Download body and behavior

CHAPTER 6:
BODY AND
BEHAVIOR
HOW THE NERVOUS
SYSTEM WORKS
• Divided into 2 parts:
• 1) Central Nervous
System: brain and
spinal cord; nerves that
run up and down the
length of the back and
transmit most messages
between brain and
body
• 2) Peripheral NS: nerves
branching out from the
spinal cord
NEURONS
• Def: the long, thin cells
of nerve tissue along
which messages travel
to and from the brain
• Use chemical-electrical
signals
• All-or-none principle:
neuron either fires or
does not
BASIC PARTS OF A
NEURON
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3 basic parts:
1) Cell Body: contains nucleus
and produces energy for
activity
2) Dendrites: short, thin fibers
branching out from cell body;
receive impulses from other
neurons
3) Axon: long fiber that carries
impulses from cell body
Myelin sheath: white, fatty
substance that insulates
axons
Axon terminals: branch out
from end of axon; send msgs
to next neuron
NEURON
CONNECTION
• Synapse: the gap that
exists between
individual nerve cells
• Neurotransmitters:
chemicals released by
neurons, which
determine the rate at
which other neurons
fire
• Lock and key principle:
specific NTs will excite
or inhibit the next
neuron
NEUROTRANSMITTERS
Norepinephrine: involved in memory and learning
Endorphin: inhibits pain (analgesia)
Acetylcholine: movement and memory
Dopamine: learning, emotional arousal, movement
Serotonin: appetite, sleep, memory/learning, mood
Gamma amino butyric acid (GABA): muscle tone;
tied to anxiety
• Glutamate: excitatory relative of GABA; tied to ALS
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NEURON ACTIVITY
• Afferent neurons:
sensory neurons; bring
msgs from sense organs
to the brain
• Efferent neurons: motor
neurons; send msgs
from brain to glands
and muscles
• Interneurons: carry
impulses between
neurons
VOLUNTARY AND
INVOLUNTARY
• Somatic Nervous
System (SNS): part of
Peripheral NS that
controls voluntary
movement of skeletal
muscles
• Autonomic Nervous
System (ANS): Part of
PNS that controls
internal biological
functions
AUTONOMIC NERVOUS
SYSTEM
• Split into 2 parts:
• 1) Sympathetic Nervous
System: part of ANS
that prepares the body
for strenuous activities
• 2) Parasympathetic
Nervous System: part of
ANS that conserves
energy to recover from
strenuous activity
SECTION 2: STUDYING
THE BRAIN
You all have fat heads!
HINDBRAIN
• Def: part of the brain
located at the rear base
of the skull that is involved
in the basic processes of
life
• Cerebellum: posture,
balance, voluntary
movements
• Medulla: breathing, heart
rate, various reflexes
• Pons: connects spinal
cord and brain
MIDBRAIN
• Def: small part of the
brain above the Pons
that integrates sensory
info and relays it
upwards
• Medulla, pons, and
midbrain make up
brain stem
• Reticular Activating
System: alerts brain to
incoming signals
FOREBRAIN
• Def: part of the brain that
covers the brain’s central
core
• Thalamus: integrates
sensory info
• Hypothalamus: 4-Fs—
fight, flight, feeding,
sexual behavior
• Cerebral cortex: outer
layer; learning, abstract
thought, conscious
thought, personality
• Cerebrum: inner layer,
covered by cortex
LIMBIC SYSTEM
• Part of Forebrain
• Hypothalamus
• Amygdala: violent
emotions
• Thalamus
• Hippocampus:
formation of memories
LOBES OF THE BRAIN
• Lobe: different regions
into which the cerebral
cortex is divided
• Occipital Lobe: back of
brain; vision
• Parietal Lobe: back top;
body senses
• Temporal Lobe: sides;
hearing, memory,
emotion, speaking
• Frontal Lobe: front top;
organization, planning,
creative thought
LEFT AND RIGHT
HEMISPHERES
• Connected by corpus
callosum
• Not separate---they
complement each
other
HEMISPHERE ACTIVITY
LEFT BRAIN
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Right side of the body
Speech
Math
Logic
Calculation
RIGHT BRAIN
• Left side of the body
• Visual and spatial
relationships
• Perceptual tasks
• Creativity
• Intuition
SPLIT-BRAIN
OPERATIONS
• Used to treat severe
epilepsy
• Helps stop grand mal
seizures
• Operation: sever
corpus callosum
• Shows unique functions
of each hemisphere
HOW PSYCHOLOGISTS
STUDY THE BRAIN
RECORDING
• Electrodes measure
electrical activity in the
brain
• Electroencephalograph
(EEG): machine used to
record electrical
activity of large
portions of the brain
STIMULATION
• Applying electrical
current to specific
locations in the brain
• Can trigger smells,
sounds, sights,
emotions, memories, or
control pain
LESIONS
• Cutting or destroying a
part of the brain to
study effects
• Mostly on animals
ACCIDENTS
• Random
• Phineas Gage--located personality
• Dr. Pierre Paul Broca--speech production
IMAGES
• Computerized Axial
Tomography (CAT): used to
pinpoint injuries and
deterioration
• Positron Emission
Tomography (PET): used to
see which areas are being
activated while performing
tasks
• Magnetic Resonance
Imaging (MRI): used to study
brain structure and activity
• Functional MRI (fMRI):
observe both function and
structure
SECTION 3: THE
ENDOCRINE SYSTEM
ENDOCRINE SYSTEM
• Def: a chemical
communication system
using hormones, by
which msgs are sent
through the
bloodstream
• Hormones: chemical
substances that carry
msgs through the body
in blood
PITUITARY GLAND
• Def: the center of
control of the
endocrine system;
secretes large amts of
hormones
• “Master Gland”
• Monitors hormone
levels in blood and
corrects imbalances
THYROID GLAND
• Produces thyroxine to
stimulate tissues
• Hypothyroidism: too
little thyroxine; lethargy
• Hyperthyroidism: too
much thyroxine;
overactive
ADRENAL GLANDS
• Activate when angry or
scared
• Release epinephrine
(adrenaline) and
norepinephrine
• Releases cortical
steroids to develop
muscles
SEX GLANDS
• Testes: male; produce
testosterone
• Ovaries: female;
produce estrogen and
progesterone
HORMONES VS.
NEUROTRANSMITTERS
• Hormones used for
slower, more
widespread
communication
• NTs used for rapid,
specific msgs
SECTION 4: HEREDITY
AND ENVIRONMENT
Genes establish what you could be and the environment
defines the final product…
HEREDITY
• Def: the genetic
transmission of
characteristics from
parents to their
offspring
• Sir Francis Galton:
Hereditary Genius
(1869)---started nature
vs. nurture debate
• John Watson
emphasized
environment
TWINS
• Identical twins: twins
who come from one
fertilized egg; have the
same heredity
(monozygotic)
• Genes: basic building
blocks of heredity
• Fraternal twins: twins
who come from 2
different eggs fertilized
by 2 different sperm
(dizygotic)
TWIN STUDIES
• Identical twins are
preferable
• Studying Iden. twins
separated at birth gives
good indications of
what is genetic and
what is environment