Brainstem Flashcards
Longitudinal Divions of BS
-Basilar
-Tegmentum
-Tectum
Basilar Divison
-ventral
-Descending tracts from cortex
-motor nuceli from substantia nigra, pons, inferior olive
Tegmenum Divison
-Dorsal
-reticular formation (arousal)
-sensory nuclei; ascending tracts
-CN V nuclei
-medial longitudinal fasciculus (coordinate eye and head mmt)
Tectum Divison
-midbrain only
-reflexive mmts of eyes and head
-inferior and superior colliculi
Midbrain Divisions
-Basis Pedunculi
-Midbrain Tegmentum
-Tectum
Inferior Colliculi
-info from cochlear to superior colliculi and thalamus
-sound localization; integration of auditory info
Superior Colliculi
-motor and sensory info to orient head and eyes
-visual, auditorry, and somatosensory info
Basis Pedunculi
-Cerebreal peduncles (motor tracts from cortex)
-Substantia Nigra
Midbrain Tegmentum
-ascending tracts
-superior cerebellar peduncle
-red nucleus
-pedunculoponttine nucleus
-CN III and IV
-periaqueductal grey
Pons
-anterior wall of 4th ventricle; anterior to cerebellum
-most ascending tracts pass without synapsing (except corrticopontitne and corticobrainstem)
-Basilar
-Tegmentum
Pons Basilar Division
-descending tracts
-pontine nuclei
-pontocerebellar
Pons Tegmentum Divison
-ascending tracts
-reticular formation
-CN V-VIII nuclei
Upper Medulla
-most CN nuclei
-spinal trigeminal
-inferior olivary nucleus
Inferior Olivary Nucleus
-motor learning, timing, and conttrol of ongoing mmts
-info from cortical and SC then prroject to cerebellum
Lower Medulla
-decussation
-asending tracts pastt posteriorly
Midbrain CN
-III
-IV
Pons CN
-V
-VI
-VII
-VIII
Medulla CN
-IX
-X
-XI
-XII
Brainstem Blood Supply
-Vertebral A.
-ASA
-PICA
-Basilar
-AICA
-SCA
-PCA
-Pontiene
-Internal auditory A.
Midbrain Blood Supply
-PCA
-Basilar A.
Pons Blood Supply
-Basilar
-Pontiene
-AICA
Medulla Blood Supply
-ASA
-PICA
Brainstem Funcion
-Tracts (lesion: sensory and motor loss both ipsi and contra)
-CN function (lesion: ipsi facial issues)
-Consiousness (RAS, Reticular Formation)
-Vital sign regulation (Leison: BP fluctuation, breathing issues, HR issues)
4Ds of Brainstem Dysfunction
-dysphagia (swallowing)
-Dysarthria (motor production)
-Diplopia (double vision)
-Dysmetria (lack of coordination)
Anteromedial Midbrain Syndrome
-Weber’s Syndrome
-blockage of PCA or Basilar A. (midbrain branches)
Corticospinal: hemiparesis
Occulomotor: ipsi impaired eye mmts
Red nucleus: ataxia; emotional control
Lateral Inferior Pontine Syndrome
-occulsion of AICA; 2nd most common BS stroke
-affects pons
CN VIII Cochlear: ipsi hearling loss
CN VIII Vestib): dysequilibrium; nausea
Horner’s Syndrome: ipsi
CN V: ipsi facial pain
CN VII: decreased tears/saliva; ipsi weakness in face
Antetrolateral Spinothalamic: contra sensation
Bell’s Palsy
-CN VII damage
-flaccidity in ipsi hemiphere of face
-affects upper and lower (cortical is either or)
Horner’s Syndrome
-contricted pupils
-eyelid droop
-dry skin
-SNS issue
Locked-In Syndrome
-basilar artery throombosis or stenosis affecting ventral pons
Lost
Bilat Corticospinal: paralysis
Bilat Corticobulbar: face paralysis
Bilatt Abducens: not lat eye mmt
Spared
-RAS, vertical gaze
-mimic coma
Medial Medullary Syndrome
-ASA blockage
CN XII: ipsi tongue protrusion
DCML tract: contra loss of sensation
Corticospinal: contra hemiparesis
Lateral Medullar Syndrome
-Wallenberg’s
-Blockage of PICA; mostt common BS stroke
Solitary Nucleus: increase HR
Vestibular Nucleus: balance issues
Vagus N: Increased HR
Trigeminal: facial sensation
Inferior Cerebellar Peduncle: ataxia, coordination
Salivatory nucleus: saliva and tears, dental hygiene
Spinothalamic: contra pain and temp
Descending SNS: ipsi horner’s
Nucleus Ambiguous: swallowing, gag reflex, hoarseness
Mammillary Bodies
-recollective memory
Inferior Olive
-learning and timing of movements and comparing them to intended movements
Middle Cerebellar Peduncle
-connects cerebellum to pons
-largest
- contains afferent fibers
Inferior Colliculus
-sound localization
-pitch discrimination
-integration of auditory information
Superior Colliculus
-visual (directing eye movements), auditory, and somatosensory spatial information integration
Substania Nigra
-production of dopamine
-body movements
-part of basal ganglia
-on midbrain
Cerebral Peduncles
-refining fine motor movements
conversion of proprioceptive information into balance and posture
Inferior Olivary Nucleus
-coordinate signals from SC to cerebellum to regulate coordination
Periaqueductal Grey Matter
-modulation and propagation of pain
Thalamus
-interprets sensation information and perceives it
