Attention. What is it? What control do We have over it? cogch3 Attention 1

Transcription

1 Attention What is it? What control do We have over it? cogch3 Attention 1

2 Everyone knows what attention is. It is the taking of 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 more effectively with others, and is a condition which has a real opposite in the confused, dazed, scatterbrained state which. Is called distraction. - William James (1890) cogch3 Attention 2

3 Read the bold print. Somewhere Among hidden the in most the spectacular Rocky Mountains cognitive near abilities Central City is Colorado the an ability old to miner select hid one a mes sage box from of another. gold. We Although do several this hundred by people focusing have our looked attention for on it, certain they cues have such not as found type it style. What do you remember from the regular print text? What does this tell you about selective attention? cogch3 Attention 3

4 Views of Attention As an Information Filter As a Limited Resource As Mental Resource Attention as a Feature Binder cogch3 Attention 4

5 Attention as Information Filter Attention serves to pare down the vast amount of information in our environment (sensed) to just a small amount we can focus on. cogch3 Attention 5

6 Attention Perceptual processes - Parallel & Unlimited Attention - Serial and Limited At some point there is a bottleneck. cogch3 Attention 6

7 We need to select which input will be attended to (and further processed) and which will be ignored (and lost). Questions 1) Is bottleneck before or after meaning has been processed? 2) How do we select what to attend to? cogch3 Attention 7

8 Where is the filter? If early, it blocks out a lot of information, but it saves the cognitive system the work of having to process ALL input. cogch3 Attention 8

9 Dichotic Listening Task (Cherry, 1953) - two messages presented Shadowing task - repeat message presented in one ear as you are hearing it. Dependant Measures 1) Shadowing performance (errors, hesitations, omissions) indicate that attention has been diverted. 2) What is recalled from the unattended message? cogch3 Attention 9

10 Dichotic Listening Task cogch3 Attention 10

11 Dichotic Listening Results Physical attributes of unattended channel are detected (e.g., Male. vs. female voice; Human vs. musical instruments). Semantic (meaning) attributes of unattended channel were missed (e.g., Don t notice switch to foreign language). No content was remembered, even when the unattended stream was the same word presented 35 times (Moray, 1959). cogch3 Attention 11

12 What it tells us about the filter Early selection for physical features (location, color, pitch of voice) but filtering does not occur due to meaning. Further studies, however found that some meaningful words do capture some peoples attention. cogch3 Attention 12

13 Moray (1959) - cocktail party effect subjects could often (1/3 of time) detect their own name, fire or context relevant words on unattended channel. How could this happen if unattended information does not pass through filter for pattern recognition? cogch3 Attention 13

14 Why do only some people notice relevant unattended words? Conway, Cowan & Bunting (2001) Working Memory (WM)capacity Gave participants a task that taxes WM capacity (math verification task plus word memory) to measure WM capacity. Those who detect their name in the irrelevant message have relatively low WM capacities, suggesting that they have difficulty blocking out, or inhibiting, distracting information. cogch3 Attention 14

15 Results Those who detect their name in the irrelevant message have relatively low WM capacities, suggesting that they have difficulty blocking out, or inhibiting, distracting information. cogch3 Attention 15

16 Salience The meaningfulness of the information at the moment. For example, you might pass by an advertisement for snacks everyday without noticing, but if you are hungry, it will grab your attention. cogch3 Attention 16

17 Treisman (1960) Found that attention could be easily switched to the unattended ear when semantic content of the message shifted cogch3 Attention 17

18 Problem Does this require that all information would have to be processed for meaning (very labor intensive). This leaves us with the question of why, if the system is doing all this work to process for information, why it then gets blocked from further awareness. cogch3 Attention 18

19 Treisman Attenuation Model Attenuation = loss of signal strength Cogch4 Attention 19

20 The Dictionary Unit Both messages gets passed on to the dictionary unit Threshold = Smallest signal strength that can just be detected Easily detected cogch3 Attention 20

21 Attention as a Limited Resource Spot Light/Zoom Lens Metaphor Can be directed to specific areas Can be diffuse or focused - trade off in concentration Automatic of consciously directed Limited capacity cogch3 Attention 21

22 Spotlight is flexible Experimental subjects can control whether they focus on a specific target (the middle letter of a five letter word) or spread their attention (across all the letters. La Berge, 1983) cogch3 Attention 22

23 LaBerge (1983) Participants complete one of two tasks per trial The primary task required subjects to categorize (a) fiveletter words, or to categorize the middle letter of (b) five-letter words or (c) five-letter nonwords. The probe task required the subjects to respond when the digit 7 appeared in one of the five letter positions. cogch3 Attention 23

24 Evidence in Favour of the Zoom-lens Model Mean reaction time to the probe as a function of probe position. The probe was presented at the time that a letter string would have been presented. Data from LaBerge (1983).

25 Attention as mental Resource Attention is more like a limited resource Kahneman s (1973) capacity theory When a particular task demands lots of processing resources, then other tasks get fewer resources. No task Hard task Easy task Attention capacity

26 Allocation of attention is intentional Depends on Interest Arousal level Complexity of the task Distractors cogch3 Attention 26

27 Dual Task vs. Single Task Studies Strayer and Johnson (2001) Volunteers perform a simple simulated driving task (using a joystick to make a cursor to follow a dot moving randomly back and forth across the screen). At random intervals, the dot would turn either green or red. On a red light, participants were supposed to press the brake button on the joystick. cogch3 Attention 27

28 After practice a secondary task was added: DV reaction to red light. Found no difference between people who used a handheld or hands-free cell phone. no difference between radio/audiobook listeners and the driving-only condition. However, the cell-phone talkers missed more than twice as many red lights as the other participants. cogch3 Attention 28

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30 In addition to the accuracy problems, cell phone users also showed slower reaction times compared to when they were driving alone. cogch3 Attention 30

31 Why, are conversations distracting? In a second experiment, they had participants drive over easy and difficult courses. The volunteers were first asked to simply repeat words to the experimenter over the telephone. Next they were asked to generate a new word starting with the last letter of the word the experimenter gave them (for example if the experimenter said salmon, the volunteer could respond night ). cogch3 Attention 31

32 Results No significant difference in errors on the easy course. On the difficult course, when drivers had to generate words in response, they made significantly more errors cogch3 Attention 32

33 So the key seems to be not simply that drivers are having a conversation, but that they are actively generating responses. Not Fun Facts: Cellphone use increase the risk of crashes to the same level as a BAC of % of crashes and 67% of near crashes involve distracted drivers. cogch3 Attention 33

34 Cell Phone Use (another study) Hyman et al. (2009) Cell phone users less likely (25%) than non-users (51%) to notice a unicyling clown!!! cogch3 Attention 34

35 2012 National Survey on Distracted Driving Attitudes and Behaviors Nearly half (48%) of drivers admit to answering their cell phones while driving. Of those who answered their phones while driving, 58% of drivers continued to drive while talking on the phone. In the survey, 24% of drivers reported that they are willing to make a phone call while driving. One in 10 drivers surveyed said that, at least sometimes, they send text messages or s while driving. Of the drivers surveyed, 14% said they read text messages or s while driving. A majority of respondents supported laws that banned talking on cell phones, texting, or ing while driving.

36 2012 Texting Pedestrian Study Researchers from the University of Washington monitored 20 of Seattle's busiest intersections and observed the following: Pedestrians who text are 4x less likely to look before crossing the street, cross in crosswalks, or obey traffic signals. They also found that texting pedestrians take an average of two seconds longer to cross the street.

37 Multi-tasking Ophir et al. (2009) Correlation between multitasking and distractibility. When asked to do two tasks at once, participants who reported being multitaskers performed less well on the main task than did non-multitaskers. Perhaps multi-taskers are just less able to focus attention. cogch3 Attention 37

38 Attention as a Feature Binder Treisman Feature Integration Model of Attention Remember the What and the Where/How systems we discussed in the last chapter. This view of attention suggest that features are detected by the What system automatically (without drawing on attentional resources). Binding information together using both the What and the Where/How systems requires attentional resources.

39 Demonstration I will show you a scene quickly. Report first the black numbers. Report what you see at each of the 4 locations. +++ Mask

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43 Report first the black numbers. Report what you saw at each of the 4 locations.

44 Illusionary conjunctions We tend to put different features from different objects together. Some brain damaged patients (parietal lobe) show illusionary conjunctions even when the patients were allowed to view the stimuli for 10 seconds.

45 Feature Integration Theory Find the Green X X X X X X X X X XX X X X X X O X O X O O X X O XO X Feature search Conjunction search Treisman & Gelade 1980

46 Find Which is more difficult?

47 Find Which is more difficult?

48 Typical Findings & interpretation RT (ms) Feature Target Conjunction Feature targets pop out flat display size function Conjunction targets demand serial search non-zero slope Display Size

49 Feature integration theory Attention is the glue that combines the information from the what and where systems.

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51 Neuroscience support for FI theory. The brain area that appears to be responsible for binding features is located in the right Parietal Cortex.

52 Zaretskaya et al. (2013) Participants viewed stimuli depicting either local feature movement or global feature movement. Comparing fmri Images revealed that integration of the global features differed from local features by activity in the right Parietal Lobe (last slide).

53 Attentions Effects on Perceptions The test Explanation

54 The Simon Effect Demonstration Another Demonstration

55 Why? Attentional Movement Hypothesis Simon (1969) proposed that the effect was due to a primitive tendency to react toward the source of stimulation, a kind of orienting reflex which facilitates actions towards, and interferes with actions away from the stimulus. In other words, as attention moves to one side or the other, it biases the responder towards responding to the side attention has been shifted to. In order to over-ride that reflex, the responder must suppress the reflex and select the correct answer, thus slowing down their response time in the inconsistent trials.

56 Alternative Explanation Referential-coding Hypothesis Spatial stimulus coding depends on the availability of frames or objects of reference rather than on certain attentional movements. Regardless of the explanation, the Simon Effect shows that location information cannot be ignored and will affect decision making, even if the participant knows that the information is irrelevant.

57 The Effects of Automatic Processes on Attention The Stroop Effect (1935) Why? Reading in your native language is Automatic. The name of the word and the color of the font are both activated and compete as responses, slowing down your ability to respond when the two pieces of information conflict. Link to try a quick test on your own

58 Automatic vs. Controlled Processes Automatic Processes No attentional resources Fast and efficient Unavailable to consciousness Unavoidable Unintentional Video Controlled Processes Takes attentional resources Slow and less efficient Available to consciousness Controllable Intentional

59 Factors that effect Automaticity Practice and Experience - Children who do not read fluently do not show Stroop effects - Driving at first it takes a lot of attention and distractions interfere with performance, but with experience the processes become automated (both good and bad driving habits).

60 Have you ever driven somewhere you did not intend to go? (literally, autopilot) Sometimes automatic processes once cued, continue to completion while our controlled processes are busy thinking of other things.

61 Divided Attention Can Be Achieved with Practice Schneider and Shiffrin (1977) Divide attention between remembering target and monitoring rapidly presented stimuli Memory set: 1-4 target characters Test frames: could contain random dot patterns, a target, distractors

62 Caption: Consistent mapping condition for Schneider and Shiffrin s (1977) experiment.

63 Conditions Consistent Mapping Condition the targets were of a different type than the distractors (e.g., targets were number and distractors were letters). - hypothesis: this condition would be easier and show improvement with practice. Varied Mapping Condition targets and distractors were of the same type. - hypothesis: this condition was predicted to be more difficult

64 Conditions Continued Number of Targets was also manipulated had to monitor for between 1 to 4 targets. Hypothesis: the more targets the more difficult. The number of distractors Hypothesis: the more distractors the more difficult. Display time Hypothesis: the faster the presentation rate the more difficult

65 Results: Consistent Condition Consistent was easier than Varied condition and improved over trials Beginning trials: 55% accurate 900 Trails: 90% accurate 600 Trials: Participants reported automatic processing. Not effected by target set size, number of distractors but was small effect of presentation time.

66 Varied Condition Less accurate, effected by target number, distractor number and presentation rate. Did not become automatic.

67 After 2100 trials they reversed the target and distracter sets. Consistent Condition Automatic processes from first 2100 trials interfered with performance. Performance showed controlled processes. Varied Condition No Interference this more difficult task did not become automated.

68 Instance Theory of Automaticity (Logan, 1992) For certain tasks at least you can think of automatization as arising from a race between memory and a procedure. Consider addition: "What is ?" If you've solved this problem before you can get this information from memory. Or you can work out a solution the long way.

69 Logan assumes that each time you solve the problem you get a new instance of the problem stored in memory. Its like finding a needle in a haystack. If there's only one needle its hard to find. But if there are 100 needles its much easier to find. Logan's model is self-terminating and parallel. This means that you are both trying to work out the solution the long way and retrieve it from memory at the same time. As soon as you determine a solution (whichever way you do it) you stop working on the problem. Skills become increasingly automatic as more and more instances are added to memory and it becomes increasingly likely that the problem will be solved by memory.

70 Pluses and Minuses of automatic processing Pluses of automaticity Allows people to perform multiple tasks at a time. Allows people to build complex skills. Minuses of automaticity Sometimes people can make careless mistakes. Sometimes people can miss details:

71 Attention as executive control In contrast to capacity theories (which see attention as a limitation) considering it as executive control of possibly conflicting multiple goals makes attention instead a source of efficiency Evidence: Psychological Refractory Period

72 Practice and Dual Task Performance Spelke, Neisser et al. (1976) Two subjects read short stories while writing lists of words at dictation. After some weeks of practice, they were able to write words, discover relations among dictated words, and categorize words for meaning, while reading for comprehension at normal speed. The performance of these subjects is not consistent with the notion that there are fixed limits to attentional capacity. cogch3 Attention 72