4 - NeuroAnatomy Internal Organization Flashcards
Cingulate Gyrus
Emotional Valence on Sensory and Motor Activity
Contiguous with Parahippocampal Gyrus
Lateral Ventricles
1 in each hemisphere, C-shaped
Third Ventricle
Diencephalon, Thalamus and Hypothalamus form lateral borders
Connection between Lateral Ventricle and Third Ventricle
Foramen of Monroe
3 Horns of the Lateral Ventricles
Anterior Horn (contains the “body” of the ventricle)
Posterior Occipital Horn
Inferior Horn
Basal Ganglian
Subcortical group of nuclei important for initiation and selection of movement, etc
Putamen
Most lateral compnent of the Basal Ganglion
Internal Capsule
Fibers going up to and down from the cortex
Caudate
Forms the lateral border of most of the lateral ventricle
Tail goes into temporal lobe
Fornix
Comes off of each Hippocampal Formation in each hemisphere.
Hemispheres join together and form the body, directly under the Corpus Callosum.
Runs rostrally to the Anterior Commissure
Descends ventrally and laterally to form the Mammilary Body
Mammilary Body
The ends of the Fornix
Amygdala
Most rostral nucleus in Temporal Lobe
Emotion, especially fear
Anterior Commisure
The point at which the body of the Fornix splits to form two Mammilary Bodies
2 Major Groups of Nuclei in the Temporal Lobe
Amygdala
Hippocampal Formation
Hippocampal Formation
Caudal to the Amygdala in the Temporal Lobe
Memory Consolidation
3 Classes of Fibers in the Brain
Commissures
Projection Fibers
Association Fibers
Commissures
Corpus Callosum
Anterior Commissure
Posterior Commissure
Connect homotypic (functionally-related) regions of the two cerebral hemispheres
Projection Fibers
Corticospinal Tract (Motor Cortex to Spinal Cord) Interconnect a source in the cortex with a distant subcortical target (run in the internal capsule)
Association Fibers
Extreme Capsule
External Capsule
Interconnect cortical regions in the same hemisphere
Splenium
Most caudal part of the Corpus Callosum
Steps in interpreting Coronal and Horizontal brain sections
Identify ventricles
Identify structures bordering ventricles
Identify and follow internal capsule from cortex to medulla
Identify structures bordering internal capsule at each level
Roof of Lateral Ventricle
Corpus Callosum
Walls of Lateral Ventricle
Caudate Nucleus (Lateral) Septum Pellucidum (Medial)
Floor of Lateral Ventricle
Hippocampal Formation / Fornix
Walls of Third Ventricle
Diencephalon (Thalamus, Hypothalamus)
Borders of Cerebral Aqueduct
Tectum of Midbrain (Superior and Inferior Colliculi)
Tegmentum of Midbrain
Borders of Fourth Ventricle
Cerebellum, Pons, Medulla
Medial wall of the Lateral Sulcus
Insular Cortex
Insular Cortex functions
Taste, pain, other sensory stuff
Cingulate Sulcus
A lateral sulcus off of the Sagittal Sulcus
Cingulate Gyrus
Just inferior to the cingulate sulcus
Putamen + Caudate together
Striatum
Anterior Commissure
Carries information from Olfactory Cortex to the Amgydala and other stuff in the temporal lobe
Infundibulum
Connects the Hypothalamus and the Pituitary
What sensory modality is delivered in the splenium?
Vision!!!!
Collateral Trigone or Atrium
Point at which Lateral Ventricle’s posterior and inferior horns meet and swell.
Roof of the Collateral Trigone / Atrium
Tail of the caudate
Internal Capsule
Anterior Limb - Fibers from the frontal lobe
Genu - Face
Posterior Limb - Arm, Trunk, Leg (progressing caudally)
Primary Visual Cortex
V1 or Broman’s Area 17
Calcarine Sulcus
Medial fissure on the caudal side of the brain.
Most outer layer of Spinal Cord
White Matter
Inner butterfly of Spinal Column
Grey Matter
Dorsal Horn of Spinal Cord function
Processing of sensory information
Ventral Horn of Spinal Cord function
Processing of motor information
Ascending rostrally from sacral to cervical, what happens to the amount of white matter?
It increases. As you ascend, more fibers are coming in, and fewer fibers are going out.
Where do you see enlargements in the ventral horn of the spinal cord?
Cervical, Lumbar, Sacral. These control the most motor thangs.
Motor Decussation
At the level of the Spinal Cord-Medulla Junction, descending projection fibers which synapse in the brainstem and the spinal cord CROSS to the opposite side
Pyramids (at the Spinal Cord-Medulla Junction)
Descending Cortical Fibers
Anything caudal to the Motor Decussation
Spinal Cord
Anything rostral to the Motor Decussation
Medulla
Central Canal
Ventricular portion of the Caudal Medulla and Spinal Cord
Sensory Decussation - Location
Rostral to Motor Decussation
Sensory Decussation - Contents
4 Dorsal Column Nuclei Medial Lemniscus Pyramids Central Canal Inferior Olivary Nucleus
Sensory Decussation - Pathway
Fibers from caudal synapse on Dorsal Column Nuclei, which then project to the opposite side.
Medial Lemniscus ascends.
Mid-Medulla - Contents
Cranial Nerve Nuclei Inferior Cerebellar Peduncle Reticular Formation Inferior Olivary Nucleus Medial Lemniscus Pyramids
3 Bundles of fibers carrying information into and out of the Cerebellum to/from the Mid-Medulla
Medial Lemniscus
Inferior Olivary Nucleus
Reticular Formation
Medial Lemniscus
Somatosensory ascending fibers from the Medulla to the Cerebellum
Inferior Olivary Nucleus
Clamshell-shaped bundle of neurons that project fibers through the Inferior Cerebellar Peduncle
Reticular Formation
Bundle of fibers in the Mid-Medulla controlling: Attention Arousal Visceral Functions Blood Pressure
Pons - Contents
Facial Colliculus
Pontine Nuclei
Facial Colliculus
Nucleus of VI & the Genu of VII -
Pontine Nuclei
Part of Pons involved in motor activity
Two Most Caudal bumps of Midbrain flanking the Cerebral Aqueduct
Inferior Colliculi
Inferior Colliculi
Obligatory relay stations for audition in the Midbrain
Basis Pedunculi
Cerebral Peduncles - Descending motor fibers in the anterior Midbrain. Once we reach the Medulla, they become the Pyramids.
Corpora Quadrigemina
Four Colliculi on the Tectum of the dorsal aspect of the midbrain:
Reflex Centers involving Vision and Hearing
Tectum
The uppermost part of the midbrain, lying dorsal to the cerebral aqueduct
Substantia Nigra
Descending motor fibers just posterior to the Basis Pedunculi
Decussation of the Superior Cerebellar Peduncle - Location on Imaging
At the level of the Inferior Colliculi, anterior to the Cerebral Aqueduct
Midbrain Contents - Level of the Superior Colliculi
Superior Colliculi
Substantia Nigra
Red Nucleus
III Fascicles into Interpeduncular Fossa
Lesion on Substantia Nigra leads to
Parkinson’s
What landmark can you see at the Superior Colliculi, but not the Inferior Colliculi?
Red Nuclei
Space between the two Basis Pedunculi (at level of Superior Colliculi)
Interpeduncular Fossa
