LingLunch | Derya Cokal (QMUL)

The Processing and Production of Referential Expressions in Neurotypical and Clinical Groups

In this talk, I will highlight the results of five experiments to discuss the processing and production of referential expressions in neurotypical and clinical groups.

With neurotypical groups, anaphors (e.g., it, they) and demonstratives (e.g., this, these) are assumed to signal different procedural instructions. With this in mind, we predicted: (1) while the anaphor it would bring a concrete entity into a reader's focus, the demonstrative this would direct the focus to a predicate proposition in a discourse representation, and (2) readers would prefer they when referring to a smaller paired group within the context, but would prefer these when referring to a larger (maximal) grouping. To test these predictions, we conducted two eye-tracking reading and two sentence-completion experiments with native speakers of English. Our results revealed: (a) the processing and use of anaphoric expressions is affected by the interaction between the lexical characteristics of referential forms and different types of referents, (b) the antecedent-grouping preference depends on type of referring expressions, and (c) the demonstrative refers to a more complex referent than that of anaphora.

In addition, I will discuss whether clinical groups (i.e., participants with/without formal thought disorder (+FTD/-FTD) manifest antecedent preferences for referential expressions in language production. To investigate how disturbance of thought may relate to the referential function of language as expressed in the use of noun phrases (NPs) and the complexity of sentence structures, we developed a comic strip description task to elicit language samples from 30 participants with schizophrenia (SZ), 15 with moderate or severe FTD (SZ+FTD), 15 with minimal or no FTD (SZ-FTD), 15 first-degree relatives of people with SZ (FDRs) and 15 neurotypical controls (NC). We predicted anomalies in the normal referential use of noun phrases (NPs) (sub-divided into definite and indefinite NPs) would identify FTD and that FTD would be linked to reduced definite NPs and linguistic complexity. Our results demonstrated FTD can be identified in specific referential errors and grammatical patterns, which may provide new targets for detection, early intervention, and future neurobiological studies.