Transcript Hippocampus - Solon City Schools

The Brain
The Brain
• Made up of neurons
• 23 billion nerve cells
and 300 trillion
synapses
• Glial cells – support,
nourish (soma) and
protect interneurons
(provide insulating
myelin)
My husband is my glial cell.
He takes care of me!!!
Whose yours?
Ways we Study the Brain
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Accidents
Lesions
CAT Scan
PET Scan
MRI
Functional MRI
Accidents
Phineas Gage Story
• Personality changed
after the accident.
What this this tell us?
• That different part
of the brain control
different aspects of
who we are.
Lesions
• Removal or
destruction of
some part of the
brain.
• Frontal
Lobotomy
Electroencephalogram
• EEG
• Detects brain
waves through
their electrical
output.
• Used mainly in
sleep research.
Computerized Axial Tomography
• CAT Scan
• 3D X-Ray of
the brain.
• Quick views of
brain injury,
tissue damage
due to trauma
• Shows tumors
Magnetic Resonance Imaging
• MRI
• Uses magnetic
fields and radio
waves to produce
images of brain
structures
• Does not provide
info about how
actively the brain
in functioning
Positron Emission Tomography
• PET Scan
• Measures the concentration of glucose in
active areas of the brain
• Limited to monitoring short tasks
• Still pictures
Functional MRI
• Identifies most active areas of the brain
during a specific mental task
• Measures oxygen levels and blood flow to
the brain
• Structures and functions of the brain
Brain Structures
• Scientists divide the
brain up into three
parts.
• Brain Stem
• Limbic System
• Cerebral Cortex
Brain Regions
• Brainstem – medulla, pons,
reticular formation, thalamus,
cerebellum
• Limbic System – Hippocampus,
Amygdala, Hypothalamus
• Cerebral Cortex – frontal
lobe, parietal lobe, temporal
lobe, occipital lobe,
Brain Stem
• Part of the brain with the
oldest ancestry
• 5 Regions:
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Medulla
Pons
Reticular formation
Thalamus
Cerebellum
• Controls involuntary muscles
• Routes nerves from left side
of brain to the right side
Medulla Oblongata
• Brain’s Autopilot works with nervous
systems…. Autonomic
nervous system
• Controls:
Pons
• Acts as a bridge
between the brain
stem and cerebellum
• Involved in forming
facial expressions.
• Coordinates
functions between
left and right side
of brain
Cerebellum
• “little brain” attached near
brain stem
• Coordinates muscle
movements - Like tracking
a target.
• Controls balance
• Relies on visual information
to coordinate voluntary
movement
Reticular Formation
• Responsible for
arousal and ability
to focus
attention.
If stimulated
If destroyed
Thalamus
• Receives sensory information
and routes it to appropriate
areas of the brain. - all
sensory information accept
smell.
• Like a switchboard.
Limbic System
• EMOTIONAL
CONTROL CENTER
of the brain.
• Located between the
brainstem and
cerebral
hemispheres
• Made up of
Hypothalamus,
Amygdala and
Hippocampus.
Hypothalamus
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Controls the 4 F’s.
Fight (endocrine system)
Flight
Food (hunger & thirst)
Fornication (sex drive)
Endocrine System
– Pituitary Gland
• Maintains homeostasis
• Brain’s Reward system – what
neurotransmitter?
Hippocampus
• Hippocampus is
involved in memory
formation,
processing, and
storage.
Amygdala
• Amygdala is vital for
our basic emotions.
• Fear and Aggression
Cerebral Cortex
• Cerebral cortex - thin layer of
interconnected neural cells
• Glial cells
• Fissures – folds that increase
the surface area of the brain.
– Laid out it would be about the size
of a large pizza.
Areas of the Cerebral Cortex
• Divided into eight
lobes, four in each
hemisphere (frontal,
parietal, occipital and
temporal).
• Any area not dealing
with our senses or
muscle movements are
called association
areas.
Parietal Lobes
• Located at the top
of our head.
• Receives sensory
input for touch
Sensory Cortex
• Registers and
processes body
touch and movement
sensations
• More sensitive the
body region , the
larger the area
devoted to it
Frontal Lobe
• Planning,
• emotional control
• abstract thought,
logic,
• Moral Reasoning
• personality
development.
Motor Cortex
• Controls Muscle
Movement
• Body areas requiring
precise control
occupy the greatest
space
Temporal Lobes
• Process sound
sensed by ears.
• Receive info from
the opposite ear.
Occipital Lobes
• In the back of our
head.
• Handles visual input
from eyes.
• Right half of each
retina goes to left
occipital lobe and
vice versa.
Language Development
• Aphasia – impairment of language
• Frontal Lobe
– Broca’s Area – directs muscle movements involved in speech
• Temporal Lobe
– Wernicke’s Area – language comprehension and express
Hemispheres
• Divided into a left and
right hemisphere.
• Contralateral
controlled- left controls
right side of body and
vice versa.
• Brain Lateralization.
• Lefties are better at
spatial and creative
tasks.
• Righties are better at
logic.
Split-Brain Patients
• Corpus Collosum
attaches the two
hemispheres of
cerebral cortex.
• Removed in patients
with severe epilepsi
• When removed you
have a split-brain
patient.
Brain Plasticity
• The ability for our
brains to form new
connections after
the neurons are
damaged.
• The younger you are,
the more plastic
your brain is.