Human Anatomy, Larry M. Frolich, Ph.D.

NERVOUS SYSTEM I

CNS (Central Nervous System)

Segmentation

PNS (Peripheral Nervous System)

Spinal Nerves

Neuron Types

Autonomic Nervous System

(how many nervous systems are there anyways?)

Human Anatomy, Larry M. Frolich, Ph.D.

Central Nervous System (CNS)

Brain and Spinal Cord

“Command Central”

PNS (Peripheral Nervous System) are nerves that go out to targets in body

Human Anatomy, Larry M. Frolich, Ph.D.

Coronal Section Cartoon

Brain Cranial Cavity of Skull Spinal Cord Vertebral Arches Cranial Nerves I-XII (off brain) Spinal Nerves C--8 prs (L,R) T--12 prs L--5 prs S--5 prs

Human Anatomy, Larry M. Frolich, Ph.D.

Counting Body Segments(vertebrae versus nerves)

Why are there seven cervical vertebrae but eight cervical nerves?

Human Anatomy, Larry M. Frolich, Ph.D.

Transverse View (x-section)

vertebral body

vertebral arch

vertebral foramen

spinal cord

Human Anatomy, Larry M. Frolich, Ph.D.

Sagittal View

vetebral body, arch

intervertebral disc

spinal cord

spinal nerves (where?)

Human Anatomy, Larry M. Frolich, Ph.D.

Zebra-Man

Dermatomes

Each is sensory area of one spinal nerve

Human Anatomy, Larry M. Frolich, Ph.D.

Peripheral Nervous System (PNS)

All nerves that leave the CNS Two Modalities:

SomaticVisceral/Autonomic

Sensory/Afferent(info. In)

Motor/Efferent(commands out)

SomaticVisceral/Autonomic

--smooth mm.--heart--glands

(hin

t: S

AM

E)

Par

asym

path

etic

Sym

path

etic

Human Anatomy, Larry M. Frolich, Ph.D.

Somatic Motor Neuron

(PNS)(CNS)

Human Anatomy, Larry M. Frolich, Ph.D.

Sensory Neuron

(PNS)(CNS)

Human Anatomy, Larry M. Frolich, Ph.D.

Visceral (Autonomic) Motor Neuron

(PNS)(CNS)

Human Anatomy, Larry M. Frolich, Ph.D.

Segmental Spinal nerve(more in Nervous System II)

Human Anatomy, Larry M. Frolich, Ph.D.

Autonomic “Targets”

All have dual sympathetic and parasympathetic innervation

(more in N.S.II)