Summary of Brain Organization Flashcards
THE NERVOUS SYSTEM IS NOTHING TO BE NERVOUS ABOUT, YOU GOT THIS
What are the 4 main parts of the BRAIN?
1) CEREBRUM
2) DIANCEPHALON
3) BRAINSTEM
4) CEREBELLUM
What are the 2 hemispheres of the CEREBRUM?
1) Left hemisphere
2) Right hemisphere
What are the 5 lobes of the CEREBRUM?
1) FRONTAL LOBE
2) PARIETAL LOBE
3) OCCIPITAL LOBE
4) TEMPORAL LOBE
5) INSULA (can’t be seen from the outside)
What are the 3 layers of the CEREBRUM?
1) CEREBRAL CORTEX
2) WHITE MATTER
3) BASAL NUCLEI
What are the 3 parts of the DIANCEPHALON?
1) THALAMUS
2) HYPOTHALAMUS
3) EPITHALAMUS
What are the 3 parts of the BRAINSTEM?
1) MIDBRAIN
2) PONS
3) MEDULLA OBLONGATA
How can the CEREBRUM be divided?
In half, into lobes, or into 3 layers
What does the left hemisphere of the CEREBRUM mainly control?
It controls the movement of the right side of the body, and more academic things such as language, math, logic, speech, etc.
What does the right hemisphere of the CEREBRUM control?
it controls the movement of the left side of the body, and more “fluffy” things such as creativity, intuition, emotion, artistic ability, etc.
What does the term “controlateral control” mean?
It means that the right hemi controls the left side of the body and vice versa
What is the fissure dividing the 2 hemi’s called?
The LONGITUDINAL FISSURE
What are the grooves in the surface of the CEREBRUM called?
SULCUS (s) or SULCI (pl)
What are the ridges in the surface of the CEREBRUM called?
GYRUS (s) or GYRI (pl)
What is the function of the LATERAL SULCUS?
It outlines the TEMPORAL LOBE
What is the function of the CENTRAL SULCUS?
It separates the FRONTAL and PARIETAL LOBES
What is the function of the TRANSVERSE FISSURE?
It separates the CEREBRUM and the CEREBELLUM
What is the CEREBRAL CORTEX made of? Approximately how thick is it?
SUPERFICIAL GREY MATTER - DENDRITES, SOMA, UNMYELINATED AXONS. 2-4 mm thick
What part of the BRAIN make up 40% of total BRAIN mass?
The CEREBRAL CORTEX
Which part of the CEREBRAL CORTEX is responsible for hearing?
Haven’t ya heard? It’s the PRIMARY AUDITORY CORTEX
What does the AUDITORY ASSOCIATION AREA in the CEREBRAL CORTEX do?
It is responsible for integrating info, understanding what we’re hearing.
What is the role of the PRIMARY MOTOR CORTEX? Where is it found?
It controls precise voluntary movement and is found in the PRECENTRAL GYRUS
What is the role of the PREMOTOR CORTEX (also known as the MOTOR ASSOCIATION AREA)?
It controls learned/patterned skills
e.g. typing, dancing, speaking
What is the role of the PREFRONTAL CORTEX?
It controls intellect, personality, complex learning, planning, judgement, reasoning, analysis (it develops slowly)
What is the role of the BROCA’S AREA?
It plans and programs MOTOR CORTEX for speech
What is the role of the PRIMARY SOMATOSENSORY CORTEX? Where is it found?
It receives info from skin and muscle, can identify regions of the body that are stimulated, most sensitive area = largest area of CORTEX. Located in the POSTCENTRAL GYRUS
What is the role of the SOMATOSENSORY ASSOCIATION AREA?
It integrates sensory input and gives understanding
e.g. knowing the difference between coins and your keys by just touch
What is the role of the PRIMARY VISUAL CORTEX?
It receives visual info
What is the role of the VISUAL ASSOCIATION AREA?
It integrates color, form, movement, etc. also recognition and understanding what youre seeing
What is the role of WERNICKE’S AREA?
It interprets the meaning of speech
Name 3 types of myelinated fibers in large tracts
1) ASSOCIATION FIBERS
2) COMMISSURAL FIBERS
3) PROJECTION FIBERS
Which type of WHITE MATTER connects different parts of the same hemisphere?
ASSOCIATION FIBERS
Which type of WHITE MATTER connects corresponding areas of 2 hemispheres? (the largest = the CORPUS CALLOSUM)
COMMISSURAL FIBERS
Which type of WHITE MATTER connects the CORTEX to the rest of the nervous system? (runs vertically)
PROJECTION FIBERS
Explain BASAL NUCLEI
They are a collection of nerve cell bodies and they influence motor control
e.g. starting, stopping, intensity
Where is the DIANCEPHALON (aka “head of the seahorse” found?
Its found deep to the CEREBRAL HEMISPHERES
What does the THALAMUS (aka the main head of the seahorse” do?
- It receives all sensory info (integrate, filters in, and relays some to the CORTEX)
- general feeling of (un)pleasantness
- mediates sensation, motor activities, learning, memory
The HYPOTHALAMUS (aka “snout of the seahorse”) detects, then activates mechanisms that regulate:
- ANS (cardiac and smooth muscle, glands)
- Emotions (fear, anger, pleasure, sex drive, etc.)
- Body temp. (sweating and shivering)
- Food intake (feelings of hunger or satiety)
- Water balance (thirst, water retention)
- Sleep/wake cycles
- Endocrine system (produce hormones and control secretion of other hormones
What is the function of the EPITHALAMUS (aka “mane of the seahorse)?
contains the
- CHOROID PLEXUS = capillary network involved in CSF formation
- PINEAL GLAND = small endocrine gland that secretes melatonin which regulates sleep cycle and mood.
What is the CORPORA QUADRIGEMINA?
It is 4 raised bodies on the dorsal surface of the MIDBRAIN
What reflexes does the SUPERIOR COLLICULI control?
It controls visual reflexes
e.g. tracking a moving object
What reflexes does the INFERIOR COLLICULI control?
it controls auditory reflexes
e.g. being startled by something, jump scares, etc.
What does the MIDBRAIN do?
- (WHITE) it coordinates and relays info between CEREBRUM and CEREBELLUM
- (GREY) substantia nigra - inhibits THALAMUS and BASAL NUCLEI to prevent unwanted movement (degeneration of neurons = Parkinson’s tremors
What does the PONS (aka the “belly of the seahorse” do?
- (WHITE) connects CEREBELLUM to the rest of the CNS
- (GREY) respiratory centers - controls and modifies breathing rhythms
What does the MEDULLA OBLONGATA (aka “tail of the seahorse” do?
Be prepared…its a lot…
- Blends into SPINAL CORD
- Relays and integrates sensory info from ascending tracts
- motor tracts relay commands
- decussation of the pyramids = 85% of tracts
cross over here
- allows contralateral control - autonomic reflex centers
- cardiovascular center - regulates force of
contraction and BP
- respiratory rhythm center - sets rate and depth
of breathing
- other centers e.g. vomiting, sneezing,
swallowing, coughing
