cog5 lecppt chapter02

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  • 1. 2013 by W. W. Norton & Co., Inc. The Neural Basis for Cognition Chapter 2 Lecture Outline

2. Chapter 2: The Neural Basis for Cognition Lecture Outline Capgras Syndrome: An Initial Example The Principal Structures of the Brain The Visual System 3. Chapter 2: The Neural Basis for Cognition Brain-behavior functions Imaging of brain activity Impairment after damage 4. Capgras Syndrome: An Initial Example Capgras syndrome Recognize loved ones But think they are impostors May think they were kidnapped (or worse!) May even see slight defects 5. Capgras Syndrome: An Initial Example Capgras syndrome results from a conflict: Perceptual recognition is intact. But there is no emotion. Conflict Lack of familiarity 6. Capgras Syndrome: An Initial Example Neuroimaging brain areas involved in Capgrass syndrome 7. Capgras Syndrome: An Initial Example Amygdalar damage results in lack of emotional response 8. Capgras Syndrome: An Initial Example Prefrontal cortex damage impairs reasoning Illogical thoughts are not filtered out 9. Capgras Syndrome: An Initial Example Factual and emotional knowledge are dissociated 9 10. Capgras Syndrome: An Initial Example Cognitive psychology and cognitive neuroscience complement each other Amygdala linked to emotional processing in general 11. The Principal Structures of the Brain One process is broken up by the brain and processed by different areas 12. The Principal Structures of the Brain 12 13. The Principal Structures of the Brain Gages skull A reconstruction of the lesion A portrait of Gage https://www.youtube.com/watch?v=us8nNoGXAc8 14. The Principal Structures of the Brain Loss of a function associated with normal processing 15. The Principal Structures of the Brain Brain 15 Hindbrain Midbrain Forebrain 16. The Principal Structures of the Brain Hindbrain. Atop the spinal cord Basic rhythms Alertness Cerebellum Movements and balance Sensory and cognitive roles 17. The Principal Structures of the Brain The midbrain sits above the hindbrain Coordinates movement, especially eye movement Includes parts of the auditory pathways Regulates the experience of pain 18. The Principal Structures of the Brain The forebrain includes: Cortex, convolutions Subcortical structures 18 19. The Principal Structures of the Brain Axes Division Connection Left-right Longitudinal fissure Corpus callosum Anterior commisure Anterior-posterior Longitudinal fissure N/A Frontal-temporal Lateral Fissure 20. The Principal Structures of the Brain Four cerebral lobes Frontal lobe Parietal lobe Temporal lobe Occipital lobe 21. The Principal Structures of the Brain The subcortical parts of the forebrain include: Thalamus Hypothalamus Limbic System Amygdala Hippocampus 22. Lateralization Brain is roughly symmetrical Commissures connect hemispheres Corpus callosum is the largest 22 23. Lateralization Split brain patients Severing of the corpus callosum Treatment of epilepsy Limits right-left communication https://www.youtube.com/watch?v=Kqy4XVcCf0w 23 24. The Principal Structures of the Brain Cortical organization is contralateral The left side of the body or perceptual world has more representation on the right side of the brain, and vice versa 25. Lateralization 25 Left hemisphere produces language. Right hemisphere can only point. No language. 26. Neuropsychology Neuropsychology Clinical neuropsychology Lesions 26 27. Data from Neuroimaging Computerized axial tomography (CT) X-rays https://www.youtube.com/watch?v=gaiCtdo6CLE Positron emission tomography (PET) Glucose https://www.youtube.com/watch?v=GHLBcCv4rqk CT vs. PET 28. Data from Neuroimaging 28 Visual stimulation result in occipital lobe activity 29. Magnetic resonance imaging (MRI) Data from Neuroimaging https://www.youtube.com/watch?v=1CGzk-nV06g 30. Data from Neuroimaging functional magnetic resonance imaging (fMRI) https://www.youtube.com/watch?v=lLORKtkf2n8 30 31. Data from Neuroimaging Electroencephalogram (EEG) Buildup of chemical neurotransmitter Firing of action potential in a neuron Millions of neurons create an electrical field https://www.youtube.com/watch?v=8Q57q_kQPQY 31 32. Data from Neuroimaging EEG cap with electrodes 32 33. Data from Neuroimaging Every method has its limitations EEG is sensitive to time, not location fMRI detects location but is not time sensitive CT and MRI scans detect brain structures, not activity 33 34. Data from Neuroimaging Combining techniques is more powerful EEG timing fMRI location 34 35. Data from Neuroimaging The fusiform face area (FFA) is active when viewing faces The parahippocampal place area (PPA) is active when viewing houses 36. The Principal Structures of the Brain Increased activity only appears when person is consciously attending to one or the other 37. Data from Neuroimaging Lesions to this area lead to face blindness 37 38. Data from Neuroimaging The identified brain region may not be necessary Activity may be correlated with task. Transcranial magnetic stimulation (TMS) deactivates an area 39. Localization of Function Specific brain areas have specific functions 39 40. The Cerebral Cortex Area Function Primary projection areas Sensory Input Motor Output Rest of cortex Association areas 41. The Cerebral Cortex Primary motor projection areas Greater precision = more brain area Less precision = smaller brain area 42. The Cerebral Cortex Primary projection areas of the cortex 43. The Cerebral Cortex Orderly representation Space proportional to acuity or precision Contralateral representation 44. The Cerebral Cortex Association Areas Create associations between simple ideas and sensations 44 45. The Cerebral Cortex Damage to association cortex results in problems with: Apraxia movement Agnosia identifying objects Aphasia language Neglect syndrome ignoring half the visual world Prefrontal damage planning, strategic thinking, inhibition 46. Brain Cells Detect incoming signals Nucleus and cellular machinery Transmits signals to other neurons 47. Brain Cells Glia Guide development of nervous system Repairs damage Controls nutrient flow Electrical insulation speeds signal transmission 47 48. Presynaptic neuron Postsynaptic neuron Synapse Brain Cells 49. Brain Cells Accumulation of neurotransmitter in postsynaptic cleft Will or will not trigger an action potential = all- or-none effect 49 50. Brain Cells Synaptic transmission One neuron can receive information from many other neurons Can compare many signals and adjust 50 51. The Visual System Knowledge acquired through vision Neural bases of vision well understood 52. The Visual System 53. The Visual System Photoreceptors Rods Cones Lower sensitivity Higher sensitivity Lower acuity Higher acuity Color-blind Color-sensitive Periphery of the retina In the fovea 54. The Visual System 54 Rods are mostly in the periphery; cones mostly in the center 55. The Visual System A series of neurons communicates information from the retina to the cortex In the eye: Photoreceptors Bipolar cells Ganglion cells and the optic nerve In the thalamus: Lateral geniculate nucleus (LGN) In the cortex: V1, the primary visual projection area, or primary visual cortex, located in the occipital lobe 56. The Visual System Cell C is more inhibited than cell B 57. The Visual System What we see is not what we perceive 58. The Visual System Single-cell recording 59. The Visual System Stimulus in center leads to faster firing rates Stimulus in surrounding area leads to slower firing rates 60. The Visual System 61. The Visual System Different neurons in area V1 are specialized, resulting in parallel processing, not serial processing. 62. The Visual System 63. The Visual System Parallel processing in the visual pathway Parvocellular cells Magnocellular cells 64. The Visual System Object shape and identity Object location Parallel processing in the visual system 65. The Visual System The what and where system projected on the brain surface 66. The Visual System The what system: Identification of objects Occipital-temporal pathway Visual agnosia The where system: locations of objects and guiding our responses Occipital-parietal pathway Problems with reaching for seen objects 67. The Visual System Parallel processing splits up problem But we do not see the world as disjointed Binding problem 68. The Visual System Elements that help solve the binding problem Spatial position Neural synchrony 69. The Visual System Attention is also critical for the binding of visual features When attention is overloaded, people will make conjunction errors 70. The Visual System Our account of vision requires both lower- level activities For example, what happens in individual neurons and the synaptic connections between them And higher-level activities For example, the influence of attention on neural activity 71. Chapter 2 Questions 72. 1. A central problem in Capgras syndrome seems to be a difficulty with a) an emotional analysis of faces. b) matching faces that are in view to faces in memory. c) neither a nor b d) both a and b 73. 2. In the drawing at right, parts A, B, C, and D, are a) the frontal lobe, the occipital lobe, the parietal lobe, and the temporal lobe. b) the occipital lobe, the temporal lobe, the parietal lobe, and the frontal lobe. c) the parietal lobe, the frontal lobe, the temporal lobe, and the occipital lobe. d) the temporal lobe, the frontal lobe, the occipital lobe, and the parietal lobe. 74. 3. Many subcortical structures, such as the hippocampus and amygdala, come in groups of two. Why? a) Anatomy involves symmetry. b) There is a hindbrain and midbrain. c) It has to do with lateralization. d) none of the above 75. 4. Which of the following methodologies does not measure brain activity or structure? a) magnetic resonance imaging (MRI) b) computerized axial tomography (CT) c) pos