Anatomy of theCentral Nervous System:

Forebrain

Lecture 5

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 ~

AnteriorAnterior

Association Fibers interconnect cortical areas within each

hemisphere Projection Fibers

• all other fiber systems Fornix Corticospinal tract Mammillothalamic tract

Naming convention ~

Association & Projection Fibers

Association

Commissural

Projection

HemispheresLeft Right

The Limbic System

Emotion Learning & Memory Structures

Thalamus Hypothalamus Hippocampus Cingulate gyrus Amygdala Fornix ~

Amygdala

Hippocampus

Limbic System

Thalamus

Hypothalamus

Cingulate gyrus

Fornix

Basal Ganglia

Extrapyramidal Motor System Caudate Putamen Globus Pallidus

Striatum

Lenticular Nucleus

Claustrum

Amygdala

no motor function ~

Caudate

AmygdalaPutamen

Globuspallidus

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

Control of behaviors critical to survival Feeding Fighting Fleeing Mating

Controls the pituitary gland ~

Thalamus

Diencephalon: thalamus

LGNMGN

MassaIntermedia

Diencephalon

HypothalamusPituitary Stalk