2. Lexical Access: Generation & Selection

3. Today’s Main Topic Listeners as active participants in comprehension process Model system: word recognition

4. Outline 1.Speed & Robustness of Lexical Access 2.Active Search 3.Evidence for Stages of Lexical Access 4.Autonomy & Interaction

5. Outline 1.Speed & Robustness of Lexical Access 2.Active Search 3.Evidence for Stages of Lexical Access 4.Autonomy & Interaction

6. How do we recognize words?

7. The mental lexicon sport figure sing door carry turf turtle gold turk turkey turn water turbo turquoise turnip turmoil

8. How do we recognize words? The Simplest Theory –Take a string of letters/phonemes/syllables, match to word in the mental lexicon –(That’s roughly how word processors work) …is it plausible?

9. Word Recognition is Fast Intuitively immediate - words are recognized before end of word is reached Speech shadowing at very brief time-lags, ~250ms (Marslen-Wilson 1973, 1975)

10. Lexical Access is Robust Succeeds in connected speech Succeeds in fast speech Survives masking effects of morphological affixation and phonological processes Deleted or substituted segments Speech embedded in noise

11. But… Speed and robustness depends on words in context sentence --> word context effects In isolation, word recognition is slower and a good deal more fragile, susceptible to error …but still does not require perfect matching

12. Questions How does lexical access proceed out of context? Why is lexical access fast and robust in context? When does context affect lexical access? –does it affect early generation (lookup) processes? –does it affect later selection processes?

13. Additional Context Effects Word context affects phoneme identification… word --> phoneme context effects

14. Phoneme Restoration The _eel had a broken axle The _eel on the orange was hard to cut (Warren 1970) Phoneme restoration effects are stronger (i) in words than non-words (ii) later in words (iii) in strongly biasing contexts

15. Phoneme Monitoring press the button as soon as you hear a ‘b’ “in the yard was a large group of twittering birds” “cat, dog, horse, rabbit …” Monitoring is facilitated by context

16. Perceptual Boundaries

17. DA TA

18. Perceptual Boundaries DASK TASK (Ganong 1980)

19. Perceptual Boundaries DASK TASK (Ganong 1980)

20. Perceptual Boundaries DASH TASH (Ganong 1980)

21. Perceptual Boundaries DASH TASH (Ganong 1980)

22. Classic Experimental Paradigms

23. Accessing the Mental Dictionary

24. Reaction Time Paradigms Lexical Decision Priming

25. Looking for Words List 1 sickle cathartic torrid gregarious oxymoron atrophy List 2 parabola periodontist preternatural pariah persimmon porous

26. Looking for Words List 1 sickle cathartic torrid gregarious oxymoron atrophy List 2 parabola periodontist preternatural pariah persimmon porous Speed of look-up reflects organization of dictionary

27. Looking for Words +

28. DASH

29. Looking for Words +

30. RASK

31. Looking for Words +

32. CURLY

33. Looking for Words +

34. PURCE

35. Looking for Words +

36. WINDOW

37. Looking for Words +

38. DULIP

39. Looking for Words +

40. LURID

42. Looking for Words +

43. PRESSULE

44. Looking for Words +

45. DOCTOR

46. Looking for Words +

47. NURSE

48. Looking for Words Semantically Related Word Pairs doctornurse handfinger speaktalk soundvolume bookvolume

49. Looking for Words In a lexical decision task, responses are faster when a word is preceded by a semantically related word DOCTOR primes NURSE Implies semantic organization of dictionary

50. Outline 1.Speed & Robustness of Lexical Access 2.Active Search 3.Evidence for Stages of Lexical Access 4.Autonomy & Interaction

51. Active Recognition System actively seeks matches to input - does not wait for complete match

52. Cost of Active Search… Many inappropriate words activated Inappropriate choices must be rejected Two Stages of Lexical Access activation vs. competition recognition vs. selection proposal vs. disposal

53. Cohort S song story sparrow saunter slow secret sentry etc.

54. Cohort SP spice spoke spare spin splendid spelling spread etc.

55. Cohort SPI spit spigot spill spiffy spinaker spirit spin etc.

56. Cohort SPIN spin spinach spinster spinaker spindle

57. Cohort SPINA spinach

58. Cohort SPINA spinach word uniqueness point

59. Cohort SPINA spinach spinet spineret

60. Evidence for Cohort Activation KAPITEIN KAPITAAL (Marslen-Wilson, Zwitserlood)

61. Evidence for Cohort Activation KAPITEIN KAPITAAL KAPIT… (Marslen-Wilson, Zwitserlood)

62. Evidence for Cohort Activation KAPITEIN KAPITAAL KAPIT… BOOT GELD (Marslen-Wilson, Zwitserlood)

63. Evidence for Cohort Activation KAPITEIN KAPITAAL KAPIT… BOOT GELD (Marslen-Wilson, Zwitserlood)

64. Evidence for Cohort Activation KAPITEIN KAPITAAL KAPIT… BOOT GELD KAPITEIN BOOT GELD (Marslen-Wilson, Zwitserlood)

65. Cohort Model Partial words display priming properties of multiple completions: motivates multiple, continuous access Marslen-Wilson’s claims –Activation of candidates is autonomous, based on cohort only –Selection is non-autonomous, can use contextual info. How to capture facilitatory effect of context…

66. Gating Measures Presentation of successive parts of words –S –SP –SPI –SPIN –SPINA… Average recognition times –Out of context: 300-350ms –In context: 200ms (Grosjean 1980, etc.)

67. Word Monitoring Listening to sentences - monitoring for specific words –Mean RT ~240ms –Identification estimate ~200ms Listening to same words in isolation –Identification estimate ~300ms (Brown, Marslen-Wilson, & Tyler)

68. Cross-Modal Priming

69. The guests drank vodka, sherry and port at the reception (Swinney 1979, Seidenberg et al. 1979)

70. Cross-Modal Priming The guests drank vodka, sherry and port at the reception WINE SHIP (Swinney 1979, Seidenberg et al. 1979)

71. Cross-Modal Priming The guests drank vodka, sherry and port at the reception WINE SHIP (Swinney 1979, Seidenberg et al. 1979)

72. Cross-Modal Priming The guests drank vodka, sherry and port at the reception WINE SHIP (Swinney 1979, Seidenberg et al. 1979)

73. Cross-Modal Priming The guests drank vodka, sherry and port at the reception WINE SHIP (Swinney 1979, Seidenberg et al. 1979)

74. Cross-modal Priming Early: multiple access Late: single access …i.e., delayed effect of context

75. CMLP - Qualifications Multiple access observed –when both meanings have roughly even frequency –when context favors the lower frequency meaning Selective access observed –when strongly dominant meaning is favored by context (see Simspon 1994 for review)

76. Why multiple/selective access? How could context prevent a non-supported meaning from being accessed at all? (Note: this is different from the question of how the unsupported meaning is suppressed once activated) Possible answer: selective access can only occur in situations where context is so strong that it pre-activates the target word/meaning

77. Cohort Model Partial words display priming properties of multiple completions: motivates multiple, continuous access Marslen-Wilson’s claims –Activation of candidates is autonomous, based on cohort only –Selection is non-autonomous, can use contextual info. How to capture facilitatory effect of context…

78. Cohort SPINA spinach

79. Cohort SPIN spin spinach spinster spinaker spindle

80. Speed of Integration If context can only be used to choose among candidates generated by cohort… –context can choose among candidates prior to uniqueness point –but selection must be really quick, in order to confer an advantage over bottom-up information

81. Summary of cohort story Single/multiple access (Simpson) –Context & dominant/subordinate frequency (Rayner & Frazier) –Types of context (Tabossi) Electrophysiological Evidence –M350, distinguishing access from selection/competition –Suggestions about N1, etc. Eye-tracking –continuous activation - TRACE –frequency - Dahan et al. Priority for category or morphological information, decomposition –Vannest & Boland

82. Refining the Story Frequency in context –eye-tracking in reading –eye-tracking and object recognition Electrophysiological measures of multiple access When can context affect generation? –strongly supporting contexts –ERP evidence

83. Evidence for Cohort Activation CAPTAIN CAPTIVE CAPT… SHIP GUARD CAPTAIN SHIP GUARD (Marslen-Wilson, Zwitserlood)

84. Frequency in Reading Rayner & Frazier (1989): Eye-tracking in reading –measuring fixation durations in fluent reading –ambiguous words read more slowly than unambiguous, when frequencies are balanced, and context is unbiased –unbalanced words: reading profile like unambiguous words –when prior context biases one meaning dominant-biased: no slowdown due to ambiguity subordinate-biased: slowdown due to ambiguity contextual bias can offset the effect of frequency bias –how can context boost the accessibility of a subordinate meaning?

85. Frequency in Object Recognition X bench bed bell lobster “Pick up the be..” (Dahan, Magnuson, & Tanenhaus, 2001)

86. Frequency in Object Recognition Timing estimates –Saccadic eye-movements take 150-180ms to program –Word recognition times estimated as eye-movement times minus ~200ms

87. Frequency in Object Recognition (Dahan, Magnuson, & Tanenhaus, 2001)

88. Frequency in Object Recognition (Dahan, Magnuson, & Tanenhaus, 2001)

89. Frequency in Object Recognition (Dahan, Magnuson, & Tanenhaus, 2001)

90. Evidence for Cohort Activation CAPTAIN CAPTIVE CAPT… SHIP GUARD CAPTAIN SHIP GUARD (Marslen-Wilson, Zwitserlood)

91. Matches to other parts of words Word-ending matches don’t prime –honing[honey]bij[bee] woning[apartment] foning[--]

92. Disagreements –Continuous activation, not limited to cohort, as in TRACE model (McClelland & Elman, 1986) –Predicts activation of non-cohort members, e.g. shigarette, bleasant

93. Non-Cohort Competitors (Allopenna, Magnuson, & Tanenhaus, 1998) “Pick up the…” beaker beetle (onset) speaker (non-onset) carriage (distractor)

94. Non-Cohort Competitors (Allopenna, Magnuson, & Tanenhaus, 1998) “Pick up the…” beaker beetle (onset) speaker (non-onset) carriage (distractor)

95. Outline 1.Speed & Robustness of Lexical Access 2.Active Search 3.Evidence for Stages of Lexical Access 4.Autonomy & Interaction

96. M350 (based on research by Alec Marantz, Liina Pylkkänen, Martin Hackl & others)

97. Lexical access involves 1.Activation of lexical representations including activation of representations matching the input, and lateral inhibition between activated representations 2.Followed by selection or decision involving competition among activated representations that are similar in form

98. The mental lexicon sport figure sing door carry turf turtle gold turk turkey turn water turbo turquoise turnip turmoil

99. The mental lexicon sport figure sing door carry turf turtle gold turk turkey turn water turbo turquoise turnip turmoil TURN

100. Automatic activation TURN sport figure sing door carry turf turtle gold turk turkey water turn turbo turquoise turnip turmoil

101. Lateral inhibition TURN sport figure sing door carry turf turtle gold turk turkey water turn turbo turquoise turnip turmoil

102. What is lexical access? time level of activation resting level TURN Stimulus: TURN TURNIP TURF TURTLE Activation Competition Selection/Recognition (e.g. Luce et al. 1990, Norris 1994)

103. RESPONSE TO A VISUAL WORD Sagittal view AP M350 0200300400 Time [msec]

104. MEG response components elicited by visually presented words in the lexical decision task RMS analysis of component field patterns.

107. Neighbors & Competitors Phonotactic probability –sound combinations that are likely in English –e.g. ride vs. gush Neighborhood density –number of words with similar sounds –ride, bide, sighed, rile, raid, guide, died, tried, hide, bride, rise, read, road, rhyme, etc. –gush, lush, rush, gut, gull …

108. RT Behavioral evidence for dual effects Same/different task (“low-level”) RTs to nonwords with a high phonotactic probability are speeded up. Lexical decision task (“high-level”) RTs to nonwords with a high phonotactic probability are slowed down! High probability: MIDE YUSH RT MIDE YUSH RT Low probability: High probability: Low probability: Sublexical frequency effect (Vitevich and Luce 1997,1999) Competition effect

109. Stimuli High probabilityLow probability WordBELL, LINEPAGE, DISH NonwordMIDE, PAKEJIZE, YUSH Materials of Vitevich and Luce 1999 converted into orthographic stimuli. Four categories of 70 stimuli: High and low density words frequency matched. (Pylkkänen, Stringfellow, Marantz, Brain and Language, in press)

110. Effect of probability/density (words) n.s. ** * (Pylkkänen, Stringfellow, Marantz, Brain and Language, in press)

111. Effect of probability/density (nonwords) n.s. * ** (Pylkkänen, Stringfellow, Marantz, Brain and Language, in press)

112. M350 = 1st component sensitive to lexical factors but not affected by competition time level of activation resting level TURN TURNIP TURF TURTLE Activation Competition Selection/Recognition M350 Stimulus: TURN

113. Outline 1.Speed & Robustness of Lexical Access 2.Active Search 3.Evidence for Stages of Lexical Access 4.Autonomy & Interaction

114. Autonomy “…a system [is] autonomous by being encapsulated, by not having access to facts that other systems know about” (Fodor 1983) “Autonomy would imply that processing operations at a given level proceed in the same way irrespective of whatever counsel might be deducible from the higher-level considerations” (Boland & Cutler)

115. Model Implied So Far Stage 1: activation based upon cohorts no effect of context at this stage Stage 2: selection affected by context

116. Boland & Cutler The debate over interaction/autonomy in lexical access focuses on the generation (activation) stage There is broad agreement that context affects lexical choices once multiple candidates have been generated

117. Cross-Modal Priming The guests drank vodka, sherry and port at the reception WINE SHIP (Swinney 1979, Seidenberg et al. 1979)

118. Cross-Modal Priming The guests drank vodka, sherry and port at the reception WINE SHIP (Swinney 1979, Seidenberg et al. 1979)

119. Cross-Modal Priming How could context prevent a contextually unsupported meaning from being accessed?

120. Cross-Modal Priming Conflicting results over effect of context on multiple access Tabossi (1998) –The violent hurricane did not damage the ships which were in the port, one of the best equipped along the coast. –Contexts are highly constraining, prime a specific feature of the target meaning.

121. Active Comprehension Distinction between activation and selection applies equally to syntactic comprehension Is active comprehension a fully general property of language understanding?

122. N400  Negative polarity  peaking at around 400 ms  central scalp distribution

123. (Kutas & Federmaier 2000)

124. ‘baseball’ is not at all plausible here, yet it elicits a smaller N400 - why?

126. Input to left hem. visual system must have privileged access to information about predictions.

127. Implications If Kutas & Federmaier’s results are robust, this implies that –lexical priming can cause apparent early context effects –this implies ‘very active search’ –hemispheres are not alike in this regard

128. Conclusion… Word recognition is fast and robust because of use of context Speed/robustness is achieved by –active generation of candidates from incomplete input –selection among candidates, based upon context Activation ˜ autonomous Selection ˜ interactive

129. Next… Syntax –most issues seen here also apply to syntactic processes –generation stage is much more complex, since syntactic processing is more than just a lookup/activation process.