Download The Cerebrum - MrOwdijWiki

The Cerebrum
The Cerebrum
• When you think of the brain, you
think of the cerebrum
• This is the highly visible
structure that resides on the
outside of the brain
• Its specialization makes humans
different than every other
species on the planet
The Cerebrum
• The cerebrum is the largest part
of the brain
• It contains the areas that give
you the ability to have conscious
thought
• The surface of the brain is
covered in cerebral cortex that is
amongst the most advanced
parts of the human body
The Cerebrum
• On the surface of the cerebral
cortex there are bends and folds
• These bends and folds are
referred to as the gyrus of the
brain
• The many gyri have the function
of increasing the surface area of
the brain and allowing for more
neurons
The Cerebrum
• The cerebrum continues to grow
and develop along with you until
the age of 20 – 25
• During this time, there are
important growth benchmarks,
developmental landmarks and
neural connections that are
made
• Damage to the brain before it
fully develops can lead to
disastrous results
Video
• http://www.abc.net.au/btn/stor
y/s4085947.htm
• Ever wonder why the drinking
age is 21?
Lobes
• The cerebrum can be divided up
in several different ways
• One way to divide it up is in the
“lobes” or sections of the brain
• These lobes each have a
different functions and are
responsible for different parts of
the body
Lobes
• There are four lobes to the brain
• They relate to the bones on the
skull (if you remember them…)
• The frontal lobe
• The parietal lobe
• The temporal lobe
• The occipital lobe
Lobes
• The frontal lobe is located in the
ventral part of the brain
• The frontal lobes are involved in
motor function, problem solving,
spontaneity, memory, language,
initiation, judgement, impulse
control, and social and sexual
behavior
• It is the thing that makes you…
you
Frontal Lobes
• https://www.youtube.com/watc
h?v=rIX5YTPtKCs
Lobes
• The parietal lobe is located
dorsal the frontal lobe and it is
still superior to the occipital lobe
• The parietal lobe is responsible
for sensation and perception
and the other is concerned with
integrating sensory input,
primarily with the visual system
• It is an important lobe with the
Lobe
• The temporal lobe is located
inferior to the frontal and parietal
lobe but ventral to the occipital lobe
• It is involved with
auditory perception, such as
hearing and holds the primary
auditory cortex. The primary
auditory cortex receives sensory
information from the ears and
secondary areas process the
information into meaningful units
such as speech and words
• It also has a variety of other
functions including
Video
• http://www.cbsnews.com/news/fa
ce-blindness-when-everyone-is-astranger-20-03-2012/
• Interesting
• Region affected by face blindness
Lobe
• The occipital lobe is located
dorsal and inferior to the other
lobes of the brain
• The occipital lobe is the major
visual processing area of the
brain
• It is tasked with finding visual
patterns and similarities in the
brain
Demo
White Matter
• Lets play a game show!
• First trivia question…
• What is the major structural
difference between grey and
white matter?
• Answer…
• White matter has myelin
insulating its axons
• Ok… too easy!
• Second trivia question…
• What is the major functionality
difference between grey and
white matter?
• Answer…
• Grey matter for information
processing and white matter for
information transport and signal
propagation
White Matter
• The interior of the cerebrum
consists mostly of white matter
• These axons can be classified in
one of three ways
• Association fibers interconnect
areas of cerebral cortex within
their hemisphere
• Commissural fibers allow
information transfer between
hemispheres (corpus callosum)
• Projection fibers link the cerebral
cortex to the diencephalon, brain
stem, cerebellum and spinal cord
Basal Nuclei
• Your cerebrum has two modes that
run stimulatingly
• It is very similar to how your
computer operates
• Your cerebrum can run conscious
and unconscious functions at the
same time
• In a similar way your computer will
run a visual program (google
chrome) and background programs
(antivirus programs, music, blue
tooth, firewalls, etc)
Basal Nuclei
• The sections of the cerebrum
that handle unconscious
processing are the basal nuclei
• The basal nuclei are grey matter
neurons of the cerebrum that
are located within the floor of
the lateral ventricle
• The have been associated with
the midbrain and the
diencephalon to handle larger
subconscious processing
Basal Nuclei
• The basal nuclei are in control of
many unconscious functions
• These include…
• Skeletal muscle tone
• Coordination of learned
movements
• Patterns and rhythms of
movement
Basal Nuclei
• Activity of the basal nuclei is
inhibited by structures in the
midbrain
• These sections of the midbrain
release dopamine, which inhibit
the functions of the basal nuclei
• When the cells in the midbrain are
damaged, they release less
dopamine and they have less
control over the basal nuclei
• This scenario give the basic
symptoms of Parkinson’s disease
Video
• http://abcnews.go.com/Health/
video/dr-oliver-sacks-real-lifeawakenings-29088197
• Amazing real life differences
• https://www.youtube.com/watc
h?v=pCONDfjm25s
Motor and Sensory Areas
• There are several major motor
and sensory areas within the
cerebral cortex
• These are areas of the cerebral
cortex that are specifically
designed to handle sensory
information coming in and what
information should be going out
Motor and Sensory Areas
• The primary motor cortex is
located within the boarders of
the frontal lobe
• This is the primary site of
voluntary movement of skeletal
muscles from the feet to the
face
• This creates a thin band that is
responsible for a wide variety of
motor control
Motor and Sensory Areas
• The primary sensory cortex is
located within the parietal lobe
• This structure coordinates all of
the conscious perceptions of
touch, pressure, pain, vibration,
taste and temperature
• Most of the things that you feel
are a combination of those
sensations mixing in this area
Motor and Sensory Areas
• The occipital lobe is home to the
visual cortex
• The visual cortex is responsible
for all conscious visual
interpretation and coordination
of stimuli
• This section of the brain is a
comparatively large percentage
of the brain
Motor and Sensory Areas
• The auditory cortex and the
olfactory cortex areas are found
in the temporal lobe
• The auditory cortex is used to
interpret and coordinate sounds
in the brain
• The olfactory cortex is used to
recognize, store and coordinate
smells
Motor and Sensory Areas
• Association areas are found
throughout the brain in the
cerebral cortex
• They are connected to the motor
and sensory areas of the
cerebral cortex and help with
taking the gathered information
and creating a neural response
• Many times the response will be
a motor response
Prefrontal Cortex
• There are areas in the brain that
communicate with multiple
association areas
• These areas of the brain are
designed to direct extremely
complex motor activities that
are tied into sensory functions
• These areas are called
integrative centers
Prefrontal Cortex
• Integrative centers are located
within each lobe of the brain and
they will link association areas
• As an example the prefrontal
cortex of the frontal lobe takes in
sensory information relayed to the
association areas
• The prefrontal cortex then makes
judgements such as predicting the
outcomes of possible motor
functions
Video
• https://www.youtube.com/watc
h?v=u76jBk59RFk
• When in doubt… relate things to
the Big Bang Theory…
• “Questionable” themes are used
to demonstrate a point
Prefrontal Cortex
• Since the prefrontal cortex is so
important for the human
experience, things can go wrong
when it is not working properly
• Lack of experience to provide
systems of analysis lead some
people to make poor judgements
• Damage to the prefrontal cortex
through injury generally leads to
temporary or permanent inability
to understanding time
relationships and judgements in
outcome
Prefrontal Cortex
• Since the prefrontal cortex is
connected to so many other areas
it has been linked to feelings of
tension, anxiety and frustration
when not working properly
• When this happens during a long
term period, many people used to
receive a prefrontal lobotomy
• This would damage the prefrontal
cortex and change brain function
• While it was effective to change
previous stressful feelings, it also
changed other judgement based
actions such as tact, taste and
when/where to use the bathroom
Video
• https://www.youtube.com/watc
h?v=_0aNILW6ILk
• Science does not always get it
right…
Other Integration Areas
• There are many other integration
areas in the brain
• The general interpretive area is
called the Wernicke’s area
• This area receives information from
all of the sensory information areas
• Damage to this area changes the
ability to connect pieces of sensory
information
• A patient might understand the
words “sit” and “here” but would
be unable to comprehend the
phrase “sit here”
Other Integration Areas
• Some of the nerves in the general
interpretive area enervate the speech
center called the Broca’s area
• This area regulates the patterns of
breathing and vocalization needed to
have a conversation
• Damage to this area results in aphasia,
or the wide variety of disorders with
an inability to correctly vocalize
• Since is is so closely related to the
general interpretive area, it can affect
speech, reading and writing
Video
• https://www.youtube.com/watc
h?v=dKTdMV6cOZw
• Can understand, cannot
correctly communicate