Many complex decisions require integrating and assessing multiple streams of dynamic information whilst determining how to act. This dynamic information often contains rhythmic structures which our sensory systems can adapt to and use to anticipate future events. Despite the close relationship between rhythmic temporal expectations and complex decision making being self evident, no experiments explicitly attempt to understand this interdependence. If the theories that have emerged from both domains are to generalise to complex interactive behaviour, the effects of dynamic context on complex decisions must be considered. I argue that timing research must move beyond simple decisions and develop a new experimental framework for addressing the problem. This includes increasing the complexity of experimental tasks, testing the effects of timing on perceptual averaging and subjective value decisions, incorporating timing as an inherent dimension of targets, testing degrees of aperiodicity and exploring the effects that prior knowledge about the temporal structure of a stimulus has on choice. Seven behavioural experiments are reported that implement the new experimental framework. Five use a complex auditory-spatial averaging task to examine effects of periodicity, expectation, prior knowledge and related parameters such as IOI variance. One tests the effects of rhythmic variability and stimulus duration on auditory detection to determine specificity to complex decision making, and one investigates the effects of timing on audio-visual subjective value decisions. The results show that existing theories of temporal expectation do not necessarily generalise to complex decision making. Periodicity reduces the amount of information that is needed to form complex decisions. However, the effects of periodicity (or degree of aperiodicity) on choice are dependent on a number of factors associated with prior knowledge, stimulus rate, variance, decision type and task complexity. Using these findings I develop an explanatory framework called "dynamic inhibition and boosting" that better accounts for behavioural data in the literature compared with existing theories. This explanation is supported by the novel proposal that temporal expectations influence confidence and perceived risk.

L'objectif de cette thèse était d'étudier la modalité auditive dans le syndrome de négligence spatiale unilatérale (NSU) que ce soit dans l'évaluation ou dans la prise en charge. Notre première hypothèse défendue était que, bien que la NSU touche aussi la modalité auditive, des différences dues aux spécificités de chaque modalité existent entre les symptômes auditifs et visuels de ce syndrome neuropsychologique. En conséquence, notre seconde hypothèse était que les spécificités propres à la modalité auditive pourraient permettre de pallier les déficits attentionnels rencontrés en modalité visuelle et, donc, faire de cette modalité un support efficace pour la rééducation. Concernant l'évaluation des symptômes auditifs, les mécanismes d'orientation de l'attention en modalité auditive ainsi que la latéralisation de sons ont été explorés chez des patients atteints de NSU. Ces études ont souligné des difficultés dans les deux domaines dans la NSU. Concernant la réhabilitation, la place de l'audition, et plus particulièrement de la musique, dans les rééducations proposées aux patients atteints de NSU a été explorée. Enfin, un programme de rééducation basé sur la pratique musicale a été créé et testé auprès d'une patiente atteinte de NSU chronique. Celui-ci a montré des bénéfices à long-terme sur les signes visuels de la NSU mais également dans la vie quotidienne. Les résultats de ces études vont dans le sens des hypothèses et soulignent l'importance de prendre en compte la modalité auditive dans la pratique clinique que ce soit lors de l'évaluation du syndrome de NSU ou lors de sa réhabilitation. / The aim of this thesis was to focus on hearing in the evaluation and the rehabilitation of unilateral spatial neglect (USN) syndrome. USN not only affects the visual, but also the auditory modality. The first hypothesis of this thesis was that, due to the specificities of each modality, differences exist between the auditory and visual symptoms of USN. Consequently, the second hypothesis was that the specificities of the auditory modality could permit to compensate the attentional deficits that occur in the visual modality and, thus, make this modality an efficient tool for the rehabilitation. Concerning the evaluation of the auditory symptoms, orienting attention mechanisms in the auditory modality as well as sound lateralisation were explored with patients with USN. These studies showed patients with USN to have difficulties in both. Concerning the rehabilitation, the place of hearing, and in particular of music, in the re-educations in patients with USN was explored. Finally, a program based on music practice was developed and tested with a patient with a chronic USN. This patient showed long-term benefits on USN visual signs and also on daily activities. The results of these studies are consistent with the hypotheses and underline the importance of considering hearing in clinical practice either for the USN evaluation or for its rehabilitation.