What is included in the CNS?
(central nervous system)
Brain and spinal cord
What is included in the PNS?
(peripheral nervous system)
The rest of the nerves
What are the two main cells of the nervous system?
Glia and Neurons
What are glia cells?
Support cells; serve and protect by cautioning and keeping neurons in position
What are neurons?
Carries information with electrical and chemical signals
What are the main building blocks of neurons?
- cell body (Stoma)
- dendrites
- axons
- terminal buttons
- myelin
What is the stoma?
the cell body which has the machinery to keep the neuron alive
What are dendrites?
receives info; listens and protects
the trees
What is an axon?
transmits input and at its end is the terminal button; varies in size from a mm to a m
What is a terminal button?
source of communication
What is the myelin?
The fatty insulation that protects the neuron
The neuron communicates through what?
nerve impulses
There is fluid inside and outside of the neuron containing what?
Charged particles
When the neuron is at rest, what are the charges inside and outside the cell?
The inside has a (-) negative charge compared to the outside.
What is resting potential?
stored energy
What is action potential?
the action potential is when there is an electrical shift occuring down the axon in a wave, to send a message
When a neuron is at rest what is the voltage?
-70 mV
What is the stimulus threshold and its value?
The amount the voltage needs to increase for the neuron to fire; needs to increase to -60 mV
What are some principles of action potential?
- all or nothing law
- once triggered AP travels down to the end of the neuron
- travels in only one direction
Where is the point of communication between neurones?
synapse
What are terminal buttons?
the sacs that carry neurotransmitters to the end of the pre synapse
What is the synaptic cleft?
the space btw the pre synapse and the post synapse
Where are the lock and key (receptor sites) of the synapse found?
post synapse
What happens when the neurotransmitters attach to the post synapse?
There is postsynaptic potential (from a small charge being created), which changes the probability of the next neuron firing
What is excitatory post synapse potential (PSP)?
temporary depolarization of postsynaptic membrane potential caused by the flow of positively charged ions into the postsynaptic cell as a result of opening of ligand-gated ion channels.
What does Inhibitory PSP do?
makes the post synaptic neuron less likely to generate action potential
Neurotransmitters are recycled via what process?
reuptake (the process of enzymes breaking down neurotransmitters
What is GABA?
GABA is a chemical messenger that is widely distributed in the brain. GABA’s natural function is to reduce the activity of the neurons to which it binds.
inhibitor effect; relates to anxiety and motor control
Drugs that increase GABA activity are called what?
agonistic (increase binding)
What is dopamine?
Dopamine is a neurotransmitter that helps control the brain’s reward and pleasure centers
What two disorders are associated with dopamine?
Parkenson’s (they lose muscle control due to cells that produce dopamine dying off
Schizophrenia (treated with antagonist because they have too much dopamine)
What is tardine a side effect of?
Antagonistic drugs of dopamine
What is serotonin associated with?
sleep and mood; when there is not enough serotonin you become depressed; when you take drugs like ecstasy you make production of serotonin happen quickly and the cells get tired and with over use of the drug they will die off
Within the peripheral nervous system there are 2 main subgroups. Name them.
Somatic and automonic
Name the two subgroups of the autonomic nervous system.
Sympathetic and Parasympathetic
What are afferent nerves?
nerves in the peripheral nervous system responsible for taking sensory information to the CNS;
Afferent Approach CNS
What are Efferent Nerves?
nerves in the PNS that take messages from CNS via motor nerves;
Efferent Exit
What does the Somatic System do?
keeps CNS in contact with the external environment;
VOLENTARY (talks to skeletal muscle)
What does the Autonomic System do?
keeps CNS in touch with internal environment
AUTOMATIC/ INVOLUNTARY
What is the spinal cords main focus?
transmits messages btw PNS and the brain
Name the 3 main areas of the brain.
hindbrain, midbrain, forebrain
What do you find in the hind brain?
medulla (life functions lie circulation)
pons (active when dreaming)
cerebellum (balance and spacial skills)
What is found in the midbrain?
reticular formation (band of fibres that filter noise when sleeping)
What is the main function of the forebrain?
emotion and complex thought
What is found in the forebrain?
- thalamus
- hypothalamus
- hippocampus (controls memory); part of limbic system
- amygdala (basic function, when damaged reactions become overblown);part of limbic system
- cerebral cortex
What does the hippocampus do?
controls memory
What does the amygdala do?
controls basic functions
What does the thalamus do?
sensory perception regarding motor function
What does the hypothalamus do?
links nervous system to endocrine system; controls autonomic function
Where is grey matter found?
cerebral cortex
Name the 4 lobes of the brain.
occipital (eyes)
parietal (visual spatial)
temporal (auditory)
frontal (movement)
Whats the main function of the occipital lobe?
eyes
What is the main function of the parietal lobe?
visual spatial
What is the main function of the temporal lobe?
auditory
What is the main function of the frontal lobe?
movement
What is the prefrontal portion of the brain responsible for and why is it special?
higher function; special because its only found in humans
What does contralateral control refer to?
Right side of brain controls left side of body and vice versa.