Curriculum
Neuroscience, Technology, and Society, XXXII series
Grant sponsor
UNIPD
Supervisor

Sara Mondini
Co-supervisor

Ombretta Gaggi

Project: Cognitive reserve in language: how exposure to learning experiences influences language processing and pragmatic communication in healthy aging and in neurodegenerative disorders.
Full text of the dissertation book can be downloaded from: http://paduaresearch.cab.unipd.it/12150/

Abstract: Cognitive Reserve (CR) can be defined as a repository of cognitive abilities and learnings, which increase the complexity of brain networks and in turn become protective for preventing age-related changes and brain pathologies. Since human language is one of the most studied cognitive domains, the effect of CR on language can provide new perspectives on understanding how CR influences cognition. Previous studies have shown that high CR is correlated with language proficiency as measured with vocabulary size or verbal analogy. However, to date, it is not clear whether the effect of CR on language is homogenous across psycholinguistic characteristics. This project mainly aimed at investigating the CR effect on language processes (i.e., lexical access, semantic association and reading processes) and on pragmatic abilities (i.e., the ability to communicate in different contexts, through detecting and manifesting communicative intentions). Furthermore, one of the pragmatic tasks used in this project was transformed from its original paper-and-pencil version into a user-friendly computer application, for a more agile examination of pragmatic skills in clinical contexts.
This project includes five studies. Study 1 involved 65 healthy older adults whose performance was analyzed using a digital tool, which I devised, that combines three language tasks (Lexical Decision, Semantic Matching and Sentence Reading). The aim was checking the effect of CR on performance while varying lexical frequency (high vs. low) and lexical semantics (concrete vs. abstract words), and on reading times of sentences with either syntactic or semantic violations. CR predicted the overall language performance, with stronger effects on low-frequency and abstract words compared to high-frequency and concrete words. CR influenced reading times in both syntactic and semantic violations, but at different points in the time-course of sentence processing. These findings suggest that abstract words and low-frequency words can be well preserved by maintaining an active lifestyle in aging, and that high CR not only implicates higher knowledge of grammar rules but also better monitoring of these rules “on-line” during reading.
Study 2 and Study 3 are strictly connected to each other. Study 2 explored the retrieval of proper names and the sensitivity of this lexical category to the modulatory effect of CR in patients with dementia. Thirty-two elderly patients with dementia were matched to healthy controls. All participants were administered the Montreal Cognitive Assessment (MoCA) to measure their global cognitive performance, a paper-and-pencil Famous Face Naming test to assess proper name retrieval, and the Cognitive Reserve Index (CRI) questionnaire. Findings showed that naming proper names was independent from CR possibly due to their lexical nature, which lies in a poor semantic connection between proper names and their bearers. Study 3 aimed at examining the effect of CR not only on proper names, but also on names with other semantic features (logo names and common nouns). To do this, I used a new digital tool which I developed, suitable for finer analyses of behavioral outcomes. The hypothesis was that CR contributed more in retrieving common nouns and logo names, which are highly semantically interconnected, than retrieving proper names, which are pure referring expressions. Forty-six Italian healthy older adults were tested. The results showed that participants were significantly faster and more accurate in name retrieval when CR was high. As regards accuracy, the effect of CR was lower for proper names than for common nouns and logo names, which did not differ from each other. These findings suggest that high CR may help context-driven information processing. Availability of context information seemed therefore a very interesting topic to explore in association with the possible effects of CR.
A crucial component for the efficient use of language is the “context” where a message occurs, which directly falls into the pragmatic domain. Different neurological diseases can affect the ‘pragmatic system’ at different levels, interfering with ability to communicate in varying contexts and with different interlocutors, but, to my knowledge, no study to date has investigated the pragmatic profile of patients with Parkinson’s Disease (PD) and how CR can relate to this profile. This was the issue of Study 4, which showed that CR measures were highly associated with pragmatic comprehension abilities and weakly associated with pragmatic production abilities. which were correlated with the severity of patients’ motor deficit.
Assessment of pragmatic abilities is important in clinical contexts. In the traditional neuropsychological assessments, however, pragmatic traits of a patient are typically assessed qualitatively through an informal conversation. Study 5 aimed at developing a user-friendly and agile software application by converting a structured paper-and-pencil task for pragmatic assessment. The task lasts 5 minutes. In the paper-and-pencil traditional form, the examiner has to evaluate twenty-two pragmatic discourse features, trying to simultaneously count their frequency of occurrence. Thus, in its paper-and-pencil form, the administration of this task can be very demanding for the clinician. Study 5 allowed to create a digital Interview task which optimizes time and resources of administration. To my knowledge, this is the first attempt to develop the digital version of a highly professional tool for the evaluation of several dimensions of pragmatic and paralinguistic features of discourse.