CHAPTER 3 Biology and Behavior Question: What major areas do biological psychologists study?

Nervous System Environment CHAPTER 3 Biology and Behavior Major Areas of Study for Biological Psychologists Heredity Endocrine System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 3 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

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 4 Chapter 3 Essential Questions: How are messages transmitted by neurons, and what are the functions of the peripheral nervous system? Section 1: The Nervous System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 5 Chapter 3 What does the nervous system do? Involved in thinking, dreaming, feeling, and moving. Regulates internal functions. Affects how we react to the external world. When we learn a new behavior or acquire new information, the nervous system registers the experience and changes to accommodate it. Section 1: The Nervous System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 6 Chapter 3 There are two main parts to the nervous system… Central nervous system. Brain and spinal cord. Peripheral nervous system. Nerve cells that send messages between the CNS and the rest of the body. Section 1: The Nervous System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 7 Chapter 3 Neurons (nerve cells) 100 billion. Send and receive messages. Neurons are involved in everything… Sensation of a pinprick, first steps, writing a poem, past memory… Section 1: The Nervous System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 8 Chapter 3 What are the components of a neuron? 1. Cell body – produces energy. 2. Dendrites – receive information. 3. Axon – send information. Neurons have many dendrites, but only one axon, ranging in length from fractions of an inch to several feet. Section 1: The Nervous System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 9 Chapter 3 The Axon Covered in a myelin sheath, a white fatty substance that insulates and protects it. Axon terminals branch out from the end of the axon to the synapse – a junction between the axon terminals of one neuron and the dendrites of another neuron. Section 1: The Nervous System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 10 Chapter 3 How are messages transmitted from one neuron to another? 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 Section 1: The Nervous System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 11 Chapter 3 Section 1: The Nervous System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 12 Chapter 3 Neurotransmitters – Chemical Messengers Messages are sent across synapses via neurotransmitters – chemicals stored in sacs in the axon terminals. Section 1: The Nervous System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 13 Chapter 3 Neurotransmitters – Chemical Messengers Dozens of types… Acetylcholine – control of muscles. Too little impairs memories. Dopamine – motor behavior. Too little causes Parkinson’s. Too little contributes to Schizophrenia. Noradrenaline – prepares the body for action. Serotonin – emotional arousal and sleep. Section 1: The Nervous System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 14 Chapter 3 The Central Nervous System Brain and spinal cord – transmit messages and control reflexes. Section 1: The Nervous System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 15 Chapter 3 The Peripheral Nervous System Transmits messages between the CNS and the rest of the body. Somatic Nervous System Transmits sensory messages – touch, pain, changes in temperature, body position, etc. Automatic Nervous System (2 divisions) Regulates involuntary body functions – vital functions, heartbeat, breathing, digestions, blood pressure, etc. Section 1: The Nervous System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 16 Chapter 3 The Autonomic Nervous System Two main divisions… 1. Sympathetic – activated when a person is going into action (fight or flight). Suppresses digestion, increases heart and respiration rates, elevates blood pressure. 2. Parasympathetic – restores normal functions after an action has occurred. Section 1: The Nervous System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 17 Chapter 3 Review Question: How are messages transmitted by neurons, and what are the functions of the peripheral nervous system? MESSAGE TRANSMISSION VIA NEURONS 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 Section 1: The Nervous System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 18 Chapter 3 Review Question: How are messages transmitted by neurons, and what are the functions of the peripheral nervous system? FUNCTIONS OF THE PERIPHERAL 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 The somatic nervous system transmits sensory messages to the central nervous system The autonomic nervous system regulates the body’s vital functions such as heartbeat and breathing Section 1: The Nervous System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 19 Chapter 3 Section 2: The Brain: Our Control Center Essential Question: What are the major structures of the brain, and what is the function of each structure?

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 20 Chapter 3 Section 2: The Brain: Our Control Center What’s really happening up there? Thought! Ancient civilizations believed that we were exactly like animals, except our ability to feel, think creatively, analyze things, etc. could not be explain biologically. The body was inhabited by souls or demons. Our language still reflects this… “deep in one’s heart,” “to know something by heart,” “to have a change of heart.” We now know that this is happening in the brain – biological processes and psychological phenomena are linked.

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 21 Chapter 3 Section 2: The Brain: Our Control Center 3 Parts of the Brain 1. Hindbrain – vital functions. 2. Midbrain – vision and hearing. 3. Forebrain – complex functions like thought and emotion.

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 22 Chapter 3 Section 2: The Brain: Our Control Center The Hindbrain – vital functions. Medulla – vital functions such as heart rate, blood pressure, and breathing. Pons – regulates body movement, attention, sleep, and alertness. Cerebellum – balance and coordination.

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 23 Chapter 3 Section 2: The Brain: Our Control Center The Midbrain – vision and hearing. Reticular Activating System Runs from the hindbrain, through the midbrain, into the forebrain. Important for attention, sleep, and emotional arousal. Increases heart rate, blood pressure, and brain activity. Some drugs, like alcohol, reduce the activity of this system.

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 24 Chapter 3 Section 2: The Brain: Our Control Center The Forebrain – complex functions. Thalamus – transmits/relays sensory information. Hypothalamus – regulates body temperature, stores nutrients, controls emotions and behavior, hunger, thirst, sex drive, caring for offspring, aggression, etc. Limbic system – learning and memory, hunger, sex drive, aggression. Cerebrum – 70% of the brain. Cerebral cortex covers it. Handles memory, language, emotions, complex motor functions, perception, etc.

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 25 Chapter 3 Section 2: The Brain: Our Control Center The Cerebral Cortex – What Makes Us Unique Two sides, left and right, connected by the corpus callosum. Information received by one side of the body is transmitted to the opposite side of the brain. Separated into four lobes – some are independent, some require interaction for certain actions. Frontal, parietal, temporal, and occipital.

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 26 Chapter 3 Section 2: The Brain: Our Control Center The Cerebral Cortex – What Makes Us Unique

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 27 Chapter 3 Section 2: The Brain: Our Control Center Senses and Motor Behavior Occipital lobe – visual. Temporal lobe – hearing. Parietal lobe – warmth, cold, touch, and pain. Frontal lobe – movement.

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 28 Chapter 3 Section 2: The Brain: Our Control Center Association Areas These are areas that shape information into something meaningful. Ex. – some neurons fire for horizontal lines, others fire for vertical. Frontal lobe – brain’s “executive center,” where problem solving and making decisions occurs as well as retrieving memories. Does not fully develop until around age 25.

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 29 Chapter 3 Section 2: The Brain: Our Control Center Language Abilities Right-handed people – language functions are in the left hemisphere. Left-handed people – 1/3 in the right hemisphere.

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 30 Chapter 3 Section 2: The Brain: Our Control Center Language Abilities Broca’s area – frontal lobe near the motor cortex, damage causes slow, laborious speech, simple sentences. Wernicke’s area – sound and sight, damage causes meaningless, disassociated speech. “Mother is away her working her work to get her better, but when she’s looking the two boys looking the other part. She’s working another time” (Geschwind, 1979). Description of a picture of two boys stealing cookies behind a woman’s back.

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 31 Chapter 3 Section 2: The Brain: Our Control Center Left vs. Right Hemispheres

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 32 Chapter 3 Section 2: The Brain: Our Control Center Methods of Studying the Brain Accidents – measure memory loss and function. Electrical Stimulation – triggers behaviors. Electroencephalogram (EEG) – measures activity in areas. Scans – measures activity in certain areas, similar to EEG.

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 33 Chapter 3 Section 2: The Brain: Our Control Center Essential Question: What are the major structures of the brain, and what is the function of each structure? MAJOR STRUCTURES AND FUNCTIONS OF THE BRAIN Hindbrain – lower part of the brain involved in many vital functions such as heart rate, respiration and balance Midbrain – includes areas that are involved in vision and hearing Forebrain – front area of the brain involved in complex functions such as thought and emotion

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 34 Chapter 3 Question: How do hormones secreted by the major glands of the endocrine system affect the body? Section 3: The Endocrine System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 35 Chapter 3 Endocrine system – glands that secrete hormones into the bloodstream. Hormones – stimulate growth, behavior, emotional reactions, mood, etc. Hormones have specific receptor sites throughout the body and are produced by 4 glands… Section 3: The Endocrine System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 36 Chapter 3 Question: How do hormones secreted by the major glands of the endocrine system affect the body? HORMONES AND EFFECT ON THE BODY 1. Pituitary Gland – responsible for the secretion of many different hormones that affect various aspects of behavior such as the growth hormone “Master gland” – regulates muscle, bone, and gland growth Growth hormone can be stimulated via injection Prolactin – milk production Oxytocin – stimulates labor Linked to maternal care for young in some mammals Section 3: The Endocrine System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 37 Chapter 3 Question: How do hormones secreted by the major glands of the endocrine system affect the body? HORMONES AND EFFECT ON THE BODY 2. Thyroid Gland – produces thyroxin which affects the body’s metabolism Too little – hypothyroidism Overweight Cretisnism – stunted growth and mental retardation Too much – hyperthyroidism Excitability, inability to sleep, and weight loss Section 3: The Endocrine System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 38 Chapter 3 Question: How do hormones secreted by the major glands of the endocrine system affect the body? HORMONES AND EFFECT ON THE BODY 3. Adrenal Gland – the outer layer of the adrenal gland, or cortex, secretes cortical steroids which increase resistance to stress and promote muscle development “At the kidneys” Cause the liver to release stored energy Produces adrenaline and noradrenaline, released by the sympathetic nervous system, to arouse the body to deal with stressful situations Section 3: The Endocrine System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 39 Chapter 3 Question: How do hormones secreted by the major glands of the endocrine system affect the body? 4. 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 Testosterone – male sex hormone Is a steroid, can be injected to enhance muscle mass, stress resistance, energy supply, sex drive, and self esteem Estrogen and progesterone – female sex hormones Regulate cycles, PMS, optimal cognitive functioning, sex drive, feelings of well- being Section 3: The Endocrine System HORMONES AND EFFECT ON THE BODY (continued)

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 40 Chapter 3 Question: How do hormones secreted by the major glands of the endocrine system affect the body? HORMONES AND EFFECT ON THE BODY Pituitary Gland – responsible for the secretion of many different hormones that affect various aspects of behavior such as the growth hormone Thyroid Gland – produces thyroxin which affects the body’s metabolism Adrenal Gland – the outer layer of the adrenal gland, or cortex, secretes cortical steroids which increase resistance to stress and promote muscle development Section 3: The Endocrine System

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 41 Chapter 3 Question: How do hormones secreted by the major glands of the endocrine system affect the body? 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 Section 3: The Endocrine System HORMONES AND EFFECT ON THE BODY (continued)

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 42 Chapter 3 Question: What is the role of chromosomes and genes in heredity, and how do psychologists study the role of heredity in determining traits? Section 4: Heredity: Our Genetic Background

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 43 Chapter 3 Question: What is the role of chromosomes and genes in heredity, and how do psychologists study the role of heredity in determining traits? Heredity – transmission of characteristics from parents to offspring Physical traits – height, hair texture, and eye color Psychological traits – shyness, leadership ability, aggressiveness, and interests in arts and crafts Keep in mind that environment also plays a role Psychological disorders – anxiety and depression, schizophrenia, bipolar disorder, and alcoholism Section 4: Heredity: Our Genetic Background

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 44 Chapter 3 Question: What is the role of chromosomes and genes in heredity? ROLE OF CHROMOSOMES AND GENES IN HEREDITY Genes are the basic building blocks of heredity and traits are determined by pairs of genes Affect everything from blood type to intelligence Most normal human cells contain 46 chromosomes, 23 pairs, which develop particular traits in an individual One from the mother, one from the father The 23rd pair of chromosomes determines the male or female sex Down syndrome – 47 th chromosome Section 4: Heredity: Our Genetic Background

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 45 Chapter 3 Question: What is the role of chromosomes and genes in heredity? NATURE-NURTURE Nature – what people inherit Nurture – what a person is exposed to in life Most psychologists agree that both play a role, the extent of the role is highly controversial. Section 4: Heredity: Our Genetic Background

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 46 Chapter 3 Question: How do psychologists study the role of heredity in determining traits? THE STUDY OF THE ROLE OF HEREDITY Role of heredity in studies through various types of kinship research such as: A.Twin Studies – a useful way to learn about nature and nurture B.Adoptee Studies – provide ways of sorting out the effects of nature and nurture C.Twins Reared Apart – a way of finding out that twins reared apart share many of the same mannerisms despite their separation Section 4: Heredity: Our Genetic Background

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 47 Chapter 3 Question: How do psychologists study the role of heredity in determining traits? THE STUDY OF THE ROLE OF HEREDITY Twin studies Identical twins – share the same genetic makeup, differences must be the result of environment Fraternal twins – share 50 percent of genes, difference could be genetic or environmental Identical twins have high correlations in behaviors/emotions like shyness, irritability, sociability, happiness, as well as psychological disorders such as autism, substance dependence, and schizophrenia Section 4: Heredity: Our Genetic Background

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 48 Chapter 3 Question: How do psychologists study the role of heredity in determining traits? THE STUDY OF THE ROLE OF HEREDITY Twins reared apart Less likely than twins reared together to share common experiences. Thus, similarities are probably due to genetics. Psychological and personality traits such as intelligence, traditionalism, risk avoidance, aggression, and leadership. Mannerism such as how one sits or stands, the number and types of jewelry that is worn. Section 4: Heredity: Our Genetic Background

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 49 Chapter 3 Question: What is the role of chromosomes and genes in heredity, and how do psychologists study the role of heredity in determining traits? ROLE OF CHROMOSOMES AND GENES IN HEREDITY Genes are the basic building blocks of heredity and traits are determined by pairs of genes Most normal human cells contain 46 hormones which develop particular traits in an individual The 23rd pair of chromosomes determines the male or female sex Section 4: Heredity: Our Genetic Background

HOLT, RINEHART AND WINSTON P SYCHOLOGY PRINCIPLES IN PRACTICE 50 Chapter 3 Question: What is the role of chromosomes and genes in heredity, and how do psychologists study the role of heredity in determining traits? THE STUDY OF THE ROLE OF HEREDITY Role of heredity in studies through various types of kinship research such as: A.Twin Studies – a useful way to learn about nature and nurture B.Adoptee Studies – provide ways of sorting out the effects of nature and nurture C.Twins Reared Apart – a way of finding out that twins reared apart share many of the same mannerisms despite their separation Section 4: Heredity: Our Genetic Background