Biology and Behavior

1. Biology and Behavior Mod #3 Neural and Hormonal Systems

2. In 1800, Franz Gall suggested that bumps of the skull represented mental abilities. His theory, though incorrect, nevertheless proposed that different mental abilities were modular. History of Mind Phrenology Bettman/ Corbis

3. Structure of a Neuron

4. Neuron A nerve cell, or a neuron, consists of many different parts.

5. Neurons: The cells of the nervous system Communicative cells: 1. Sensory Neurons: receive signals from outside nervous system 2. Motor Neurons: transmit signals to muscles 3. Interneurons: communicate with each other

6. The Nervous System: Two Systems • The Peripheral Nervous System • Somatic – voluntary control of muscles • Autonomic – involuntary control of glands and muscles of our internal organs (heartbeat, digestion, etc.) • The Central Nervous System – the brain and the spinal cord • Thinking, feeling, and acting • Neural networks of billions of neurons • Makes us unique human beings

7. A single nerve cell has a central cell body, branching threads called dentrites, and a long wirelike axon. The dendrites carry the signal toward the cell body, while the axon carries it away. Neurons Axon Dendrite Cell Body

8. A bundle of neurons is a nerve. Nerves are the body’s wiring. Nerves branch out from the brain and spinal cord to eyes, ears, stomach, skin, bones, and teeth. The tickest nerves look like pieces of white rope.

9. Neuron Communication Click below to see how a neuron works: • http://www.youtube.com/watch?v=xRkPNwqm0mM&NR=1 • http://www.youtube.com/watch?v=WyQbME6ilV4 • http://www.youtube.com/watch?v=FR4S1BqdFG4&feature=related

10. Neural CommunicationNot available to Online Students

11. How Neurons Communicate • Axon terminals release neurotransmitter • Neurotransmitter enters synaptic gap • Neurotransmitter binds to receptors that it fits • Reuptake: surplus reabsorbed

12. Action Potential A neural impulse. A brief electrical charge that travels down an axon and is generated by the movement of positively charged atoms in and out of channels in the axon’s membrane.

13. Sights and Sounds of a Neuron • http://faculty.washington.edu/chudler/flash/son1.html This is how the electrical activity in an activated neuron looks and sounds!

14. Threshold Threshold:Each neuron receives excitatory and inhibitory signals from many neurons. When the excitatory signals minus the inhibitory signals exceed a minimum intensity (threshold) the neuron fires an action potential. I can’t take it any- more. I’ve reached my threshold!!!

15. The Spinal Cord 31 pair of spinal nerves 33 vertebre bones thousands of neurons - sensory and motor

16. Neurotransmitters • More than 40 known types • Each neurotransmitter has a unique effect. • Neurotransmitters are affected (changed) by: • Neural diseases • Drugs

17. Neurotransmitters: What they do • Acetylcholine:learning, memory, muscle movement Not enough = Alzheimer’s • Serotonin:mood and food intake, arousal Not enough = depression • Dopamine:movement and to frontal lobe activity – Too much (excess receptor activity) =Schizophrenia; Not enough = Parkinson’s disease • Norepinephrine:alertness & wakefulness – Not enough = depression

18. Neurotransmitters: What they do • Endorphins: regulate firing of pain neurons • GABA: inhibits neurotransmission Not enough = seizures, tremors, insomnia • Glutamate: excitatory, helps memory – ly Too much over-stimulates brain = seizures, migraines (why some people avoid MSG)

19. Runners HighNot available to Online Students

20. The Psycho Pharmacologist? Just for fun! UTube http://www.youtube.com/watch?v=ElFL4CrDMIY Marijuana and schizophrenia - article http://www.schizophrenia.com/prevention/streetdrugs.html

21. Drugs • Many drugs influence synaptic transmission • Drugs can be: • agonistic (excite) • antagonistic (inhibit)

22. Agonistic (excite) Drugs • Increase release of neurotransmitter, or • Activate receptors, imitate neurotransmitter, or • Inhibit reuptake of neurotransmitter

23. Examples of Agonistic: Exciting or Stimulating Drugs • Caffeine (glutamate) • Amphetamines, cocaine, Ritalin (dopamine) • Valium, alcohol (GABA) • Prozac (serotonin) • Morphine, heroin (endorphins)

24. Antagonistic (inhibiting) Drugs • Interfere with release of neurotransmitter or • Occupy and block neurotransmitter sites Antagonistic drugs

25. Examples of antagonistic(inhibiting) drugs • Curare (acetylcholine) • Botulism toxin (acetylcholine)

26. The Nervous System

27. Sites for Neurons How Neurons Work: http://bcs.worthpublishers.com/myers6e/pages/bcs-main.asp?v=category&s=00080&n=02010&i=02080.01&o=|02010|&ns=23 How Neurons Are Affected by: 1. Cocaine: http://www.pbs.org/wnet/closetohome/animation/coca-anim-main.html 2. Antidepressants: http://www.zoloft.com/index.asp?pageid=44 3. Other Drugs: http://www.pbs.org/wnet/closetohome/science/html/animations.html

28. More Sites for Neurons Cocaine http://bcs.worthpublishers.com/myers6e/pages/bcs-main.asp?v=category&s=00080&n=07010&i=07080.01&o=|02010|05010|06010|07010|&ns=119 Prozac http://bcs.worthpublishers.com/myers6e/pages/bcs-main.asp?v=category&s=00080&n=16010&i=16080.01&o=|02010|05010|06010|07010|10010|16010|&ns=215

29. The Nerves Nerves consist of neural “cables” containing many axons. They are part of the peripheral nervous system and connect muscles, glands, and sense organs to the central nervous system.

30. Autonomic Nervous System (ANS) Sympathetic Nervous System: Division of the ANS that arouses the body, mobilizing its energy in stressful situations. Parasympathetic Nervous System: Division of the ANS that calms the body, conserving its energy.

31. Autonomic Nervous System (ANS) Sympathetic NS “Arouses” (fight-or-flight) Parasympathetic NS “Calms” (rest and digest)

32. Central Nervous System The Brain and Neural Networks Interconnected neurons form networks in the brain. Theses networks are complex and modify with growth and experience. Complex Neural Network

33. Central Nervous System The Spinal Cord and Reflexes Simple Reflex

34. The Endocrine System The Endocrine Systemisthe body’s “slow” chemical communication system. Communication is carried out by hormones synthesized by a set of glands.

35. Hormones Hormonesare chemicals synthesized by the endocrine glands that are secreted in the bloodstream. Hormones affect the brain and many other tissues of the body. Epinephrine (adrenaline) increases heart rate, blood pressure, blood sugar, and feelings of excitement during emergency situations.

36. Pituitary Gland Is called the “master gland.” The anterior pituitary lobe releases hormones that regulate other glands. The posterior lobe regulates water and salt balance. You probably want to know about Oxytocin! Recent studies have begun to investigate oxytocin'srole in various behaviors, including orgasm, social recognition, pair bonding, anxiety, trust, love, and maternal behaviors.

37. Thyroid & Parathyroid Glands Regulate metabolic and calcium rate.

38. Adrenal Glands Adrenal glands consist of the adrenal medulla and the cortex. The medulla secretes hormones (epinephrine and norepinephrine) during stressful and emotional situations, while the adrenal cortex regulates salt and carbohydrate metabolism.

39. Gonads Sex glands are located in different places in men and women. They regulate bodily development and maintain reproductive organs in adults.

40. How Does Neurology Relate to Magic? • http://www.scientificamerican.com/video.cfm?lineup=1406165298&id=652064535001 • Watch this film and see how magicians can trick us.

41. Awakening Film http://www.youtube.com/watch?v=FURflBxeTyI Go to the site above to see what happens when the neurons do not communicate effectively. This is the trailer of a film about how one doctor experimented with L-dopa to treat Parkinson’s disease. His new treatment was able to break the blood-brain barrier and awaken people who had literally been asleep for 30 years! You can rent the film to see the whole story.

42. THE END