Lateral Spinothalamic Tract (function, receptors, path, lesion)
- Pain and temp
- Free nerve endings
- Ascends in lateral column of spinal cord (decussates at anterior commissure immediately); goes to sensory cortex in parietal lobe
- Lesion causes loss of pain and temp (half spinal cord will cause contralateral loss below level and ipsi at level)
Anterior Spinothalamic Tract (function, receptors, path, lesion)
- Crude touch and pressure
- Merkel’s discs and Ruffini corpuscles and free nerve endings
- Ascends in anterior white column (decussates immediately); goes to sensory cortex
- Half lesion = ipsi loss at level and contra below
Dorsal Columns (function, receptors, path, lesion)
- Fine touch, conscious proprio, vibration
- Pacinian corpuscles, Merkel’s discs, Meissner’s
- Ascends in dorsal column and crosses in medulla to go to sensory cortex
- Lesion below medulla = ipsilateral loss; above medulla = contra loss
Lateral Corticospinal (function, path, lesion)
- Primary motor
- Descends from primary motor and crosses in pyramids; synapses in anterior horn in spinal cord to alpha motor neuron
- Lesion above medulla = contralateral loss
Anterior Corticospinal (function, path, lesion)
- Primary motor (10% that cross at level of innervation)
- Travel in ventral white column
- Lesion of half the cord = loss of 10% contralaterally
Olfactory Nerve (function, test, damage)
- Smell
- Introduce non irritating smells to one nostril at a time
- Anosmia (inability to detect smells; seen in temporal lesions)
Optic Nerve (function, test, damage)
- Vision
- Visual acuity, peripheral vision
- Blindness, honomynous hemianopia
Oculomotor Nerve (function, test, damage)
- Motor - inferior oblique and medial, superior and inferior rectus, levator palpebrae
Autonomic - sphincter papillae and cilliary muscles (pupillary reflex) - Look at pupil size, shape, equal, light reflex, follow finger
- Absence of pupillary reflex, unequal pupils, pupil dilation
Trochlear Nerve (function, test, damage)
- Superior oblique muscle
- Test with oculomotor nerve, isolated eye movements
- Eyes can’t look down when adducted
Trigeminal Nerve (function, test, damage)
V1 - ophthalmic - sensory for scalp and forehead
V2 - maxillary - sensory for area below eyes and above mouth
V3 - mandibular - sensory for lower lip, chin, jaw, muscles of mastication
- Pain and light touch on face, open and close against resistance
- Numbness, weakness of mastication, jaw deviation when opened to ipsilateral side
Abducens Nerve (function, test, damage)
Motor - lateral rectus
- Observe eye position
- Eye pulled inward, can’t look out
Facial Nerve (function, test, damage)
Sensory - taste from ant 2/3 of tongue
Motor - muscles of facial expression
Autonomic - parasympathetic control of lacrimal, nasal mucosal, submandibular and sublingual glands
- Motor function of facial muscles looking for asymmetry
- Bell’s palsy (LMN = ipsi; UMN = conta)
Vestibulocochlear Nerve (function, test, damage)
Sensory - hearing, head position in space
- Examine balance, gaze stability, auditory
- Can cause vertigo, disequilibrium, nystagmus, deafness, tinnitus
Glossopharyngeal Nerve (function, test, damage)
Sensory - touch and taste post 1/3 of tongue, visceral sensory from carotid bodies
Motor - pharyngeal muscle
Autonomic - increase secretion from parotid salivary gland
- Voice quality, swallowing, uvular deviation, gag reflex
- Dysphonia, dysphagia, absent gag reflex
Vagus Nerve (function, test, damage)
Sensory - visceral sensation
Motor - pharyngeal and laryngeal muscles and muscles at base of tongue, elevates soft palate, controls uvula
Autonomic - smooth muscle/glands of heart, lungs, larynx, trachea and most abdominal organs
- Test with glosso
Accessory Nerve (function, test, damage)
Motor - traps, SCM
- MMT, muscle bulk
- Atrophy, inability to shrug or turn head to contra side
Hypoglossal Nerve (function, test, damage)
Motor - intrinsic and extrinsic muscles of tongue
- Protrude tongue and observe for deviations
- Dysarthria, deviation of tongue to weak side
What are the 10 principles of neuroplasticity?
Use it and improve it, use it or lose it, specificity, repetition, intensity, time matters, age matters, transference, interference
Flexor synergy
UE = elbow flex, ER and and of shoulder, wrist flex LE = hip flex, knee flex, DF and inv of foot
Extensor Synergy
UE = shoulder adduct and IR, elbow ext and pronation, wrist ext LE = hip ext + IR, knee ext, ankle PF and inversion
Broca’s Aphasia
Difficulty speaking and writing (knows what wants to say but can’t get it out = motor deficit)
Wernicke’s Aphasia
Inability to understand language and formulate thoughts for communication (word salad)
