L’architettura neurocognitiva del linguaggio fra concetti e grammatica. BISMoS: una batteria di test per lo studio dell’interfaccia fra semantica e morfosintassi in italiano

The present volume addresses the question of the neurocognitive basis of the linking mechanisms of conceptual-semantic representations with grammatical categories. The question of how concepts are formed by humans and conveyed through languages dates back many centuries and has long baffled scientists from different disciplines. However, the neurobiological basis of encoding a multifactorial and graded conceptual space with formally discrete and arbitrary language systems is almost entirely unknown and the neurocognitive principles underlying the organization of meaningful linguistic units in complex and coherent morphosyntactic systems still have to be defined. To address this unresolved and crucial question, the Authors proposed a novel approach to study language processing in case of neurological injury. This approach, in which Linguistics and Cognitive Neuropsychology benefit from each other, is based on crosslinguistically valid principles that govern the complex mapping relationships between concepts and grammar and, in particular, between semantics and morphosyntax: BISMoS, in fact, a new Battery of tests to study the Interface between Semantics and MorphoSyntax, has been developed to specifically and systematically investigate the neurocognitive correlates of the interface between these two main dimensions of language. Importantly, BISMoS allows to capture not only a general dissociation between semantics and morphosyntax, on the whole, but also specific dissociations internal to each (macro)dimension and dependent on the processing of distinct types of semantic properties and/or distinct types of morphosyntatic features. A shown in chapter 1, in fact, semantics and morphosyntax do not correspond to homogeneous blocks: certain components of word meaning – which are called interface semantics – are morphosyntactically relevant, while others are not, and certain morohosyntactic features are semantically determined, while others are not. Unlike previous batteries, BISMoS includes specific tests that allow to disentangle principles and mechanisms underlying even subtle distinctions between components and subcomponents of language and to account for them in a unitary model of language processing system. Because of its modular structure (see chapter 1, §5.2), BISMoS is particularly suitable for patients, including those affected by neurodegenerative diseases. Moreover, as able to identify isolable subcomponents of language processing within a coherent model of language system, it provides a refined and powerful tool for the identification of the functional locus of the impairment and, therefore, for establishing significant correspondences between the patients’ performance in different domains and regional brain damage. BISMoS, then, can provide specific contributions to the increase of the diagnostic accuracy in the clinical setting, allowing better discriminations between different patterns of performance (including linguistic and/or cognitive deficits, involving conceptual semantic representations vs. formal grammatical categories) and, therefore, between different diseases. Its use will provide a foundation for the functional recovery of linguistic (and cognitive) abilities by identifying the specific types of deficit that need to be targeted. The first chapter of the present volume explains the rationale of the project and describes the structure (including an accurate account of materials and methods), the objectives and the possible outcomes of BISMoS, also in comparison with previous batteries; moreover, it offers an interesting discussion of the relationship between language and cognition and of the role of the cognitive neuropsychological perspective in the study of language systems. Chapter 2 reports the norming study, conducted on 99 healthy Italian subjects, pooled across homogeneous groups for age, sex and years of education. This chapter provides a detailed description of statistical analyses and results, and clearly shows the quantitative and qualitative evaluation of how the stimuli included in each test category of the battery are processed in physiological conditions. Chapter 3 explains how to use BISMoS in Cognitive Neuropsychology. Moreover, by analyzing different types of language disorders and neurological diseases, it shows how the rationale behind the battery and its structure are functional to the study of language processing in patients with various profiles. It also offers a clear explanation of the criteria for a correct evaluation of the patients’ performance in each task of each test category. The first three chapters of the book provide a fundamental tool to any future research that uses BISMoS to study language processing in patients. Chapter 4, in the end, includes all stimuli, divided per test category and tasks, together with the response protocol and the necessary materials for patient testing and result interpretation (both quantitative and qualitative). In conclusion, the present book offers an innovative tool for the study of language processing in patients, that can shed new light on the neurocognitive architecture of language and on the functional organization of human brain.