Attention. Attention

Transcription

1 Attention What does it mean? PWrite down YOUR definition(s) of attention. PWe ll compare notes, and probably see a variety of different concepts being described Attention Ways of thinking about attention PAttention as arousal PSelective attention < What happens to unattended inputs? < Conscious and unconscious perception < Change blindness < Priming PDivided attention < Limited resources (specific? general?) < Response selection < Automaticity

2 Selection in reading One morning a big poster outside of Oak School folding tables volunteers new textbooks volunteers told people about a basement rummage bargain sale folding tables New textbooks a rummage sale Inside were long counters on which stuff collected a rummage sale new textbooks folding tables by the kids was shown. Price tags were fastened to folding tables volunteers new textbooks rummage all articles. Most of the customers bought old but volunteers new textbooks folding tables rummage useful furniture.the sale was a huge success and sale volunteers new textbook volunteers new money was used to purchase a great many books. Dichotic listening An experimental procedure for studying selection and division of attention Yesterday I bought a big pumpkin... After a while I bin nach hause gehen... Yesterday I bought...

3 Traditional models of selective attention PFilter theory (Broadbent) PAttenuation theory (Treisman) P Late selection theory Figure 4.2 (p. 102) Flow diagram of Broadbent's filter model of attention.

4 Figure 4.3 (p. 103) (a) A sieve that lets through small grains of sand and keeps coarse grains from coming through, based on the physical characteristic of the size of the sand particles. (b) Broadbent's model of attention lets through the attended message and keeps the unattended message from getting through, based on physical characteristics of the message, such as the pitch of a person's voice. Figure 4.6 (p. 106) Flow diagram for Treisman's attenuation model of selective attention.

5 Figure 4.8 (p. 108) Event-related potential (ERP) recorded when a person is selectively at tending to a message (solid color line) and when the person is not selectiv ely attending (dashed black line). The N100 wave, a negative wave that peaks a t 100 msec, is larger when the person is paying attention. Figure 4.9 (p. 109) A difference between the early- and late-selection approaches to selective attention is the characteristics of the messages that are used to accomplish selection. Early selection (Broadbent's approach) is based on physical characteristics. Late selection (Makay's approach) is based on meaning. Treisman's attenuation model falls in between these two because selection can be based on physical characteristics, meaning, or both.

6 Attention can both promote and inhibit processing Limited resource models PConscious expections and unconscious priming PPosner & Snyder experiment, demonstration PHigh validity cue leads to expectation < Which leads to both facilitation and inhibition PLow validity cues does not lead to expectation < Gives facilitation, not inhibition PSearchlight metaphor Posner Experiment A classic design... PTask: tap your chair as soon as you see a target (#) PCue: an arrow (that might be) pointing to where the target appears PManipulation: validity of arrow < Valid, invalid, neutral (no arrowhead) PManipulation: proportion of valid trials < In our demo, 80%

7 Posner findings Automatic priming PFacilitation: faster than neutral condition when arrow points to # < Some facilitation even when arrow is uninformative (arrow lies 50% of the time) (automatic facilitation) < More facilitation when arrow is usually-valid (usually tells the truth) (conscious facilitation) Posner Findings, cont. Strategic/conscious priming PInhibition: slower than neutral when arrow points away from # < But ONLY in usually-valid condition (conscious inhibition) < There is only facilitation, not inhibition, in the uninformative (50-50) condition

8 Figure 4.27 (p. 127) Three models of attention. (a) Spotlight model: Attention is focused on one area; (b) zoom lens model: A spotlight in which the area of attention can be varied to be small or large; (c) object-based attention: Attention is focused on an object and moves with the object. If a resesarcher examines the fate of unattended information, s/he is most likely studying a. vigilance b. divided attention c. selective attention d. visual agnosia

9 The Posner/Snyder visual cueing experiment, demonstrated in class, in which an arrow cue sometimes pointed at a target you had to respond to, showed which of the following phenomena: a. you are unaware of targets you are not attending to b. when the cue is usually valid, your detection of the target is inhibited on gtrials in which the cue points in the wrong direction c. your detection of the target is inhibited on trials in which the cue points in the wrong direction, regardless of the validity of the cue d. a simple target like # pops out and you can respond to it equally quickly regardless of whether or not you have a valid cue about where it will appear. Inattention PAttentional blink < Attending to one stimulus (or making one response?) inhibits attention to the one after it PChange blindness (change detection) < Magic demo < Movies PRelation to eye fixations < Henderson & Hollingworth

10 Attentional blink PYou ll see a rapid series of letters, 100 to 150 ms/letter PYour task: was there a J, a K, or both, or neither? PResult: you were likely to miss a target when it immediately follows another target Magic!

11

12 CogLab Change Detection Flicker No Flicker 0 Flicker No Flicker Accuracy, % Time, sec

13

14 If a researcher examines the fate of unattended information, s/he is most likely studying A) Vigilance B) Selective attention C) Divided attention D) Visual Agnosia

15 The attentional blink experiment demonstrated in class is claimed to show A) You are unaware of unattended stimuli but aware of ones you are looking for B) You are momentarily inattentive to a stimulus that occurs right after a target stimulus C) Your memory for events depends on your ability to subvocally encode them D) You are functionally blind in the period of time when the eyes are making a saccade from one location to another Pathologies of attention P Schizophrenia < McGhie, unable to let normally-automatic processes go on automatically < Maybe unable to control attention selectively < Ordinary skills of living are disrupted PUnilateral neglect < Parietal lobe damage, failure to attend to one hemifield P Blindsight < V1 area damage, but still some residual visual function

16 An interesting link If you would like to look at any of the demonstrations of inattention and change blindness, you can find a link on the Psych 315 web page (under experimental demonstrations) or you could go directly to Divided attention PLimited capacity (or capacities) P Automaticity < Effects of practice PTask specific capacities < Response selector limits

17 Evidence for limited general capacity PPupil dilation effects PEffects of cell phone usage when driving PfMRI measures: more activity in brain area used for one task when done separately than when done with another task Example of capacity limitation Nonautomaticity PCell phone use during driving < Quadruples accident rate < 20-30% of all crashes occur during cell phone use But may not be causal; just correlational < URI study Eye movements while driving and using cell phone (or doing other capacity-demanding tasks < University of Utah, Canadian studies Respond (e.g. brake) to signal (e.g. red light)

18 Automaticity Remember the Stroop test? PAutomatic processes don t take capacity < Don't interfere with other processes PAutomatic processes don t need intention < Irresistable reflex PAutomatic processes are/can be unconscious < You may be unaware of them Practice and automaticity PHighly practiced tasks may be automatic < Stroop task PExperimental demonstration of the effects of practice on automaticity < The Schneider and Shiffrin experiment

19 The Schneider and Shiffrin experiment PVisual search task; 1-4 target items in memory, 1-4 items in visual array PVariable mapping: different target items each trial < Conscious search: RT gets longer with more visual items PConstant mapping: same target items for hundreds of trials < Pop-out! Parallel search, automatic Figure 04.07

20 Practice in coordinating tasks Spelke, Hirst, & Neisser PWriting to dictation + reading stories PPractice for 6 weeks PLearn channel segregation: keep two tasks from intefering with each other Lee Brooks experiment PImagine capital F; mentally walk around it, classifying each corner as inside or outside PVisually guided response: for each corner, point to I or O (inside/outside) in visual array PLinguistic response: say inside or outside for each corner PWhich is harder? Why?

21

22 As you work around the F, decide whether the first corner is an INSIDE or an OUTSIDE, and point to the I or the O on line 1; then do the same for the second corner on line 2, etc.) 1. O I 2. I O 3. O I 4. O I 5. O I 6. I O 7. I O 8. O I 9. O I 10. I O

23 1. O I 2. I O 3. O I 4. O I 5. O I 6. I O 7. I O 8. O I 9. O I 10. I O As you work around the F, decide whether the first corner is an INSIDE or an OUTSIDE, and point to the I or the O on line 1; then do the same for the second corner on line 2, etc.) 1. O I 2. I O 3. O I 4. O I 5. O I 6. I O 7. I O 8. O I 9. O I 10. I O

24

25 As you work around the F, decide whether the first corner is an INSIDE or an OUTSIDE, and point to the I or the O on line 1; then do the same for the second corner on line 2, etc.) 1. O I 2. I O 3. O I 4. O I 5. O I 6. I O 7. I O 8. O I 9. O I 10. I O

26 As you work around the F, decide whether the first corner is an INSIDE or an OUTSIDE, and point to the I or the O on line 1; then do the same for the second corner on line 2, etc.) 1. O I 2. I O 3. O I 4. O I 5. O I 6. I O 7. I O 8. O I 9. O I 10. I O

27 Some individuals with damage to the parietal lobe are apparently unaware of one side of the world (e.g., the left hemifield). This disorder is called A) unilateral neglect B) blindsight C) split brain syndrome D) visual agnosia Your lecturer described some recent research showing the attentional problems caused by cellphone use while driving, and interpreted them in terms of A) capacity limitation B) overuse of the articulatory loop C) attenuation theory D) Broadbent's filter theory