Selective deployment of attention to time and modality and its impact upon behavior and brain oscillations

TitleSelective deployment of attention to time and modality and its impact upon behavior and brain oscillations
Publication TypeThesis
Year of Publication2016
AuthorsMühlberg S, Soto-Faraco S
Academic DepartmentDepartment of Experimental and Health Sciences
Number of Pages242
Date Published07/2016
UniversityPompeu Fabra
Thesis TypePhD
KeywordsAttention, Behavior, Cross-modal, Oscillations, Time
Abstract

This thesis investigates the relationship between attention to time and modality at the levels of behavior and pre-stimulus brain oscillations, measured with EEG. Participants were presented with target stimuli from one of two possible modalities, which could appear at one of two different time points. The factors time and modality were interlaced with each other by the fact that each of the modalities was more likely to appear at a different point in time and additionally one of the modalities being more likely overall. We observed that attention to each modality followed its respective temporal likelihood, independently which combination of modalities was used, suggesting a general mechanism for cross-modal temporal decoupling in time. This result is in contrast with cross-modal attention in space, which occurs in a coupled way. At the physiological level, the decoupling effect in time also seems to modulate ongoing neural oscillations in different frequency bands. Based on the results obtained in the time-frequency analysis, we put forward the following tentative hypotheses: alpha oscillations appear to encode switches in modality expectation over sensory cortices, while the beta band might encode the expected modality of the next upcoming stimulus and for the effect of temporal attention itself.

URLhttp://www.tdx.cat/handle/10803/392142