Transcript Brain Function

BRAIN FUNCTION
https://www.youtube.com/watch?v=h5f56Ynb01E
https://www.youtube.com/watch?v=mMDPP-Wy3sI
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Embryology – 3-4
Weeks
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Embryology – 4 Weeks - understand
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Embryology – 5
Weeks
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Same organization as
newborn’s
Embryology – 11
Weeks
Human Anatomy, 3rd edition
Prentice Hall, © 2001
A Child’s Brain
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Predict
•
•
•
•
Are there just a few brain neurotransmitters?
Are there over 5?
Are there over 10?
Are there over 100?
– Why would you guess that number?
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Brain Neurotransmitters - example
Human Anatomy, 3rd edition
Prentice Hall,
© 2001
Figure
9-19: The diffuse modulatory systems modulate brain function
1. Derived from amino acid
aspartate
glutamate (Glu)
γ-aminobutyric acid (GABA)
glycine (Gly)
4. Polypeptides (or
neuropeptides):
bombesin
gastrin releasing peptide
(GRP)
2. Biogenic amines
acetylcholine (Ach)
42 Brain
Neurotran
s-mitters –
examples
…and
counting!
3. Monoamines
-from phenylalanine and
tyrosine:
dopamine (DA)
norepinephrine or
noradrenaline (NE)
epinephrine or adrenaline
(Epi)
-from tryptophan:
serotonin (5hydroxytryptamine, 5HT)
melatonin (Mel)
-from histidine:
histamine (H)
Gastrins
gastrin
cholecystokinin (CCK)
Neurohypophyseals
vasopressin
oxytocin
neurophysin I
neurophysin II
Neuropeptide Y
neuropeptide Y (NY)
pancreatic polypeptide (PP)
peptide YY (PYY)
Opioids
corticotropin
(adrenocorticotropic hormone,
ACTH)
Beta-lipotropin
dynorphin
endorphin
Human Anatomy, 3rd edition
enkephaline
Prentice
Hall, © 2001
leumorphin
4. cont’d Polypeptides (or
neuropeptides):
Secretins
secretin
motilin
glucagon
vasoactive intestinal peptide
(VIP)
growth hormone-releasing
factor (GRF)
Somatostatins
somatostatin
Tachykinins
neurokinin A
neurokinin B
neuropeptide A
neuropeptide gamma
substance P
Other neurotransmitters
nitric oxide (NO) no receptor
carbon monoxide (CO)
anandamide
Homunculus – distorted human shape - know what it is
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Primary Motor Cortex
Primary Sensory Cortex
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Sensory Homunculus – know what it is
Human Anatomy, 3rd edition
Motor Homunculus
– know what it is
Prentice Hall, © 2001
Adult Brain – know technical terms!
1. Forebrain (prosencephalon)
• Cerebrum (telencephalon)
• Thalamus, hypothalamus
(diencephalon)
2. Midbrain (mesencephalon)
3. Hindbrain (rhombencephalon)
• Cerebellum & pons
(metencephalon)
• Medulla oblongata
Human Anatomy, 3rd edition
(myelencephalon)
Prentice Hall, © 2001
Telencephalon (Cerebrum) - understand
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Diencephalon (Thalamus & Hypothalamus) understand
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Mesencephalon understand
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Metencephalon
(Pons) - understand
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Metencephalon
(Cerebellum) understand
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Myelencephalon
(Medulla Oblongata) understand
Human Anatomy, 3rd edition
Prentice Hall, © 2001
The Ventricles of the Brain – know this!
–Hollow areas within the brain
•Connect to spinal canal and
space around the brain
–Cerebrospinal fluid circulates
around the brain, down through
the ventricles, and into the
spinal cord.
Human Anatomy, 3rd edition
Prentice Hall, © 2001
The Ventricles of the Brain - understand
– Lateral ventricles
• Separated by the septum pallucidum (“transparent
wall”)
• Connects to third ventricle by the interventricular
foramen
– Third ventricle
• Connects to fourth ventricle by the cerebral
aqueduct
– Fourth ventricle
• Connects to the subarachnoid space and spinal
canal
– Cerebrospinal fluid circulates down through the
Human Anatomy, 3rd edition
ventricles and into
theHall,
spinal
Prentice
© 2001 cord.
https://www.youtube.com/watch?v=K9BYEO9725k
Ventricles of the Brain – find them!
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Ventricles of the Brain – find them!
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Cerebrospinal Fluid – know this!
– Composition
• Clear, colorless, watery
• Contains proteins, glucose, urea, salts
• Contains some white blood cells
– Functions
• “Floats” the brain
• Medium of transport
– Should be clear, colorless to slightly
yellowish, without red blood cells
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Problems Associated with CSF
–Hydrocephalus
–Meningitis
–Headaches
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Hydrocephalus
https://www.youtube.com/watch?v=h2_JEDTp3tg
https://www.youtube.com/watch?v=xkdiX6VXuBE
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Blood-Brain Barrier (BBB) - know
– Endothelial cells of capillaries form tight
junctions
• Lipid-soluble compounds diffuse across
• Water-soluble compounds are actively transported
across
– Differential rates of passage of certain materials
Human Anatomy, 3rd edition
Prentice Hall, © 2001
The Parts of the Brain - review
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Cerebrum – Gray & White Matter – know this!
– Outer layer – cerebral cortex
• Gray matter
– Inner portion
• White matter
• Masses of gray matter – cerebral
nuclei
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Cerebrum – Gray & White Matter – know
basic arrangement
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Cerebral Nuclei – understand
– Collections of cell bodies (gray matter)
– Mostly control the movement of skeletal
muscles
– Examples
• Caudate = “tail”
–Provides general pattern & rhythm for
walking
–Maintains arm & leg movements
• Amygdaloid = “almond-shaped”
Human Anatomy, 3rd edition
–Part of thePrentice
limbic
system
Hall, © 2001
Gyri & Sulci – know this!
Pia mater
intact on left
hemisphere
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Homunculus – know what it is
https://www.youtube.com/watch?v=CHQw7vZzZa8
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Primary Motor Cortex
Primary Sensory Cortex
Limbic System
– Functional unit (not anatomical)
– Emotional part of the brain
• Feelings of fear, loss, love, rage, etc.
– Includes parts of several anatomical
structures
• Cerebrum
• Hypothalamus
• Thalamus
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Limbic System – know major structures
https://www.youtube.com/watch?v=GDlDirzOSI8
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Hypothalamus – review
– Initiates primal drives
• Hunger, thirst, sex, rage, etc.
• Controls autonomic nervous system
–“fight or flight” sympathetic
response.
– Controls pituitary gland (“master gland”
of endocrine system)
• Infundibulum (“funnel”) funnels
secretions to the pituitary gland
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Hypothalamus – review
–Location – under thalamus
–Structure
•Clusters of nerve cell bodies
–Autonomic centers
•Infundibulum
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Thalamus – review
– Functions as a relay station between
the body and the cerebral cortex
• Inform us of our emotional state
• Relay information concerned with
motor requirements & actions
• Integrate visual and auditory
reflexes
Human Anatomy, 3rd edition
Prentice Hall, © 2001
The Thalamus – know basic location
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Epithalamus
–Location
•Above thalamus
–Contains the pineal body
•Secretes melatonin
Human Anatomy, 3rd edition
Prentice Hall, © 2001
II. Midbrain
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Midbrain – know this!
– Relay station
– Tracts of motor and sensory neurons
– Contains nuclei
• Substantia nigra secretes dopamine
–Modifies muscle tone & motor
activity
–Parkinson’s disease
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Midbrain – know basic location
Human Anatomy, 3rd edition
Prentice Hall, © 2001
III. Hindbrain
Cerebellum, Pons, & Medulla
Oblongata
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Cerebellum, Pons, Medulla Oblongata – know
basic locations
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Medulla Oblongata – know this!
Continuation of spinal cord
Functions
• Maintains wakefulness and alertness
• Contains reflex centers
–Cardiac center, vasomotor center,
respiratory rythmicity center
–Other nonvital centers
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Neural Imaging 1: EEG – know what it is
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Human Anatomy, 3rd edition
Prentice Hall, © 2001
EEG
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Applications of EEC Feedback - example
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Neural Imaging – 2: Brain CT Scan – know what it is
• Developed in 1970s (Nobel prize 1979)
• Noninvasive; a radio-opaque contrast dye is usually injected
intravenously
• CAT (or CT) scanning is a process that combines many 2dimensional x-ray images to generate cross-sections or 3dimensional images of internal organs and body structures
(including the brain).
• Doing a CAT scan involves putting the subject in a special,
donut-shaped x-ray machine that moves around the person
and takes many x-rays. Then, a computer combines the 2dimensional x-ray images to make the cross-sections or 3dimensional images.
• CAT scans of the brain can detect brain damage and also
highlight local changes in cerebral blood flow (a measure of
Human Anatomy, 3rd edition
brain activity) as the subjects
perform
a task.
Prentice Hall,
© 2001
Brain CT Scan
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Neural Imaging – 3: Brain MRI
• Magnetic Resonance Imaging: Magnetic resonance imaging utilizes radiowaves.
– Radiowaves have far less energy than x-rays
Human Anatomy, 3rd edition
Prentice Hall, © 2001
MRI – know what it is
• A MRI scanner has a large
and very strong magnet.
• A radio wave antenna is
used to send radio wave
signals to the body and then
receive signals back.
• These returning signals are
converted into pictures by a
computer attached to the
scanner.
Human Anatomy,
3rd edition
Prentice Hall, © 2001
•
This image set is comparing a young individual (left) with an athletic male
in his 80's (center) and with a person of similar age having Alzheimer's
Disease (right),
all imaged
at the same level.
Human Anatomy,
3rd edition
Prentice Hall, © 2001
MRI Images: Multiple Scelerosis - example
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Normal Brain MRI: Playing the piano - example
Human Anatomy, 3rd edition
Prentice Hall, © 2001
Neural Imaging –SPECT/PET
SPECT/PET (single photon/positron emission computed
tomography)
• When radiolabeled compounds are injected in tracer amounts,
their photon emissions can be detected much like x-rays in CT.
• The images made represent the
accumulation of the labeled
compound. The compound may
reflect, for example, blood flow,
oxygen or glucose metabolism,
or dopamine transporter concentration.
• Often these images are shown with a
Human Anatomy, 3rd edition
color scale.
Prentice Hall, © 2001
PET scan of the brain for Alzheimer's disease
These PET scan images show normal brain activity (left) and reduced brain activity caused
by Alzheimer's disease (right). The diminishing of the intense white and yellow areas in
the image on the right indicates mild
Alzheimer's
Human
Anatomy, 3rddisease,
edition with the increase of blue and
green colors showing decreased brainPrentice
activity.
Hall, © 2001