Transcript Mind, Brain & Behavior

Mind, Brain & Behavior
Wednesday
January 22, 2003
Discussion of Term Paper
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The goal is to integrate information about
brain and behavior with real-world
controversies.
Be sure to cover pros and cons, as well as
your own opinions.
Give credit to all sources and do not copy
from anyone.
Language use counts, but any format is OK.
The Nervous System
Chapter 4
Imaging Techniques
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Looking at brain structure:
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CAT scan – computer-assisted tomography
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Absorption of radiation
MRI – magnetic resonance imaging
Looking at brain functioning:
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PET scan – positron emission tomography
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Emission of radiation from sites absorbing an isotope
changing with metabolism
fMRI – functional MRI
Parts of the Nervous System
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Central Nervous System (CNS) – brain and
spinal cord
Peripheral Nervous System (PNS) – ganglia
and peripheral nerves outside the brain and
spinal cord.
Anatomically separate but functionally
interconnected – they work together.
Parts of the PNS
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Somatic – provides CNS with sensory
information.
Autonomic – the motor system for the viscera,
the smooth muscles, and the exocrine glands.
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Sympathetic – helps the body respond to stress.
Parasympathetic – restores the body to a resting
state
Enteric – controls the smooth muscle of the gut
Seven Main Parts of the CNS
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Spinal cord
Medulla – regulates blood pressure and
breathing
Pons – helps medulla
Cerebellum – planning, timing of movement
Midbrain – control of eye movement, relay
Diencephalon – thalamus & hypothalamus
Cerebral hemispheres – perception, cognition
Spinal Cord
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Receives sensory information and contains
neurons for voluntary and reflex muscle
movement.
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31 pairs of spinal nerves
Dorsal roots carry sensory information
Ventral roots carry outgoing motor axons and
axons of the sympathetic and parasympathetic
ANS
Ascending and descending pathways to brain.
Brain Stem
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Contains the medulla, pons and midbrain.
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Receives sensory information and controls
muscles of head, neck, face.
Involved with hearing, taste, balance.
Reticular formation mediates alertness and
attention.
Ascending and descending pathways to higher
brain regions.
Cerebral Cortex
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Outer layers of cortex – gray matter
Underlying myelinated axons and glial cells –
white matter
Clusters of related neurons – called nuclei:
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Basal ganglia
Hippocampus
Amygdala
Two hemispheres
Four Functional Lobes
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Frontal
Parietal
Temporal
Occipital
Two other areas:
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Insular cortex – inside the lateral sulcus
Limbic lobe – inside the four lobes overlying the
brain stem and diencephalon
Deep-Lying Structures
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Basal Ganglia – regulation of movement,
cognition.
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Receive input from all four lobes and
communicate to the frontal cortex via thalamus.
Hippocampus – forms memories
Amygdala – coordinates emotion, autonomic
and endocrine systems via hypothalamus.
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Hippocampus & amygdala are parts of limbic
system.
Four Organizational Principles
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Each system contains relay centers (nuclei).
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Relay nuclei contain local interneurons and
projection interneurons.
Thalamus – processes almost all sensory info
Each system has several distinct pathways.
Pathways are topographically organized.
Most pathways cross to the opposite side.
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Decussation
Systems Interact
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Textbook example: physical actions involve
sensory, motor and limbic (motivational)
systems.
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When systems interact, they must be
interconnected (see Figure 5-9)
Different senses have their own pathways
operating in parallel.
Information is combined (integrated) at some
point -- how this happens is an open question.