Chapter 3 BIOLOGY AND BEHAVIOR HOLT Psychology 4/19/2017 Chapter 3 BIOLOGY AND BEHAVIOR Section 1: The Nervous System Section 2: The Brain: Our Control Center Section 3: The Endocrine System Section 4: Heredity: Our Genetic Background Chapter 3

Chapter 3:Section 1 The Nervous System Chapter 3

Main Objective: Explain how messages are transmitted by neurons and describe the functions of the peripheral nervous system. Chapter 3

What does the Nervous System do??? Thinking Feeling Moving Dreaming Regulates internal functions Learning/memory Etc…. Chapter 3

Consists of 2 main parts: Central Nervous System: Brain and spinal cord 2. Peripheral Nervous System: * made up of nerve cells that send messages between the central nervous system and all the parts of the body. Chapter 3

Neurons: Neurons: A nerve cell; the basic building block of the nervous system. Each of us has more than 100 billion neurons!!! Chapter 3

Components of a Neuron: Cell Body: Produces energy that fuels the activity of the cell. Dendrites: Receive information from other neurons and pass the message through the cell body Axon: Carries messages away. Chapter 3

Components of Neuron (cont’d) Myelin sheath: A white, fatty substance that insulates axons and enables rapid transmission of neural impulses. Axon terminals: Small fibers branching out from an axon. Chapter 3

The Communication Process: Messages are sent from the axon terminals of one neuron to the dendrites of other neurons. In order for a message to be sent from one neuron to another neuron, it must cross the synapse A junction between the axon terminals of one neuron and the dendrites of another neuron. Less than a millionth of an inch wide! Chapter 3

Anatomy of 2 Neurons: Chapter 3

Communication (cont’d) Messages are received by the dendrites and travel through the cell body and the axon to the axon terminals. They cross synapses to the dendrites of other neurons New synapses can develop between neurons that were not previously connected, as when we learn something new!! Chapter 3

Neurotransmitters: Chemical Messengers Neurons send messages across synapses through the release of neurotransmitters. Chemicals that are stored in sacs in the axon terminals. 100’s can be fired every second!! Chapter 3

Neurotransmitters (cont’d) The message is converted into an electrical impulse that travels the length of the neuron. The message is then transmitted to the next neuron by neurotransmitters This whole process takes only a fraction of a second!!! Chapter 3

Different Types of Neurotransmitters! Acetylcholine (Ach): control of muscles. Plays a part in Alzheimer’s disease Dopamine: motor behavior Deficiency plays a role in Parkinson's disease Serotonin: emotional arousal and sleep Chapter 3

OVERVIEW OF MESSAGE TRANSMISSION VIA NEURONS Section 1: The Nervous System Messages are sent from the axon terminals of one neuron to the dendrites of other neurons Messages travel in one direction and are received by the dendrites and travel through the cell body and the axon to the axon terminals. From there messages cross synapses to the dendrites of other neurons. Chapter 3

Hmmm…What do you think??? Endorphins are neurotransmitters that NATURALLY reduce pain and boost mood. Flooding the brain with painkillers, antidepressants, or other drugs may cause the brain to stop producing endorphins. Thus, when such a drug is discontinued, a person may experience a period of discomfort—ranging from mild to agonizing– until the brain resumes production of endorphins. What do you think about antidepressants? Do the benefits outweigh the potential harm? Chapter 3

The Central Nervous System: Consists of brain and spinal cord Chapter 3

Central Nervous System (cont’d) Spinal cord: A column of nerves within the spine that transmit messages to and from the brain. Protected by the spine. Spinal reflex: simple, automatic response to something. EX: Remove hand for hot stove! Chapter 3

Other simple Reflexes: Blink when dust in your eye Sneeze with pepper Tapping on knee to see if kick Knee-jerk reflex Want to try?…sit on desk with legs crossed. The “doctor” needs to gently strike the knee with a “karate chop”. Does the knee jerk? Chapter 3

THE PERIPHERAL NERVOUS SYSTEM Section 1: The Nervous System Responsible for transmitting messages between the central nervous system and all part of the body and is made up of the somatic and autonomic nervous system Chapter 3

The somatic nervous system transmits sensory messages to the central nervous system. Activated by touch, pain, changes in temperature, and changes in body position. Enables us to experience: Hot/cold; pain/pressure; helps us maintain posture/balance. Chapter 3

2 divisions: Sympathetic Parasympathetic The autonomic nervous system regulates the body’s vital functions such as heartbeat and breathing. 2 divisions: Sympathetic Parasympathetic Chapter 3

Sympathetic System: Activated when a person is going into action, perhaps because of some stressful event. “Fight-or-Flight” Prepares you to confront situation or to run away! May suppress digestion, increase heart & respiration rates, and elevate blood pressure. Chapter 3

Parasympathetic Nervous System: Restores body’s reserves of energy after an action has occurred. EX: Heart rate and blood pressure are normalized, breathing is slowed, and digestion returns to normal. Chapter 3

The Brain: Our Control Center Chapter 3: Section 2 The Brain: Our Control Center Chapter 3

Main Objective: Identify the major structures of the brain, and explain the functions of each structure. Chapter 3

Brain Divided into 3 Sections: Hindbrain Midbrain Forebrain Chapter 3

Hindbrain: Medulla: Pons: Cerebellum: Vital functions such as heart rate, blood pressure, and breathing. Pons: Located in front of medulla and is involved in regulating body movement, attention, sleep, and alertness. Cerebellum: Balance and coordination. Chapter 3

The Midbrain: Located between hindbrain and forebrain. Vision and hearing Contains part of reticular activating system: Part of brain that is involved in attention, sleep, and arousal. EX: Drugs/alcohol can affect this alertness. Chapter 3

Involved in complex thinking processes!! The Forebrain: Involved in complex thinking processes!! 4 key areas: Thalamus Hypothalamus Limbic System Cerebrum Chapter 3

Thalamus: The structure of the brain that relays messages from the sense organs to the cerebral cortex. EX: Relays message to brain, such as pain, in order for brain to respond. Chapter 3

Hypothalamus: The neural structure located below the thalamus that controls temperature, hunger, thirst, and various aspects of emotion: Sexual behavior; caring for offspring, aggression; etc…. Chapter 3

Limbic System: A group of neural structures at the base of the cerebral hemispheres that is associated with emotion, motivation, hunger, sex, and aggression. Chapter 3

Cerebrum: The large mass of the forebrain, consisting of two hemispheres. Cerebral Cortex: The bumpy, convoluted surface of the brain; the body’s control and information-processing center. Chapter 3

The Cerebral Cortex: What Makes Us Unique Made up of right and left hemispheres. Corpus callosum: The nerve fibers that connect the left and right hemispheres of the cerebral cortex. Chapter 3

Information received by one side of the body is transmitted to the OPPOSITE hemisphere of the brain. Each hemisphere of the brain is divided into four parts/lobes. Chapter 3

Complete the following on the SAME handout! Occipital Lobe: Vision Chapter 3

Temporal Lobe: Hearing/Auditory Chapter 3

Parietal Lobe: Sensory Cortex: Warmth, cold ,touch ,and pain Chapter 3

Frontal Lobe: Motor cortex Neurons in the motor cortex fire when we move certain parts of our body. Chapter 3

Association Areas: Association areas: Areas of the cerebral cortex that are involved in such mental operations as thinking, memory, learning, and problem solving. Shape information into something meaningful. EX: Puzzle Chapter 3

Language functions based in left hemisphere Language Abilities: Right-handed people: Language functions based in left hemisphere About 2 out of 3 left-handed people: Language in left hemisphere Chapter 3

2 Key Language Areas: Broca’s Area: Wernicke’s Area: Located in frontal lobe. Controls area of face used for speaking. If damaged, then person speaks slowly, using simple sentences! Wernicke’s Area: Located in temporal lobe Pieces together sounds and sights If damaged, then speech becomes meaningless!! EX: “Stealing cookies”…pg. 63 Chapter 3

Left vs. Right Hemispheres: Left Hemisphere: Language, logic, problem solving, mathematical computation. Right Hemisphere: Imagination, art, feelings, and spatial relations. Even though have heard “right brained” and “left brained” the hemispheres DO NOT act independently of each other!! Chapter 3

Midsaggital Plane: Chapter 3

Is Phineas Gage Still the Same Man??? Turn to Pg. 65 Is Phineas Gage Still the Same Man??? Chapter 3

Methods of Studying the Brain: Accidents: Accidents and brain damage Electrical Stimulation of the Brain: Stimulate parts of brain to change behavioral patterns. Chapter 3

The Electroencephalogram (EEG): Electrodes record electrical activity of brain. Used to diagnose some psychological disorders and locate tumors. Chapter 3

Scans: CAT scan : Computerized axial tomography 3-dimensionanl view of brain. MRI: Magnetic resonance imaging More powerful; shows details more clearly PET scan: Positron emission tomography Show activity of brain at given time Chapter 3

Chapter 3: Section 3 The Endocrine System Chapter 3

Main Objective: Explain how hormones secreted by the major glands of the endocrine system affect the body. Chapter 3

Endocrine System: Consists of glands that secrete substances, called hormones, into the bloodstream. Chemicals produced by the endocrine glands that regulate specific body functions. Glands include: Pituitary gland Thyroid gland Adrenal glands Testes Ovaries Chapter 3

Pituitary Gland: About the size of a pea. “Master gland”…VERY IMPORTANT Stimulated by hypothalamus: Responsible for the secretion of many different hormones that affect various aspects of behavior. EX: Growth hormones; Prolactin (stimulates milk on nursing women) Chapter 3

The Thyroid Gland: Produces Thyroxin: Affects body’s metabolism…its rate of converting food to energy. Hypothyroidism: Too little thyroxin Can lead to overweight. Cretinism: Too little thyroxin in children. Stunted growth/ mental retardation Chapter 3

The Adrenal Glands: Located above the kidneys Outer layer (cortex): Secrete cortical steroids, which increase resistance to stress & promote muscle development. Also, cause liver to release stored sugar, making energy available for emergencies. Chapter 3

Adrenal Glands (cont’d) Also produce adrenaline and noradrenalin: Released when sympathetic nervous system activated. Help arouse body, enabling person to cope with stressful situation. Chapter 3

The Testes and the Ovaries: (continued) The Testes and the Ovaries: Section 3: The Endocrine System Testes and Ovaries – produce the hormones testosterone, estrogen, and progesterone that play an important role in development, development of primary and secondary sex characteristics and have psychological as well as biological effects. Chapter 3

Testosterone: Male sex hormone. Produced by testes in males. Small amount in females produced by ovaries. Produced by testes in males. Stimulates growth of male sex organs. Chapter 3

Estrogen and Progesterone: Female sex hormones produced by ovaries. Low levels found in men. Responsible for the following: Breast enlargement; regulates menstrual cycle; PMS; higher levels of estrogen connected with feelings. Chapter 3

Our Genetic Background Chapter 3: Section 4 Heredity: Our Genetic Background Chapter 3

Main Objective: Explain the role of chromosomes and genes in heredity and evaluate the methods used by psychologists to study the role of heredity in determining traits. Chapter 3

What is Heredity?? Heredity: The transmission of characteristics from parents to offspring. Contribute to the following: Appearance, personality, psychological disorders Chapter 3

Genes and Chromosomes: The basic building blocks of heredity. Traits determined by pairs of genes…one gene in each pair from each parent. Chromosomes: Threadlike structures in which genes are found, which are composed of DNA (deoxyribonucleic acid) Double helix 46 chromosomes with 23 pairs In pairs…one from mom and one from dad. Chapter 3

Oh!!! It’s A ????? 23rd pair: Female: Male: Determines sex 2 X-chromosomes Male: 1 X & 1 Y chromosome Father determines sex of baby! Chapter 3

Nature vs. Nurture: Nature: Nurture: What people inherit. Environmental factors Family, education, culture, everyday living experiences Chapter 3

What do most psychologists believe?? Believe nature & nurture are equally important! Chapter 3

Kinship Studies: Kinship: 2 Common types: Twin Studies Adoptee Studies Refers to the degree to which people are related, based on genes. 2 Common types: Twin Studies Adoptee Studies Chapter 3

Twin Studies: Identical twins: Fraternal twins: Differences due to environment (nurture) More likely to share personality traits & psychological disorders (Ex: autism) Fraternal twins: Differences due to genes AND environment Share 50% of genes Chapter 3

Adoptee Studies: If children act more like biological families –then behavior may be largely influenced by heredity!! Provides ways of sorting out the effects of nature and nurture Chapter 3

Twins Reared Apart: Psychological and personality traits are influenced by heredity. A way of finding out that twins reared apart share many of the same mannerisms despite their separation EX: Intelligence, aggression, leadership. http://www.youtube.com/watch?v=Vlr4mwtjEKY Chapter 3

Does Heredity Determine Our Personalities?? Turn to Pg. 73 Chapter 3

End of Chapter 3