & give rise to Peripheral Sensory Neurons, Autonomic
Neurons & Sensory Ganglia of the spinal nerves.

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The Somites:
• Somites = The Mesoderm Tissue directly adjacent to Neural Tube.
o The Mesoderm that flanks the sunken Neural Tube develops into The Somites, which eventually
become the Skin, Skeletal Muscle & Vertebrae+Skull.
• Somites grow in association with the developing nervous system à establish early connections.
• Somites differentiate into 3 regions:
o Sclerotome: Becomes the Vertebral Column & Skull
o Myotome: Becomes Skeletal Muscle
o Dermatome: Becomes Skin
• Hence, the Somites determine the distribution of Nervous Supply to all Mesoderm-Derived Tissue.

Development of the Neural Tube Into the Spinal Cord:
1. Once the Neural Tube closes, the cells differentiate into Neuroblasts.
2. These Neuroblasts give rise to 2 concentric layers, The Mantle Layer (Inner) and The Marginal Layer (Outer).
a. Mantle Layer: Later forms the Grey-Matter of the Spinal Cord. (Ventral & Dorsal ‘Horns’)
b. Marginal Layer: Later forms the White-Matter of the Spinal Cord.
3. The Dorsal & Ventral regions of the Mantle Layer thicken forming 2xBasal Plates, and 2xAlar Plates.
a. Basal Plates: (Motor Plates) Develop into Motor Neurons innervating skeletal muscles.
i. Become the Ventral Horns
b. Alar Plates: (Sensory Plates) Develop into Sensory Neurons.
i. Become the Dorsal Horns
- NB: The Lateral Horns in the Thoracic & Lumbar Regions of the Spinal Cord are Autonomic Motor Neurons
and their Axons exit via the Ventral Roots.

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Development of the Neural Crest cells Into the Sensory (‘Dorsal-Root’) Ganglia of PNS:
1. Neural Crest Cells also differentiate into Neuroblasts which become the Sensory (‘Dorsal-Root’) Ganglia.
2. The Neuroblasts of the Dorsal-Root Ganglia develop 2 processes:
a. Penetrates into the Alar Plate of the Neural Tube AND/OR into the Marginal Layer & up to brain.
b. Grows distally (outwards) and integrates with the Ventral Motor Root, forming the Trunk of the
Spinal Nerve. These neurons eventually terminate in the sensory receptors in skin/muscle/tendons.
NB: These Dorsal-Root Ganglia Processes form the ‘Sensory PseudoUnipolar’ Nerve-Type.

NB: By Wk 7 we have a Nearly-Functional Nervous System very similar in Organisation to Adult Anatomy.

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Development of the Head & Brain:
1. Neural-Tube Enlargement (Cephalic End):
a. At around 3-4wks, the Cephalic portion of the Neural Tube enlarges to form 3 regions; the Primary
Brain Vesicles:
i. Prosencephalon (Fore Brain)
ii. Mesencephalon (Mid Brain)
iii. Rhombencephalon (Hind Brain)
NB: The Cephalic Flexure between the Prosencephalon & Mesencephalon – important in humans for
Bipedalism (Brain @ 900 to Spinal Cord).

b. By around 4-5wks, the Primary Brain Vesicles develop further:
i. Prosencephalon (Fore Brain) develops into:
1. Telencephalon (Future Cerebral Hemispheres)
2. Diencephalon (Future Thalamus & Hypothalamus)
ii. Mesencephalon (Mid Brain)
iii. Rhombencephalon (Hind Brain) develops into:
1. Metencephalon (Future Pons & Cerebellum)
2. Myelencephalon (Future Medulla)

2. Brain Formation:
a. At around 11wks, there is massive Proliferation of Neuroblasts in Cephalic Neural Tube, causing
folding due to lack of space within the cranium.

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 3. Pharyngeal Arches & Cranial Nerves:
a. Pharyngeal Arches = Similar to the Somites in lower parts of embryo. Each Pharyngeal Arch consists
of:
i. Ectoderm Tissue à Cranial Nerves & Skin of Face.
ii. Mesenchyme (Mesoderm) Tissue à Musculature of Face & Neck
iii. Endoderm Tissue à Pharyngeal Epithelium.
b. NB: Essentially, this results in Segmental Development of the Head & Neck, similar to Somites.

4. Formation of Ventricles:
a. The Neurocoel of the Neural Tube becomes the Ventricles of the Adult Brain.

i. Lateral Ventricles (Vent. 1 & 2):
1. Sits in the Cerebral Hemispheres (Telencephalon)
2. Are shaped due to folding of brain during development.
3. Each Consists of:
a. An Frontal (Anterior) Horn
b. A ‘Body’
c. An Occipital (Posterior) Horn
d. A Temporal (Inferior) Horn
ii. Third Ventricle:
1. Sits in the Diencephalon
2. Lateral Walls formed by Thalamus & Hypothalamus
3. Connects with the 4th Ventricle via the Cerebral Aqueduct.
iii. Fourth Ventricle:
1. Sits in the Brainstem
2. Is Continuous with the Spinal Canal (Central Canal).

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 GLS STUFF:
Terminology:
- “Rostral” = Head
- “Caudal” = Tail
- “Dorsal” = Back
- “Ventral” = Front
- “Ganglia” = Groups of Nerve-Cell Bodies
- “Gyrus” = Elevations (Crests) of the folds on the Cerebral Cortex.
- “Sulcus” = Grooves / Furrows between the Gyri on the Cerebral Cortex.

Anatomy of the Brain:
- Surface Anatomy
o Dorsal Landmarks:
§ Longitudinal Fissure: Separates Left & Right Hemispheres
§ Central Sulcus: Separates the Frontal & Parietal Lobes.
§ Lateral Sulcus: Separates the Temporal Lobe from the Other Lobes.
§ Occipital Lobe: Most Caudal Lobe (Visual Cortex)
§ Colliculi: Nestled in between the Cerebrum & Cerebellum.
• 2x Superior: Controls eye movements
• 2x Inferior: Part of Auditory Pathway

Brain Stem (Note the Colliculi – Superior & Inferior)

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o Ventral Landmarks:
§ Optic Chiasm (“Optic Crossing”): ‘X’-shaped crossing-over of Optic Nerves.
§ Hypothalamus:
§ Infundibulum: Connection between Pituitary & Hypothalamus.
§ Pituitary:
§ Olfactory Bulbs:
§ Mamillary Bodies:

o Medial Landarks (Ie. On Sagital Section):
§ Cingulate Gyrus
§ Corpus Callosum
§ Lateral Ventricle
§ Pineal Body
§ Thalamus
§ Hypothalamus

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o Coronal Section Landmarks:
§ Cortex (Grey Matter)
§ White Matter
§ Lateral Ventrcile
§ Caudate Nucleus
§ Corpus Striatum
§ Thalamus
§ Massa Intermedia: The Bridge between the Left & Right Thalamus.
§ Hippocampus

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 System: Neurological

Nervous System:
- Central Nervous System (CNS)
o Brain & Spinal Chord
o Integrating command centre
- Peripheral Nervous System (PNS)
o Outside the CNS
o Nerves extending to and from the periphery and CNS

The Neuron:
Structural Features:
a) Receptive Field: Dendrites
o Stimulated by inputs
b) Cell Body: Soma
o Responds to graded inputs
c) Efferent Projection: Axon (and axon hillock)
o Conducts nerve impulses to target
o Myelinated and unmyelinated
d) Efferent Projection: Myelin Sheath
e) Efferent Projection: N de f Ra ie
f) Output: Synaptic Terminals

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Supporting Cells:
Neuroglia (Glia)
o Smaller support cells of NS
o Outnumber neurons 10:1
o Structural & mechanical support
o Roles in maintaining homeostasis
o Myelination
o Immune responses via phagocytosis.
o Types of neuroglia:
CNS:
Astrocytes
o Nutrient bridge between neuron & capillaries
o Guide migrating young neurons
o Synapse formation
o Mop up excess K+ ions + neurotransmitters
Oligodendrocytes
o Myelin formation in CNS
Microglia
o Long thorny processes
o Monitors neuron health
o Senses damaged neurons
o Migrates to damaged neuron
o Phagocytoses microbes & debris (immune cells are denied access to CNS)
Ependymal Cells
o Lines central cavities of brain + spinal chord
o Blood-brain barrier
o Beating cilia circulates cerebrospinal fluid
PNS:
Schwann Cells
o Myelin Formation – wrap around axon
o Regeneration of damaged neurons
Satellite cells
o Surround neuron bodies

tructure, nutritional support & protection.

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Connective Tissue Sheaths on Peripheral Nerves:
Endoneurium
o Delicate connective tissue layer
o Surrounds each axon
Perineurium
o Coarser connective tissue layer
o Bundles groups of fibres into fascicles
Epineurium
o Tight, fibrous sheath
o Bundles fascicles into a single nerve.
o Houses blood vessels

Grey Matter & White Matter:

Grey Matter
o Neuron bodies (Soma)
o Imbedded in neuroglial cells
o Eg:
Cortex of Brain
Centre of Spinal Chord
Ganglia/nuclei

White Matter
o Neuron fibres (axons & dendrites
o White due to myelin
o Eg:
Peripheral Nerves & Plexuses
Central fibre tracts

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 Anatomy of the Brain:

Surface Anatomy
- Dorsal Landmarks:
o Longitudinal Fissure: Separates Left & Right Hemispheres
o Central Sulcus: Separates the Frontal & Parietal Lobes.
o Lateral Sulcus: Separates the Temporal Lobe from the Other Lobes.
o Occipital Lobe: Most Caudal Lobe (Visual Cortex)
o Colliculi: Nestled in between the Cerebrum & Cerebellum.
2x Superior: Controls eye movements
2x Inferior: Part of Auditory Pathway

- Ventral Landmarks:
o O ic Chia m O ic C o ing ‘X’-shaped crossing-over of Optic Nerves.
o Hypothalamus:
o Infundibulum: Connection between Pituitary & Hypothalamus.
o Pituitary:
o Olfactory Bulbs:
o Mamillary Bodies:

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- Medial Landarks (Ie. On Sagital Section):
o Cingulate Gyrus
o Corpus Callosum
o Lateral Ventricle
o Pineal Body
o Thalamus
o Hypothalamus

- Coronal Section Landmarks:

o Cortex (Grey Matter)
o White Matter
o Lateral Ventrcile
o Caudate Nucleus
o Corpus Striatum
o Thalamus
o Massa Intermedia: The Bridge between the Left & Right Thalamus.
o Hippocampus

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 Blood Vessels & Blood Flow to the Brain

Arterial Supply of the Brain:

- Brain is Supplied by 2 Arterial Systems:
o 2x Vertebral Arteries 1x Basilar Artery Circle of Willis
o 2x Internal Carotid Arteries Circle of Willis
- Ci cle of Willi The Ana omo i of he B ain
o (The Ro ndabo of Arteries on the underside of the Brain with multiple Roads coming off it)
o (Encircles the Optic Chiasma, The Pituitary Gland & the Mammillary Bodies.)
o The R ad : (Anterior Posterior)
2x Anterior Cerebral Arteries
1x Anterior Communicating Artery
2x Internal Carotid Arteries
2x Middle Cerebral Arteries
2x Posterior Communicating Arteries
2x Posterior Cerebral Arteries
1x Basilar Artery
o NB: Communicating Arteries are always patent, but generally not functional (no blood flow) when
blood flow from both Carotids & Basilar Arteries is normal. However, if blood flow from one of the
major arteries is impeded, blood is shunted through the Communicating Arteries to compensate.

Distribution of Cerebral Arteries:

- Anterior Cerebral Arteries:
o (Travels up and over the Corpus Callosum, sprouting branches outwards towards the cortex)
o Medial Portion of Frontal Lobe (Incl. Cortex)
o Medial Portion of Parietal Lobe (Incl. Cortex)
o Corpus Callosum
- Middle Cerebral Arteries:
o (Travels through the Lateral Fissure/Sulcus and emerges onto the Lateral Surface of the Brain)
o Lateral Portion of the Frontal Lobe (Incl. Cortex)
o Lateral Portion of the Parietal Lobe (Incl. Cortex)
o Entire Temporal Lobe (Incl. Cortex)
- Posterior Cerebral Arteries:
o (Travels along the Inferior brain surface between the Cortex and the Cerebellum)
o Inferior Portion of Temporal Lobe (Incl. Cortex)
o Posterio-Medial Portion of Parietal Lobe (Incl. Cortex)
o Entire Occipital Lobe (Incl. Cortex)

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Venous Drainage of the Brain Via D al Sin e
- Venous Drainage begins with venous blood collecting in small venous channels known as “Dural Sinuses”.
- Sinuses Sit Within The Dura-Mater:
o The Dura-Mater is the thickest & outermost of the 3 Meninges of the brain. It extends deep into
the brain in 2 locations, the Falx Cerebri & the Tentorium Cerebelli:
1. Falx Cerebri:
The Dura Mater folds deep into the Longitudinal Fissure (Falx Cerebri) of the brain,
where it forms 2 Sinuses:
o 1. A Triangular S e io Sagi al Sin at the top of the dural fold.
o 2. A lower Infe io Sagi al Sin at the bottom of the dural fold.

2. Tentorium Cerebelli:
The Dura Mater folds deep into the Transverse Cerebral Fissure (Tentorium
Cerebelli) of the brain, where it forms a pair of sinuses:
o The R L T an e e Sin e .
o NB: All blood from Sup. & Inf. Sagittal Sinuses and the Straight Sinus
empties into these Transverse Sinuses.
o The L.&R. Transverse Sinuses then become the L.&R. Sigmoid Sinuses (Respectively).
o These Sigmoid Sinuses turn Inferiorly and become the Internal Jugular Veins.

Reabsorption of CSF into the Dural Sinuses:

- NB: CSF is constantly being produced, and therefore must also be constantly drained to prevent a rise in
intracranial pressure. Therefore:
- CSF is Reabsorbed into the Venous System via diffusion through Arachnoid Villi.
o Arachnoid Villi are invaginations of Arachnoid Mater through the Dura Mater and into the
Superior Sagittal Sinus.

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• Cerebral Blood Flow And Intracranial Pressure:
• Cerebral blood flow is carefully regulated under normal conditions.
• Cerebral Blood Flow:
• What percentage of cardiac output goes to the cerebral circulation at rest?
• 750ml/min (15% of cardiac output)
• Relationship Between Cerebral Blood Flow & Arterial Pressure:

• Autoregulation of Cerebral Blood Flow:

• What effect does a high PCO2 have on cerebral blood flow?
• Hypercarbia Vasodilation ↑Cerebral Blood Flow.
• What effect does a very low and very high PO2 on cerebral blood flow?
• Very High O2 Vasoconstriction
• Very Low O2 Vasodilation
• What implication does this have for the management of a patient with an acute head
injury/cerebral oedema?
• You want to prevent any hypercapnia because any vasodilation will Takes up
more room ↑Intracranial Pressure.
• You want to maintain PO2

• Kelly-Monroe Doctrine:
• States that the Cranial Compartment is Incompressible, and the Volume is Fixed.
• The Cranial Constituents (Blood, CSF, and Brain Matter) create a state of Volume
Equilibrium:
• Any increase in Volume of one of the constituents must be compensated by a
decrease in volume of another.
• Volume Buffers:
• Both CSF and, to a lesser extent, Blood Volume.
• (Eg. In Extradural Haematoma CSF & Venous Blood Volumes are Decreased)
• Maintain normal ICP
• Buffer Capacity ≈ 100-120mL

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Ganglia
Collections of neuron cell bodies in PNS
o Afferent Spinal Nerves:
Cell bodies of sensory neurons
‘Dorsal root ganglion’
o Efferent Spinal Nerves:
Cell bodies of autonomic nerve fibres
‘Sympathetic trunk ganglion’
o In Central Nervous System:
Called: Basal Nuclei / Nuclei

Spinal Nerves:
Innervation of the Skin:
o Dermatomes:
A portion of the mesoderm (skin, sensory receptors, sebaceous glands, blood vessels)
innervated by the cutaneous branches of a single spinal nerve.

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Neuronal Action Potentials:
4 Phases:
1 Resting Phase:
o Membrane is much more permeable to K+ than to Na+.
o Greater diffusion of K out than Na in
o Therefore inside is negative/Ouside is positive.
o Both Na & K voltage gated channels are CLOSED.
2 Depolarisation Phase:
o Mechanical/chemical/vibratory/other stimulus opens some Na+ channels such that Na+ flows into
the cell.
o Therefore membrane potential becomes less negative (ie. It depolarises)
o If the MP reaches approx. -55mV (threshold), the voltage gated Na+ channels open.
o Na+ influx increases dramatically – until MP reaches approx. +30mV where the voltage-gated Na+
channels close.
3 Repolarisation Phase:
o @ approx. +30mV K+ voltage gated channels open. (perm. of K increases & Na decreases)
o Large outflow of K+ membrane potential becomes more negative (repolarises) and returns to -
70mV.
4 Hyperpolarisation (undershoot) Phase:
o K+ channels remain open past -70mV and MP becomes more negative than at rest.
o K+ channels close and Na/K ATPase returns the MP to normal (-70mV)

Refractory Periods During the Action Potential:

Basically the total time between a stimulus creating an action potential and the MP returning to rest.
o Determines how soon a neuron can respond to another stimulus.
Divided into 2 sub-periods:
o Absolute Refractory Period no additional stimulus (no matter how large) can initiate a further
action potential.
o Relative Refractory Period If an additional stimulus is to initiate another action potential during
this time, it must be larger in order to reach threshold.

Speed of impulse: Dependent upon:

- 1. Axon Diameter Larger = Quicker
- 2. Presence of Myelin (white matter) Impulse jumps from exposed axon-region to the next instead of
having to open & close ion channels across the axon’s entire length (which would be slow)

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Phases of Neurotransmission:
1. Action potential reaches axon terminal, opens voltage-gated Ca+ channels.
- Influx of Ca+ into axon terminal causes vesicles of neurotransmitter to migrate to the axon terminal.
- ‘Ne o an mi e released by exocytosis from the sending (pre-synaptic) neuron.
- Neurotransmitter (acetylcholine/nor adrenaline/dopamine/glutamate/gaba/etc) diffuses across synaptic
cleft between 2 neurons.
2. Neurotransmitters bind to ligand-gated ion channels, causing change in MP of post-synaptic neuron (dendrite)
creating graded potentials.
-Short-lived, localised changes in membrane potential.
-Current flow decreases in magnitude with distance.
-The stronger the stimulus, the greater the GP (and further distance)
If GP depolarises membrane, it is excitatory
If GP hyperpolarises membrane, it is inhibitory.

- The sum of the GP may cause MP to reach threshold, triggering an action potential on the next neuron.
3. Neurotransmitter Inactivation stops continued stimulation of post-synaptic neuron.
- Neurotransmitter is either broken down by enzymes (eg. ACh-Esterase) or reabsorbed by pre-synaptic
terminal.

2 Types of Post-Synaptic Receptors:

- Ionotropic: (Ligand-Gated Ion Channels)
o Mech: Binding of Neurotransmitter Opening of Ion Channel Excitation/Inhibition of Cell.
Excitatory: Na+/Ca+ Channel – opening Na+/Ca+ Influx Depolarisation of Membrane
E ci a o Po -S na ic Po en ial (EPSP)
Inhibitory: Cl- Channel – opening Cl- Influx Hyperpolarisation of Membrane
K+ Channel – opening K+ Efflux Hyperpolarisation of Membrane
Inhibi o Po -S na ic Po en ial (IPSP)
- Metabotropic: (G-Protein Linked Receptors)
o Mech: Binding of Neurotransmitter Activates G-Protein Activates ‘Effector’ Proteins
Activate secondary Messengers (Eg. cAMP) Regulates Ion Channels/Activates Enzymes/Alters
Metabolism.

Actions of Neurotransmission:
- Direct Physiological Action:
o Eg. Neuromuscular Junction Muscle Contraction
o Eg. Sympathetic Synapse @ SA-Node ↑Heart Rate
- Links in a Chain:
o Eg. Peripheral Sensory Neuron Spinal Cord Ascending Sensory Pathways Thalamus
Cortex
- Modulation:
o Ie. Exerting a +ve/-ve influence on transmission by another neuron.

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 The Neurotransmitters

The Major Neurotransmitters (Classified by Structure):

- Amine Cla ical Ne o an mi e
o Acetylcholine (ACh)
o Dopamine
o Noradrenaline/Norepinephrine (NA/NE)
o Serotonin/5-Hydroxyl Tryptamine (5-HT)
- Amino Acids:
o Glutamate (#1 Excitatory Neurotransmitter of the Brain)
o GABA (γ-Amino Butyric Acid) (#1 Inhibitory Neurotransmitter of the Brain)
o Glycine
- Peptides:
o Cholecystokinin
o Enkephalins (Eg. Endorphins, Opioids) (Turn off Nociceptive/pain Pathways)
o Vasoactive Intestinal Peptide (VIP)

Memories
Short-Term Memory (STM):
- Based in Hippocampus.
- Lasts Seconds Several Hours MAX. (AKA: “Crammers” Memory)
- Limi ed o - Ch nk of Info.
- Amnesia ≈ Damage to Connection between STM & LTM.
Long-Term Memory (LTM):
- Limitless Capacity:
- Usually Requires STM Input:
o Generally LTM-Creation requires the info to pass through STM first.
- LTM Creation Improved by:
o Positive/Powerful Emotional State
o Rehearsal
o Association of New data with Old Data.
o The Belief that the Memory is Important
- By Remodelling the Neuron (Functionally/Structurally)
- More Specifically, Synaptic Remodelling:
- Long-Term Potentiation (LTP):
o Definition: “A Long-Lasting Post-Synaptic Depolarisation, induced through Repetitive Stimulation &
Summation of Excitatory Post-Synaptic Potentials.”
Simply – “A Persistent Increase in Synaptic Strength”
o The #1 Neurotransmitter:
Glutamate binds to NMDA and/or AMPA Receptors.
o 3 Phases of LTP:
1. Induction - (Synaptic Plasticity)
2. Expression - (Synaptic Augmentation)
3. Maintenance - (Long Term Loss/Continuation of LTP)
- 2 Types of Long-Term Memory:
o 1. Declarative (EXPLICIT):
Brain Regions:
Hippocampus
Para-Hippocampal Regions (Medial Temporal Lobe)
Areas of Cerebral Cortex
Thalamus + Hypothalamus
Learning WHAT :
Facts/Words/Ideas/Concepts/Events
o 2. Non-Declarative (IMPLICIT):
Learning HOW : - How to do things/How to recognise things.
Motor: Motor Cortex, Cerebellum,
Emotional Responses: Amygdala

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- Se en Sin of Memo (Types of Memory Deficits):
o 1. Transience
– Memory ‘Fade’
o 2. Absent-Mindedness
– Brushing teeth when already brushed them
o 3. Blocking
– When a memory is on the ‘Tip of the tongue’.
o 4. Misattribution
– Where you Misremember where you saw/heart something, or even if.
o 5. Suggestibility
- Where someone suggests that you saw/heard something (when you didn’t) and you
‘remember’ seeing/hearing it.
o 6. Bias (Negative Bias)
- Tend to recall only the Negative Things.
o 7. Persistence
- Remember a Single Failure rather than multiple successes (eg. Post Exam Briefings)
o ...8. Confabulation When you elaborate on a memory.

Intelligence - Theories:

- Theory of Multiple Intelligences:

o 7 Intelligences:
Linguistic: - Good with words/dates/names/places.
Logical-Mathematical - Good with numbers/abstract/puzzles/logic/computers
Spatial - Good with pictures/directions/jigsaws/construction/drawing
Musical - Good with sounds/notes/rhythms.
Bodily-Kinaesthetic - Good with motor/sports/mimicking/fine craft
Interpersonal - Good with people/leading /manipulation/streetwise/team/Co-op
Intrapersonal - Independent/Loner/sense of self-worth/individual/opinionated

- Emotional Intelligence:
o Properties:
Knowing your feelings/strengths/weaknesses.
Managing your emotions/motives/behaviour
Persisting despite setbacks
Empathy (good at reading other’s emotions)
o Indicators of EI:
Optimism
Taking Initiative
Achievement Motivation
o 3 Adaptive Abilities:
Appraisal & Expression of Emotion
Regulation of Emotion
Utilisation of Emotion

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 Neurobiology of Emotions
Neuroanatomy of Emotion The Limbic System:
- The Papez Circuit:
o 1. Thalamus relays Sensory Input to Cingulate Cortex.
o 2. Cingulate Cortex - gives you the Emotional Experience
- also relays to the Neocortex, which gives Context/Colouring to the Emotion.
- also relays to the Hippocampus
o 3. Hippocampus Relays to the Hypothalamus – Causes the Emotional Expression (Visceral
Response)

- ***Amygdala***:
o #1 Structure involved in Emotion The “Heart” of the Limbic System.
o “The Fight/Flight Centre”
o Linked to all but 8 areas of the Cortex :. Thought to be #1 integrator of Cognitive & Emotional
Info.
o Regulates:
Fear & Aggression
Vigilance & Attention
Recognition of Emotion (in Self & Others)
Emotional Contribution to Memory. (Emotional Implicit Memory)

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Neurotransmitters & Emotion:
- *Noradrenaline:
o Activated By:
Novel, Unexpected Stimuli
o Released By:
Locus Coeruleus (A Nucleus
In the Pons involved with
physiological responses to
stress & panic.)
- *Serotonin: What we target in treating Depression.
o Activated By:
General activity/arousal
o Released By:
Raphe Nuclei (A group of
Nuclei In the brainstem)
- *Dopamine:
o Activated By:
Pleasurable Activities
o Released By:
Ventral Tegmental Area (VTA)
Substantia Nigra
- Glutamate & GABA:
o Reduces Anxiety

Fear:
- Brain Structures Involved:
o Thalamus
Amygdala
o Thalamus
Primary Sensory Cortex
Association Cortices
- Long & Short Pathways:
o Long:
Info processed by higher brain centres & Hppocampus.
Results in a more complex response
o Short:
Info sent straight to Amygdala
Results in a basic response (Recoil from stimulus/Freeze)
Advantage = No cortical processing means quicker reaction times S i al

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