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Today’s Agenda:. Journal Questions: a. What is the function of the frontal lobe of your brain? b. What is the function of your sympathetic nervous system? *1. Lecture II: Neuron & Neurotransmitters 2. Homework: Read Chapter 50. The Amazing Brain. Dr. Rick Woodward
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Today’s Agenda: Journal Questions: a. What is the function of the frontal lobe of your brain? b. What is the function of your sympathetic nervous system? *1. Lecture II: Neuron & Neurotransmitters 2. Homework: Read Chapter 50 Dr. Rick Woodward
The Amazing Brain Dr. Rick Woodward “Your conscious life is an awake dream.” Dr. Rick Woodward
Organization of the Nervous System I. Central Nervous System consists of: 1. Brain 2. Spinal Cord II. Peripheral Nervous System consists of: 1. Somatic Nervous System (1) Cranial Nerves: 12 pairs (2) Spinal Nerves: 31 pairs 2. Autonomic Nervous System (1) Sympathetic Nervous System (2) Parasympathetic Nervous System Dr. Rick Woodward
Central Nervous System A. Composed of: 1. The Brain (called the Cerebrum) 2. The Spinal Cord Dr. Rick Woodward
Your Brain A. The brain has roughly 100 billion cells. B. 10% of these cells are electrical conducting cells called neurons. C. The brain’s left hemisphere controls language in most people, typically contains about 186 million more neurons than the right (Science Illustrated March/April 2011) Dr. Rick Woodward
The Neuron: One neuron dies every second starting at birth, which means we lose 31 million neurons every year. Dr. Rick Woodward
Your Brain D. The average brain weighs about 3 pounds. (1) Male brains typically weigh 10% more than female brains. Dr. Rick Woodward
Your Brain E. People who drink alcohol heavily, have, on average, 1.6% less brain volume than those who don’t drink alcohol. Dr. Rick Woodward
Your Brain F. What is the brain made of? (1) 77 – 78% Water (2) 10 - 12% Fat (3) 2% Other Organic Compounds (4) 1% Carbohydrates (5) 1% Inorganic Salts Dr. Rick Woodward
Your Brain G. 8 to 10 Seconds is the time it takes to lose consciousness when the brain is deprived of blood. (1) After 40 to 120 seconds, brain damage becomes more likely. Dr. Rick Woodward
Your Brain H. Brain Imaging: Advances in Neuroscience (The area of the brain’s surface if it were unfolded would be 22 square feet or 34 pages of your textbook laid end-to-end.) Dr. Rick Woodward
Overview of the Parasympathetic & Sympathetic Nervous Systems Dr. Rick Woodward
The Process of Memory -Receiving Information: A. Short Term Memory 1. Immediate Memory 2. Working Memory -Encoding: Transforming Short Term Memory into Long Term Memory Dr. Rick Woodward
Types of Memory Immediate Memory: Lasts only 1 to 2 seconds. a. Sensory Memory: Briefly holds stimuli from the environment. (in about .5 to 1 second for vision and 3 to 4 seconds for hearing.) Dr. Rick Woodward
Types of Memory Short-Term Memory: Loss of information occurs within 1 minute unless the material is continually rehearsed. a. An fMRI image of the areas used for executive functions such as short-term memory tasks. Dr. Rick Woodward
Types of Memory b. Working Memory: Deliberate thinking takes place. -Limited Capacity (about 7 items) -Limited Duration (about 20 seconds) Dr. Rick Woodward
Working Memory as a Filter or Screen: Working Memory has three choices: (1) Disregard the information (purge it from memory)
Working Memory as a Filter or Screen: 2) Retain the information by repeating it over and over (rehearsal). (3) Transfer the information into long-term memory though rehearsal or by connecting it with information already there (encoding). Dr. Rick Woodward
Long-term Memory is our Permanent Information Store (Reference library) It is the conversion of short-term memory into long-term storage –this process is called consolidation (1) Declarative Knowledge: Knowledge of facts, definitions, and rules. (2) Procedural Knowledge: Knowledge of how to perform activities. Dr. Rick Woodward
Special Areas of the Brain Dr. Rick Woodward
Special Areas of the Brain A. Hippocampus: Learning & Memory (processing from short-term to long-term memory) -Researchers have discovered that Alzheimer’s Disease begins here; initial site of specific protein production that eventually forms amyloid plaques. B. Hypothalamus: Various day-to-day body functions (homeostasis), including appetite, emotional expression of pleasure, rage, fear. Dr. Rick Woodward
The Amygdala C. Amygdala (The Primitive Brain): Plays a vital role in social behavior (impulse control); interpreting facial expressions. Memory of fear involves the amygdala. (Recall: Teenagers tend to use their amygdala rather than their frontal lobe)
Special Areas of the Brain d. Thalamus: Regulates the flow of sensory information. Dr. Rick Woodward
The Neuron is the functional unit of the brain. • The human brain consists of a trillion (1,000,000,000,000) neurons. Dr. Rick Woodward
Parts of the Neuron: a. Axon: Sends out information (conducts impulses) b. Dendrite: Receives information c. Cell Body: Contains the nucleus d. Myelin: Insulates axons so that transmission of impulses is rapid. Dr. Rick Woodward
What’s the matter? • There are two types of matter: 1. Gray Matter (Composed of Neurons & Cell Bodies) a. Place where computation takes place and memories are stored. 2. White Matter (Axons) a. Determines the speed at which information can be processed. 3. The density of gray and white matter in the brain are determined by genes and environmental factors, such as experience. Dr. Rick Woodward
What’s the matter? A. There are two types of matter: (1) White Matter (millions of communication cables, each one containing a long, individual wire, or axon, coated with a white, fatty substance called myelin.) a. Like the trunk lines that connect telephones in different parts of a country, this white cabling connects neurons in one region of the brain with those in different regions. Dr. Rick Woodward
What’s the matter? Recent Research “White Matter Matters.” –Scientific America (March 2008) 2. “For decades neuroscientists exhibited little interest in white matter. They considered the myelin to be mere insulation and the cables as passive passageways.” -Most research has been on the synapse. Dr. Rick Woodward
What’s the matter? Nerve Transmission: Healthy Myelinated Nerve versus Damaged Nerved Dr. Rick Woodward
What’s the matter? 3. New studies show changes in myelin as one learns and practices. a. Myelin is produced until age 25. -The brain does not finish wrapping human axons until early adulthood. “Critical Windows for Learning.” Dr. Rick Woodward
What’s the matter? 4. The importance of myelin: a. “Modern investigation has revealed that nerve impulses race down axons on the order of 100 times faster whey they are coated with myelin.” Dr. Rick Woodward
What’s the matter? 5. “Myelin responds to the environment and participates in learning, in part by strengthening neuronal connects.” Dr. Rick Woodward
What’s the matter? 6. “White matter abnormalities have been found in people affect by ADHD, Bipolar Disorder, Language Disorders, Autism, cognitive decline in aging and Alzheimer’s disease and even in individuals afflicted with pathological lying.” Dr. Rick Woodward
The Synapse: The point where information is transmitted from one neuron to the next. (Synapse = Gap) A. The number of possible different combinations of synaptic connections among the neurons in a single human brain is larger than the total number of atomic particles that make up the known universe. (Don’t you feel smart!!!) Dr. Rick Woodward
Active Learning A. Learning is about creating and strengthening the neural pathways in the brain. B. Electrical signals most jump across the synapse (gap) in order for us to lean anything new. Dr. Rick Woodward
Active Learning C. The first time that we learn something, demands the most effort to cross the gap (synapse). (1) Analogy: Crossing a deep ravine. Dr. Rick Woodward
Active Learning 2. The first time you attempt to cross a deep ravine may be quite challenging. Dr. Rick Woodward
Active Learning 3. After you cross the ravine once, it becomes easier and easier. -journeys across get easier and easier as with learning. Dr. Rick Woodward
Active Learning 4. As the signal crosses the gap again and again, we get a more solid pathway. (i.e. building a bridge across the gap) Dr. Rick Woodward
Active Learning 5. After you build a bridge, learning becomes almost effortless. a. To learn better, we need to make it easier to cross the synaptic ravine by building and strengthening our bridges. Dr. Rick Woodward
Neurotransmitters Dr. Rick Woodward
Neurotransmitters Chemicals that transmit information. A. Serotonin: Active in maintaining waking EEG patterns. Decreased; related to depression Increased; related to obsessive-compulsive disorder. O.C.D. = Excessive concern with order, rules, and trivial details. Dr. Rick Woodward
EEG Brain Waves Dr. Rick Woodward
Neurotransmitters B. Dopamine: Active in maintaining normal motor behavior. -Decreased; muscles are rigid and movements are difficult. i.e. Parkinson’s Disease (T.R.A.P.) -Increased; May be related to schizophrenia (delusions, hallucinations, disorganized speech) Dr. Rick Woodward
Current Research a. The brain changes physiologically “plasticity” as a result of experience . b. IQ is not fixed at birth. –Higher development of white matter is correlated directly with higher IQ. c. Children who suffer severe neglect have up to 175 less white matter in the corpus callosum (structure that connects the two hemispheres of the brain). d. Some abilities are acquired more easily during certain sensitive periods, or “critical windows of opportunity.” e. Learning is strongly influenced by emotion. Dr. Rick Woodward
Effects of Drugs on the Nervous System Dr. Rick Woodward
Developmental Disorders of the Nervous System a. Major deformities of the nervous system occur before week 20 of pregnancy. b. Anencephaly (no brain) can occur during weeks 3-4. Dr. Rick Woodward
Advances in Technology I. Visualizing Brain Activity a. Colored magnetic resonance imaging (MRI) scan of the axial section of the human brain showing a metastatic tumor (yellow). Dr. Rick Woodward
Advances in Technology II. Visualizing Brain Activity b. Positron Emission Tomography Dr. Rick Woodward
Advances in Technology III. Visualizing Brain Activity c. DTI (Diffusion Tensor Imaging) -Shows white matter in action. Dr. Rick Woodward