Download Lecture 3

Anatomy of the
Central Nervous
System
Lecture 3
Telencephalon - Cortex
Gray Matter
 Somas and Dendrites
 Neocortex - 6 layers




Sensory input ---> layer IV
Motor output ---> layer V
Paleocortex - 2 or 3 layers ~
Telencephalon - Fiber Systems
White Matter - myelinated axons
 3 types of fiber systems
Commissural

Association
Projection ~
Commissural Fibers

Interconnect homologous structures in
the two hemispheres
 Corpus Callosum
 Anterior and Posterior
 Hippocampal ~
Anterior
Anterior



Association Fibers
interconnect cortical areas within
each hemisphere
Projection Fibers
all other fiber systems
 Fornix
 Corticospinal tract
 Mammillothalamic tract
Naming convention ~
Hemispheres
Left
Right
Association
Commissural
Projection
The Limbic System
Emotion
 Learning & Memory
 Structures
 Thalamus
 Hypothalamus
 Hippocampus
 Cingulate gyrus
 Amygdala
 Fornix ~

Limbic System
Cingulate gyrus
Hippocampus
Fornix
Thalamus
Hypothalamus
Amygdala
Basal Ganglia

Extrapyramidal Motor System
 Caudate
Striatum
 Putamen
Lenticular
 Globus Pallidus
Nucleus


Claustrum
Amygdala
no motor function ~
Caudate
Globus
pallidus
Putamen
Amygdala
Claustrum
Diencephalon
Surrounds third ventricle
 Thalamus
sensory and motor relay nuclei
 Hypothalamus
motivation & emotion ~

Thalamus
Lateral Geniculate Nuclei - LGN
vision
 Medial Geniculate Nuclei - MGN
audition
 Ventroposterior Nuclei - VPL & VPM
somatosensation
 Massa Intermedia - crosses midline ~

Hypothalamus

4Fs
feeding

fighting
fleeing, and ...
mating
Controls the pituitary gland ~
Diencephalon: thalamus
Massa
Intermedia
MGN
LGN
Diencephalon
Hypothalamus
Pituitary Stalk
Mesencephalon
Surrounds cerebral aqueduct
 Tectum
 Superior Colliculi - vision
 Inferior Colliculi - audition
 Tegmentum

Thalamus
Tectum
Superior
Colliculi
Inferior
Colliculi
Tegmentum
Periaqueductal Gray - pain
 Reticular Formation - sleep and
arousal, attention
 Red Nucleus and Substantia Nigra motor system
 Ventral Tegmental Area - VTA reinforcement

Cross-section of Tegmentum
PAG
Substantia
Nigra
Ventral
Tegmental
Area
Dorsal
Reticular
formation
Red
Nucleus
Metencephalon
Surrounds fourth ventricle
 Cerebellum
 coordinates movements
 Pons
 Sleep and arousal
 Reticular formation ~

Cerebellum
Pons
Myelencephalon
Medulla “Vital
Centers”
 Reticular
formation

Thalamus
Medulla
Spinal Cord
Gray
Matter
Dorsal
White
Matter
Central
Canal
Ventral
Spinal Cord
Dorsal
Horns
Dorsal
Lateral
Ventral
Ventral
Spinal cord
Dorsal horn - sensory input
 Lateral horn - autonomic N.S.
 Ventral horn - motor output ~
