Exam 1 (The Motor System)

Components of the Motor System: -The _ consists of the brain and the spinal cord. -The _ consists of 12 pairs of cranial nerves and 31 paris of spinal nerves. >The cranial nerves project from the _. > The spinal nerves project from the _.

-CNS -PNS >brain >spinal cord

-_ axons terminate in the spinal cord and synapse with cranial or spinal nerves. -_ axons terminate in the brain stem and synapse with cranial nerves.

-corticospinal -corticobulbar

the cerebral cortex: -usually described as the _ matter - _ cognitive activities are performed.

-gray -higher (language, motor planning, problem solving, and much sensory perception)

-Convolution = _ -Vally (groove between) = _

-gyri -sulci

-The _ runs horizontally along the lateral sides of each hem and separates the temporal lobe from the frontal lobe. -the _ is located near the center of the lateral sides of each hem and extends vertically from the very top of theme down to the lateral sulcus. -The gyrus immediately in front of the central sulcus is aka _? -The gyrus just behind the central sulcus is known as _?

-lateral sulcus -central sulcus -motor strip -sensory strip

-The _ plays an important role in controlling the voluntary movements of the body. -the _ plays a role in higher center of brain receive sensory info from the body via the PNS and other portions of the CNS.

-motor -sensory

-an example of _ system carries the motor impulses that enable a person to make coordinated, independent, finger movements when typing on a keyboard. -an example of _ system carries the impulses to keep the arms, should, and back in a position that permit the fingers to move over their keyboard.

-pyramidal -extrapyramidal

-the _ system is responsible for carrying the impulses that control voluntary, fine motor movements. -_ system transmits impulses that control postural support need by those fine motor movements.

-pyramidal -extrapyramidal

-UMN damage results in ? -LMN damage results in?

-spasticity -muscle paralysis/ flaccid dys

-_ nerves innervate most of the other muscles of the body including the chest, arms, and legs. -_ nerves innervate many organs and muscles of the head, neck, thorax, and abdomen.

-spinal nerves -cranial nerves

The postural muscles controlled by the extrapyramidal system include those of the _, and the larger muscle groups of the _ and _.

-torso, arms, and legs.

-When bundles of axons are found in the CNS they are most often ? -When bundles of axons are found in the PNS they are most often ?

-tracts -nerves

-_ motor neurons are DESCENDING and course through the CNS eventually to the PNS. (corticobulbar, coritcospinal, and extrapyramidal paths) -_ motor neurons are the motor neurons in the cranial and spinal nerves.

-upper motor (they are motor fibers within the CNS) -Lower motor neurons

The principal role of the primary cortex is: a. to take _ movement patterns that are formulated elsewhere b. to transmit them to the cranial or spinal nerves via the _/_neurons.

-voluntary -pyramidal/motor neurons

-Most of the cerebrum is composed of _ matter located below the _. -This white matter consists of _ _ that course to and from other parts of the CNS. -This color is from the _ that covers the axons.

-white, cortex -nerve cell axons -myelin

The cerebrum is organized into 4 lobes: 1. frontal lobe located on the _ position of the cerebrum. 2. temporal lobe lies on the _ of the cerebrum. 3. parietal lobe is found on the _ of cerebrum, behind the _. 4. occipital lobe lies on the _ of the cerebrum, behind the _ lobes.

1. anterior 2. lower sides 3. upper sides, behind the frontal 4. rear-most portion, behind parietal and temporal

3 primary functions of the brain stem: 1. It acts as a _ for ascending and descending neural tracts that travel between the cerebrum and spinal cord. 2. It controls certain _ and _ actions, such as respiration, consciousness, and some parts of the cardiovascular system functions. 3. It contains the places where the _ project _ from the CNS.

1. passageway 2. integrative and reflexive 3. cranial nerves, out

The normal adult brain weighs about ?

2.5-3.5 lbs

What is the most important function of the brainstem with regard to the motor speech system?

It contains the places where cranial nerves project out form the CNS.

_ are the cells that transmit the electrochemical signals that control nearly every function of the body.

Neurons. (body contains approx. 50 to 100 billion neurons)

Association Cortex: a. -_ it is involved with the recognition of complex visual stimuli, integrating aud stimuli with other centers of the brain, and the formation of memories. -damage to this area can result in _ _, amnesia, and high levels of _. b. -_ It is involved with visually guided movements. -damage may include _ blindness, _ blindness, _ c.- _ is responsible for integrating bodily sensation and visual info. it plays an important role in the control of visually guided movements (hand-eye coordination) -damage can cause impairments in _ objects, sensory neglect of _, and _ difficulties. d. _ plays an important role in initiating and planning of volitional movements of volitional movements. -bilateral damage can result in decreased _ and _, shortened attention span, and dif with _.

a. -temporal association (is located on the temporal lobe.) -visaul amnesia, distractablitiy b. -visual association area (runs between the primary visual cortex and the parietal and temporal lobes.) -motion, color, prosopagnosia c. -parietal association - manipulating, half of the body, reading/writing d. frontal association -spontaneity, initiative, abstract prob solving

Damage to cerebellum can result in a variety of disorders: a. _, a disturbance in speed, range, and direction of movements. (muscles near shoulders and pelvis are affected; wide-based gate; "drunken" character" b. _, is caused by lesions of the cerebellum. (only observed during performance of voluntary movements, such as reading, drinking water) c. nystagmus, increase or decreased _ _, disturbances of _.

a. ataxia b. intention tremor c. muscle tone, equilibrium

Types of Neurons: a. link neurons with other neurons. b. transmit their impulses away from the CNS. c. carry info related to sensory stimuli. d. transmit neural impulses that cause contraction in muscles. e. transmit their impulses toward the CNS.

a. interneurons b. Efferent- Motor c. sensory neurons d. motor neurons e. afferent- sensory

Primary Cortex: a. _ It is thought to analyze the patterns and sound properties, and it may help in the localization of sound. The more sophisticated analyses of sound are completed in other areas. b. _ This is where the cortex receives the first neural input about bodily sensation. The analysis includes sensations or pressure, temp, touch, and pain. c. _ It is thought to perform a preliminary analysis of depth and perhaps integration of visual info from both eyes. Damage to this area can result int he loss of conscious awareness of visual stimulation. d. _ works in a comparable but reversed manner. It receives planned motor impulses from cortical and subcortical areas of the brain and send those impulses down through the brainstem and spinal cord, where they are eventually sent to the muscles.

a. primary auditory cortex b. primary sensory cortex c. primary visual cortex d. prim motor cortex

_ and _ are 2 neurotransmitters that are important in the motor system.

acetylcholine and dopamine

The motor speech disorder usually associated with cerebellar lesions is ?

ataxic dysarthria

_ especially important in planning of slow, continuous movements.

basal ganglia

The association cortex sends its neural signals of an intended motor movement to ?

basla ganglia and cerebellum

The _ helps to regulate muscle tone, maintain balance, and coordinate skilled motor movements.

cerebellum

The _ is the surface of the cerebrum?

cerebral cortex

_ is the largest division of the brain.

cerebrum

The brainstem sits between the _ and _?

cerebrum and spinal cord

What is the most important function of the cerebellum to _ voluntary movements so that muscles contract with the correct amount of force and at the appropriate _.?

coordinate time

The fibers of the pyramidal system are divided into ?

corticospinal and corticobulbar

When a portion of the motor system is damaged the result can be a _ _ _.

debilitating motor disorder

The most obvious feature of the cerebrum is _?

deep convolutions

The _ _ tracts are the neural pathways carrying motor impulses that travel from the cortex to the brainstem and spinal cord.

descending motor

The cerebellum has _ neural tracts that indirectly synapse with _ extrapyramidal tracts.

efferent, descending (through these connections with the extrapyramidal motor neurons, the cerebellum influences motor activities as walking and maintaining posture.

The _ system influences the reflexes, muscle tone, and some voluntary movements of the speech mechanism.

extrapyramidal

The _ system is composed of a number of different, interconnected descending motor pathways.

extrapyramidal

t/f: Compared to most other animals, humans have small brains relative to body size.

false,

t/f: Intention tremors are present when an indv is at rest.

false, it is NOT

t/f: Primary motor cortex is the designer of purposeful, sequenced movements.

false, only simple muscle contractions are observed

t/f: The cerebrum adjusts and refined the motor impulses according to the boys immediate circumstances and sends these processed motor signals to the primary motor cortex via the thalamus.

false, the cerebellum does

t/f: Most planning for movement originates in the primary motor cortex. **

false, the initial planning of movement is formulated primarily in the association cortex.

Cerebellar damage can cause significant deficits in the performance of _ motor actions?

fine and gross (movements such as walking, writing, and speech can become uncertain and awkward)

Are there more glial cells or neurons in the nervous system?

glial cells (about 10 x's as many)

The motor speech disorder associated with Parkinsons is ?

hypo kinetic dysarthria

-tight restricted movements =? -apid, involuntary movements of the extremities, face and tongue =?

hypo kinetic-Parkinson hyperkinetic-Hungtintons

Direct electrical stimulation of the primary motor cortex has show that its neurons are arranged in _ body scheme.

inverted (ex: when muscles at the bottom of the pre central gyrus occur, contractions happen in the sea dead neck)

The cerebrum is divided into _?

left and right hemispheres

The type of disorder is dependent on the _ and _ of the damage to the motor system.

location and extent

The brainstem is divided into what?

midbrain, pons, and medulla

The thalamus receives neural impulses of _ _ movements form both the basal ganglia and cerebellum.

planned motor

_ is the area of the cortex that, in conjunction with other parts of the brain, makes sense of the sensory impulses that have been initially analyzed by the primary cortex .

primary association cortex

The _ comprises the parts of the cerebrum that are decimated tot he analysis of a single type of neural input.

primary cortex

The basal ganglia and cerebellum take the rough motor impulses from the assoc cortex, smooth them out, and then send them to ?

primary cortex (via thalamus)

The _ receives the neural motor impulses that have been processed, smoothes, and coordinated by the basal gan, thal, and cerebellum.

primary motor cortex

4 types of glial cells:

schwann cells, microglia, oligodendroglia, and astrocytes

What are the 3 primary components of neurons?

soma(cell body), dendrites(receive impulses), axon(extension form the cell body)

In the motor system an imbalance between excitatory and inhibitory neurotransmitters may be a cause of _.

spasticity (this results form excessive contractions of the muscles innervated by highly excited neurons that did not receive the counterbalancing inhibitory neurotransmitters.

_ is the doorway which subcortical systems of the nervous system communicate with the cerebral cortex.

thalamus

The cerebellum is attached to _?

the back of the brainstem

Almost all activity of the nervous system originates in or is ultimately processed by _?

the brain

What is the brain divided into?

the cerebrum, cerebellum, and brainstem

The motor system is what allows _ to be turned into movement.

thought

The function of a neuron is to _ neural impulses form one part of the nervous system to another.

transmit (neuron does this by conducting a small electrochemical charge along the axon)

t/f: Muscles contractions near the leg and foot are observed when neurons near the top of gyrus are stimulate.

true

t/f: The motor system can work at a conscious or subconscious level.

true

t/f: The primary aud cortex, prim vis cort, and prim sens cortex are all similar in that they are the first cortical areas to analyze sensory info.

true

t/f: The pyramidal systen consists of motor neurons that make a mostly direct course from the cortex to the spinal cord or to the brainstem.

true

t/f: basla ganglia are mostly inactive during rapid, back and forth movements.

true

t/f: practically every sensory impulse form the body passes through the thalamus on its way to the cortex.

true (thalamus uses this sensory info to further refine the motor impulses from the basal ganglia and cerebellum)

t/f: The neurons in the primary motor cortex have axons that are among the longest.

true( these axons make up most of the pyramidal system)

t/f: the assoc cortex is not a single region of the brain.

true, it is distributed over 4 areas

The parts of the nervous system that control _ movements are known as collectively as the motor system.

voluntary