Chapter 6 Biopsychology

Section 1 The Nervous System

The Organization of the Nervous System Peripheral nervous system Central nervous system (CNS) Autonomic nervous system Somatic nervous system Sympathetic nervous system Parasympathetic nervous 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: Forebrain Midbrain Hindbrain

Forebrain A part of the brain that covers the brain’s central core. Includes: Thalamus Hypothalamus Cerebral cortex Cerebrum Limbic system Amygdala Hippocampus

Forebrain Thalamus Hypothalamus Cerebral cortex 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.

Forebrain Cerebrum Limbic system Inner layer of the forebrain. 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.

Hindbrain Located at the rear base of the skull; involved in the basic processes of life. Includes: Cerebellum Medulla Pons

Hindbrain Cerebellum Medulla Pons 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 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. Video Mr. Split-Brainy

How do we study the BRAIN? 1. Recording (EEG) 2. Stimulation 3. Lesions 4. Accidents - Phineas Gage 5. 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.

Phineas Gage

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.

PET Scan

MRI

CAT scan

EEG

Copyright © Allyn & Bacon 2007

Section 3

Copyright © Allyn & Bacon 2007 The Endocrine System (the body’s chemical messenger system) Copyright © Allyn & Bacon 2007

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 Neurotransmitters Endocrine System Glands release hormones into the bloodstream. Nervous System Neurons release neurotransmitters to either excite or inhibit other neurons.

Heredity & Environment Section 4 Heredity & Environment

Heredity The genetic transmission of characteristics from parents to their offspring.

Nature v Nurture Nurture Nature ENVIRONMENT Family, culture, education, and individual differences John Watson Nature The characteristics a person inherits Biological makeup GENETICS Sir Francis Galton

Genes – the basic building blocks of heredity.

Twin Studies Identical twins Fraternal 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