Chapter 9 - Questions

Question 1

how long does the total refractory period last?

Answer 1

~1 msec

Question 2

what does the refractory period after a neural spike do?

Answer 2

limits the dumber of discharges possible for each nerve

Question 3

the neural firing rate is a useful indicator of:

Answer 3

neural activity

Question 4

the theoretical maximum neural firing rate is _____ spikes/sec but typical nerve fibers have a rate of less than ____

Answer 4

1,000; 500

Question 5

What is spontaneous activity and what is its discharge rate range?

Answer 5

neural activity that occurs without a stimulus; 0-100 spikes/sec

Question 6

How do we study nerve firings?

Answer 6

putting electrodes in the auditory nerve and recording the # of times it fires

Question 7

What is spontaneous rate?

Answer 7

The amount of times neural spikes occur even when there is no sound

Question 8

What does an input-output function show?

Answer 8

the increase in the discharge rate of a neuron (above the spontaneous rate) when the level of the acoustic stimulus is increased

Question 9

if the firing rate of the neuron goes up, we perceive that the sound is getting ________

Answer 9

louder

Question 10

how is the neuronal dynamic range determined?

Answer 10

subtract the saturation from the threshold

Question 11

what is a neurons possible neuronal dynamic range?

Answer 11

~20-50 dB

Question 12

low spontaneous firing rates have the _______ thresholds, and vice versa

Answer 12

highest

Question 13

A neuron can only increase its rate of firing in response to increasing intensity of a sound for son long, when it reaches its limit we call this ______________

Answer 13

saturation

Question 14

what is a single-neuron threshold

Answer 14

the minimum stimulus level that will cause an increase in the discharge rate (above the spontaneous rate)

Question 15

neurons with the highest spontaneous activity have the _________ thresholds

Answer 15

lowest

Question 16

stimuli of up to a frequency of ____-_____ Hz produce a ____/______-_______ response

Answer 16

4,000-5,000; time/phase-locked

Question 17

What is a phase-locked (or time-locked) response?

Answer 17

nerve firing locks with some phase of the stimulus, it may not fire on every cycle

Question 18

phase-lock response influences what two things?

Answer 18

1. absolute refractory period 2. pitch perception

Question 19

What is half-wave rectification?

Answer 19

A neuron only discharges to one direction of sound movement (hair cell shearing?)