Brain Stem I
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Brain Stem I Brain Stem I Basic Neuroscience Basic Neuroscience James H. Baños, Ph.D. James H. Baños, Ph.D.
description
Brain Stem I. Basic Neuroscience James H. Baños, Ph.D. Overview. Major external features Transverse sections Pathways: The big Four Neurotransmitter nuclei. Major Brain Stem Activities. Conduit Ascending and descending pathways Integrative functions Complex motor patterns - PowerPoint PPT Presentation
Transcript of Brain Stem I
Brain Stem IBrain Stem I
Basic NeuroscienceBasic Neuroscience
James H. Baños, Ph.D.James H. Baños, Ph.D.
OverviewOverview
Major external featuresMajor external features Transverse sectionsTransverse sections Pathways: The big FourPathways: The big Four Neurotransmitter nucleiNeurotransmitter nuclei
Major Brain Stem Major Brain Stem ActivitiesActivities
ConduitConduit Ascending and descending pathwaysAscending and descending pathways
Integrative functionsIntegrative functions Complex motor patternsComplex motor patterns Respiratory and cardiovascular activityRespiratory and cardiovascular activity Regulation of arousal and level of Regulation of arousal and level of
consciousnessconsciousness Cranial Nerve functionsCranial Nerve functions
Major External Major External FeaturesFeatures
Brain StemBrain Stem
Midbrain
Pons
Medulla
MidbrainMidbrain
Cerebral PedunclesCerebral Peduncles Interpeduncular cisternInterpeduncular cistern
Origin of CN III -- Oculomotor NerveOrigin of CN III -- Oculomotor Nerve
Corpora QuadrigeminaCorpora Quadrigemina Superior ColliculiSuperior Colliculi Inferior ColliculiInferior Colliculi
MidbrainMidbrainCorporaquadrigemina
Cerebralpeduncles
Interpeduncularcistern
CN III
PonsPons
Cerebellar PedunclesCerebellar Peduncles Superior (Dives under the colliculi)Superior (Dives under the colliculi) Middle (Bridge of the pons)Middle (Bridge of the pons) Inferior (inferior/medial to middle)Inferior (inferior/medial to middle)
Floor of the 4th VentricleFloor of the 4th Ventricle
PonsPons
PonsPons
Middle cerebellar peduncle
PonsPons
Middle cerebellar peduncle
Inferior cerebellar peduncles
Superior cerebellar peduncles
PonsPons
4th Ventricle4th Ventricle Inflow from aqueduct of Inflow from aqueduct of
SylviusSylvius Sulcus limitansSulcus limitans
MedullaMedulla
PyramidsPyramids Pyramidal decussationPyramidal decussation Inferior oliveInferior olive Obex (inferiormost point of the 4th Obex (inferiormost point of the 4th
ventricle)ventricle)
MedullaMedulla
Pyramids
Obex
Inferior olive
MedullaMedulla
Inferior Olive
Pyramids
Transverse Transverse SectionsSections
Transverse SectionsTransverse Sections
But first…a word about orientation…But first…a word about orientation…
Clinical Anatomical
MidbrainMidbrain
Cerebral pedunclesCerebral peduncles Substantia nigraSubstantia nigra Red nucleusRed nucleus
Midbrain = Mickey
MidbrainMidbrain
Cerebral peduncles
Myelin Stained
MidbrainMidbrain
Substantia nigra
MidbrainMidbrain
Red Nucleus
MidbrainMidbrain
Colliculi
MidbrainMidbrain
Substantia nigra
MidbrainMidbrain
Substantia nigra
Red nucles
PonsPons
4th ventricle4th ventricle Pontine nucleiPontine nuclei Locus ceruleusLocus ceruleus
PonsPonsPontine nuclei
4th vent
Locus ceruleus
PonsPons
Locus ceruleus
PonsPons
4th ventricle4th ventricle Pontine nucleiPontine nuclei Locus ceruleusLocus ceruleus
PonsPons
4th ventricle
Middle cerebellar peduncle
Sulcus Limitans
PonsPons
Rostral MedullaRostral Medulla
PyramidsPyramids Inferior OliveInferior Olive
Rostral MedullaRostral Medulla
PyramidsInferior olive
Caudal MedullaCaudal Medulla
Sensory nucleiSensory nuclei Nucleus GracilisNucleus Gracilis Nuclues CuneatusNuclues Cuneatus
Pyramidal decussationPyramidal decussation
Caudal MedullaCaudal Medulla
Nucleus cuneatusNucleus gracilis
Tectum and TegmentumTectum and Tegmentum
Tectum and TegmentumTectum and Tegmentum
TectumTectum Area posterior to the ventricular spaceArea posterior to the ventricular space Only prominent in the midbrainOnly prominent in the midbrain
Superior and inferior colliculi (“tectal Superior and inferior colliculi (“tectal plate”)plate”)
Tectum and TegmentumTectum and Tegmentum
Tectal Plate
Tectum and TegmentumTectum and Tegmentum TegmentumTegmentum
Area anterior to the ventricular space (but not Area anterior to the ventricular space (but not everything anterior)everything anterior)
This is the embryologically oldest areas of the This is the embryologically oldest areas of the brainstembrainstem
Area anterior to the tegmentum “added on” Area anterior to the tegmentum “added on” during developmentduring development
Big Four Big Four PathwaysPathways
Remember the Big Four?Remember the Big Four?
Corticospinal tract
Dorsal Columns
Spinothalamic tract
Spinocerebellar tracts
Big Four PathwaysBig Four Pathways Corticospinal tractCorticospinal tract
Descending motorDescending motor Spinothalamic tractSpinothalamic tract
Ascending pain/temperatureAscending pain/temperature Dorsal columns/Medial lemniscusDorsal columns/Medial lemniscus
Ascending somatosensory and conscious proprioceptionAscending somatosensory and conscious proprioception Spinocerebellar tractsSpinocerebellar tracts
Ascending unconscious proprioceptionAscending unconscious proprioception
The Big Four -- Caudal MedullaThe Big Four -- Caudal Medulla
Corticospinal tract
Medial Lemniscus
Spinothalamic tract
Spinocerebellar tracts
Lateral Cuneate Nucleus
The Big Four -- Rostral MedullaThe Big Four -- Rostral Medulla
Corticospinal tract
Medial Lemniscus
Spinothalamic tract
Spinocerebellar tracts
The Big Four…err…three -- PonsThe Big Four…err…three -- Pons
Corticospinal tract
Medial Lemniscus
Spinothalamic tract
The Big Three -- MidbrainThe Big Three -- Midbrain
Corticospinal tract
Medial Lemniscus
Spinothalamic tract
Brain Stem Brain Stem NucleiNuclei
Brain Stem NucleiBrain Stem Nuclei
Major neurotransmitter nucleiMajor neurotransmitter nuclei Reticular formation (not really a Reticular formation (not really a
“nucleus” but acts like a group of “nucleus” but acts like a group of nuclei)nuclei)
Nuclei associated with cranial Nuclei associated with cranial nervesnerves
Raphe NucleiRaphe Nuclei
Ridge of cells along the midline in Ridge of cells along the midline in the center of the brainstemthe center of the brainstem
Multiple nucleiMultiple nuclei Caudal Caudal
projections to the spinal cord and other projections to the spinal cord and other parts of the brainstemparts of the brainstem
Rostral Rostral projections to multiple cortical areasprojections to multiple cortical areas
Raphe NucleiRaphe Nuclei
Major serotonin nucleiMajor serotonin nuclei Technically part of the reticular formationTechnically part of the reticular formation Complex reciprocal relationships with multiple Complex reciprocal relationships with multiple
areasareas Ascending pathways involved in many Ascending pathways involved in many
neurobehavioral phenomenaneurobehavioral phenomena MoodMood SleepSleep Feeding/satietyFeeding/satiety
Descending pathways modulate spinal cord Descending pathways modulate spinal cord functionfunction PainPain
Locus CeruleusLocus Ceruleus
Major norepinephrine nucleusMajor norepinephrine nucleus Dorsal wall of the rostral ponsDorsal wall of the rostral pons Projects toProjects to
Spinal cordSpinal cord Brain StemBrain Stem CortexCortex
Locus CeruleusLocus Ceruleus
FunctionFunction ArousalArousal Modulation of stress responsesModulation of stress responses Linked toLinked to
DepressionDepression AnxietyAnxiety Post-traumatic stress disorderPost-traumatic stress disorder
Accounts for some of the psychiatric Accounts for some of the psychiatric symptoms in Parkinson’s Diseasesymptoms in Parkinson’s Disease
Locus CeruleusLocus Ceruleus
Normal Parkinson’s Disease
Substantia NigraSubstantia Nigra
One of a few major dopamine centerOne of a few major dopamine center Projects to the basal gangliaProjects to the basal ganglia FunctionFunction
Modulation of movementsModulation of movements Major role in Parkinson’s DiseaseMajor role in Parkinson’s Disease NOT involved in psychiatric NOT involved in psychiatric
symptomssymptoms
Substantia NigraSubstantia Nigra
Parkinson’s Disease Normal
Nucleus Basalis of Nucleus Basalis of MeynertMeynert
NOT in the brainstem, but importantNOT in the brainstem, but important Located in the basal forebrainLocated in the basal forebrain Major acetylcholine nucleus in the Major acetylcholine nucleus in the
brainbrain Provides tonic stimulation to the Provides tonic stimulation to the
hippocampushippocampus
Basal Forebrain
Nucleus Basalis of Nucleus Basalis of MeynertMeynert
Major neurotransmitter associated Major neurotransmitter associated with Alzheimer’s Diseasewith Alzheimer’s Disease
Major medications for Alzheimer’s Major medications for Alzheimer’s are cholinesterase inhibitorsare cholinesterase inhibitors
Coming Up…Coming Up…
Reticular formationReticular formation Cranial nerves and their nucleiCranial nerves and their nuclei
