Liina Pylkkänen (NYU) and Alec Marantz (MIT) Morphological families and phonological neighborhoods – who competes when? MEG evidence.

Effect of lexical frequency High frequency words are processed faster than low frequency words. Prediction of decompositional theories of morphology: cumulative root frequency effects. magnet terror Matched for surface frequency - ic –ize –ism Low frequency derivatives - ist –ize -ism High frequency derivatives Same number of derivates

Effect of lexical frequency High frequency words are processed faster than low frequency words. Prediction of decompositional theories of morphology: cumulative root frequency effects. magnet terror Matched for surface frequency - ic –ize –ism Low frequency derivatives - ist –ize -ism High frequency derivatives Same number of derivates Should be faster due to high cumulative root frequency

Cumulative root frequency effects for inflection Response times to a noun depend on the cumulative frequency of the singular and plural (Schreuder & Baayen, JML, 1997) CAT CATS

But NO cumulative root frequency effects for derivation Family frequency magnet terror - ic –ize –ism - ist –ize -ism HIGH LOW Family frequency does not affect lexical decision times. Family size acid diary - ic –ity –ify –head –test –washed - ist HIGH LOW High family size speeds up lexical decision times. Schreuder & Baayen (1997): S&B: this is a late post-lexical effect. S&B: Therefore, no decomposition in derivation.

Alternative explanation for lack of cumulative root frequency effects in derivation root activationHigh morphological family frequency speeds up root activationBUT competition this facilitation is cancelled out by subsequent competition between the highly frequent morphological family members. Hypothesized affix-competition in priming (Marslen-Wilson, et al. 1994) : In crossmodal priming, NO PRIMING FOR government – governor ALTHOUGH ROBUST PRIMING FOR government – govern (Marslen-Wilson, W. D., Tyler, L., Waksler, R., & Older, L. (1994). Morphology and meaning in the English mental lexicon. Psychological Review 101, 3-33.)

Alternative explanation for lack of cumulative root frequency effects in derivation root activationHigh morphological family frequency speeds up root activationBUT competition this facilitation is cancelled out by subsequent competition between the highly frequent morphological family members.  How to measure timing of root activation, prior to any effect of competition?  M350, an magnetoencephalographic (MEG) response component elicited by word stimuli, peaking at ~350ms post word-onset

Magnetoencephalography (MEG) Measures magnetic fields generated by large populations of neurons firing in synchrony. Millisecond temporal resolution. Millimeter spatial resolution (at least for cortical sources).

Magnetoencephalography (MEG)

What happens in the brain when we read words? [msec] [fT] ms (M170) ms (M250) ms (M350) ms Pylkkänen and Marantz, Trends in Cognitive Sciences, in press. Letter string processing (Tarkiainen et al. 1999) Lexical activation (Pylkkänen et al. 2002)

What happens in the brain when we read words? ms (M350) Lexical activation (Pylkkänen et al. 2002) The M350 is sensitive to 1.Lexical frequency(a) 2.Repetition (b) 3.Phonological similarity (c) 4.Semantic similarity (d) 5.Sublexical frequency (e, f) The M350 is NOT sensitive to 1.Interlexical competition (e) (a)Embick, D., Hackl, M., Schaeffer, J., Kelepir, M. & Marantz, A. (2001). A magnetoencephalographic component whose latency reflects lexical frequency. Cognitive Brain Research 10:3, (b)Pylkkänen, L., Stringfellow, A., Flagg, E., Marantz, A. (2001). A Neural Response Sensitive to Repetition and Phonotactic Probability: MEG Investigations of Lexical Access. Proceedings of Biomag th International Conference on Biomagnetism. Helsinki University of Technology, Espoo, Finland (c)Pylkkänen, L., Stringfellow, A. Marantz, A Inhibition and Competition in Word Recognition: MEG Evidence. Submitted. (d)Pylkkänen, L. Stringfellow, A., Gonnerman, L., Marantz, A Magnetoencephalographic indices of identity and similarity in lexical access. In preparation. (e)Pylkkänen, L., Stringfellow, A. Marantz, A Neuromagnetic evidence for the timing of lexical activation: an MEG component sensitive to phonotactic probability but not to neighborhood density. Brain and Language 81, (f) Stockall, L. Stringfellow, A. Marantz, A The precise time course of lexical activation: MEG measurements of the effects of frequency, probability and density in lexical decision, Submitted. Pylkkänen and Marantz, Trends in Cognitive Sciences, in press.

What happens in the brain when we read words? ms (M350) Lexical activation (Pylkkänen et al. 2002) The M350 is sensitive to 1.Lexical frequency(a) 2.Repetition (b) 3.Phonological similarity (c) 4.Semantic similarity (d) 5.Sublexical frequency (e, f) The M350 is NOT sensitive to 1.Interlexical competition (e) (a)Embick, D., Hackl, M., Schaeffer, J., Kelepir, M. & Marantz, A. (2001). A magnetoencephalographic component whose latency reflects lexical frequency. Cognitive Brain Research 10:3, (b)Pylkkänen, L., Stringfellow, A., Flagg, E., Marantz, A. (2001). A Neural Response Sensitive to Repetition and Phonotactic Probability: MEG Investigations of Lexical Access. Proceedings of Biomag th International Conference on Biomagnetism. Helsinki University of Technology, Espoo, Finland (c)Pylkkänen, L., Stringfellow, A. Marantz, A Inhibition and Competition in Word Recognition: MEG Evidence. Submitted. (d)Pylkkänen, L. Stringfellow, A., Gonnerman, L., Marantz, A Magnetoencephalographic indices of identity and similarity in lexical access. In preparation. (e)Pylkkänen, L., Stringfellow, A. Marantz, A Neuromagnetic evidence for the timing of lexical activation: an MEG component sensitive to phonotactic probability but not to neighborhood density. Brain and Language 81, (f) Stockall, L. Stringfellow, A. Marantz, A The precise time course of lexical activation: MEG measurements of the effects of frequency, probability and density in lexical decision, Submitted. Pylkkänen and Marantz, Trends in Cognitive Sciences, in press.

Phonotactic probability/density: early facilitation RT Same/different task (“low-level”) RTs to nonwords with a high phonotactic probability are speeded up. High probability: MIDE RT YUSH Low probability: Sublexical frequency effect (Vitevich and Luce 1998, 1999)

RT Lexical decision (“high-level”) RTs to nonwords with a high phonotactic probability are slowed down. High probability: MIDE YUSH RT Low probability: mile mild might migrate mike mime mine mire mind mite migraine micro neighborhood activated yuppie yucca yuck yum neighborhood activated Competition effect (Vitevich and Luce 1998, 1999) Phonotactic probability/density: later inhibition

time level of activation resting level Stimulus: TURN TURN TURNIP TURF TURTLEActivation Selection Competition Facilitates activation slows down selection induces intense competition High phonotactic probability/density

time level of activation resting level Stimulus: TURN TURN TURNIP TURF TURTLEActivation Selection Competition Then high probability/ density should delay M350 latencies If M350 = Selection

time level of activation resting level Stimulus: TURN TURN TURNIP TURF TURTLEActivation Selection Competition If M350 = Activation Then high probability/ density should speed up M350 latencies

High probabilityLow probability WordBELL, LINEPAGE, DISH NonwordMIDE, PAKEJIZE, YUSH Four categories of 70 stimuli: Lexical decision. (Pylkkänen, Stringfellow, Marantz, Brain and Language, 2002) Materials (visual)

High probability word Effect of probability/density (single subject) RT M170 M250M350 “M350-2”

Low probability word High probability word Effect of probability/density (single subject) M170 M250M350“M350-2” RT RT

n.s. * * * * (Pylkkänen, Stringfellow, Marantz, Brain and Language, 2002) Effect of probability/density (n=10)

(i) 1 st component sensitive to lexical factors (such as lexical frequency) (ii) not affected by competition time level of activation resting level Stimulus: TURN TURN TURNIP TURF TURTLEActivationSelection Competition M350

(Pylkkänen, Stringfellow, Marantz, Brain and Language, 2002) Earlier effect of probability/density on M250 amplitude (n=10) *

Effect of high phonotactic probability/ high neighborhood density: Hypothesis M350 RT - speed-up due to sublexical frequency - slow-down due to competition Effect of high morphological family frequency?M350 RT - speed-up due to cumulative root frequency - slow-down due to competition from highly frequent family members

Contrast 1: Family frequency Contrast 2: Family size Four categories of visual words, all nouns magnet (n=18) terror (n=18) - ic –ize –ism - ist –ize -ism HIGH LOW Matched for: Length Freq. of the sg, Cumulative freq. of the sg. & pl. forms Family size Mean bigram frequency acid (n=21) diary (n=21) - ic –ity –ify –head –test –washed - ist HIGH LOW Matched for: Length Freq. of the sg, Cumulative freq. of the sg. & pl. forms Family frequency (not perfectly) Mean bigram frequency Materials (from Baayen, R. H., Lieber, R., & Schreuder, R. (1997). Linguistics 35, )

Behavior * n.s. * (Pylkkänen, Feintuch, Hopkins & Marantz, Cognition, to appear)

MEG data, single subject (Pylkkänen, Feintuch, Hopkins & Marantz, Cognition, to appear)

MEG data, n = 10 LR AXIAL VIEW AP SAGITTAL VIEW LR CORONAL VIEW = M250 = M350 LATENCYINTENSITY M250 M350 ** P=0.006 n.s. P=0.03 * n.s. (Pylkkänen, Feintuch, Hopkins & Marantz, Cognition, to appear)

MEG data, n = 10 LR AXIAL VIEW AP SAGITTAL VIEW LR CORONAL VIEW = M250 = M350 M350 ** P=0.006 n.s. P=0.03 * n.s. High family size speeds up the M350, just like it does RT early  Family size affects processing early. inhibitoryContrary to the hypothesis from decomposition, high family frequency has an inhibitory effect on M350 amplitudes (Pylkkänen, Feintuch, Hopkins & Marantz, Cognition, to appear)

M170 M250 M350 RT (lexical decision) High sublexical frequency/ neighborhood density  Smaller amplitude  Shorter latency  Longer RT  (competition) High morphological family frequency  Larger amplitude  (competition)  High morphological family size  Shorter latency  Shorter RT  1. Difference in the time course of competition. 2. High family size has an early facilitory effect. Why?

1. Difference in the time course of competition High frequency morphological family TERROR - ist –ize -ism LINE loin fine pine nine light like lie lane lime High density phonological neighborhood (frequency-weighted) LINE loin fine pine nine light like lie lane lime TERROR terrorism terrorize terrorist DECOMPOSITION NO DECOMPOSITION  Relationship between target and competitors qualitatively different: difference is due to morphology.  Difference is due to the different phonological and/or semantic properties of the competitors.

1. Difference in the time course of competition LINE loin fine pine nine light like lie lane lime TERROR terrorism terrorize terrorist NO DECOMPOSITION  Difference is due to the different phonological and/or semantic properties of the competitors. TERRORISM – TERROR.  Non-decompositional account also predicts interference effects in priming for pairs such as TERRORISM – TERROR.  BUT this is completely unsupported by data – effect is robustly facilitory (e.g. a-d). (a) Marslen-Wilson, W. D., Tyler, L., Waksler, R., & Older, L. (1994). Morphology and meaning in the English mental lexicon. Psychological Review 101, (b)Pylkkänen, L. Stringfellow, A., Gonnerman, L., Marantz, A Magnetoencephalographic indices of identity and similarity in lexical access. In preparation. (c)Gonnerman, L. 1999, Morphology and the lexicon: exploring the semantics-phonology interface, PhD thesis, University of Southern California. (d)Rastle, K., Davis, M., Marslen-Wilson, W., & Tyler, L.K. (2000). Morphological and semantic effects in visual word recognition: A time course study. Language and Cognitive Processes, 15, Rastle, K., Davis, M., Marslen-Wilson, W., & Tyler, L.K. (2000). Morphological and semantic effects in visual word recognition: A time course study. Language and Cognitive Processes, 15,

1. Difference in the time course of competition High frequency morphological family TERROR - ist –ize -ism LINE loin fine pine nine light like lie lane lime High density phonological neighborhood (frequency-weighted) DECOMPOSITION  Competition between morphological family members appears to precede competition between phonological neighbors.  There are currently no models capturing this effect but what does seem clear is that an account of the phenomenon needs to make a distinction between morphological and phonological competitors.

2. High family size has an early facilitory effect One possibility: Effect is semantic in nature and is related to effects of polysemy. Heavily polysemous words (such as belt) are processed faster than words that only have few “senses” (such as ant). (Rodd, Gaskell & Marslen-Wilson (2002) Making Sense of Semantic Ambiguity: Semantic Competition in Lexical Access. Journal of Memory and Language 46, 245–266) Different morphological environments induce different senses of the root and therefore nouns with large morphological families have more senses than nouns with small morphological families. Prediction: semantically opaque morphological family members should contribute to the family size effect the most, as those would involve the most “sense-switching”. BUT: there is at least some evidence that the family size effect is in fact mostly carried by the semantically transparent members of the family. (De Jong NH, Feldman LB, Schreuder R, Pastizzo M, Baayen RH (2002) The processing and representation of Dutch and English compounds: peripheral morphological and central orthographic effects. Brain Lang 2002 Apr-Jun;81(1- 3): )

2. High family size has an early facilitory effect Alternatively: The family size effect is not a facilitory effect of high family size, but an inhibitory effect stemming from more potent competitors in the low family size condition. aciddiary -ic -ity -ify -head -test -washed -Ø -st -ø Keeping family frequency constant but lowering family size creates more potent competitors. (See Perea and Rosa (2000) for a review of studies indicating that the important neighborhood variable in visual word recognition is not the number of neighbors per se, but the frequency of a word's neighbors relative to its own frequency. Perea M. and E. Rosa (2000) Psicologica, 21, )

Conclusion Evidence for decomposition (although somewhat indirect). Evidence for the existence of morphological competition (cf. Marslen-Wilson 1994). Identification of a neural correlate of the morphological family size effect. Thanks to: Sophie Feintuch & Emily Hopkins (Portsmouth High School, NH)