Transcript Neuroscience

Neuroscience
Chapter 2
I. Parts of the Brain
A. The Lobes – divide the brain into 4 major sections by
fissures
1.
Frontal Lobe – area of the brain associated with higher
mental abilities, movement, personality and the sense of
smell
 Contains the Motor Strip – portion of the brain that
controls body movement – can be stimulated through electrical
impulse
 Importance to the body denotes designation of space in the MS
 Frontal Association Area
 Interprets & evaluates your environment – what is going on,
what to feel, makes sense of things going on around you
 Size reflects intelligence
 Damage to this portion can create serious problems with a
persons personality (inappropriate emotions, socially
unacceptable behavior, fewer inhibitions, failure to make longterm plans, easily distracted, difficulty understanding a string of
facts or events)
The Lobes Cont.
1. Parietal Lobe – Portion of the brain where
body sensations register (touch, temperature,
pressure etc)
 Contains the Sensory Strip – provides and
registers sensation
2. Occipital Lobes – responsible for processing and
interpreting visual information
 When damaged it effects what and how well a person
can see
3. Temporal Lobe – contains centers for hearing
and some language functions
B. The Hemispheres
• Hemispheres – The sides of the brain divided by a
large lengthwise fissure, both hemispheres work
together on most tasks
• Corpus Callosum – connects and allows for
communication between the right and left hemisphere
▫ When this is cut most communication between the 2
halves is cut off
• Dominance – this is the side of the brain that is
preferred over the other
▫ The hemisphere that is dominant controls most
actions and fine motor skills
▫ If you are left handed you are right brain dominant etc
Hemispheres cont.
• Left Hemisphere Tasks – local view
▫ Handles verbal and speech material, like encoding and syntax
some logic and writing, superior at judging time, math, rhythm &
coordinating complex movements like those associated with
speech
▫ Mainly involved in analysis and processing information
sequentially
• Right Hemisphere Tasks – global view
▫ Can produce only basic speech and numbers
▫ Deals with objects in space, recognizing patterns, faces, and
melodies, putting together a puzzle and drawing a picture, some
mathematical reasoning
▫ Helps express emotions and detect emotions of others
▫ Chances are these people will be better at nonverbal activities,
specializes in imagery
▫ Processes material simultaneously and holistically
C. The Cerebrum and the Cerebral
Cortex
1. The outermost layer of the brain – the gray matter
2. Includes hemispheres, lobes and the frontal
association area
3. Controls very high-level thought and takes up
2/3rds of the brains nerve cells (100 billion)
4. Responsible for voluntary movements, sensations,
learning, remembering, consciousness etc.
5. Corticalization – the increase in the size and
wrinkles of the brain
▫ small correlation between brain size and
intelligence (not between humans & humans but
humans and other animals)
D. The Lower Brain
1.
2.
3.
▫
▫
The Lower Brain - communicates back and forth with the
cerebral cortex for non-automatic human responses
The Thalamus – acts as a sensory relay station sending
and receiving information to other parts of the brain
(vision, hearing, taste & touch) damage can cause
blindness, deafness, etc (not smell)
The Cerebellum – primarily regulates posture, muscle
tone & muscular coordination
Stores memories related to skills and habits (class
schedules, driving directions)
Damage – walking, running, playing catch are impossible,
area of the brain where degenerative diseases effect
coordinated motor function
The Lower Brain Cont.
4. The Hypothalamus – control center for emotions
and basic motives - helps control rage, pleasure,
hunger and sexual desire, temperature control
5. Reticular Activating System – works to catch
nerve impulses from the brain to the body and back
▫ Affects your alertness, sorts & prioritizes nerve
impulses, controls reflexes involved in breathing,
sneezing, coughing, and vomiting, and affects muscle
tone, posture, and movement of the head, eyes, face &
body
▫ Bombards the cortex with stimulation keeping it active
and alert
II. Brain
Communication
A. Neuron – the nerve cell of the
brain
1. Dendrite – short fibers that act
as receptors, receiving messages
from other nerve cells
2. Axon – longer fiber that carries
messages from the cell to other
neurons
B. Synapse – space between the
axon of one neuron and the
dendrite of another neuron
1. Vesicle – bubble like containers
that hold chemical molecules
called neurotransmitters
Brain Communication cont.
C. Neurotransmitters – send messages over the
synapse to the dendrite receptor
1. Acetylcholine – type of neurotransmitter that
affects body movements (food poisoning)
2. Dopamine – neurotransmitters involved in the
control of body movements (Parkinson’s
disease)
3. Endorphins – neurotransmitter that relieves
pain and increases your sense of well-being
(ecstasy & other drugs)
C. The Spinal Cord
1. The neurons in the spinal cord are short, direct
and powerful.
2. have few synapses – shorter time for
information to be received and an action to
occur
3. reflex – activation of the muscle(s) before the
message is received by the brain (dropping a
baby)
III. The Endocrine System
• The Pituitary Gland – small bean shaped gland attached to
and controlled by the hypothalamus
▫ Responsible for sending messages to other glands to activate
them
▫ Responsible for determining the height of the person
▫ The gland creates a growth hormone which appears in the
body’s system sporadically resulting in on and off growth
spurts
▫ Can be effected by the environment and diet of the
individual
• Thyroid Gland – located in the neck this gland controls a
persons metabolism
▫ This affects the rate a which a person’s body operate, inactive
thyroid = a sluggish person, a overactive thyroid = jumpy and
hyper person
III. The Endocrine System cont.
• The Adrenal Gland – located on the right and left
side of the body above the kidneys
▫ Responsible for putting adrenaline in to the
bloodstream
 Affects us by increasing breathing, blood pressure,
muscles tension & energy level
▫ Will also release a chemical that allows for the
faster clotting of blood
▫ This happens during testing or any other high
anxiety time (fight or flight reaction)
 TIP: to decrease test anxiety force yourself to take slow
deep breaths, this will stimulate brain activity instead of
shutting it down to prepare for an emergency
III. The Endocrine System cont.
• The Gonads – sex glands located in the testis in males
and the ovaries in females
▫ Androgen – the male hormone that stimulates the
growth of hair, the deepening of the voice and the
production of sperm
 Starts the sex drive of both males and females
 Sex drive is taken over by the cortex which allows us to
associate other emotions like love and caring with the act of
intercourse
▫ Estrogen – the female hormone that causes the
production of eggs the enlargement of the mammary
glands and the menstrual cycle to begin
 Both of these hormones are produced in the gonads and
released during the middle teenage years
IV. The Nervous System
▫ The nervous system is our body’s electro-chemical
information network (interstate highway)
• Central Nervous system – includes our brain
and spinal cord
• Peripheral Nervous system – links the CNS with
the body’s sense receptors, muscles and glands.
▫ Axons – are grouped & bundled as cables that
shoot messages back and forth along our nerves
Types of Neurons
• Sensory neurons - gather and send info to the
CNS
• Motor Neurons – sends messages from the CNS
to the body’s tissues and muscles
• Inter Neurons – communicate between the
sensory neurons and motor neurons
Peripheral Nervous System
• Somatic Nervous System -
• Autonomatic Nervous System –
▫ Sympathetic –
▫ Parasympathetic -