Referential numerosity in quantification expressions. An ERP study on Italian.

• ¹ University of Zurich, Switzerland
• ² University of Padova, Italy
• ³ IRCSS San Camillo Hospital, Italy

Introduction. The values of morphological number usually encode the reference numerosity: a value of singular refers to a numerosity of one, a value of plural to a numerosity different from one. Quantifiers can also encode information about numerosity; usually when a noun is modified by a quantifier, it must accordingly agree with it in Number. Two quantification expressions in Italian allow to observe a mismatch between the Number value marked on a noun and the Number value encoded by a quantifier. Noun phrases with qualche and alcuni refer to a plural numerosity, meaning ‘some’ (Zamparelli, 2007), but whereas nouns congruently agree with alcuni in the plural, they agree with qualche in the singular. Since both conditions are grammatical, this contrast allows to test the mismatch between numerosity encoded by the quantifier and numerosity encoded in morphological Number without exploiting a violation paradigm. Previous studies revealed an increased cognitive effort when the Number value of a noun mismatches with the numerosity encoded by the quantifier or the numerosity represented in the picture (Zanini et al., 2015; Gastaldon et al., 2015). Methods. 30 nouns referring to countable, concrete objects were chosen, and balanced for frequency by means of the it-WaC corpus (Baroni et al., 2009) and orthographic length. For each noun, a phrase with qualche and one with alcuni were created. The length and the frequency of the whole phrase qualche/alcuni + Noun were also controlled. Two pictures were created for each noun: one representing one object, and one representing the same object repeated four times. Each picture was presented twice: once with qualche+NounSG and once with alcuni+NounPL, for a total of four experimental conditions and 120 experimental stimuli. Fillers were added in order to counterbalance each experimental condition; 120 of them involved a semantic mismatch (e.g., a picture representing four apples was paired with the phrase qualche/alcune banane ‘some bananas’). 26 Italian native speakers were tested. Results and discussion. We analyzed ERPs time locked to the presentation of the noun. The mismatch in numerosity between the picture and the noun was associated to a higher LAN amplitude, recorded mostly on left frontal electrodes. In contrast, semantic mismatch elicited a higher N400, recorded on parietal electrodes in the same time window. No difference was found on the second word between the two target conditions qualche and alcuni/e when analyzing the ERP time course after the second stimulus. However, results seem to suggest a higher LAN after the first word in the qualche+NounSG condition as compared to the alcuni+NounPL condition. Overall, these results point to an incremental integration of information about numerosity in sentence comprehension (Urbach & Kutas 2010).