Lecture Outline, Chapter 21, The Resting Brain, Attention, and Consciousness INTRODUCTION 1. Introduce the chapter by defining attention. (Refer to PowerPoint slide 2.) Teaching Suggestion: Ask the students to role-play the following situation in order to understand the selective processing of simultaneous sources of information: Jeff is at a party surrounded by loud music and lot of people. Even though he is bombarded by sounds from all directions, he is able to concentrate on the conversation he is having with Anne. He ignores most of the other noises and conversation and pays attention to Anne. Suddenly, he hears Sarah, who is standing behind him, mention his name in passing, and he wants to listen in on what she is saying. Without turning around, he starts focusing attention on this other conversation to find out what’s being said about him. Discussion Point: In an interactive session with students, discuss the given incident with regard to the following: 1) Selective attention that involves interactions between sensory modalities 2) Preferential processing of sensory information RESTING STATE BRAIN ACTIVITY 2. Explain the concept of resting state brain activity. (Refer to PowerPoint slide 3.) Discussion Point: Ask students to explain what the primary evidence is for areas of the brain being active in the resting state. 3. Explain the brain’s default mode network and describe areas of the brain that are active in the resting state. (Refer to PowerPoint slides 4 and 5.) Teaching Suggestion: Using Figure 21.1, discuss PET imaging studies that revealed areas of the brain more active in the resting state than during behavioral tasks. 4. Explain the functions of the default mode network. Discuss the sentinel hypothesis and the internal mentation hypothesis of the function of the default mode. (Refer to PowerPoint slide 6.) ATTENTION 5. Explain the significance of attention for carrying out behavioral tasks and differentiate between bottom-up and top-down attention. Why does attention have limited capacity? Describe the attention-deficit hyperactivity disorder (ADHD) in relation to the limited capacity of attention. (Refer to PowerPoint slide 7.) Teaching Suggestion: Use an example to explain the role of attention. Explain how a person performing an attention-demanding visual task, such as reading, would be less sensitive to incoming sounds. 6. Describe the behavioral consequences of attention. Explain how attention can enhance visual sensitivity by improving target detection and increasing the speed of reaction times. (Refer to PowerPoint slides 8 to 10.) Discussion Point: In an interactive session with students, discuss what happens to cortical activity when the individual directs attention to a task? Teaching Suggestion: Using Figures 21.4 and 21.5, explain the experiment studying the effects of directing visual attention to different locations and the effect of cueing on target detection. Discuss the results of experiment with the students. Using Figure 21.6, explain the experiment, which shows that attention speeds reaction time when performing perceptual tasks. Discuss how attention can alter the speed of visual processing, assuming attention to visual objects does not have a direct effect on visual transduction or motor coding. 7. Explain the concept of shifting attention. Discuss the effects on the brain of shifting attention from one task to another. (Refer to PowerPoint slide 11.) Teaching Suggestion: Explain the concepts of shifting attention by asking students to describe examples of using the “spotlight of attention.” 8. Describe how fMRI imaging has been used to study attention to location and PET imaging to study attention to visual features. (Refer to PowerPoint slides 12 to 14.) Teaching Suggestion: Using Figure 21.8, explain how we are able to pay attention to particular visual features such as color and this attention can enhance performance. Describe the PET imaging experiments done to study brain activity in humans performing a same– different discrimination task. Using Figure 21.9, explain that different areas of cortex are more or less active, depending on the characteristics of stimuli being attended to. 9. Explain enhanced neuronal responses in parietal cortex. Describe the activity of cells in the parietal cortex in response to eye movements, with reference to the studies of tasks involving visual saccades. (Refer to PowerPoint slides 15 and 16.) Teaching Suggestion: Using Figures 21.10 and 21.11, discuss the relationship between attention and eye position. 10. Explain the experiments of Desimone, which show receptive field changes that occur in area V4 in response to attention. (Refer to PowerPoint slide 17.) Teaching Suggestion: Using Figure 21.12, discuss the specific effects of attention on the response properties of neurons in visual cortical area V4. Explain that detection is enhanced at attended locations compared to unattended locations. 11. Discuss the brain circuits that control the directing of attention. Define the pulvinar nucleus. (Refer to PowerPoint slide 18.) Teaching Suggestion: Using Figure 21.13, describe the pulvinar nucleus, its properties, and its possible role in guiding attention. Discuss the experiment in which injections of muscimol (a GABA agonist) or bicuculline (a GABA antagonist) into the pulvinar nucleus suppresses or enhances, respectively, the activity of neurons in this cell group. Discuss the behavioral consequences of such manipulations. 12. Explain how attention and eye movements are interrelated. (Refer to PowerPoint slides 19 to 21.) Teaching Suggestion: Using Figure 21.14, define frontal eye fields. Describe the direct connection between FEF and cortical areas such as V2, V3, V4, MT, and parietal cortex, which influence attention. Using Figure 21.15 and 21.16, discuss the experimental findings on the effects of electrical stimulation of the FEF. Elucidate the functions of FEF. 13. Explain directing attention with salience and priority maps. Discuss how salience maps are used in bottom-up attention and priority maps in top-down attention. (Refer to PowerPoint slide 22.) 14. Describe area LIP and explain the function of priority maps in the parietal lobe. (Refer to PowerPoint slide 23.) Teaching Suggestion: Using Figure 21.18, describe the location of area LIP. Explain that lesions in parietal cortex are associated with neglect syndrome. Teaching Suggestion: Using Figure 21.19 and Figure 21.20, describe the evidence for a bottom-up priority map and a top-down priority map in area LIP. 15. Explain hemispatial neglect syndrome as an attentional disorder. (Refer to PowerPoint slide 24.) Teaching Suggestion: Explain the cause of the neglect syndrome. Using the paintings in Figure A in Box 21.2, discuss the symptoms of this syndrome. 16. Explain the brain areas involved in the frontoparietal attention network. Discuss its function. (Refer to PowerPoint slides 25 and 26.) Teaching Suggestion: Using Figure 21.21, describe the location of the frontoparietal attention network in the macaque brain. CONSCIOUSNESS 17. Explain two perspectives on the nature of consciousness. Discuss the problems of understanding and studying consciousness. (Refer to PowerPoint slides 27 and 28.) Discussion Point: Ask students to distinguish between the materialist and dualist perspectives on consciousness. 18. Identify the “easy” and “hard” problems of consciousness. Define the concept of neural correlates of consciousness and explain why this study is of interest to neuroscientists. (Refer to PowerPoint slide 29.) Teaching Suggestion: Using Figure 21.22, describe how neural correlates can be understood with a bistable visual image. 19. Explain how experiments using binocularity and rivalry have been performed to study neural correlates of consciousness. (Refer to PowerPoint slides 30 and 31.) Discussion Point: Using Figure 21.24, discuss how this experiment involving binocular rivalry demonstrates different neural correlates. 20. Explain the challenges of studying consciousness. Discuss technical issues involved in studies attempting to understand conscious experiences. (Refer to PowerPoint slide 32.) CONCLUDING REMARKS 21. Conclude the chapter by summarizing what is understood about the brain’s resting state and the neural processes of attention. (Refer to PowerPoint slide 33.) Discussion Point: In an interactive session with students, talk about how attention provides a powerful reminder of the flexibility of the human brain. 22. Discuss how consciousness is as difficult in neuroscience as it is in philosophy. Ask students if they think the “hard problem” of consciousness will ever be solved. (Refer to PowerPoint slide 33.) Discussion Point: Ask students if, on the assumption that the materialist perspective of consciousness is correct, they think computers will ever be conscious in the same sense that humans are.