Neuronal Mech. And Circ.

Front 1

1. What are the 3 overal fxns of the NS?
2. Arrange the A, B, and C nerve fiber types based on speed
3. What are the 4 subtypes of A fibers?
4. Which one of A, B, C is unmyelinated?

Back 1

1. Sensation (detection), Computation (integration), and Execution (response)
2. A>B>C
3. alpha > beta > gamma > delta
4. C, also the slowest

Front 2

1. What are 2 imp things that conduction velocity is correlated to?
2. What is the fxn of A alpha fibers?
3. What is the fxn of A beta fibers?
4. What is the fxn of A gamma fibers?

Back 2

1. Myelination and fiber diameter
2. Motor, skeletal m.
3. Sensory, touch, pressure vibration
4. Muscle spindle

Front 3

What is the fxn of:
1. A delta fibers
2. B fibers
3. C fibers

Back 3

1. Pain (sharp, localized), temp, touch
2. Preganglionic autonomic
3. Pain (diffuse, deep), temp, postganglionic autonomic

Front 4

1. Give the level of sensitivity to local anesthetics:
2. What is the easiest sensory modality to block?
3. What is a cmpd AP?

Back 4

1. Small myelinated axons > non-myelinated axons > Large myelinated axons
2. Pain sensation
3. One that arises from a variety of dif. size fibers

Front 5

1. When a cmpd AP is split up, what is the order of the individual AP?
2. Are all n. composed of the same fiber types?

Back 5

1. A alpha > A beta > A gamma > A delta > B > C in terms of speed
2. No, based on fxn, e.g. Muscle n has type A alpha and cutaneous n does not

Front 6

1. What is a pattern of n. impulses that transmits info?
2. What are two ways in which intensity of 1 can be coded?

Back 6

1. Signal
2. Spatial summation (# of n. fibers firing) and Temporal Summation (Frequency of AP)

Front 7

1. What is nerve convergence?
2. What is n. divergence?

Back 7

1. Multiple input n. feeding into a single output n.
2. Single input n splits into multiple output cells (1:8 ratio e.g.)

Front 8

Convergence vs divergence
1. Allows integration of information from different sources
2. Allows amplification of the initial signal plus splitting the signal so that the info is sent to multiple destinations

Back 8

1. Convergences (can be from many locations)
2. Divergence

Front 9

1. A type of self-regulation that limits the n. activity from exceeding some critical maximum. The extensor motor n. feeds back upon itself to modulate firing
2. It enhances the activity of the stimulated pathway by inhibiting the activity of antagonistic pathways. Modulates output activity plus focus the response

Back 9

1. Negative feedback inhibition
2. Feed-forward inhibition

Front 10

Name the inhibition:
1. Important in preventing over-stimulating self
2. If signal is sent to extensor, it promotes extension by inhibiting flexion, inhibits antagonistic pathways

Back 10

1. Negative feedback inhibition
2. Feed-forward inhibition

Front 11

1. inhibition of neighboring n. to enhance contrast of signal. Imp in visual system and in other sensory sys. w/ specific localization of the stimulus

Back 11

Lateral inhibition: excitation of 1 input neuron producing inhibition of adjacent neurons through inhibitory interneurons

Front 12

1. Modulates the effects of the input n. on the next n. in the pathway. Modulation may be from higher center descending pathways. In add., the modulation may be through peripheral receptor input

Back 12

1. Gating mechanism

Active- gate is open

Front 13

1. a mechanism whereby a single AP in the input n. may elicit a train of AP in the output n. The degree of discharge freq. will depend on the complexity of the circuit.
2. What is 1 imp in?

Back 13

1. Positive feedback Loops (reverberating circuits)
2. Short term memory

Front 14

1. term for NT depletion or inactivation of postsynaptic receptors
2. What is facilitation in a reverberating circuit?
3. put in order based on length of action, facilitated, inhibited and normal

Back 14

1. synaptic fatigue, decreases or abolishes activity of the circuit
2. There are additional interneurons involved in the process
3. Facilitated then normal then inhibited in length

Front 15

1. prolongation of discharge in the output neuron b/c input neuron stimulates multiple excitatory interneurons [like divergence then convergence on same pathway after 1 interneuron]

Back 15

1. After-discharge circuit (mb won't last as long as reverberating)

Front 16

1. Groups of n. whose discharge is continuous in a rhythmic fashion. Their rate can be increased or decreased by inputs. Examples are hr, rr

Back 16

1. Continuous discharge neurons

Front 17

1. What is the discharge zone of a neuronal pool?
2. What is the facilitated zone (subliminal fringe)?

Back 17

1. Where postsynaptic fibers r receiving enough input fibers to fire an output
2. receives smaller # of inputs, will only be brought to threshold by overlapping zones from different input fibers