Neuro Flashcards
(25 cards)
Neurology
The study of the anatomy, physiology, and pathology of the nervous system
Afferent fibers
Sensory
Brings signal away from sensory neurons to brain
Efferent fibers
Motor
Brings signal from brain to neuromuscular system junction
Inter
between structres
Intra
within a structure
Decussation
crossing over from midline
Ipsilateral
same side
contralateral
going over to the opposite side
Central Nervous System
- Mediates all communication in the body
- NO direction communication between any two body parts
- Consists of brain and spinal cord (SC)
- Protected by bony shell, three membranous coverings (called meninges - dura, arachnoid, pia mater) and cerebrospinal fluid
Dura mater
The outermost layer that is directly underneath the skull. It is tough, fibrous and inextensible. It consists of two layers, periosteal and meningeal.
Arachnoid mater
The middle layer that lies directly beneath the dura mater. It is translucent and pliable
Pia mater
The innermost layer of the meninges. It is relatively very thin and fragile. This layer is adherent to the surface of the brain and spinal cord following the gyri and sulci of the brain’s surface. The gyri are the ‘ridges’ and the sulci are the ‘furrows’, which together form the undulating folds of the brain’s surface
Peripheral Nervous System (PNS)
Nervous system NOT including the CNS
Motor (efferent) and sensory (afferent) nerves from periphery
Cranial and spinal nerves
CN I
Special sensory - Olfactory
Smell (information integrates with taste and flavor)
CN II
Special sensory - Optic
Vision
CN III
Motor - Oculomotor
Eye movement: lid, pupil, lens
CN IV
Motor: Trochlear
Eye movement (superior oblique): rotation
CN V
BOTH SENSORY AND MOTOR - Trigeminal
Sensory (touch, pain, temperature)
- Opthalmic (sensory only)
- Maxillary
- Mandibular
Motor (maxillary and mandibular branches)
- Muscles of mastication
- Tensor veli palatini
-Upward, anterior movement of larynx
CN VI
Abducens/abducent - motor
Eye movement: lateral rectus muscle
CN VII
BOTH SENSORY AND MOTOR - Facial
Sensory - taste (anterior 2/3 of tongue - sweet, sour, bitter)
Motor - innervates muscles of facial expression (and stapedius)
- Corticobulbar fibers to motor neurons for lower ½ of face
(mostly crossed) - Corticobulbar fibers to motor neurons in upper ½ of face
(distributed bilaterally)
CN VIII
Mostly sensory- Vestibulocochlear/vestibuloacoustic/auditory
- Auditory information
- Vestibular feedback
- Enter brainstem at lower pontine region
- Some vestibular fibers terminate in cerebellum
Testing:
-Audiologist (hearing), ENT: dizziness, tinnitus, Neurologist
CN IX
BOTH SENSORY AND MOTOR - Glossopharyngeal
Sensory
- General sensation from palate,
- Posterior 1/3 of tongue (bitter), pharynx
Motor
- Contributes to swallowing, innervation of stylopharyngeus and
upper pharyngeal constrictors (muscles aiding in swallow)
- Autonomic control of visceral organs (glands)
CN X
BOTH SENSORY AND MOTOR - Vagus
Sensory: from visceral organs, pharynx, larynx
Motor:
-Innervates muscles of larynx, pharynx, velum
-Dorsal motor nucleus- Autonomic motor information to visceral organs
Coronary circulation, HR, tracheal and bronchial contraction
and relaxation
● Autonomic reflexes
■ Synapses on cardiac muscles
Testing
■ Palatal elevation
■ Gag reflex
■ If both volitional and reflexive movement of palate diminished
suspect LMN lesion
○ Assessing: swallowing, voice evaluation, laryngoscopy, videostroboscopy
CN X innervation
■ Superior laryngeal branch
● Sensory to mucous membrane down to vocal folds
● Controls cricothyroid muscle—important for phonation/pitch
■ Recurrent laryngeal branch
● Innervates intrinsic muscles of larynx and epiglottis (overall
motor control to larynx)
● Also receives afferent projection (sensory)
● Part of reticular feedback
CN XI
Motor: Accessory
○ Contains LMN for trapezius and sternocleidomastoid
○ Turning the head and moving the shoulders
-Ipsilateral shoulder shrug
-Turning head to contralateral side
