Flashcards in Chapter 3 Deck (16):
What is neurons ?
- Cells in the nervous system that communicate with one another to perform the information-processing tasks
- neurons are the basic building block of nervous system
- they receive and send electrochemical message
- All neurons have the same structure, but vary by function and by location in the nervous system
What is the component of neurons?
- Cell body: the largest part of the neuron that coordinate the information processing task and keep cells alive
- Dendrite: receive the information from others neuron and relay it to the cell body
- Axon: transfers information from others neuron, muscles or glands
What is axon covered with?
In many neurons, the axon is covered with myelin sheath. (an insulting of fatty material)
An axon insulted with myelin can more effectively transmit signals to other neurons, organ and muscles
- demyelinating diseases - myelin sheath deteriorates and transmissin is slowed
What is myelin sheath made up of ?
is composed of glial cells - support cells found in the nervous system
What does glial cells do ?
Glial cells can digest dead neurons, provide physical and nutritional support for neurons or form more myelin.
What is synapse ?
the junction or region between the axon of one neuron and the dendrites or cell body of another
Major types of neurons
sensory neuron: receive information from the external world and convey this information to brain via spinal cord
Specialize ending in the dendrites from receive signal from light, sound, touch taste and smell
Motor function: carry signal from spinal cord to muscles to provide movement
Interneurons: connect sensory neuron, motor function and other parts of interneurons
Mirror neurons are found in frontal and parietal lobe of many different animals
Activiate when animal performs a behavior or when it observes another animals performing a behavior
Important for understanding the brain role's in complex social behavior
Lacoboni et al
his study showed that mirror neurons response at the strongest when it observing actions that were embedded in a context
associated with impairments in the function of mirror neurons
types of interneuron that carries the information from cerebellum to brain via spinal coal
found in cerebral cortex that have triangular cells and one single long dendrite and many smaller dendrites
Information processing task
conduction of electrical signal over relatively long distance within neurons, from dendrites, to cell body and throughout axon.
Transmission of electrical signal between neurons over synapse
Together these stages are called electrochemical action of neurons
The resting potential
the difference in electrical charge between the inside and outside of neuron's cell membrane
the resting state arise from the difference of concentra tion of ions inside and outside the neuron's cell membrane
Ion can carry positive or negative charge
In a resting state, there is a high concentration of positively sodium ion and negative charged of chloride ion outside the neuron's cell membrane
There are also negatively charged protein ions inside the neuron's cell membrane compared to outside the neuron.
still in resting potential
Ion concentration is controlled by channels in the axon membrane that allow molecules to flow in and out of the neuron
In resting state, the potassium channels are opened wide while those that allow the flow of sodium are closed
the potassium ions leave the cell and sodium are kept out, thus in resulting a negative charge of -70mv relative to the outiside.