Neuro final

-Cell body lies in the dorsal root ganglion

-Cell body is in the spinal cord or medulla oblongata

-  Cell body is in the thalamus

Inability to perform rapidly alternating movements

Loss of the ability to distinguish between objects through touch and manipulation

Loss of coordination in performing motor acts

Loss of proper coordination between muscles

Inability to judge distance & stop movement at chosen spot

• Fasciculus Gracilis
• Fasciculus Cuneatus
• Anterior Spinothalamic
• Lateral Spinothalamic
• Anterior Spinocerebellar
• Posterior Spinocerebellar

• Anterior Corticospinal
• Lateral Corticospinal
• Lateral Reticulospinal (medullary)
• Medial Reticulospinal (pontine)
• Rubrospinal

• Upper Motor Neuron-
• Form descending tracts

• Lower Motor Neuron- 
• Directly innervate skeletal muscle

Clinical signs of damage to the upper motor neuron functions of the corticospinal tract only

• §Pyramidal Weakness
• §No wasting of muscles
• §Spasticity
• §Hyperreflexia
• §Positive Babinski reflex

• §Weakness (paresis)
• §Paralysis (plegia)
• §Atrophy
• §Hypotonia
• §Hyporeflexia or Areflexia
• §Visible spontaneous contractions of motor units

§ limbs opposite (contralateral) to the side of the lesion

§limbs on the same side as (ipsilateral to) the lesion

falx cerebelli

Vermis

• •Operates at unconscious level
• •Controls the maintenance of equilibrium
• •Influences posture and muscle tone
• •Coordinates movement

A skin area innervated by the sensory fibers of a single nerve root

A group of muscles primarily innervated by the motor fibers of a single nerve root

• I     Olfactory                       S
• II   Optic                              S
• III    Oculomotor                 M
• IV    Trochlear                     M
• VI    Trigeminal                   B
• VI    Abducens                    M
• VII   Facial                           B
• VIII Vestibulocochlear        S
• IX    Glossopharyngeal        B
• X     Vagus                           B
• XI    Accessory                    M
• XII  Hypoglossal                 M

Sensory – Smell

Sensory – Vision

Motor    – Muscles that raise eyelids, move eyes, adjust amount of light entering the eye & focus lenses

Motor    – Muscles that move one eye

Sensory – Impulses from the surface of the eyes, tear glands, scalp, forehead & upper eyelids

Sensory – Impulses from upper teeth, upper gum, upper lip, lining of the palate and skin of face

Sensory – Impulses from scalp, skin of jaw, lower teeth, lower gum & lower lip

Motor    - Muscles of mastication and muscles in the floor of the mouth

Motor   –  Muscles that move one eye

Sensory – Impulses associated with taste receptors of the anterior of the tongue

Motor  –  Impulses to muscles of facial expression, tear glands & salivary glands

• Sensory – Impulses associated with equilibrium
• Sensory – Impulses associated with hearing

Sensory – Impulses from the pharynx, tonsils, posterior tongue and carotid arteries

Motor    – Impulses to salivary glands and to muscles of pharynx for swallowing

Sensory – Impulses from pharynx, larynx, esophagus & viscera of thorax & abdomen

• Motor    – Somatic motor impulses to muscles associated with speech and swallowing              
•              – Autonomic motor impulses to viscera of the thorax & abdomen

• Motor   –  Impulses to muscles of the soft palate, pharynx and larynx
• Motor   –  Impulses to muscles of the neck and back; some proprioception input

Motor   –  Impulses to muscles that move the tongue                

Protects brain & spinal cord

Space between the dura mater and the periosteum of the bone (skull)

• Space between the dura mater (meningeal layer and arachnoid)
• Filled with thin film of fluid (may fill w/blood as with hemorrhage)

Space between the arachnoid mater and the pia mater

• Dura mater
• Arachnoid Mater
• Arachnoid Granulations (villi)
• Pia Mater

• Tough, outermost membrane- 
• Splits into 2 layers forming channels called the dural sinuses   
• Periosteal Layer – outermost layer 
• Meningeal Layer – innermost layer

-  Thin, web-like membrane that is located between the dura & pia mater

• Small, mushroom shaped protrusions (finger-like    projections) of  arachnoid- 
• Located in the dural sinuses - 
• Re-absorb CSF into the venous system

• Very thin, inner layer that clings or attaches to brain surface- 
• Dips into grooves & contours

• Dura Mater
• Arachnoid
• Pia
• Filum Terminale

-  Composed of only one meningeal layer

-  Continuous with the cranial arachnoid

-  Closely conforms to the spinal cord

– Pia mater gathers into a very thin, non-nervous filament at the conus medullaris

Dura mater dips or folds down into the median longitudinal fissure between (separates) the right & left cerebral hemispheres

Tentorium cerebelli Dura also dips or folds down into the space between the cerebellum and the overlying occipital lobes forming a tent-like covering over the cerebellum  (separates occipital lobes of the cerebrum from the cerebellum)

Dura mater dips between (separates) the two cerebellar hemispheres

§  Spinal Pia mater gathers into a very thin, non-nervous filament at the conus medullaris

§  Extends for approximately 20cm

§  Attached to the periosteum of the first     coccygeal vertebra§  Helps anchor and stabilize the spinal cord

• §Dentate Ligaments
• §Toothlike extensions
• §Located on each side of the entire spinal cord
• §Attached to the arachnoid and dura
• §Serve to anchor and stabilize the spinal cord

• Pair of C-shaped structures with “horns”- 
• The C-shape allows the ventricles to reach into all lobes of the cerebrum

-Connects the lateral and third ventricles

Floor of the third ventricle is formed by the hypothalamus-Walls are formed by right/left thalamus

Connects the third & fourth ventricle

• -  Extends laterally into each cerebellar hemispheres forming recesses
• -  Fourth ventricle narrows inferiorly and becomes the central canal of the spinal cord

Clear lymph-like fluid that is produced by the choroid plexus located in the lateral, third & fourth ventricles 

• Fills the entire subarachnoid space which surrounds the brain and spinal cord
•  
• Protective cushioning for brain & spinal cord

• -  Right & Left Internal Carotid Arteries
• -  Right & Left Vertebral Arteries

• -Anterior cerebral arteries
• -Middle cerebral arteries

Connects the Right & Left Anterior Cerebral Arteries

 striate arteries

• -Frequent site of CVAs
• -Known as “arteries of stroke”

-  Connects the middle cerebral and posterior cerebral arteries

• Anterior Spinal & Posterior Spinal arteries 
• Posterior Inferior Cerebellar arteries Basilar artery
• -Joins together to form Basilar artery

Posterior Cerebral Arteries

• -  Three longitudinal vessels run the length of the spinal cord-  
• Insufficient to supply the cord below cervical levels

Serial reinforcement or Supplemental arteries for the spinal cord

-Receives blood primarily from the superior cerebral veins and superior anastomotic vein

-Receives flow of veins from the medial aspect of the hemisphere

-  The Great Cerebral vein runs into the Straight Sinus

Convergence of the Superior Sagittal and Straight Sinuses

• Blood flows laterally from the confluence and also receives blood from the cavernous sinus
• -Continuous with the Sigmoid sinus

• -  Continues from the transverse sinus
• -  Joins the Internal Jugular vein at the level of the jugular foramen

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