Neuro Flashcards
Pre-frontal cortex
Location and responsibilities
Located in the anterior frontal lobe.
Responsible for:
* Higher mental functions
* Goal oriented behavior
* Concentration
* Memory
* Elaboration of thought
Premotor cortex
Location and responsibilities
Located in frontal lobe
Responsible for:
* Programing motor movements
* Movements prior to signaling motor cortex (think before do).
Motor cortex
Location and responsibilities
Located in pre-central gyrus of frontal lobe
Responsible for:
* Voluntary motor
* Alpha motor neurons here
Somatosensory cortex
Location and responsibilities
Located in the post central gyrus of the parietal lobe
Responsible for:
* Distinct spacial organization
Each side of cortex recieves info from contralateral side of body
Brocas Area
Location and responsibilities
Located in the inferior frontal lobe
Responsible for:
* Muscles of speech
* Speech and language processing
* Motor output to form words
If you have dysfunction of Brocas area what type of aphasia will occur?
With explanation.
Expressive aphasia: individual cannot form words but can understand them.
Wernickes area
Location and responsibilities
Located in parietal lobe.
Responsible for:
* Reception
* Interpretion of speech
* Selecting words
What type of aphasia will be seen in an individual with damage to Wernickes area?
With explanation.
Receptive aphasia-Individual can speak but cannot understand words and uses illogical language.
Primary visual cortex
Location and responsibilities
Located in occipital lobe
Responsible for:
* Input from retina
* Visual association
Thalamus responsibilities
Relay station
Hypothalamus responsibilities
- Autonomic control: regulates vital functions.
- Produces oxytocin and antidiuretic hormone
What is the function of the basal ganglia?
- Motor plan from motor cortex will go to basal ganglia for refinement
- Starts, stops, odulates movement.
What does the direct path of the basal ganglia do?
- Induces movement
- Turns off tonic GABA release
What does the Indirect path of the basal ganglia do?
- Removes unwanted movement
- Persists tonic GABA release
Where does parkinsons originate from and why?
Originates in basal ganglia, GABA not inhibiting movement as it should.
Cerebellum responsibilities
Modify and coordinate movement
Where does the cerebellum recieve information from?
- Cerebral cortex
- Sensory systems
What are the brainstems responsibilities?
- Connects cerebrum with cerebellum and spinal cord
- Contains most of cranial nerve nuclei
- Respiratory drive
- Cardiovascular control
What does the gray matter contain?
- Cell bodies
- Dendrites
- Synapses
What does teh white matter contain?
Axons
What does the limbic system contain and what are its responsibilities?
Contains:
* Amygdala
* Hippocampus
* Hypothalamus
* Thalamus
Responsible for:
* Emotional well-being
* long term memory
What are the responsiblities of the blood brain barrier?
Protects flow of “stuff” into nervous tissue
Tight junctions permit some molecules through but not all
What is allowed to cross the BBB?
- Lipid soluble substances
- Water
- Some hormones
- Glucose
- Alcohol
- CO2
- Electrolytes
Explain the flow of CSF
1) CSF made by choroid plexus
2) Travels to lateral ventricles
3) Moves to third ventricle
4) Moves to fourth ventricle
5) Goes to subarachnoid space
6) Moves to superior sagittal sinus
7) Drains to veins
Extracellular fluid, plasma, and interstitial fluid are high in what?
Sodium
Nerve cells are most permeable to:
a) sodium
b) calcium
c) potassium
d) chloride
Potassium
Blood is a part of which fluid compartment?
a) Intracellular fluid
b) Interstitial fluid
c) Plasma
Plasma
Nerve cells are ____ (negative or positive) at rest. Why?
Negative due to the flow of potassium (While potassium is constantly leaking out, the cell is losing more sodium)
A neuron as rest has a resting potential of -70mV. You put this neuron in na solution where the concentration of potassium in the extracellular solution is higher. What happens to resting membrane potential?
It gets more positive (depolarizes)
With what disorders is hyperkalemia most commonly seen?
- Renal failure/ impaired kidney function
- Also presents with diabetic ketoacidosis
What is the point of an action potential?
To send a signal from one nerve to the next
Communication
Does hyperkalemia depolarize or hyperpolarize resting membrane potential?
Depolarizes
Does hypokalemia depolarize or hyperpolarize resting membrane potential?
Hyperpolarizes
What is a synapse?
A cell to cell junction
What are the steps in chemical transmission?
1) Presynaptic action potential
2) Voltage change in presynaptic neuron (depolarization) opens voltage gated calcium channels (Ca2+ flows in)
3) Calcium helps vesicles fuse with presynaptic membrain, neurotransmitter release
4) Neurotransmitters bind to receptor on post synaptic cell, causes response.
What makes a synapse inhibitory?
- Positive ion leaving the cell
- Negative ion coming into the cell
What makes a synapse excitatory?
- Positive ion coming in
- Negative ion leaving cell
Ionotropic receptor vs metabotrophic receptor
I: Fast, are a receptor and a channel.
M: Slower, recieve neurotransmitter, then require a 2nd messenger cascade that results in some downstream change.
Acetylcholine
function and excitatory, inhibitory, or both
- NMJ, cardiac rhythm
- Both
Dopamine
function and excitatory, inhibitory, or both
- Pleasure, learning, arousal, memory, addiction
- Both
Glutamate
function and excitatory, inhibitory, or both
- Addiction, neuroplasticity, learning
- Excitatory
Serotonin
function and excitatory, inhibitory, or both
- Mood, sleep, GI
- Both
Norepinephrine
function and excitatory, inhibitory, or both
- Vasoconstriction/vasodilation, fight or flight
- Excitatory
GABA
function and excitatory, inhibitory, or both
- Brain, CNS “inhibition”
- Inhibitory
Glycine
function and excitatory, inhibitory, or both
- Sensory, spinal cord and brainstem
- Inhibitory
Endorphins
function and excitatory, inhibitory, or both
- Fight or flight, analgesic
- Mostly inhibitory
Oligodendrocytes
Make myelin in the CNS
Schwann cells
Make myelin in the PNS
What is myelin?
- Lipid substance that insulates axons
- Allows for saltatory conduction
