Exam 3 Week 12 ppt 11 Voluntary Movement

Question 1

Motor Control is

Answer 1

the ability to regulate or direct the mechanisms essential to movement

Question 2

Motor Planning is

Answer 2

the preliminary organization prior to movement

Question 3

Programming is

Answer 3

the specifications that allow movement to progress

Question 4

Motor Cortical Areas have _ main area (and what are they)

Answer 4

3 ~frontal areas ~parietal areas ~limbic areas

Question 5

What are the _ parts of the frontal area for motor cortical areas?

Answer 5

3 ~primary motor ~supplementary motor ~lateral pre-motor

Question 6

What is the main part of the parietal area for motor cortical areas?

Answer 6

posterior partial area

Question 7

What are the _ main parts for the limbic area for motor cortical areas?

Answer 7

2 ~anterior cingulate areas ~posterior cingulate areas

Question 8

Where is the primary motor cortex located?

Answer 8

precentral gyrus; Brodmann’s area 4

Question 9

Where is the supplementary motor cortex located?

Answer 9

most superior and medial aspects of superior frontal gyrus; just rostral to the primary motor cortex

Question 10

Where is the pre-motor cortex located?

Answer 10

along the lateral frontal cortex; just rostral to the primary motor cortex and along most of its length

Question 11

Somatotopic organization of the primary motor cortex

Answer 11

~homunculus ~LE – dorsomedial ~UE & face– ventro-lateral ~also has a fractured somatotopy

Question 12

fractured somatotopy

Answer 12

overlapping regions and scattered distributions of motor neurons with innervate specific muscles

Question 13

example of fractured homunculus in the cortical motor neurons

Answer 13

~Using the intrinsic thumb muscles as an example, CM neurons for the thumb instrinsic muscles are over all 4 regions ~There is overlap with cortical motor neurons innervating the finger muscles in one area but in other areas thumb muscle cortical motor neurons overlap with wrist, orofacial and even trunk cortical motor neurons

Question 14

Primary motor cortex and it’s role in movement

Answer 14

~some debate as to the role of the Primary motor cortex in movement ~Most agree it is the Lowest level of motor cortical hierarchy – an irony that the “primary” motor cortex is actually the lowest in the hierarchy ~controversy comes with the debate between those who feel that the primary motor cortex Encode specific muscle kinetic features such as the amount of force for specific movement versus those who feel that it specializes in the Kinematic features, that is speed, direction & spatial path. Both may likely be its function.

Question 15

Supplemental motor cortex somatotopic

Answer 15

~face, UE & LE arranged in a rostral-caudal orientation

Question 16

Supplemental motor cortex and its role in movement

Answer 16

~Stimulation of this area elicits movements but in complex synergy patterns ~Active up to 120 ms before movements occur; suggesting a site for motor planning ~strengthened by SMA projections to basal nuclei and cerebellum which help in organization of the movement performed by the primary motor cortex

Question 17

Damage to supplementary motor cortex will cause

Answer 17

~Damage to the Supplementary Motor Cortex produces problem in bimanual tasks, motor memory and motor learning

Question 18

Premotor cortex and its role in movements

Answer 18

~Rough somatotopic organization that parallels the primary motor cortex ~synergy patterns when stimulated ~some debate whether kinematic features of targeting movements here rather than 1° motor cortex

Question 19

posterior parietal cortex and its role in movement

Answer 19

~Critical for providing spatial information for goal-directed movement ~provides the knowledge of Spatial relationships of the environment and how these impact the movement as it takes place ~Critical spatial information for goal-directed movement such as the relative Orientation of the body toward the goal directed objects and determination of the Relative shapes & sizes & orientation of objects within the environment

Question 20

Limbic cortex- somatotopic

Answer 20

face to feet in rostral-caudal

Question 21

Limbic cortex- contributes to/ projects to

Answer 21

~contributes along with the parietal lobe to about third of pyramidal tract neurons ~Cingulospinal projections terminate in the intermediate gray, influencing LMNs via interneurons ~anterior cingulate cortex Receives widespread input from amygdala and non-motor areas of cingulate gyrus

Question 22

anterior cingulate gyrus (function)

Answer 22

provides motivational and reward (goal of performance) information

Question 23

Cortical connections related to motor function- inputs

(info & list 5 locations)

Answer 23

• Input to the primary motor cortex comes from the 1° somatosensory areas analogous to the regions of 1° motor cortex (particularly hand region
• Input into the 1° motor cortex from:

1. pre-motor cortex
2. SMA
3. CMA (Cingulate motor area)
4. DLPFC (Dorsolateral prefrontal cortex)
5. Posterior parietal input

Question 24

DLPFC (Dorsolateral prefrontal cortex) input details

Answer 24

~input into 1° motor cortex and into SMA & CMA ~input provides for Short term memory for action related sensory information, for the Preparatory motor set ~allow for the Inhibition of motor response to distracting stimuli

Question 25

What are two types of sub-cortical connections?

Answer 25

~basal nuclei loop ~Cerebellar loop

Question 26

Basal Nuclei Loop

Answer 26

~Supplementary motor cortex projects to the to the striatum ~direct and indirect pathways within the basal nuclei ~incorporation of the substantia nigra with then the normal outputs of GPi/SNr to VL/VA thalamus then onto 1° motor cortex

Question 27

Cerebellar Loop

Answer 27

~1° motor cortex & pre-motor cortex to pontine & inferior olivary nuclei ~pontocerebellar and olivocerebellar fibers have Input to cerebellar deep nuclei & cortex ~Deep nuclei then have output to the VL thalamus & back to 1° motor cortex

Question 28

PAS (perceptual action system)

Answer 28

~purposeful movement does not occur in isolation from the sensory perceptual experience of the environment but requires input from the environment to correctly execute motor action

Question 29

Haptic sensing

Answer 29

~the generation of sensory input from deliberate motor action EX: Exploration of an object by the hand and the Integration of cutaneous and propioceptive information into motor commands ~require working memory which is provided by action of the Dorsolateral prefrontal cortex & posterior parietal cortex

Question 30

Saccades

Answer 30

~Ballistic voluntary conjugate eye movements used to capture a visual image onto the fovea of the retina ~Used in reading and visual scanning ~Motor programs for saccades reside in reticular formation of midbrain & pons – central pattern generator for conjugate eye movement.

Question 31

Superior Colliculus control movement by

Answer 31

~Coordinates movements of the eyes via tectobulbar projections (to reticular formation central pattern generator neurons) ~Coordinates movements of head via the tectospinal tract (to cervical spinal cord)

Question 32

frontal eye field is located

Answer 32

middle frontal gyrus rostral to premotor cortex

Question 33

frontal eye field function

Answer 33

generates contralateral horizontal conjugate eye movement

Question 34

frontal eye field projections

Answer 34

~superior colliculus ~reticular formation

Question 35

supplementary eye field projects to

Answer 35

~brainstem ~frontal eye field

Question 36

parietal eye field projects to

Answer 36

~brainstem ~frontal eye field

Question 37

function of Wernicke’s area

Answer 37

hearing and interpretation of language command

Question 38

function of posterior parietal cortex

Answer 38

placing command within the movement space = spatial env and coordination of eye movement to that site of placement

Question 39

What are four inputs to the primary motor cortex?

Answer 39

1. 1° somatosensory input to analogous regions of 1° motor cortex (particularly hand region) (a) 2. SMA, CMA prefrontal input into 1° motor cortex (a) 3. Dorsolateral prefrontal cortex (DLPFC) input into 1° motor cortex (b) 4. Posterior parietal input to 1° motor cortex (b)

Question 40

What is the function of saccades?

Answer 40

~Ballistic voluntary conjugate eye movements used to capture a visual image onto the fovea of the retina

Question 41

what tasks are saccades used for? (2)

Answer 41

~Used in reading and visual scanning

Question 42

where do motor programs for saccades reside? What can these locations be referred to as?

Answer 42

~Motor programs for saccades reside in reticular formation of midbrain & pons – central pattern generator for conjugate eye movement.

Question 43

describe the somatotopic organization of the premotor cortex

Answer 43

~Rough somatotopic organization that parallels the primary motor cortex

Question 44

what can happen when premotor cortex is stimulated?

Answer 44

synergy patterns

Question 45

what is a debate about the premotor cortex?

Answer 45

~some debate whether kinematic features of targeting movements here rather than 1° motor cortex