chapter 6 body & behavior. section 1 the nervous system
TRANSCRIPT
Chapter 6Body & Behavior
Section 1
The Nervous System
The Organization of the Nervous System
Nervous systemNervous system
Peripheral nervous Peripheral nervous systemsystem
Central nervous Central nervous system (CNS)system (CNS)
AutonomicAutonomicnervous systemnervous system
SomaticSomaticnervous systemnervous system
SympatheticSympatheticnervous systemnervous system
Parasympathetic Parasympathetic nervous systemnervous system
Two Divisions of the Nervous System
• Central Nervous System (CNS)– Made up of the brain and spinal cord.
• Peripheral Nervous System (PNS)– Nerves branching out from the
spinal cord.
Two Divisions of the PNS
• Somatic NS – controls voluntary behaviors
• Autonomic NS – controls involuntary behaviors
– Sympathetic – “fight or flight”
– Parasympathetic – “rest and digest”
The Neural Impulse
Synapse
- The gap between neurons.
Neurotransmitters
• Neurotransmitters – Chemical messengers that relay neural messages across the synapse.
ANIMATION
3 Types of Neurons:
-Sensory (afferent) neurons - carry messages from sense receptors towards the brain.
-Motor (efferent) neurons - carry messages from brain toward muscles and glands.
-Interneurons - carry messages between nerve cells.
Section 2
Studying the Brain
3 Parts of the Brain:
1. Forebrain
2. Midbrain
3. Hindbrain
Forebrain
• A part of the brain that covers the brain’s central core.
Includes:• Thalamus• Hypothalamus• Cerebral cortex• Cerebrum• Limbic system• Amygdala • Hippocampus
ForebrainThalamus
– Integrates sensory input; relay station for all the information that travels to and from the brain.
Hypothalamus– Controls functions such as hunger, thirst, and sexual
behavior; also controls temperature.
Cerebral cortex– Outer layer of the forebrain; gives you the ability to learn and
store complex and abstract information.
ForebrainCerebrum
– Inner layer of the forebrain.
Limbic system– Various structures in the brain that regulate our emotions
and motivations (includes: amygdala, hippocampus)
Midbrain
• A small part of the brain above the pons that integrates sensory information and relays it upward.
RAS:• Alerts the rest of the brain
to incoming signals and is involved in the sleep/wake cycle.
Hindbrain
• Located at the rear base of the skull; involved in the basic processes of life.
Includes:• Cerebellum• Medulla• Pons
Hindbrain
Cerebellum– Helps control posture, balance, and voluntary
movements.
Medulla– Controls breathing, heart rate, and other reflexes.
Pons– Produces chemicals the body
needs for sleep.
Parts of the Brain Parts of the Brain
• Thalamus
• Pons
• Cerebellum
• Medulla
• Brain stem
The 4 Lobes:Frontal lobe
(organization, planning, creative thinking)
Parietal lobe(touch sensations)
Occipital lobe
(visual signals)
Temporal lobe
(hearing, speaking)
Left v Right Hemisphere
Split-Brain Operations
• A treatment option for those suffering from grand mal seizures.
– Separating the brain hemispheres by severing the corpus callosum lessons the number and severity of seizures. Mr. Split-Brainy
Video
How do we study the BRAIN?
1. Recording (EEG)2. Stimulation3. Lesions4. Accidents - Phineas Gage5. Images
(CAT, PET, MRI)
Recording
• Electroencephalograph (EEG):– A machine used to record electrical activity in
the brain.
Stimulation
• Wilder Penfield stimulated the brains of his patients during surgery to determine what functions the various parts of the brain perform.
– He was able to localize the malfunctioning parts of the brain.
Lesions
• Lesions: cutting or destroying parts of the brain.
• If the animal behaves differently after the operation, we can assume the destroyed brain area is involved with that type of behavior.
Accidents
• Psychologists can learn about the brain when people are involved in accidents.
• Psychologists try to draw a connection between the damaged parts of the brain and a person’s behavior.
Accidents – Phineas Gage
• His frontal lobe was damaged, which caused his personality to change*
• He became short-tempered and said inappropriate things.
• Therefore, damage to the frontal lobe prevents censoring of thoughts and ideas.
Images
• CAT (computerized axial tomography)
– Used to pinpoint injuries in the brain.• PET (positron emission tomography)
– Used to see which brain areas are being activated while performing tasks.
• MRI (magnetic resonance imaging)
– Used to study brain structures.
Section 3
Copyright © Allyn & Bacon 2007
The Endocrine System(the body’s chemical messenger system)
Endocrine System - Glands
• Pituitary gland– Control center of the
endocrine system that secretes a large number of hormones.• Known as the master
gland.• Produces growth
hormones.
Video Clip - Gigantism
Endocrine System - Glands
• Thyroid gland– Produces the hormone
thyroxin.– Hypothyroidism – makes
people feel lazy and lethargic.
– Hyperthyroidism – causes people to lose weight and be overactive.
Endocrine System - Glands
• Adrenal glands– Release adrenaline into the bloodstream.
• Causes heart rate and breathing to increase• Heightens emotions (fear, anxiety)
Endocrine System - Glands
Sex glands:– Ovaries
• Produce eggs and the female hormones estrogen and progesterone.
– Testes• Produce sperm and
the male sex hormone testosterone.
Hormones vs NeurotransmittersHormones vs Neurotransmitters• Endocrine System
– Glands release hormones into the bloodstream.
• Nervous System– Neurons release
neurotransmitters to either excite or inhibit other neurons.
Section 4
Heredity & Environment
Heredity• The genetic transmission of
characteristics from parents to their offspring.
Nature v Nurture
• Nature– The characteristics a
person inherits– Biological makeup– GENETICS
Sir Francis Galton
• Nurture– ENVIRONMENT– Family, culture,
education, and individual differences
John Watson
Genes – the basic building blocks of heredity.
Twin Studies
• Identical twins– Come from ONE fertilized egg; also called
monozygotic twins.
• Fraternal twins– Come from TWO different eggs
fertilized by two different sperm; also called dizygotic twins.
WHY STUDY TWINS???
End of Chapter 6