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9am

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9am

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  1. 9am

  2. Attention • Difficult to define - like nailing jello to the wall. • Goldstein defines it as: • the process of concentrating on specific features of: • the environment • thoughts or activities • what then is concentrating? • focusing attention Some Examples • Dodging kids that run out into the street • Reading and listening to music • Daydreaming and not hearing someone talking to you (a.k.a. “spacing–out”) Attention is involved in: • Perception • Memory • Language • Problem solving

  3. Selective Attention • Loosely defined: the ability to focus on only one thing. • For example, spacing out – staring at the TV and not hearing the phone ring. Dichotic Listening Tasks (Cherry, 1953) • 2 messages presented - one in each ear • Shadowing: ‘attend to’ and repeat one message • Didn’t retain much from the ‘unattended’ message - even when repeated 35x cocktail-party phenomenon Broadbent’s Filter Model (1958) • human as information processor 10-15 sec < 1 sec

  4. messages sand sound filter size selection attended message fine grain sand Broadbent’s Filter Model (1958) • early selection model: filter before meaning generated voice pitch speed accent meaning

  5. Broadbent (1958): split-scan experiment • Cond-1 = 65% accuracy • Cond-2 = 20% accuracy CONDITION 1: repeat in any order Typical answers: MRW; HSP CONDITION 2: repeat each pair, as presented Typical answers: MH; RS; WP Assumption: -ears as separate channels -switch is costly

  6. Flaws in the Filter Model (Gray & Wedderburn, 1960) Meaning trumps filtering & switching Explanation: No switching, because no channels Meaning processed before filtering Moray (1959): own name heard in unattended ear is remembered

  7. Only attended message should get through! “LEAKY FILTER” MODEL (ATTENUATION THEORY): Treisman (1964)

  8. Attenuator Analyze incoming message in terms of: • Physical characteristics • Language • Meaning Just enough processing to distinguish different incoming messages

  9. The Dictionary Unit • Like a memory • Contains stored words that have thresholds for being activated • Lower thresholds mean more sensitive Signal strength own name Rutabuga boat Treisman would say your name has a low threshold

  10. 10am

  11. “river” or “money” (biasing words) “They were throwing stones at the bank.” Attend Left LATE-SELECTION MODELS: Mackay (1973) experiment TEST: “They threw stones toward the side of the river yesterday.” “They threw stones at the savings and loan association building yesterday.” Which sentence is closest in meaning to the attended sentence?

  12. TREISMAN BROADBENT MACKAY

  13. EASY RT (ms) C I DIFFICULT RT (ms) C I Early- or late-selection models? Crucial variable for both: task load (cognitive resources) FLANKER-COMPATIBILITY TASK (Green & Bavelier, 2003):

  14. LOW-LOAD LOW-LOAD RT (ms) RT (ms) C I HIGH-LOAD HIGH-LOAD C I RT (ms) RT (ms) C I C I CONTROL VIDEO GAME PLAYERS

  15. Lavie (2005): EARLY-SELECTION MODELS use HIGH-LOAD tasks LATE-SELECTION MODELS use LOW-LOAD tasks DIVIDED ATTENTION Spelke (1976): simultaneously read and take dictation DAY 1: can do both separately; not simultanously After 85 hours of practice: can do both at the same time

  16. Schneider & Shiffrin (1977): -detecting ‘targets’ in rapidly presented frames -divide attention between memorization and visual search

  17. Schneider & Shiffrin (1977): becomes automatic • AUTOMATIC: • happens without intention • few cognitive resources needed

  18. Schneider & Shiffrin (1977): -automatic processing not possible for difficult tasks -both target & distractor are letters -never becomes automatic, remains controlled processing -everyday examples of divided attention?

  19. DRIVING AND INATTENTION 80% of crashes caused by as little as 3 sec inattention 22% of crashes due to cell phone usage

  20. Strayer & Johnston (2001): driving simulation study

  21. 11am

  22. VISUAL ATTENTION Eye movements: windows into the mind saccades (rapid movements) fixations (short pauses; 3/sec)

  23. Eye tracker (noninvasive)

  24. Where do we look? • Areas of high STIMULUS SALIENCE (bottom-up process) SALIENCY MAP (Parkhurst, Law & Niebur, 2003) SCENE SCHEMA: “office schema”  top-down process

  25. ATTENTION DURING ACTIONS Task goals guide fixations to land on objects relevant to the task ORDER of eye movements not the same for everybody

  26. Attending without looking: Inattentional blindness: looking, but not seeing (Mack & Rock,1998) Triangle not recognized

  27. PRECUING: attending to a location without moving the eyes (Posner, Snyder & Davidson, 1980) Reaction time: predicted location < unexpected location

  28. Fix Periphery PHYSIOLOGICAL EVIDENCE FOR PRECUING (Colby, Duhamel & Goldberg, 1995) • Light at fixation point and in the periphery • Trained to always look at the fixation point • “Fixation only” condition: release handle when fixation light dimmed • “Fixation and attention” condition: release handle when peripheral light dims Record from neuron that fires for peripheral light

  29. FIX PERIPHERY

  30. OCCLUSION OBJECT-BASED ATTENTION AC=AB RTB<RTC • RTA < RTB < RTC

  31. Location-based static scene, moving spotlight Attention is independent of objects moving scene, moving spotlight Attention is connected to object

  32. CAN EYE MOVEMENTS DIAGNOSE ATTENTION DISORDER? (Klin, Jones, Schultz & Volkmar, 2003) Autistic viewers Typically developing viewers

  33. Autistic viewers Typically developing viewers

  34. 1pm

  35. The man with a 30 second memory: http://www.youtube.com/watch?v=wDNDRDJy-vo&feature=related -can not form new memories 1-2 minute “bubble” Boundaries: Knowledge vs. memory? Definition: retain, retrieve, and use information about stimuli and skills after the original information is no longer present. Atkinson & Shiffrin (1968) msec-sec 15-30sec years

  36. Sensory Memory -brief retention of the effects of sensory stimulation. The Sparkler’s Trail (persistence of vision)

  37. How much information can be stored in sensory memory? (Sperling, 1960) 50ms presentation 4–5 letters remembered

  38. TWO OPTIONS: • too short time to take in all information • OR • responding takes longer • than decay time rapiddecay…

  39. responding takes longer than decay time high capacity (82%), rapid decay (~1sec)

  40. Functions of Sensory Memory: – Collection of information to be processed – Holding information while processing – Filling in blanks of intermittent stimulation (movies)

  41. 2pm

  42. The Duration of STM Peterson & Peterson (1959): Read 3 letters, followed by a number Count back by 3s Recall 3 letters after 3sec or 18sec – Trial 1: B F T 100 …97 …94 … – Trial 2: Q S D 96 … – Trial 3: K H J 104 … PROACTIVE INTERFERENCE (PI) DECAY

  43. The Capacity of STM (how much information can be stored?) • Digit span: 5-8 ITEMS  5-8 CHUNKS • What’s an item: letter? word? phrase? • Chase & Simon (1973): show chess setup for 5 sec Master knows how to “chunk”, without necessarily having a superior STM

  44. (auditory) The CODING OF INFORMATION in STM (the way information is represented) • AUDITORY CODING (Conrad, 1964): • – saw letters briefly (e.g., FHSGZ…) • asked to write down letters in the order they were presented • when errors occur, they are based on similar sound (F seen as S or X), rather than visual similarity (F seen as E). Sound > Vision

  45. The CODING OF INFORMATION in STM VISUAL CODING (Zhang & Simon, 1985):

  46. The CODING OF INFORMATION in STM SEMANTIC CODING (Wickens, 1976):

  47. 3pm

  48. Complexity: STM as many distinct mechanisms. Demonstration: Reading text and remembering numbers. Baddeley (2000): Working Memory STM: passive simple storage Manipulate info during complex cognition