Introduction to Attention and Theories of Selective Attention

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1 Introduction to Attention and Theories of Selective Attention Psychology 355: Cognitive Psychology Instructor: John Miyamoto 04/09/2018: Lecture 03-1 Note: This Powerpoint presentation may contain macros that I wrote to help me create the slides. The macros aren t needed to view the slides. You can disable or delete the macros without any change to the presentation.

2 Outline Humans are limited capacity information processors Capacity limitations shape the mental strategies that humans use. Examples of capacity limitations in human information processing Selective attention is one of many human adaptations to limits in human information processing. Lecture probably ends here Theories of selective attention. Psych 355, Miyamoto, Spr '18 Example 1: Capacity Limitation in Spatial Attention 2

3 Example 1: Attention To a Location Enhances Information Processing at that Location Information processing is superior when the subject pays attention to only a few locations. Information processing is inferior when the subject is required to pay attention to a larger number of locations. Psych 355, Miyamoto, Spr '18 Display Array of Multiple Locations 3

4 Searching Multiple Locations for a Target Letter o indicates a possible position for the target letter. Psych 355, Miyamoto, Spr '18 Same Display with Numbers that Label Positions 4

5 Searching Multiple Locations for a Target Letter Numbers are labels for positions. + Psych 355, Miyamoto, Spr '18 Start Trial 1 5

6 Trial 1: Target Letter is F An array of letters will appear when I click the slide. Identify the location of the letter F. Where was the F? Psych 355, Miyamoto, Spr '18 Trial 1 Solution 6

7 Trial 1 Solution: Target Letter is F Psych 355, Miyamoto, Spr '18 Start Trial 2: Another Example of a No Cues Trial 7

8 Trial 2 (NO CUES): Target Letter is F An array of letters will appear when I click the slide. Identify the location of the letter F. + Where was the F? Psych 355, Miyamoto, Spr '18 Identify the Correct Response to Trial 2 8

9 Trial 3 (NO CUES): Target Letter is F + Where was the F? Psych 355, Miyamoto, Spr '18 Explain Cueing for Potential Target Location 9

10 Cueing the Potential Target Position Just before the target array is displayed, you will see 2 circles that indicate the potential location of the target. Psych 355, Miyamoto, Spr '18 Letter Array for Cueing Example 10

11 Task: Find the F B Psych 355, Miyamoto, Spr '18 Trial 4 with Cues for Target Position 11

12 Trial 4: Target Letter is F Get ready for the cues and the letter array. Psych 355, Miyamoto, Spr '18 Trial 4 Solution 12

13 Trial 4 Solution: Target Letter is F + Psych 355, Miyamoto, Spr '18 Conclusion: Increasing the Target Locations Makes the Task More Difficult 13

14 Psych 355, Miyamoto, Spr '18 14 Question to Class: Which Demo to Use? Conclusion from Demonstration 1 Letter detection is hard when we attend to many locations. Letter detection is easier when we attend to only a few locations. Rate and quality of perceptual information processing increases when we know where to focus attention. Duh? If we couldn t focus attention, we couldn t benefit from the improved perceptual processing when attention is focused.

15 Ask Class: Have They Seen Dan Simon's Famous G-r---a Study Should I show the G study or the D study? Raise your right hand if you have seen a video that is associated with: Dan Simon (psychologist) Students bouncing a basketball in an office building Students wear black tee shirts or white tee shirts Should you focus talk on G study or D study? Psych 355, Miyamoto, Spr '18 Demonstration 2: Basketball in the Hallway 15

16 Example 2 Show in browser 1:21 length When I switch to the browser, you will see a short video that shows two groups of people passing basketballs back and forth. One group wears white tee shirts; the other group wears black tee shirts. Each group has a basketball and the group members pass the ball back and forth to other group members. Note to self: Start at 11 seconds. Pause at 11 seconds. Note to self: Stop demo at Time = 41 seconds Psych 355, Miyamoto, Spr '18 Task Instructions 16

17 Classroom Demonstration Your Task YOUR TASK: Count... 1)... the number of times someone in a WHITE shirt passes the ball to another person in a WHITE shirt, PLUS... 2)... the number of times someone in a WHITE shirt bounces the ball on the ground, either to themselves or to a team mate. The activities of people in BLACK are not relevant to this task. TASK = Count PASSES + BOUNCES of people in white shirts NOTE: The video only asks you to count the number of passes; I want you to count the number of passes plus the number of bounces. Psych 355, Miyamoto, Spr '18 Correct Answer for PASSES + BOUNCES 17

18 Questions for the Class How many times did the people in the white tee shirts pass the ball or bounce the ball? 15 Passes + 10 Bounces = 25 Passes & Bounces Did you notice anything else that was strange? Raise your hand if you noticed anything strange about the video. Only people who got the total number of passes and bounces can answer the question about what was strange! Repeat video Psych 355, Miyamoto, Spr '18 Attention & Capacity Limits Are Complementary Aspects of Cognition 18

19 The Door Study Very funny recreation of the Door study: Original Door Study (one example): Psych 355,, Miyamoto, Spr '18 19

20 Attention & Capacity Limits Are Complementary Aspects of Cognition We need attentional functions because we have information processing limitations. Attentional functions enhance information processing despite our capacity limits. (Comment on limitations on working memory) Psych 355, Miyamoto, Spr '18 Quotation from C. Eastwood 20

21 A man's got to know his limitations Actor: Clint Eastwood Role: Harry Callahan Movie: Magnum Force Psych 355, Miyamoto, Spr '18 YinYang of Attention & Cognitive Resource Limitations 21

22 Attention x Capacity Limits: Complementary Aspects of Cognition Attention Cognitive Capacity Limitations Psych 355, Miyamoto, Spr '18 Human Are Limited Capacity Information Processors 22

23 Psych 355, Miyamoto, Spr '18 23 Shadowing & Dichotic Listening Humans Are Limited Capacity Information Processors Humans cannot encode and represent ALL of the perceptual information available to them. Selective attention performs two cognitive functions: Selection of the information for thorough processing Neglecting or excluding other parts of the information. Main Question of Remainder of this Lecture: Where does selection occur? Does selection occur near the sensory periphery? Does selection occur after higher processes like meaning-extraction and pattern recognition have begun to take place?

24 "Shadowing" During Dichotic Listening Study Dichotic Listening Listening with 2 ears Monotic Listening Listening with 1 ear "Shadowing" Subject is instructed to repeat out loud the message(s) in one ear, e.g., left ear only. Results for Shadowing Psych 355, Miyamoto, Spr '18 24

25 Shadowing While Engaged in Dichotic Listening: Results Participants could not report the content of the message in unattended ear Knew that there was a message, but had no idea what it was Knew the gender of the speaker Did not know that the same word was repeated 35 times Unattended ear is being processed at some level Cocktail party effect Change in gender is noticed Change to a tone is noticed How to explain the lack of awareness regarding information in the unattended ear? Psych 355, Miyamoto, Spr '18 Attentional Filter What Is It? 25

26 Attentional Filter Filter Hypothesis: There is a cognitive mechanism called a "filter" that allows some sensory inputs to pass to deeper levels of processing, and blocks other inputs from continued processing. Where is the attentional filter in the cognitive process? Inputs Filter Early selection model: Intermediate selection model: Broadbent s filter model Treisman s attenuation theory Late selection model: McKay (1973) Psych 355, Miyamoto, Spr '18 Broadbent's Filter Model: An Early Selection Theory 26

27 Broadbent's (1958) Filter Model (Early Selection Model) Messages: Sensory memory Filter: Detector: Short-Term Memory Psych 355, Miyamoto, Spr '18 Broadbent's Filter Model Messages & Sensory Memory 27

28 Broadbent's (1958) Filter Model Messages: Information coming in from the environment. Sensory memory: Temporary, high capacity information storage. Information is transcient. Only physical properties of stimulus are processed here. A.k.a. "sensory store," "iconic store" for vision; "echoic store" for audition. Psych 355, Miyamoto, Spr '18 Broadbent's Filter Model Filter 28

29 Broadbent's (1958) Filter Model Messages: Information coming in from the environment. Sensory memory: Transient, high-capacity sensory storeage Filter: Blocks most input messages, but lets one (and only one) message pass through. Broadbent s filter model assumes that: a) The filter blocks unattended messages in terms of their physical characteristics, not in terms of meaning. b) It takes time to switch attention from one message to another. Psych 355, Miyamoto, Spr '18 Broadbent's Filter Model Detector & STM 29

30 Broadbent's (1958) Filter Model Messages: Information coming in from the environment. Sensory memory Filter: Blocks most input messages, but lets one pass through. Detector: High quality processor of the message that was selected by the filter. Short-Term Memory: Active processing of information that has passed through the filter (the attended message). Broadbent s Split Scan Experiment Psych 355, Miyamoto, Spr '18 30

31 Broadbent's (1958) Split-Scan Experiment 1. M H Trials 1, 2 & 3 occur in rapid succession. Cond 1: Report letters in any order. 2. R S Typical Result: Subjects says: "M, R, W", then "H, S, P". 65% correct W P Cond 2: Report letter pairs for each trial (pair 1, then pair 2, then pair 3) TypicalResult: Subjects says: "M, H", "R, S", "W, P". 20% correct. Subjects say Cond 2 is more difficult than Cond 1. Psych 355, Miyamoto, Spr '18 How does Broadbent's filter model explain this pattern of results? 31

32 Monday, 9 April, 2018: The Lecture Ended Here Psych 355,, Miyamoto, Spr '18 32

33 How does Broadbent's (1958) filter model explain this pattern of results? Psych 355, Miyamoto, Spr '18 33 Problems with Broadbent's Filter Model Switching attention requires a change (retuning) of the filter. This takes time and cognitive effort. Cond 1 requires 1 switch of attention; M H Cond 2 requires 5 switches of attention. Therefore Cond 2 is harder (more errors; feels more difficult). R W S P

34 Problems with Broadbent's Filter Model Problems with Broadbent s filter model are due to the assumption of early selection (selection precedes the extraction of meaning). Cocktail Party Phenomenon: People remember hearing their own name even if it is presented in the unattended ear. Broadbent's filter model says that unattended messages are completely blocked. Cocktail Party Phenomenon should not occur. Gray & Wedderburn's (1960): "Dear Aunt Jane" experiment Grey & Wedderburn Dear Aunt Jane Experiment Psych 355, Miyamoto, Spr '18 34

ATTENTION! Learning Objective Topics. (Specifically Divided and Selective Attention) Chapter 4. Selective Attention

ATTENTION! Learning Objective Topics. (Specifically Divided and Selective Attention) Chapter 4. Selective Attention ATTENTION! (Specifically Divided and Selective Attention) Chapter 4 Learning Objective Topics Selective Attention Visual Tasks Auditory Tasks Early vs. Late Selection Models Visual Search Divided Attention