Unit 3_Cortex & Motor Systems

Question 1

What area of the cortex is engaged in Primary Motor Cortex-Execution?

Answer 1

Area 4

Question 2

What area of the cortex is engaged in Supplementary Motor Cortex

Answer 2

Area; SMC or SMA

Question 3

What area of the cortex is engaged in Premotor Cortex-Planning?

Answer 3

Area 6, lateral

Question 4

What area of the cortex is engaged in Supplementary Motor Cortex-Planning?

Answer 4

Area 6, medial

Question 5

What is located in the precentral gyrus of frontal lobe? Includes neurons that control the L/E are primarily on the medial side of cortex (Anterior Cerebral Artery).
Neurons that control the U/E and face are primarily are on the lateral side of the cortex (Middle Cerebral Artery).

Answer 5

Primary Motor Cortex

Question 6

Where are the following functions located?
- Initiates and executes voluntary skilled complex movements.
- Regulates force, direction, and speed of complex movements
Important for isolating joint movement –FRACTIONATION.
- Producing synergistic actions by activating multiple muscle groups and or movements at multiple joints at once.

Answer 6

Primary Motor Cortex

Question 7

Where are the following functions located?
- Control reciprocal movements by simultaneously activating a muscle while inhibiting the antagonist.
- Mediates muscle co-contraction (when agonists and antagonists need to contract together).
- Contributes to the establishment of postural stability required in anticipation of voluntary movements (Which pathways?)

Answer 7

Primary Motor Cortex

Question 8

What areas are sending afferent communication into the primary motor cortex?

Answer 8

direct path from sensory cortex (sensory info)
basal ganglia
Cerebellum
premotor cortex (motor planning info)
supplementary motor cortex (motor planning info)

Question 9

What are the following pathways communicating away from the primary motor cortex?
corticospinal (ventral and lateral) to spinal cord
corticobulbar (Corticonuclear) to brainstem areas

These pathways will terminate on alpha motor neurons, gamma motor neurons, and interneurons in the ventral horn of the spinal cord and in cranial nerve motor nuclei.

Answer 9

Efferent Connections/Direct Pathways

Question 10

What are the following pathways communicating away from the primary motor cortex?
basal ganglia (corticostriatal)
cerebellum (corticopontine)

These pathways influence the output of these other motor control centers.

Answer 10

Efferent Connections/Indirect Pathways

Question 11

What are two conditions under which primary motor cortex lesion may give rise to hypotonia rather than spasticity? Present on the contralateral side of the body
lateral cortex-U/E>L/E, medial cortex-L/E>U/E.

Answer 11

May INITIALLY have flaccid paralysis due to cerebral shock for about 1 week this often will convert to spasticity after the period of cerebral shock
May occasionally see long term hypotonia if the lesion is very extensive

Question 12

What is located Immediately anterior to primary motor cortex on the medial side? Supplied by anterior cerebral artery.

Answer 12

SUPPLEMENTARY MOTOR CORTEX (SMC or SMA; medial part of Area 6)

Question 13

What functions are associated with the neurons in this area are primarily involved in movement preparation and are active prior to the initiation of movement? More specifically this area is responsible for:

Planning and initiating internally guided movements that are goal directed or complex sequential tasks (i.e. not movements guided by vision, hearing, etc; not guided by external stimuli)
Interacts via corpus callosum with the supplementary cortex on the other side and is, therefore, also important for the control of bimanual tasks

Answer 13

SUPPLEMENTARY MOTOR CORTEX (SMC or SMA; medial part of Area 6)

Question 14

What area is affected with a lesion that does not produce UMN syndrome signs and symptoms?

Impairments:
1. Apraxia: Motor planning disorder (ideomotor) A patient may have intact strength etc. but cannot correctly plan and sequence a movement to accomplish a task
2. Difficulty with tasks requiring coordination of both hands or feet.

These problems are noted most when the patient is using movements stored in internal memory. They will not have as many problems with visually guided movements of the hands and feet.

Answer 14

SUPPLEMENTARY MOTOR CORTEX (SMC or SMA; medial part of Area 6)

Question 15

What is located anterior to primary motor cortex on the lateral hemisphere? Has dorsal and ventral portions. Supplied by middle cerebral artery.

Answer 15

PREMOTOR CORTEX (Area 6)
Works with parietal cortical areas 5 and 7

Question 16

What area is involved with planning and initiating movements that are guided by external stimuli? It controls movements that require sensory guidance. This area would be utilized during guided visual imagery or walking on a narrow beam.

Answer 16

PREMOTOR CORTEX (Area 6)
Works with parietal cortical areas 5 and 7

Question 17

What area is affected with a lesion that will not give you typical UMN syndrome signs and symptoms?

Ideomotor Apraxia
Impairs bimanual coordination

Answer 17

PREMOTOR CORTEX (Area 6)
Works with parietal cortical areas 5 and 7

Question 18

What area includes cells in the primary sensory area typically fire after movement has started which suggests that they are responding to sensory feedback generated by the movement?

Functions:
sensory integration
motor planning by “talking” to PMA and SMA
sensory regulation through corticospinal descending pathway (potentiates or inhibits NON-PAINFUL sensory input to the cortex)

Answer 18

Primary Sensory Area

Question 19

What area is affected with a lesion that does not produce UMN syndrome signs and symptoms?

Motor Deficits
- Contralateral sensory motor ataxia (impairment of coordination)
- Contralateral impaired grip and load force synergies
- Impaired balance

Answer 19

Primary Sensory Area

Question 20

What area is located in the parietal lobe sensory association area? Supplied primarily by middle cerebral artery.

Answer 20

Posterior Parietal Cortex

Question 21

What area includes functions:
- motor planning for movements requiring sensory guidance (like PMA)
- motor imagery and visuomotor memory
- motor learning (active during the learning phase of a motor task)
- Grasping and Reaching

A lesion in this area would feature Ideomotor apraxia similar to that seen in lesions of the premotor cortex.

Answer 21

Posterior Parietal Cortex

Question 22

What area appears to be involved in motor control and is located on the medial aspect of the cortex and is supplied by the anterior cerebral artery? Cells here are active prior to and during movement and this area has been implicated in movement execution during complex behaviors.

In addition, this area may be involved in the emotional control of movements (motivation) since it is part of limbic system.

Answer 22

Cingulate Cortex

Question 23

What area may be involved in the storage of motor memories, it may be involved in motor learning, and it also affects the development of the idea and contribute to motivation to perform a task which affects the ability to perform the task?

This area has lots of connections with the basal ganglia.

Answer 23

Prefrontal Cortex

Question 24

What area is just anterior to the premotor area on the lateral side of each hemisphere? Motor area for control of lateral eye movement.

Answer 24

Frontal Eye Fields

Question 25

What area of the cortex is engaged in Primary Sensory Area-Planning?

Answer 25

Areas 3,1,2

Question 26

What area of the cortex is engaged in Posterior Parietal Cortex-Planning?

Answer 26

Areas 5 & 7

Question 27

What area of the cortex is engaged in Cingulate Cortex-Emotional Motor?

Answer 27

Medial and dorsal to Corpus Callosum

Question 28

What area of the cortex is engaged in Pre-frontal Cortex-Memory and Learning?

Answer 28

Areas 9 & 10

Question 29

What area of the cortex is engaged in Frontal Eye Fields-Eye Movement?

Answer 29

Area 8