Axons in the corticobulbar tract terminate in.
The brainstem
The spinal cord
Extrafusal muscle fibres
Intrafusal muscle fibres
The relatively large cells in layer 5 of the primary motor cortex.
Betz cells
Non-Betz cells
Neurons
White matter
Axons in the corticospinal tract terminate in.
Neurons in the primary cortex require very low intensity stimulation for activation and have a stimulation to muscle response delay of about...
10ms
1s
1 microsecond
30 seconds
A single upper motor neuron is thought to control.
A specific muscle
A specific movement
An upper motor neuron will fire more or less often when the direction of movement is near their prefferred direction?
Less
More
The population vector is...
An individual neurons preferred direction
The exact direction of a neurons specific direction
The sum of each individual neurons firing rate for a movement direction
Neurons in the pre-motor cortex are thought to fire...
When planning a movement
When performing a movement
After a movement
In response to spiders
Muscles in the face and neck are controlled by axons from the.
Corticobulbar tract
Corticospinal tract
Reflexive muscle fibres
The medial superior olive
The proximal and distal muscles are controlled by the axons from
The corticospinal tract
The corticobulbar tract
The medial superior olive (MSO)
The lateral superior olive (LSO)
Axons in the corticospinal tract have what characteristic?
A latency of about 70ms
They control facial and neck muscles
90% of axons cross the midline
The muscle field is?
The group of muscles controlled by a given upper neuron
A motor unit
An alpha motor neuron
The specific muscle controlled by an upper motor neuron
Mirror neurons fire...
When watching a movement and while also performing the same movement
Only when watching a movement
Only when performing a movement
In response to non-movement stimuli
Spike triggered averaging is used to correlate muscle contractions with stimulation of upper motor neurons.
Posture stabilizing actions in secondary muscles occur in response to the primary movement...
Before the movement occurs
After the movement occurs
At the same time as the movement
Only as nessesary