Alec Marantz, Olla Somolyak, Ehren Reilly

1. Tracking the able in stable:Toward an understanding of morphological decomposition in processing and representation Alec Marantz, Olla Somolyak, Ehren Reilly Bill Badecker, Asaf Bachrach, Susan Gabrieli, John Gabrieli KIT/NYU MEG Joint Research Lab (et al.) Departments of Psychology and Linguistics NYU

2. Outline • Strawmen Burnt • cartoon dual route model • cartoon obligatory decomposition model • Real Issues Identified • modality specific access “lexicon”? • access lexicon contains morphologically complex forms? • knowledge contributions to affix-stripping/decomposition? • effects of decomposition on stem access? • effects of stages of processing on RT in, e.g., lexical decision?

3. Experiment Done • evidence for, at least, full decomposition or interactive dual route model • no support for whole word access route • support for early effects of surface frequency of affixed forms relative to stem frequency – at decomposition stage • Experiment Planned • tracking the -able in amiable and stable

4. Competing Models of Lexical Access – take your pick(or, the field’s take on Words and Rules)

5. Saturday Morning Models of Lexical Access(as most people read Pinker) • Full storage model: all complex words (walked, taught) stored and accessed as wholes: • only surface frequency effects on access predicted • Full decomposition model: no complex words stored and accessed as wholes: • only stem frequency effects on access predicted

6. Dual Route Model (hooray!): irregular complex forms are stored and accessed as wholes; regular complex forms (except high frequency regulars) are not: • surface frequency effects on access for irregulars and high frequency regulars • stem frequency but no surface frequency effects on access for regulars

7. Facts Support Dual Route Model, if Alternatives are these Cartoon Versions • Fact: Stem Frequency effects in access for complex words • Fact: These effects are arguably not attributable to post-access decomposition • particularly when considered in connection with masked priming studies showing morphological priming when neither form nor semantic priming are found

8. But, fact: Surface frequency effects in lexical access are found in wide variety of cases, including completely regular morphology (e.g., for most inflected words in Finnish)

9. Problems for Cartoon Dual Route Model • The representation of even irregular derived or inflected forms must be complex • from the grammatical point of view, from morphology, syntax and semantics, felt is as complex as walked • e.g., behavior with respect to do support, further inflection, impossibility of derivation, rigidity of meaning… • from the psycho and neurolinguistic point of view, irregulars contain the stem in the same way that regulars do • taught-teach identity priming in long-lag priming and for M350 brain response

10. So, the issue of “whole word” access to complex irregulars must be focused on possible “whole word” representations in something like a modality-specific “access lexicon,” not on the lexical representations of such forms, which must be complex and as complex as the representations of regulars.

11. Comparing surface and base frequency effects: Level 1 vs Level 2 Morphology

12. Surface Frequency Effect:Biggest for “Level 1”

13. Base Frequency Effect:Only for “Level 2”

14. Groups of Affixes

15. Base Frequency Effect:Nothing significant for groups of affixes

16. Surface Frequency Effect

17. Semantic Transparency Doesn’t Explain Lack of Base Frequency Effects

18. Whole Word “Representations” for Regulars • Surface frequency effects on access are seen for a variety of completely regular derivations and inflections. • This should not surprise any obligatory decompositionalist, since surface frequency effects could be tied to the decomposition (the more you’ve decomposed a particular letter/sound sequence into stem and affix, the faster you are at it) or recombination (the more often you’ve put together a particular stems and affix, the faster you are at it) stages of processing. But any such effects imply representation of whole word as complex structure, regardless of regularity.

19. “Representations” • Saying that every combination of morphemes in perception or production, no matter how regular, leaves a trace in the language system of the speaker is saying that frequency information is part of the grammar and that all combinations of morphemes are stored in some sense. • Theories of morphology in particular have made explicit the difference between stored information about combinations of morphemes that may have grammatical effects on syntax, morphology, phonology and certain types of compositional semantics and stored information about combinations that may only have an effect on “idiomatic” or phrasal meanings.

20. It’s fairly straightforward to claim that walked is “stored” as a complex form with a certain frequency in the same way that And now for something completely different is. Both must be composed with the grammar when heard or produced, but both may have frequency and special meaning information associated with them that, as far as the kinds of things most linguists study, have no implications for the grammar whatsoever.

21. Beyond the Cartoons

22. Realistic Full Decomposition Models Must… • Recognize that complex words, both regular and irregular, are stored in some sense, leading to possible surface frequency effects • Investigate the role of surface frequency in • decomposition • stem access • recombination

23. Realistic Dual Route Models Must… • Recognize that all complex forms must be representationally complex, containing structures of morphemes and contrasting with monomorphemic constituents • Focus on the possible existence of stored “whole word” representations at modality-dependent “access lexicons” (whole word word form representations) to distinguish themselves from obligatory decomposition models

24. And now for something completely different Encyclopedia Stored info about encountered items) [un[real]] UN+REAL (??) lemma (lexical entry) “not” REAL modality specific access lexicon(?) unreal un real form code u n r e a l

25. Realistic Interactive Dual Route Models • Discuss possible sources for facilitation or difficulty for identifying the affixes for decomposition • These include phonotactic clues to morpheme boundaries (cf. sixths) as well as statistically properties of the the combinations of morphemes, particularly conditional probabilities.

26. Effect of “Dominance” on Lexical Access • Jen Hay has made some about the importance of the relative frequency of a morphologically complex form with respect to the frequency of its stem. • Complex words with high frequencies relative to their stems are “affix-” or “surface dominant”; those with low frequencies are “stem” or “base dominant” • Hay: affix dominance leads to difficulty in parsing/decomposition, thus reliance on whole-word recognition and suppression of complexity of representation.

27. Simplistic Prediction of Hay Model • Affix dominant words should show surface frequency effects since they are accessed via the whole word route. • Stem dominant words should show stem (cumulative) frequency effects since they are accessed via the decomposition route.

28. mere merely mere merely mere merely mere merely merely sane sanely sane sane sane sane sane sane sane matched for stem frequency (9), difference in surface dominant (mere(ly)) or stem dominant (sane(ly))

29. Taft (2004): “Morphological Decomposition and the Reverse Base Frequency Effect”Makes same predictions as Hay for RT with full parsing theory • Base frequency effects… • RT to complex word correlates with freq of stem • …reflect accessing the stem of morphological complex forms whereas • Surface frequency effects… • RT to complex word correlates with freq of complex word • …reflect the stage of checking the recombination of stem and stripped affix for existence and/or well-formedness.

30. Full Parsing* PL-Dominant PL (High Surface Freq) Latency of Lexical Access Post-Access processing (until response) SG-Dominant PL (Low Surface Freq) Latency of Lexical Access Post-Access processing (until response) How can we distinguish these accounts of RT differences? Full Listing / Parallel Dual Route PL-Dominant PL (High Surface Freq) SG-Dominant PL (Low Surface Freq) Reilly, Badecker & Marantz 2006 (Mental Lexicon)

31. Sequential processing of words

32. Sequential processing of words Pylkkänen and Marantz, 2003, Trends in Cognitive Sciences

33. Repetition Frequency (Embick, Hackl, Shaeffer, Kelepir, Marantz, Cognitive Brain Research, 2001) (Pylkkänen, Stringfellow, Flagg, Marantz, Biomag2000 Proceedings, 2000) Latency of M350 sensitive to lexical factors such as lexical frequency and repetition

34. Experiment: parallel behavioral and MEG processing measures • Lexical Manipulation (Baayen, Dijkstra & Schreuder, 1997, JML) • Lemma frequency (CELEX database) • Morphological dominance (surface frequency)

35. Stimuli: 3 Lexical Categories • Nouns: singular/plural • bone • bones • Verbs: stem/progressive • chop • chopping • Adjectives: adjective/-ly adverb • clear • clearly

36. Experiment: behavioral measures • Reliable effect of stem frequency in RT

37. Experiment: behavioral measures • Interacting effects on RT of affixation (base vs. affixed) and dominance (base-dominant vs. affix-dominant

38. Analysis of M350 peak latency • Reliable effect of Stem frequency for unaffixed words and for affixed words Unaffixed Words Affixed Words

39. Analysis of M350 peak latency • Reliable effect of Affixation (base vs. affixed)

40. Analysis of M350 peak latency • No effect of Dominance (base-dominant vs. affix-dominant) on M350 peak latency

41. Analysis of M350 peak latency • No interaction between Dominance (base-dominant vs. affix-dominant) and Affixation (base vs. affixed) Cumulative Response Time M350 peak latency

42. Analysis of M350 peak latency • Evidence that early stages of access for affixed words is based on full parsing: Whole word frequency affects post-access stages.

43. Problem with this Conclusion • No acknowledgement of the effects of dominance and/or surface frequency on parsing stage of decomposition • No acknowledgement of possible effects of finding affix on stem access

44. Possible effects of dominance at different stages in word recognition

45. Let’s examine these effects with correlational analysis • [For affixed words, dominance and surface frequency are correlated in these materials, perhaps unfortunately for our purposes]

46. For all words: Stem Frequency r = -0.11; p << 0.01 Surface Frequency r = -0.15; p << 0.01 Word Frequency r = -0.18; p << 0.01 Dominance r = -0.07; p < 0.01 Affixation r = 0.08; p < 0.01 For affixed words only: Stem Frequency r = -0.07; p < 0.05 Surface (word) Frequency r = -0.17; p << 0.01 Dominance r = -0.13; p << 0.01 For affixed surface dominant words: Stem Frequency r = -0.14; p < 0.01 Surface Frequency r = -0.14; p < 0.01 Correlations with RT

47. Correlational Analyses • Within a subject (or two): • for each sensor, for each point in time, correlate measured magnetic field strength for each stimulus with the value of some stimulus variable (length, frequency, etc.)

48. correlation with left vs. right hemifield presentation

49. 150ms

50. RMS Correlations Across Subjects • For some set of sensors, calculate at each time point in each experimental “epoch” the root mean square (RMS) = the square root of the mean of the squares of the values at each sensor (after normalization of values) • So, for each subject, for each item, an RMS “wave” can be provided for the correlational analysis • At each time point, the RMS value for each stimulus is correlated with a stimulus variable