Myers’ PSYCHOLOGY

1. Chapter 2 – Part INeuroscience, Genetics & Behavior Myers’ PSYCHOLOGY

2. Neural Communication • Biological Psychology • branch of psychology concerned with the links between biology and behavior • Neuron • a nerve cell • the basic building block of the nervous system

3. Neural Communication • Dendrite • 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 tissue that insulates the axons and helps speed their impulses

4. Neural Communication Terminal Buttons(small knobs at the end of axons that secrete chemicals) a.k.a. “Soma”

5. Neural Communication • Action Potential • a neural impulse; the firing of a nerve cell • like a fuse burning from one end to another • chemistry-to-electricity process involves the exchange of electrically charged atoms (ions) • All-or-none response • refractory period

6. Neural Communication • Threshold • the level of stimulation required to trigger a neural impulse • excitatory vs. inhibitory impulses • Increasing the stimulus above the threshold does not increase the action potential’s intensity • What increases the intensity is the number of neurons firing (ie. a slap on the face or a gentle rub)

7. Neural Communication • Synapse • junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron • a.k.a. synaptic gap or cleft • Neurotransmitters • chemical messengers that cross the synaptic gaps between neurons • reuptake - excess neurotransmitters are reabsorbed by the sending neuron

8. Neural Communication • Endorphins • “morphine within” • Neuropeptides (made from amino acids) that occur naturally in the brain • natural, opiate-like neurotransmitters • released in response to pain and vigorous exercise • Neuromodulators • Do not carry neural messages, but can either increase or decrease the activity of specific neurotransmitters

9. Neural Communication

10. Neural Communication • Drug effects on neurotransmission • artificial opiates = “feel-good” chemistry • heroin, morphine • when your body is flooded with these opiate drugs, your brain stops producing its own natural opiates, thus the reason for withdraw during treatment and recovery • various drugs affect communication at the synapse • Agonist – excites; can be a drug molecule that is similar enough to the neurotransmitter to mimic its effects or that blocks a neurotransmitter’s reuptake • Antagonist – inhibits; can be a drug molecule that inhibits a neurotransmitter’s release; could also be enough like the natural neurotransmitter to occupy its receptor site and block its effect but not similar enough to stimulate the receptor

11. Neural Communication

12. Some Neurotransmitters & Their Functions Taken from Essentials Psychology I

13. Some Neurotransmitters & Their Functions Taken from Essentials Psychology I

14. Neural and Hormonal Systems • Nervous System • “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

15. Neural and Hormonal Systems

16. Neural and Hormonal Systems • Nerves • neural “cables” containing many axons • part of the peripheral nervous system • connects the central nervous system with muscles, glands, and sense organs

17. Neural and Hormonal Systems • Sensory Neurons – “afferent” neurons • neurons that carry incoming information from the sense receptors (tissues and sensory organs) to the CNS • Motor Neurons –“efferent” neurons • carry outgoing information from the CNS to muscles and glands (body’s tissues) • Interneurons– “association” neurons • CNS neurons that internally communicate and intervene between the sensory inputs and motor outputs

18. Neural and Hormonal Systems • Autonomic Nervous System • part of the peripheral nervous system • controls the glands and the muscles of the internal organs (such as the heart) • Somatic Nervous System • part of the peripheral nervous system • controls voluntary movements of skeletal muscles

19. Neural and Hormonal Systems • Sympathetic Nervous System • division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situationsAccelerate heartbeat, raise blood pressure, slow digestion, raise blood sugar levels, cool w/ perspiration • Parasympathetic Nervous System • division of the autonomic nervous system that calms the body, conserving its energyDecreases heartbeat, lowers blood pressure, speeds digestion, lowers blood sugar levels, stops perspiration

20. Reflex • a simple, automatic, inborn response to a sensory stimulus a.k.a. “Reflex Arc”

21. Neural and Hormonal Systems • Neural Networks • interconnected neural cells • neurons cluster intogroups throughoutthe body • Cities vs. countryside

22. The Endocrine System • The body’s “slow” chemical communication system; a set of glands that secretes hormones into the bloodstream • Hormones • Chemical messengers produced in one tissue and affect another • Adrenal glands • Secrete hormones epinephrine (adrenaline) or norepinephrine (noradrenaline) which help arouse the body in times of stress (increase heart rate, blood pressure, and blood sugar… told to do so by the autonomic nervous system) • Pituitary gland • Endocrine system’s most influential gland; regulates growth and controls other endocrine glands

23. The Endocrine System

24. The Endocrine System Chart taken from Essentials Psychology I

25. Chapter 2 – Part IINeuroscience, Genetics & Behavior Myers’ PSYCHOLOGY

26. The Brain • Lesion • tissue destruction • a brain lesion is a naturally or experimentally caused destruction of brain tissue

27. 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

28. PET Scan • PET Scan (positron emission tomography) • a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task.

29. The Brain • MRI (magnetic resonance imaging) • 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. Healthy individual on the left; person with schizophrenia on the right

30. The Brain • fMRI (functional MRI) • Can reveal the brain’s functioning, as well as its structure An fMRI scan identified two brain areas that became especially active when a participant lied about holding a 5 of clubs

31. 7 Medical Myths Even Doctors Believe Robert Roy BrittLiveScience Managing EditorLiveScience.comThu Dec 20, 7:20 PM ET Myth #1: We use only 10 percent of our brains. Fact: Physicians and comedians alike love to cite this one. It's sometimes erroneously credited too. But MRI scans, PET scans and other imaging studies show no dormant areas of the brain, and even viewing individual neurons or cells reveals no inactive areas. Metabolic studies of how brain cells process chemicals show no nonfunctioning areas. The myth probably originated with self-improvement hucksters in the early 1900s who wanted to convince people that they had not yet reached their full potential.

32. 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 • base of the brainstem • controls heartbeat and breathing

33. The Brain • Reticular Formation • a nerve network in the brainstem that plays an important role in controlling arousal • filters incoming stimuli and relays important info. to other areas of the brain • Thalamus • 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

34. The Brain • Cerebellum • the “little brain” attached to the rear of the brainstem • it helps coordinate voluntary movement and balance

35. The Limbic System • Limbic System • Emotions: such fear and aggression Drives: such as for food and sex • Includes the hippocampus, amygdala, and hypothalamus. • Hippocampus: memory

36. The Brain • Amygdala[ah-MIG-dah-la] • two almond-shaped neural clusters that are components of the limbic system and are linked to emotions of fear and aggression

37. The Limbic System • 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 • also linked to emotion

38. The Limbic System • Electrode implanted in “reward center”

39. The Cerebral Cortex • Cerebral Cortex • the intricate fabric of interconnected neural cells that covers the cerebral hemispheres • the body’s ultimate control and information processing center • Glial Cells • cells in the nervous system that are not neurons but that support, nourish, and protect neurons Convolutions (gyri) Fissures (sulci)

40. The Cerebral Cortex • Frontal Lobes • involved in speaking and muscle movements and in making plans and judgments • Parietal Lobes • include the sensory cortex • Occipital Lobes • include the visual areas, which receive visual information from the opposite visual field • Temporal Lobes • include the auditory areas

41. The Brain Regions Taken from Essentials Psychology I • Hindbrain • Bottom portion of the brain and an extension of the spinal cord • Major components: medulla, pons, cerebellum, reticular formation (or reticular activating system) • Midbrain • Continues upward from the pons portion of the hindbrain and lies between the hindbrain and forebrain • Forebrain • Makes up the largest part of the brain; most highly developed portion of the brain • Major components: cerebrum (responsible for complex mental activities), limbic system, corpus callosum, thalamus, hypothalamus

42. The Cerebral Cortex

43. The Cerebral Cortex • Motor Cortex • area at the rear of the frontal lobes that controls voluntary movements • Sensory Cortex • area at the front of the parietal lobes that registers and processes body sensations

44. The Cerebral Cortex

45. Association Areas • Areas of the cerebral cortex that are not involved in primary motor or sensory functions • Involved in higher mental functions such as learning, remembering, thinking, and speaking

46. Phineas Gage

47. The Cerebral Cortex • Aphasia • impairment of language, usually caused by left hemisphere damage either to Broca’s area (impairing speaking) or to Wernicke’s area (impairing understanding) • Broca’s Area • an area of the left frontal lobe that directs the muscle movements involved in speech • Wernicke’s Area • an area of the left temporal lobe involved in language comprehension

48. Specialization and Integration

49. Damage to Wernicke’s Area • A patient was asked to describe a picture that showed two boys stealing cookies behind a woman’s back. • The response was, “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.” • Patient was not able to interpret the auditory code sent by the angular gyrus.

50. The Brain’s Plasticity • If an injury or a surgical procedure destroys one part of a child's brain or, as in the case of this 6-year - old, even an entire hemisphere (to eliminate seizures), the brain will compensate by putting other surplus areas to work. One Johns Hopkins medical team, reflecting on the 58 child hemispherectomies they had performed, reports being "awed" by how well children retain their memory, personality, and humor after removal of either brain hemisphere (Vining & others, 1997). • The brain’s ability to modify itself after some type of damage • Some neural tissue can reorganize in response to damage