Cellular Synaptic Integration

Question 1

What are the 3 types of neurons?

Answer 1

Sensory, relay(interneuron), motor

Question 2

What is the most common neuron?

Answer 2

relay/interneuron

Question 3

What is neural computation?

Answer 3

the transformation of many synaptic inputs to a single neuronal output

Question 4

What is the lowest threshold for action potential?

Answer 4

-55 mV

Question 5

What is PSP?

Answer 5

“Postsynaptic potential”; it is a local graded potential on the postsynaptic cell

Question 6

How do PSP cause AP?

Answer 6

PSP travels from the site synapse to the axon hillock. If it hasn’t degraded too much, it will trigger an AP

Question 7

What are the 4 different types of synaptic integration?

Answer 7

1. Spatial
2. Temporal
3. Nature of postsynaptic potential
4. Coding

Question 8

What is spatial integration?

Answer 8

Adding together of synaptic inputs simultaneously occurring at different locations

Question 9

How does length constant affect decay over length?

Answer 9

the larger the length constant the less decay over length and therefore the greater chance for two or more synaptic potentials to summate

Question 10

What is temporal integration?

Answer 10

adding together of inputs occurring at different times, usually within 5-15 msec of one another.

Question 11

How does time constant affect decay over time?

Answer 11

The larger the time constant, the less decay over time and greater chance for summation.

Question 12

What are the diffferent natures of synaptic potential?

Answer 12

EPSP and IPSP

Question 13

What is EPSP?

Answer 13

excitatory postsynaptic potential; excitatory neurotransmitters that increase Na permeability resulting in depolarization

Question 14

What is IPSP?

Answer 14

inhibitory postsynaptic potential; inhibitory neurotransmitters increase Cl permeability resulting in hyperpolarization

Question 15

What causes muscle reflex?

Answer 15

EPSP contracts quadriceps; IPSP inhibits hamstring

Question 16

What is the reversal potential?

Answer 16

A point where no net current goes through the receptor.

Question 17

Where does EPSP occur in relation to reversal potential?

Answer 17

EPSP occurs below reversal potential

Question 18

Where does IPSP occur in relation to reversal potential?

Answer 18

IPSP occurs above reversal potential

Question 19

Synapse on dendrites are often ____

Answer 19

excitatory

Question 20

Synapse on cell bodies are often ____

Answer 20

inhibitory

Question 21

What does information coding rely on?

Answer 21

1. Place coding
2. Intensity coding
3. Input organization
4. Size principle

Question 22

What is place coding?

Answer 22

Looks at how the nervous system relies on topographic maps to keep information organized

Question 23

What is intensity coding?

Answer 23

Intensity coded by firing frequency

Question 24

What is input organization?

Answer 24

Surrounding inhibitory cells can maximize contrast and confine signal of interest to a smaller space

Question 25

What is size principle?

Answer 25

Looks at size of cells involved and size of target tissue; use differently size motor units for different tasks

Question 26

If you lift something heavy, would you use small motor neuron or large?

Answer 26

Large motor neurons innervate more muscle fibers and are activated with more tension