Attention! 5. Lecture 16 Attention. Science B Attention. 1. Attention: What is it? --> Selection

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1 Lecture 16 ttention Everyone knows what attention is. It is the taking possession by the mind, in clear and vivid form, of one out of what seem several simultaneously possible objects or trains of thought. Focalization, concentration of consciousness are of its essence. It implies withdrawal from some things in order to deal effectively with others William James ttention 1. ttention, selection for awareness 2. Select by feature 3. Select by location. Tracking 5. Spatial resolution of attention 6. Practice, video games Science ttention: What is it? --> Selection ttention selects information for awareness What gets selected (by attention, for awareness)? Many details are processed, few are selected. Metaphors: filter, bottleneck, spotlight Selection filter or bottleneck Sensory Inputs Register features High-level analysis, awareness Slow, serial, limited capacity 3 ttention! 5 Spotlight: location, size, level of detail Some features or events just grab our attention Involuntary attention: orienting reflex Unexpected event, orient body toward the action For vision, the eyes move first: overt orienting ut also covert orienting, or attentional gaze: moving the focus of attention without moving the eyes 5 6

2 Feature selection Location selection G J middle T G X E R E X O X third C R M M Other events are selected voluntarily How many e's are there in the line above? Overt gaze (scan line) vs covert, attentional gaze (fixate t in there above) Whether voluntary or involuntary, attention can select based on either features or location Selection by color 7 Selection based on color is easy Will receptive fields detecting a red stimulus please raise their hands 8 Visual Search 2. Select by feature SY R U V T C W I N IU O L E M Y Y U D O F T K R J D G Selection by location ttend to whole array and the one red, or big, or tilted item rapidly draws attention to itself The features that can be selected so easily may be the primitives of vision, its alphabet ased on receptive field properties -> orientation, size, color, contrast, terminators, motion, depth 9 Your friends with the green scarves at Pamplona jump out at you ut finding a bald man at a rock concert is hard 12

3 For more complex properties, identity not available preattentively Must attend to one item at a time in order to identify each and find target --> slower Visual search experiments One target on half the trials Vary the number of items in display Subject reports whether target is or absent Measure the time from the appearance of the display to the response Selection based on upright vs upside down is not easy 13 3 items target 6 items target absent 10 items target 1 Visual search experiments If reaction time is unaffected by number of distractors (slope=0) Then target identity was available preattentively and drew attention to itself Visual search experiments If reaction time increases with number of distractors Then target not available preattentively, Has to be determined by selecting each item in turn and matching to target Response Time Number of items absent 15 Response Time absent? Number of items absent 16 Feature Integration Theory nne Treisman ut high-level properties may also be easy to find, scene properties like surface curvature from shading ttention selects then binds Select the features Combine them into objects inding only occurs with attention is just a set of unattached features,,,,, before attention arrives. ttention binds them into one object 17 Preattentive identification not limited to properties extracted by cells in striate cortex 18

4 lso the cube with the odd orientation is easy to find Stroop Effect evidence for preattentive processing of unattended words --> very high level Preattentive identification not limited to properties extracted by cells in striate cortex 19 Impossible to ignore meanings of words when attending to their color 20 Stroop Spy Test Selecting from overlapped items ROUGE VERT NOIR JUNE VERT LNC ROUGE VERT NOIR JUNE ROUGE LEIKT GULT SVRT GULT LEIKT HVITT SVRT LEIKT SVRT GULT HVITT Feature based selection can access target even when overlapped by a different item Even when target is a dynamic object or group of objects Selection by Location Normally attend to something by looking right at it ut attention can move independently of eyes Size of selection area is variable (like zoom lens) Fewer items selected means more detail for each item N V K H Z N V K H Z Cueing location to attend sends attention there Find benefits at that location, nd costs elsewhere Y X W Y X W Select only a few, get enough detail for identity Select all and get only positions, not identity 23 2

5 Why should attention move independently of eyes? Useful for _, _ Tracking, individuation Once captured, attention tracks moving and/or changing targets!!. Tracking! Limited resources Multiple targets, same task How many? Multiple tasks at the same time Count backwards and track How many? Tracking 3 balls (!) ttention image Spatial resolution of attention You can shrink the area of selection to be small ut not as small as the smallest detail you can see Q N R H N P G E S D F G L G F K O P E N X S L R F While looking in the center, you can see the bars but you cannot attend to individual bars try counting them without moving your eyes 27 Region of selection can zoom in or out but has a minimum size that is surprisingly coarse Video games and visual attention Decreased academic performance Increased antisocial behavior Increased aggressive thoughts, behavior Smoking, obesity Recruits players and non players, tests them May, 2003 Shawn Green running some attention tasks for cognitive psychology project Notices that some subject are off the scale Questions them They all play video games 29 He finds that players have etter, faster responses in multiple target tests etter resolution of attention (less crowding) Can track more objects in multiple object tracking lso finds that children improve attention skills Why? 30

6 Summary Gamer surgeons, fewer errors, faster responses Do only people with good visuo-spatial skills play games? No, train non-gamers, get advantage after 2 weeks ut only with multitarget, multitasking games, not Tetris ttention skills can be improved with game experience 1. ttention, selection for awareness, bottleneck, spotlight, attentional gaze 2. Select by feature, visual search 3. Select by location. Tracking, capacity, limited resources 5. Spatial resolution of attention 6. Practice, video games 35 1 Minute Quiz Readings for Wednesday, V 11: ; Mid Term next Monday Review Session Saturday 36