1. Scientists map activity within the human brain
Figure 49.1 How?
For the Discovery Video Novelty Gene, go to Animation and Video Files.

2. Nervous system organization
Eyespot
Brain
Brain
Radial
nerve
Nerve
cords
Nerve
ring
Ventral
nerve
cord
Transverse
nerve
Nerve net
Segmental
ganglia
(a) Hydra (cnidarian)
(b) Sea star (echinoderm)
(c) Planarian (flatworm)
(d) Leech (annelid)
Brain
Brain
Ganglia
Ventral
nerve cord
Anterior
nerve ring
Brain
Spinal
cord
(dorsal
nerve
cord)
Sensory
ganglia
Longitudinal
nerve cords
Figure 49.2
Ganglia
Segmental
ganglia
(e) Insect (arthropod)
(f) Chiton (mollusc)
(g) Squid (mollusc)
(h) Salamander (vertebrate)

3. Spinal cord knee-jerk Reflex Cell body of Gray sensory neuron in
dorsal root
ganglion
Gray
matter
Quadriceps
muscle
White
matter
Hamstring
muscle
Figure 49.3 The
Spinal cord
(cross section)
Sensory neuron
Motor neuron
Interneuron

4. Vertebrate Nervous System
Central nervous
system (CNS)
Peripheral nervous
system (PNS)
Brain
Cranial
nerves
Spinal cord
Ganglia
outside
CNS
Spinal
nerves
Figure 49.4 The vertebrate nervous system

5. Ventricles, gray matter, and white matter
Figure 49.5

6. Glia in the vertebrate nervous system
CNS
PNS
VENTRICLE
Neuron
Astrocyte
Ependy-
mal
cell
Oligodendrocyte
Schwann cells
Microglial
cell
Capillary
(a) Glia in vertebrates
50 µm
Glia in the vertebrate nervous system
Figure 49.6
(b) Astrocytes (LM)

7. peripheral nervous system
PNS
Efferent
neurons
Afferent
(sensory) neurons
Motor
system
Autonomic
nervous system
Hearing
Sympathetic
division
Parasympathetic
division
Enteric
division
Locomotion
Figure 49.7 Functional hierarchy of the
Hormone
action
Gas exchange
Circulation
Digestion

8. Promotes ejaculation and
PNS:
autonomic nervous system
Parasympathetic division
Sympathetic division
Action on target organs:
Action on target organs:
Constricts pupil
of eye
Dilates pupil
of eye
Inhibits salivary
gland secretion
Stimulates salivary
gland secretion
Sympathetic
ganglia
Constricts
bronchi in lungs
Relaxes bronchi
in lungs
Cervical
Slows heart
Accelerates heart
Stimulates activity
of stomach and
intestines
Inhibits activity
of stomach and
intestines
Thoracic
Stimulates activity
of pancreas
Inhibits activity
of pancreas
Stimulates glucose
release from liver;
inhibits gallbladder
Stimulates
gallbladder
Figure 49.8 The parasympathetic and sympathetic divisions of the
Lumbar
Stimulates
adrenal medulla
Promotes emptying
of bladder
Inhibits emptying
of bladder
Promotes erection
of genitals
Sacral
Promotes ejaculation and
vaginal contractions
Synapse

9. Table 49.1

10. Development of the human brain
Cerebrum (includes cerebral cortex, white matter,
basal nuclei)
Telencephalon
Forebrain
Diencephalon
Diencephalon (thalamus, hypothalamus, epithalamus)
Midbrain
Mesencephalon
Midbrain (part of brainstem)
Metencephalon
Pons (part of brainstem), cerebellum
Hindbrain
Myelencephalon
Medulla oblongata (part of brainstem)
Cerebrum
Diencephalon:
Mesencephalon
Hypothalamus
Metencephalon
Thalamus
Midbrain
Pineal gland
(part of epithalamus)
Hindbrain
Diencephalon
Myelencephalon
Figure 49.9
Brainstem:
Midbrain
Pons
Spinal cord
Pituitary
gland
Forebrain
Medulla
oblongata
Telencephalon
Spinal cord
Cerebellum
Central canal
(a) Embryo at 1 month
(b) Embryo at 5 weeks
(c) Adult

11. Brainstem

12. Reticular Formation Eye Input from nerves of ears Reticular formation
Figure The
Input from nerves
of ears
Reticular formation
Input from touch,
pain, and temperature
receptors

13. Cerebellum

14. Diencephalon

15. Cerebrum

16. Human Brain viewed from the rear
Left cerebral
hemisphere
Right cerebral
hemisphere
Thalamus
Corpus
callosum
Basal
nuclei
Cerebral
cortex
Figure The human brain viewed from the rear

17. human cerebral cortex Frontal lobe Parietal lobe Motor cortex
Somatosensory cortex
Somatosensory
association
area
Speech
Frontal
association
area
Taste
Reading
Speech
Hearing
Visual
association
area
Smell
Auditory
association
area
Figure The
Vision
Temporal lobe
Occipital lobe

18. Body part representation in primary motor and primary somatosensory cortices
Frontal lobe
Parietal lobe
Shoulder
Upper arm
Elbow
Trunk
Knee
Head
Neck
Trunk
Hip
Leg
Forearm
Hip
Wrist
Elbow
Forearm
Hand
Hand
Fingers
Fingers
Thumb
Thumb
Eye
Neck
Nose
Brow
Face
Eye
Lips
Genitals
Toes
Face
Figure Body part representation in the primary motor and primary somatosensory cortices
Teeth
Gums
Jaw
Lips
Jaw
Tongue
Tongue
Pharynx
Primary
motor cortex
Primary
somatosensory cortex
Abdominal
organs

19. The limbic system Thalamus Hypothalamus Prefrontal cortex Olfactory
Figure 49.18
For the Discovery Video Teen Brains, go to Animation and Video Files.
Olfactory
bulb
Amygdala
Hippocampus

20. Effects of addictive drugs on the reward pathway of the mammalian brain
Nicotine
stimulates
dopamine-
releasing
VTA neuron.
Opium and heroin
decrease activity
of inhibitory
neuron.
Cocaine and
amphetamines
block removal
of dopamine.
Figure 49.22
Cerebral
neuron of
reward pathway
Reward
system
response

21. Microscopic signs of Alzheimer’s disease
Amyloid plaque
Neurofibrillary tangle
Figure 49.23

22. Human Brain Cerebral cortex Cerebrum Thalamus Forebrain Hypothalamus
Pituitary gland
Midbrain
Pons
Spinal
cord
Medulla
oblongata
Hindbrain
Cerebellum

23. You should now be able to:
Compare and contrast the nervous systems of: hydra, sea star, planarian, nematode, clam, squid, and vertebrate.
Distinguish between the following pairs of terms: central nervous system, peripheral nervous system; white matter, gray matter; bipolar disorder and major depression.
List the types of glia and their functions.
Compare the three divisions of the autonomic nervous system.

24. Describe the structures and functions of the following brain regions: medulla oblongata, pons, midbrain, cerebellum, thalamus, epithalamus, hypothalamus, and cerebrum.
Describe the specific functions of the brain regions associated with language, speech, emotions, memory, and learning.

25. Describe the symptoms and causes of schizophrenia, Alzheimer’s disease, and Parkinson’s disease
Explain how drug addiction affects the brain reward system