Motor

Question 1

What is the population code?

Answer 1

Firing vector/pattern among a full ensemble of 50 or more neurons.

Question 2

What is the correlation coefficient?

Answer 2

The relationship between patterns and firing rates.

Question 3

When firing and correlation is high, patterns are ________.

Answer 3

Similar

Question 4

How many neurons need to fire in order for rate vectors to nicely distinguish conditions?

Answer 4

50 or more

Question 5

T/F: Firing rates are dependent on the firing of a grandmother cell.

Answer 5

False. This disproves the grandmother cell theory.

Question 6

T/F: Nitz is afraid of advancements in artificial intelligence.

Answer 6

False. Nitz is pro-artificial intelligence improvement.

Question 7

What are the two fibers of muscles?

Answer 7

Slow twitch and fast twitch

Question 8

How long does it take for slow twitch fibers to reach peak force?

Answer 8

STF: take 50 mS to reach peak force.

Question 9

How long does it take fast twitch fibers to reach peak force?

Answer 9

FTF: 25 mS to reach peak force, but fatigue quickly.

Question 10

Slow twitch fibers are used for…?

Answer 10

Tonic movements: maintaining posture.

Question 11

Fast twitch fibers are used for…?

Answer 11

Quick, powerful movements like sprinting and punching.

Question 12

The muscles along your spine are what kind of fiber?

Answer 12

Slow twitch

Question 13

Muscle fibers are driven by ________ ______ neurons.

Answer 13

Alpha motor neurons

Question 14

Where are alpha motor neurons found?

Answer 14

The ventral horn in the spinal cord

Question 15

Alpha motor neurons interface with fibers and release what neurotransmitter?

Answer 15

ACh

Question 16

Alpha motor neurons release ACh via…? (what kind of receptor)

Answer 16

Via nicotinic receptor: a fast ionotropic excitatory receptor

Question 17

A ________ ______ is defined as a pattern of co-activation of muscles recruited by a single neural command signal.

Answer 17

muscle syngergy

Question 18

Describe the muscles in your legs, in regards to the two phases of stepping.

Answer 18

There are 6 different muscles in the legs, which turn on and off as you step. At any given point, 3 muscles are active and 3 are inactive.

Question 19

Give an example of muscle synergy.

Answer 19

The knee-jerk example is a simple muscle synergy example. The inhibition of the hamstring muscle is driven by a muscle spindle afferent.

Question 20

Describe the connections of interneurons in the spinal cord.

Answer 20

Interneurons in the spinal cord can be interconnected with themselves as well as motor neurons.

Question 21

Interneuron axons can cross over to the ________, to other segments of the spinal cord.

Answer 21

Ventral Horn

Question 22

The _____________ system houses the primary motor cortex homonculus.

Answer 22

The corticospinal system

Question 23

The corticospinal system houses neurons that project to…?

Answer 23

The ventral horn of the spinal cord

Question 24

The ___________ system houses the semicircular canal and otolith organs.

Answer 24

Vestibulospinal system

Question 25

The Vestibulospinal system has axons that extend to...?

Answer 25

The spinal cord

Question 26

The _________ system is the control system capable of producing fixed motor patterns.

Answer 26

Reticulospinal system

Question 27

The reticulospinal system runs down (which areas of the brain) adnd projects to...?

Answer 27

Runs down the medulla, pons and midbrain. Projects to the ventral horn.

Question 28

In addition to the medulla, pons, and midbrain, the reticulospinal system runs through which region?

Answer 28

The mesencephalic locomotor region.

Question 29

Which system is also called the "red nucleus"?

Answer 29

Rubrospinal system

Question 30

The rubrospinal system projects to where?

Answer 30

The spinal cord

Question 31

The _______ system gets inputs from the cerebellum, and outputs to the cerebellum.

Answer 31

Rubrospinal

Question 32

T/F: The primary motor cortex is a system with pockets of neurons for a body part in the motor homonculus.

Answer 32

False. This is an oversimplified explanation

Question 33

T/F: Axon terminals in the ventral horn spread out and contact many motor neurons.

Answer 33

True!

Question 34

Primary motor cortex neurons ______ to different muscles.

Answer 34

Diverge

Question 35

Alpha motor neurons _______ to contact a single muscle.

Answer 35

Converge

Question 36

________ cells of the primary motor cortex send projections to the spinal cord.

Answer 36

Pyramidal cells

Question 37

Fast twitch fibers release energy (ATP) via _______.

Answer 37

Glycolysis

Question 38

Which system is involved with locomotion?

Answer 38

Reticulospinal