Download Modules28-14to28-20

BIOLOGY
CONCEPTS & CONNECTIONS
Fourth Edition
Neil A. Campbell • Jane B. Reece • Lawrence G. Mitchell • Martha R. Taylor
CHAPTER 28
Nervous Systems
Modules 28.14 – 28.20
From PowerPoint® Lectures for Biology: Concepts & Connections
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
THE HUMAN BRAIN
28.14 The vertebrate brain develops from three
anterior bulges of the neural tube
• The vertebrate brain evolved by the
enlargement and subdivision of three anterior
bulges of the neural tube
– Forebrain
– Midbrain
– Hindbrain
• Cerebrum size and complexity in birds and
mammals correlates with sophisticated
behavior
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Embryonic
Brain Regions
Brain Structures
Present in Adult
Cerebrum (cerebral hemispheres; includes
cerebral cortex, white matter, basal ganglia)
Forebrain
Diencephalon (thalamus, hypothalamus,
posterior pituitary, pineal gland)
Midbrain
Midbrain (part of brainstem)
Pons (part of brainstem), cerebellum
Hindbrain
Medulla oblongata (part of brainstem)
Diencephalon
Cerebral
hemisphere
Midbrain
Midbrain
Pons
Cerebellum
Hindbrain
Medulla
oblongata
Spinal cord
Forebrain
Embryo one month old
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Fetus three months old
Figure 28.14
28.15 The structure of a living supercomputer:
The human brain
Table 28.15
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Cerebrum
Forebrain
Thalamus
Cerebral
cortex
Hypothalamus
Pituitary gland
Midbrain
Pons
Hindbrain
Medulla
oblongata
Spinal cord
Cerebellum
Figure 28.15A
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• Most of the cerebrum’s integrative power
resides in the cerebral cortex of the two cerebral
hemispheres
Left cerebral
hemisphere
Corpus
callosum
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Right cerebral
hemisphere
Basal
ganglia
Figure 28.15B
28.16 The cerebral cortex is a mosaic of
specialized, interactive regions
• The motor cortex sends commands to skeletal
muscles
• The somatosensory cortex receives information
about pain, pressure, and temperature
• Several regions receive and process sensory
information (vision, hearing, taste, smell)
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• The association areas are the sites of higher
mental activities (thinking)
– Frontal association area (judgment, planning)
– Auditory association area
– Somatosensory association area (reading,
speech)
– Visual association area
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FRONTAL LOBE
PARIETAL LOBE
Speech
Frontal
association
area
Taste
Somatosensory
association
area
Reading
Speech
Hearing
Smell
Auditory
association
area
Visual
association
area
Vision
TEMPORAL LOBE
OCCIPITAL LOBE
Figure 28.16
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• In lateralization, areas in the two hemispheres
become specialized for different functions
– “Right-brained” vs. “left-brained”
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28.17 Connection: Injuries and brain operations
have provided insight into brain function
• Much knowledge about
the brain has come from
individuals whose
brains were altered
through injury, illness,
or surgery
– The rod that pierced
Phineas Gage’s skull
left his intellect intact
but altered his
personality and
behavior
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Figure 28.17A
• A radical surgery called
hemispherectomy
removes almost half of
the brain
– It demonstrates the
brain’s remarkable
plasticity
Figure 28.17B
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28.18 Several parts of the brain regulate sleep and
arousal
• Sleep and arousal
are controlled by
– the hypothalamus
– the medulla
oblongata
– the pons
– neurons of
reticular
formation
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Eye
Reticular formation
Input from touch,
pain, and temperature
receptors
Input from
ears
Motor
output to
spinal cord
Figure 28.18A
• An electroencephalogram (EEG) measures
brain waves during sleep and arousal
• Two types of deep sleep alternate
– Slow-wave (delta waves) and REM sleep
Awake but quiet (alpha waves)
Awake during intense mental activity (beta waves)
Delta waves
Asleep
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REM sleep
Delta waves
Figure 28.18B, C
28.19 The limbic system is involved in emotions,
memory, and learning
• The limbic system is a functional group of
integrating centers in the cerebral cortex,
thalamus, and hypothalamus
• It is involved in emotions, memory (short-term
and long-term), and learning
– The amygdala is central to the formation of
emotional memories
– The hippocampus is involved in the formation of
memories and their recall
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Thalamus
CEREBRUM
Hypothalamus
Prefrontal
cortex
Smell
Olfactory
bulb
Amygdala
Hippocampus
Figure 28.19
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28.20 The cellular changes underlying memory and
learning probably occur at synapses
• Memory and learning involve structural and
chemical changes at synapses
– Long-term depression (LTD)
– Long-term potentiation (LTP)
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1 Repeated
Sending
neuron
action
potentials
Sending
neuron
Synaptic
cleft
2
2
4
3 Ca2+
Receiving neuron
Cascade of
chemical changes
Ca2+
3
LTP
Figure 28.20
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