1. Myers’ EXPLORING PSYCHOLOGY (7th Ed) Chapter 2 Neuroscience and Behavior James A. McCubbin, PhD Aneeq Ahmad, Ph.D. (Modified by Ray Hawkins, Ph.D) Worth Publishers

2. Neuroscience and Behavior Neural Communication  Neurons  How Neurons Communicate  How Neurotransmitters Influence Us The Nervous System  The Peripheral Nervous System  The Central Nervous System

3. Neuroscience and Behavior The Endocrine System The Brain  Older Brain Structures  The Cerebral Cortex  Our Divided Brain  Studying Hemispheric Differences in the Intact Brain

4. History of Mind 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. Phrenology Bettman/ Corbis

5. Neural Communication  Biological Psychology  branch of psychology concerned with the links between biology and behavior  some biological psychologists call themselves behavioral neuroscientists, neuropsychologists, behavior geneticists, physiological psychologist, or biopsychologists  Necessity of knowing biological processes underlying human behavior and mental functioning, as much behavior is motivated by biological needs  Neuron  a nerve cell  the basic building block of the nervous system

6. Neural Communication  Dendrite  the bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body  Axon  the extension of a neuron, ending in branching terminal fibers, through which messages are sent to other neurons or to muscles or glands  Myelin [MY-uh-lin] Sheath  a layer of fatty cells segmentally encasing the fibers of many neurons  enables vastly greater transmission speed of neutral impulses

7. Neural Communication

8.  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.  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.

9. Neural Communication  Action Potential Properties  All-or-None Response: A strong stimulus can trigger more neurons to fire, and to fire more often, but it does not affect the action potentials strength or speed.  Intensity of an action potential remains the same throughout the length of the axon.

10. Neural Communication Synapse [SIN-aps] a junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron. This tiny gap is called the synaptic gap or cleft. Neurotransmitters Neurotransmitters (chemicals) released from the sending neuron travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing it to generate an action potential. Reuptake Neurotransmitters in the synapse are reabsorbed into the sending neurons through the process of reuptake. This process applies the brakes on neurotransmitter action.

11. Neural Communication

12. How Neurotransmitters Influence Us Serotonin pathways are involved with mood regulation. From Mapping the Mind, Rita Carter, © 1989 University of California Press

13. Dopamine Pathways Dopamine pathways are involved with diseases such as schizophrenia and Parkinson’s disease. From Mapping the Mind, Rita Carter, © 1989 University of California Press

14. Neural Communication

15. Lock & Key Mechanism Neurotransmitters bind to the receptors of the receiving neuron in a key-lock mechanism.

16. Agonists

17. Antagonists

18. The Nervous System  Nervous System  the body’s speedy, electrochemical communication system  consists of all the nerve cells of the peripheral and central nervous systems  Central Nervous System (CNS)  the brain and spinal cord  Peripheral Nervous System (PNS)  the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body

19. The Nervous System Central (brain and spinal cord) Nervous system Autonomic (controls self-regulated action of internal organs and glands) Skeletal (controls voluntary movements of skeletal muscles) Sympathetic (arousing) Parasympathetic (calming) Peripheral

20. The Nervous System  Nerves  neural “cables” containing many axons  part of the peripheral nervous system  connect the central nervous system with muscles, glands, and sense organs  Sensory Neurons  neurons that carry incoming information from the sense receptors to the central nervous system

21. The Nervous System  Interneurons  CNS neurons that internally communicate and intervene between the sensory inputs and motor outputs  Motor Neurons  carry outgoing information from the CNS to muscles and glands  Somatic Nervous System  the division of the peripheral nervous system that controls the body’s skeletal muscles

22. The Nervous System  Autonomic Nervous System  the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart)  Sympathetic Nervous System  division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations  Parasympathetic Nervous System  division of the autonomic nervous system that calms the body, conserving its energy

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

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

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

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

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

28. 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.

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

30. 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.

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

32. The Brain zHow the brain works (principle of hierarchical inhibitory control) zThree levels of brain hierarchy yHindbrain (central core, comprising cerebellum, pons, and medulla) yOld brain (limbic system) yNew brain (central cortex) zPathways and Feedback

33. The Brain  Brainstem  the oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull  responsible for automatic survival functions  Medulla [muh-DUL-uh]  base of the brainstem  controls heartbeat and breathing

34. The Brain  Reticular Formation  a nerve network in the brainstem that plays an important role in controlling arousal  Thalamus [THAL-uh-muss]  the brain’s sensory switchboard, located on top of the brainstem  it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla

35. The Brain

36.  Cerebellum [sehr- uh-BELL-um]  the “little brain” attached to the rear of the brainstem  it helps coordinate voluntary movement and balance

37. The Brain (How it’s Studied)  Lesion  tissue destruction  a brain lesion is a naturally or experimentally caused destruction of brain tissue  Electrical or Chemical Stimulation

38. Electroencephalogram (EEG)  an amplified recording of the waves of electrical activity that sweep across the brain’s surface  these waves are measured by electrodes placed on the scalp

39. Libet (2004) Experiment

40. Libet (2004): Consciousness and awareness

43. The Brain  Computed Tomography (CT) Scan  a series of x-ray photographs taken from different angles and combined by computer into a composite representation of a slice through the body. Also called CAT scan  Positron Emission Tomography (PET) Scan  a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task  Magnetic Resonance Imaging (MRI)  a technique that uses magnetic fields and radio waves to produce computer-generated images that distinguish among different types of soft tissue; allows us to see structures within the brain

44. PET Scan

45. MRI Scan

46. The Brain  Limbic System  a doughnut-shaped system of neural structures at the border of the brainstem and cerebral hemispheres  associated with emotions such as fear and aggression and drives such as those for food and sex  includes the hippocampus, amygdala, and hypothalamus.  Amygdala [ah-MIG-dah-la]  two almond-shaped neural clusters that are components of the limbic system and are linked to emotion

47. The Brain  Hypothalamus  neural structure lying below (hypo) the thalamus; directs several maintenance activities  eating  drinking  body temperature  helps govern the endocrine system via the pituitary gland  is linked to emotion

48. The Limbic System

49. Rats cross an electrified grid for self-stimulation when electrodes are placed in the reward (hypothalamus) center (top picture). When the limbic system is manipulated, a rat will navigate fields or climb up a tree (bottom picture). Limbic System - Reward Center Sanjiv Talwar, SUNY Downstate

50. The Cerebral Cortex The intricate fabric of interconnected neural cells that covers the cerebral hemispheres. It is the body’s ultimate control and information processing center.

51. Structure of the Cortex Each brain hemisphere is divided into four lobes that are separated by prominent fissures. These lobes are the frontal lobe (forehead), parietal lobe (top to rear head), occipital lobe (back head) and temporal lobe (side of head).

52. Functions of the Cortex The Motor Cortex is the area at the rear of the frontal lobes that control voluntary movements. The Sensory Cortex (parietal cortex) receives information from skin surface and sense organs.

53. Visual Function The functional MRI scan shows the visual cortex is active as the subject looks at faces. Courtesy of V.P. Clark, K. Keill, J. Ma. Maisog, S. Courtney, L.G. Ungerleider, and J.V. Haxby, National Institute of Mental Health

54. Auditory Function The functional MRI scan shows the auditory cortex is active in patients who hallucinate.

55. More intelligent animals have increased “uncommitted” or association areas of the cortex. Association Areas

56. Specialization & Integration Brain activity when hearing, seeing, and speaking words

57. Language Aphasia is an impairment of language, usually caused by left hemisphere damage either to Broca’s area (impaired speaking) or to Wernicke’s area (impaired understanding).

58. Brain Reorganization  Plasticity  the brain’s capacity for modification, as evident in brain reorganization following damage (especially in children) and in experiments on the effects of experience on brain development  Ramachandran & Blakelee (1998) “Phantoms in the Brain” (Myers text, p. 58)

59. Our Divided Brain Our brain is divided into two hemispheres. The left hemisphere processes reading, writing, speaking, mathematics, and comprehension skills. In the 1960s, it was termed as the dominant brain.

60. Splitting the Brain A procedure in which the two hemispheres of the brain are isolated by cutting the connecting fibers (mainly those of the corpus callosum) between them. Corpus Callosum Martin M. Rother Courtesy of Terence Williams, University of Iowa

61. Split Brain Patients With the corpus callosum severed, objects (apple) presented in the right visual field can be named. Objects (pencil) in the left visual field cannot.

62. Divided Consciousness “Look at the dot.” Two words separated by a dot are momentarily projected. “What word did you see?” or “Point with your left hand to the word you saw.” Film

63. Try This! Try drawing one shape with your left hand and one with your right hand, simultaneously. BBC

64. Non-Split Brains People with intact brains also show left-right hemispheric differences in mental abilities. A number of brain scan studies show normal individuals engage their right brain when completing a perceptual task and their left brain when carrying out a linguistic task.

65. Descartes’ “Seat of the Soul” ? zBerson et al. (2005) report that melanopsin, a protein which absorbs light in the eyes (especially blue wave lengths), even in blind persons, stimulates the pineal gland (called the “seat of the soul” by Descartes). The pineal gland in turn produces the hormone melatonin which affects sleep cycles, mood, and sexual activity. Will sitting under a blue light increase happiness? (Source, Spirituality & Health, Sept./Oct. 2005 issue, p. 21)