Chapter 3 Flashcards
The communication between neurons is primarily?
Chemical
What did Charles Sherrington demonstrate?
Communication between one neuron and the next differs from communication along single axon
What are muscular responses to stimuli?
Reflexes
What are the three things Sherrington found out about studying reflexes with dogs?
Reflexes are slower than conduction along axon
several weak stimuli presented slightly different times of different locations produce stronger reflex
when one set of muscles becomes excited, a different set becomes relaxed
Sherrington deduced that transmission at a synapse must be slower than conduction along an axon. Based on
The speed of reflexive responses
What is temporal summation?
Repeating stimuli within a brief time have a cumulative effect
Postsynaptic means?
the cell that receives a message
Presynaptic means?
cell that delivers the transmission
What is the name of the potential that occurs when sodium ions enter the cell also known as depolarization?
Excitatory postsynaptic potential (EPSP)
What is spatial summation?
Synaptic inputs from various locations combine their effects on a neuron
What would produce a greater spatial summation?
Present two or more weak stimuli at the same time
What is the correct order of sequence of chemical events at a synapse?
synthesis,transport, release, reuptake
How might temporal summation occur?
neuron might receive input from several axons but not exactly at the same time.
axons active in one order can have different results from the same axons in different order
An IPSP represents?
temporary hyperpolarization
What does the IPSP potential do?
Occurs when the synaptic input selectively opens in the channel for potassium ions to leave the cell or for chloride ions to enter
What did T.R. Elliot suggest?
Synapses operated by using chemicals as means of transmitting signals
Which of the following actions is most likely to be dependent on ionotropic effects
Rapid muscle contraction
Which of the following is not a catecholamine?
Serotonin
The brain area most often linked to drug addiction?
Nucleus accumbens
The key into a lock analogy
drug’s affinity for a receptor
What effect do opiate drugs have on dopamine?
They indirectly increase the release of dopamine by blocking transmitters that normally block dopamine
Which type of alcoholism has a stronger genetic basis?
Type II
What are ionotropic effects?
Begin quickly and last for a very brief period
What are metabotropic effects?
slower and longer lasting
Why does a neuron release a combination of neurotransmitters instead of just one?
The combination makes the neuron’s more complex such as brief excitation followed by slightly but prolonged inhibition
What detects the amount of neurotransmitters released and inhibit further synthesis and release after it reaches a certain level
autoreceptors
