| This thesis examines the role of the right hemisphere (RH) in verbal communication. It is postulated that the RH contribution to verbal communication is probably a general contribution at the cognitive resources level rater than a solely specific contribution. In other words, it is claimed that the verbal communication deficits of subjects with RH damaged (RHD) are due to an insufficient amount or poor allocation of cognitive resources.; Chapter one comprises an overview of historical and contemporary views of the RH's role in verbal communication, as well as the theoretical elements justifying the empirical studies reported on this thesis. In Chapter VI, the role of the RH in verbal communication is discussed in the light of cognitive resource theories.; The articles 1a and 1b of the thesis, presented in Chapter II, demonstrate that in a resource competition paradigm, individuals develop different strategies. Even though no patterns in performance were observed during this resources sharing, results suggest that cognitive resources are shared between verbal and non-verbal tasks and that resources allocation varies according to task complexity.; The second and third articles of the thesis, presented on Chapter III, present two studies aiming to increase understanding of the effect of task complexity within the cognitive resources theory. One way to study the complexity of a process is to examine performance at differing levels of difficulty. The second article presents a study using divided visual fields that examined the role of the RH during processing of semantic stimuli of differing levels of difficulty. The third article examines the electric activity generated by each hemisphere during the same semantic task. This study of event related potential suggests that the amplitude of the N400 wave could reflect the effort or cognitive resources demanded during a given task.; The fourth article, presented in Chapter IV, discusses an original approach supporting the cognitive resources theory. This study suggests that the communication deficits seen in RHD subjects are caused by problems in the availability or allocation of cognitive resources.; The last article of this thesis, presented in Chapter V, provides a general overview of the concept of cognitive resources and how to evaluate them. This article suggests the possibility that the RH's role in verbal communication is limited to the contribution of the cognitive resources necessary to achieve the most complex tasks. (Abstract shortened by UMI.)... |
