H1: Introduction
1. Terminology
Perception= being aware of what is happening around you, makes you do an action
primary visual area V1 + somatosensory cortex S1 + auditory cortex A1
Action= sends info to muscles motor area
Reasoning= thinking about what you need to do prefrontal cortex + temporal
association cortex
TRIANGLE IS BASIS OF EVERY PROCESS IN BRAIN!
Ipsilateral= something happens at same side of body
Contralateral= something happens on opposite side of body
Midsagittal slices= cut at midline
Coronal slices= cut in the brain, anterior to posterior slices
2. The nervous system
Central nervous system= brain + spinal chord + eye + optical
nerve
CEREBRAL CORTEX HAS EXPANDED TREMENDOUSLY IN
HUMANS!
A. Central nervous system
Gyri= winding that goes up
Sulci= winding that goes down
Increases surface area more function can be imbedded in brain
DIFFERENCES LIKENESSES
Amount of gyrification Big cerebrum + small cerebellum
Brainsize: dolphin brain bigger (sleep 2 hemispheres + brain stem + spinal
one hemisphere at a time) chord
Size of olfactory bulb: rats have big
bulbs (nocturnal, rely more on smell)
a) Cerebrum: sensation + movement + reasoning info on left side goes
to right side of brain
b) Cerebellum: movement control center info on left side goes to left
side of brain
More neurons than cerebrum!
c) Brain stem: relay info from PNS to brain + vital functions (breathing,
consciousness, control of body T)
d) Spinal cord: conduit info from body to brain transection: paralysis + lack of feeling
1
, B. Peripheral nervous system
a) Spinal cord (CNS)
b) Spinal nerves
c) Dorsal + ventral root
Somatic + visceral NS
1. Sensory neurons with info from body
2. Dorsal root ganglia: place where cell bodies of sensory
neurons are
3. Info moves via brain and back to spinal chord
4. Make synaps in butterfly shape with motor neuron
5. Motor neuron leaves spinal cord via ventral root
KNEE REFLEX MOVES ONLY IN SPINAL CHORD
Cranial nerves= innervate the head, arise from the brain stem (12 pairs) some are CNS, some are
PNS (somatic + visceral)
Optic nerve (vision): CNS + trigeminus (somatosensory info from face skin): sPNS + nervus
vagus (internal organs of chest/abdomen): vPNS
3. The brian
A. Meninges
a) Dura mater= hard, outer protective layer with blood vessels can’t
see gyri
b) Subdural space
c) Arachnoid membrane
d) Subarachnoid space: large space filled with cerebrospinal fluid
e) Pia mater= softer protective layer
PROTECTS BRAIN + SPINAL CHORD!
Subdural hematoma= bleed in subdural space, causes pressure on brain (skull + dura mater can’t
expand) burr holes in skull to relieve pressure!
B. Ventricular system
1. Cerebrospinal fluid produced by choroid plexus (located in ventricles)
2. CSF circulates to back of brain move through tiny openings behind
cerebellum
3. Push CSF in outer side of brain subarachnoid space
4. Via arachnoid villus taken up by blood vessels
Hydrocephalus/ swelling of ventricles= disruption of normal CSF flow because of
tumor that block one of ventricles occurs naturally in children
Place shunt from brain to abdomen
Symptoms: extreme headaches, dizziness, vision loss
2
, C. Diagnosing brain abnormaliti es
CT scan X-ray based anatomical imaging
Take pictures of different sections of brain
INFO ABOUT ANATOMY
MRI Magnetic field around you interacts with H-atoms in brain
Tumor attracts more water
INFO ABOUT ANATOMY
fMRI About oxygen use more active areas use more oxygen
INFO ABOUT FUNCTION
Diffusion tensor imaging Looks at bundle of axons
PET Positron emission tomography
Detection of changes in blood flow and metabolism
Neuronal activity= glucose and oxygen consumption
4. Understanding CNS structure through development
1. After gastrulation: formation endo- and ectoderm
2. Formation primitive streak production mesoderm (first
signs of brain + NS)
3. Neurulation (day 17-22 after conception in humans)
4. Mesoderm cells notochord
5. Signals from notochord inward folding of ectoderm at
neural plate
6. Ends of neural plate fuse + disconnect neural tube
a) Notochord forms vertebrae (internal surroundings from
immediate spinal chord)
b) Neural tube forms brain
c) Somites form outer vertebrae
NEURAL TUBE FIRST CLOSES IN MIDDLE, THAN TOWARDS ANTERIOR + POSTERIOR!
Neural tube defects= anterior (anencephaly) or posterior (spina bifida) site can not be closed,
deficiency in folic acid (1/500)
Development of the brain
Differentiation of neural tube into 3 primary vesicles: prosencephalon/forebrain +
mesencephalon/ midbrain + rhombencephalon/hindbrain
A. DIFFERENTIATION OF FOREBRAIN (PROSENCEPHALON )
1. Forebrain: telencephalic vesicles + diencephalon + optic vesicles (make retina +
optic nerve)
2. Telencephalic vesicles grow + lie over diencephalon
3. Production new vesicles + olfactory bulbs
4. Cells of wall of telencephalon divide + differentiate into various structures
5. Proliferation of neurons in ventricle wall + axon growth
6. White matter systems develop
3
, NEURONS GROW FROM INSIDE TO OUTSIDE: NEW CELLS START FROM BOTTOM + WORK THEIR WAY
UP TO FORM NEW LAYERS!
Gray matter= mainly cell bodies (axons + dendrites)
White matter= mainly myelinated axons conduct signals in fast way
Corpus callosum= link info from both hemispheres together very fast
Function:
1) Intelligence + memory + perception + conscious awareness + cognition
2) Info from eye, ear, skin via thalamus (in diencephalon) to cerebral cortex
Eye goes directly to brain, ear + skin have other step in brainstem
B. DIFFERENTIATION OF MIDBRAIN (MESENCEPHALON )
Mesencephalon= cell groups regulating consciousness + mood + pain + pleasure
Less drastic development!
Cerebral aqueduct= passageway for CSF tumor: close off passageway of CSF to
ventrical
Substantia nigra, red nucleus: voluntary movement
C. DIFFERENTIATION OF HINDBRAIN (RHOMBENCEPHALON )
Rhombic lips= will form cerebellum
Movement control
Medullary pyramids= sensory functions (audition + taste + touch)
Pyramidal decussation= neuron from motor cortex receives info on ipsilateral site and crosses over to
contralateral site in hindbrain
D. DIFFERENTIATION OF THE SPINAL CHORD
Interneurons lie in intermediate zone (in spinal gray matter)
4
1. Terminology
Perception= being aware of what is happening around you, makes you do an action
primary visual area V1 + somatosensory cortex S1 + auditory cortex A1
Action= sends info to muscles motor area
Reasoning= thinking about what you need to do prefrontal cortex + temporal
association cortex
TRIANGLE IS BASIS OF EVERY PROCESS IN BRAIN!
Ipsilateral= something happens at same side of body
Contralateral= something happens on opposite side of body
Midsagittal slices= cut at midline
Coronal slices= cut in the brain, anterior to posterior slices
2. The nervous system
Central nervous system= brain + spinal chord + eye + optical
nerve
CEREBRAL CORTEX HAS EXPANDED TREMENDOUSLY IN
HUMANS!
A. Central nervous system
Gyri= winding that goes up
Sulci= winding that goes down
Increases surface area more function can be imbedded in brain
DIFFERENCES LIKENESSES
Amount of gyrification Big cerebrum + small cerebellum
Brainsize: dolphin brain bigger (sleep 2 hemispheres + brain stem + spinal
one hemisphere at a time) chord
Size of olfactory bulb: rats have big
bulbs (nocturnal, rely more on smell)
a) Cerebrum: sensation + movement + reasoning info on left side goes
to right side of brain
b) Cerebellum: movement control center info on left side goes to left
side of brain
More neurons than cerebrum!
c) Brain stem: relay info from PNS to brain + vital functions (breathing,
consciousness, control of body T)
d) Spinal cord: conduit info from body to brain transection: paralysis + lack of feeling
1
, B. Peripheral nervous system
a) Spinal cord (CNS)
b) Spinal nerves
c) Dorsal + ventral root
Somatic + visceral NS
1. Sensory neurons with info from body
2. Dorsal root ganglia: place where cell bodies of sensory
neurons are
3. Info moves via brain and back to spinal chord
4. Make synaps in butterfly shape with motor neuron
5. Motor neuron leaves spinal cord via ventral root
KNEE REFLEX MOVES ONLY IN SPINAL CHORD
Cranial nerves= innervate the head, arise from the brain stem (12 pairs) some are CNS, some are
PNS (somatic + visceral)
Optic nerve (vision): CNS + trigeminus (somatosensory info from face skin): sPNS + nervus
vagus (internal organs of chest/abdomen): vPNS
3. The brian
A. Meninges
a) Dura mater= hard, outer protective layer with blood vessels can’t
see gyri
b) Subdural space
c) Arachnoid membrane
d) Subarachnoid space: large space filled with cerebrospinal fluid
e) Pia mater= softer protective layer
PROTECTS BRAIN + SPINAL CHORD!
Subdural hematoma= bleed in subdural space, causes pressure on brain (skull + dura mater can’t
expand) burr holes in skull to relieve pressure!
B. Ventricular system
1. Cerebrospinal fluid produced by choroid plexus (located in ventricles)
2. CSF circulates to back of brain move through tiny openings behind
cerebellum
3. Push CSF in outer side of brain subarachnoid space
4. Via arachnoid villus taken up by blood vessels
Hydrocephalus/ swelling of ventricles= disruption of normal CSF flow because of
tumor that block one of ventricles occurs naturally in children
Place shunt from brain to abdomen
Symptoms: extreme headaches, dizziness, vision loss
2
, C. Diagnosing brain abnormaliti es
CT scan X-ray based anatomical imaging
Take pictures of different sections of brain
INFO ABOUT ANATOMY
MRI Magnetic field around you interacts with H-atoms in brain
Tumor attracts more water
INFO ABOUT ANATOMY
fMRI About oxygen use more active areas use more oxygen
INFO ABOUT FUNCTION
Diffusion tensor imaging Looks at bundle of axons
PET Positron emission tomography
Detection of changes in blood flow and metabolism
Neuronal activity= glucose and oxygen consumption
4. Understanding CNS structure through development
1. After gastrulation: formation endo- and ectoderm
2. Formation primitive streak production mesoderm (first
signs of brain + NS)
3. Neurulation (day 17-22 after conception in humans)
4. Mesoderm cells notochord
5. Signals from notochord inward folding of ectoderm at
neural plate
6. Ends of neural plate fuse + disconnect neural tube
a) Notochord forms vertebrae (internal surroundings from
immediate spinal chord)
b) Neural tube forms brain
c) Somites form outer vertebrae
NEURAL TUBE FIRST CLOSES IN MIDDLE, THAN TOWARDS ANTERIOR + POSTERIOR!
Neural tube defects= anterior (anencephaly) or posterior (spina bifida) site can not be closed,
deficiency in folic acid (1/500)
Development of the brain
Differentiation of neural tube into 3 primary vesicles: prosencephalon/forebrain +
mesencephalon/ midbrain + rhombencephalon/hindbrain
A. DIFFERENTIATION OF FOREBRAIN (PROSENCEPHALON )
1. Forebrain: telencephalic vesicles + diencephalon + optic vesicles (make retina +
optic nerve)
2. Telencephalic vesicles grow + lie over diencephalon
3. Production new vesicles + olfactory bulbs
4. Cells of wall of telencephalon divide + differentiate into various structures
5. Proliferation of neurons in ventricle wall + axon growth
6. White matter systems develop
3
, NEURONS GROW FROM INSIDE TO OUTSIDE: NEW CELLS START FROM BOTTOM + WORK THEIR WAY
UP TO FORM NEW LAYERS!
Gray matter= mainly cell bodies (axons + dendrites)
White matter= mainly myelinated axons conduct signals in fast way
Corpus callosum= link info from both hemispheres together very fast
Function:
1) Intelligence + memory + perception + conscious awareness + cognition
2) Info from eye, ear, skin via thalamus (in diencephalon) to cerebral cortex
Eye goes directly to brain, ear + skin have other step in brainstem
B. DIFFERENTIATION OF MIDBRAIN (MESENCEPHALON )
Mesencephalon= cell groups regulating consciousness + mood + pain + pleasure
Less drastic development!
Cerebral aqueduct= passageway for CSF tumor: close off passageway of CSF to
ventrical
Substantia nigra, red nucleus: voluntary movement
C. DIFFERENTIATION OF HINDBRAIN (RHOMBENCEPHALON )
Rhombic lips= will form cerebellum
Movement control
Medullary pyramids= sensory functions (audition + taste + touch)
Pyramidal decussation= neuron from motor cortex receives info on ipsilateral site and crosses over to
contralateral site in hindbrain
D. DIFFERENTIATION OF THE SPINAL CHORD
Interneurons lie in intermediate zone (in spinal gray matter)
4
