Poster C25, Wednesday, August 21, 2019, 10:45 am – 12:30 pm, Restaurant Hall
Distinct neural mechanisms underlying structure building in different syntactic environments
Isabella Fritz1, Anne Marte Haug Olstad1, Giosuè Baggio1;1Language Acquisition and Language Processing Lab, Department of Language and Literature, Norwegian University of Science and Technology, Trondheim
Structure building operations enable us to combine words into more complex structures. In the current study, we investigated these operations using event-related potentials. We designed an experiment with Norwegian (Bokmål) stimuli where the same sequence of two words can either form part of a noun or verb phrase requiring composition (syntactic and semantic) or where the phrasal/clausal boundary falls between these two words (see examples below). Moreover, we manipulated whether structure building occurs in noun phrases (Adjective-Noun) or verb phrases (Verb-Noun), to determine whether the neural signatures are similar or different across different syntactic environments. Examples: Adjective-Noun combination Cut condition: Noen bukser er blå] [jakker kan være svarte. (Literal translation: Some trousers are blue] [jackets can be black.), Adjective-Noun combination Compose condition: Svarte bukser og [blå jakker] kan brukes sammen. (Literal translation: Black trousers and [blue jackets] can be used together.), Verb-Noun combination Cut condition: Musikk er ofte det du trenger] [barna kan slappe av med det. (Literal translation: Music is often what you need] [the children can relax with it.), Verb-Noun Combination Compose condition: Musikk er morsomt men da [trenger barna] mye trening for å lykkes. (Literal translation: Music is fun but then [need the children] much training to succeed.). ERPs were time-locked to the target nouns (jakker/barna), up to which the sentences were syntactically unambiguous: composition was either required (Compose condition) or a new phrase/clause had to be introduced (Cut condition). We then compared the ERPs of the Cut and Compose conditions in both syntactic environments (Adjective-Noun and Verb-Noun). For the Adjective-Noun combinations, we found an N400 effect with a more negative deflection in the Cut Condition and strongest over centro-parietal sites. For the Verb-Noun combinations, we found a more negative deflection in the Compose condition starting at around 200 msec post-noun onset and peaking at around 300 msec. The effect is strongest over anterior-left recording sites. The temporal and spatial profiles of this effect are compatible with a left anterior negativity (LAN). In contrary to previous M/EEG and neuroimaging work, these distinct ERP signatures entail different composition processes depending on the syntactic environment the target noun is embedded in. Studies so far have focused on the comparison between structure building vs word lists, often assuming that structure binding operations are the same across syntactic environments. The current study provides insights into how structure binding processes across syntactic environments translate to different ERP components.
Themes: Meaning: Combinatorial Semantics, Syntax
Method: Electrophysiology (MEG/EEG/ECOG)