12-1

Nervous SystemCopyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Brain

Nerves

Ganglia

Peripheral nervoussystem (PNS)

Central nervoussystem (CNS)

Spinalcord

Figure 12.1

12-2

Functional Classes of NeuronsCopyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

1

2

3

Peripheral nervous system Central nervous system

Sensory (afferent)neurons conductsignals fromreceptors to the CNS.

Motor (efferent)neurons conductsignals from the CNSto effectors such asmuscles and glands.

Interneurons(associationneurons) areconfined tothe CNS.

Figure 12.3

14-3

Embryonic Brain DevelopmentCopyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Diencephalon

Mesencephalon

Telencephalon

Forebrain

Pons

CerebellumMetencephalon

Spinal cord

Hindbrain

Telencephalon

Optic vesicle

Diencephalon

Metencephalon

Myelencephalon

Spinal cord

Rhombencephalon

Mesencephalon

Prosencephalon

(a) 4 weeks (b) 5 weeks

(c) Fully developed

Midbrain

Myelencephalon(medulla oblongata)

Figure 14.4

leaves

Neural groove

Neural fold

(b) 20 days

(d) 26 days

Neural crest

Neuralcrest

Neuraltube

14-4

Brain Ventricles

Figure 14.6 a-b

Lateral ventricles

Fourth ventricle

Third ventricle

(a) Lateral view

Lateral ventricle

Third ventricle

Fourth ventricle

VentriclesVentriclesLateral

Third

Fourth

14-5

Directional Terms and Landmarks

14-6

Brainstem

Cerebellum

Cerebrum

Spinal cord

Rostral Caudal

(b) Lateral view

Gyri and Sulci

Gray Matter and White Matter

14-7

Cerebrum

14-814-8

Cerebrum-Frontal Lobe

14-9

Cerebrum-Parietal Lobe

14-10

Cerebrum-Occipital Lobe

14-11

Cerebrum-Temporal Lobe

14-12

14-13

Sensory and Motor areasCopyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

leavesPrecentral gyrus

Anterior Posterior

Auditorycortex

Postcentralgyrus

Primaryvisual cortex

Brocaarea

Figure 14.25

14-14

Limbic System

Basal nuclei

Temporal lobe

Fornix

Hippocampus

Corpuscallosum

Cingulategyrus Thalamic

nuclei

Cerebellum

14-15

Brainstem

14-16

diencephalon

midbrain

pons

medulla oblongata 14-16

Diencephalon

14-17

Thalamus Hypothalamus

Pituitary Gland

14-18

Pineal Gland

14-19