Visuospatial asymmetries induced by perceptual illusions and attentional load

The aim of this study is the investigation of visuo-spatial asymmetries, with a bias towards the stimuli presented in the right visual space, induced by different cognitive load levels, which are generated during the execution of a dual-task. Numerous examples of asymmetries in the orientation of visuo-spatial attention are well known in the literature. For example, patients with brain injury exhibit a tendency to ignore information in the control space due to acquired attention deficits, a condition known as unilateral spatial neglect. The evidence of the effect of the increase in the cognitive load in healthy subjects are instead sometimes conflicting: in some studies, it is highlighted that with the increase in the cognitive load there is a reduction of the Pseudoneglect or even an increase in the tendency to focus on the visuospatial attention towards the right space (Ciricugno et al., 2021; Naert et al., 2018; Paladini et al., 2020), while in others no effect emerges (Bonato et al. , 2010; Lisi et al., 2015). This could be due to using oversimplified tasks to induce an effective increase in cognitive load. In order to clarify these conflicting results, we thought of creating a complex dual-task to be computed by healthy adults, in the range age 18-40, who performed a primary audiovisual integration task (Sound-Induced Flash Illusion) with a visuo-spatial discrimination task. In the first part of the dissertation, a theoretical framework will be provided, in which the main mechanisms that coordinate spatial processing will be explored. It will then continue with an overview of the Sound-Induced Flash Illusion and its perceptual phenomena (fission and fusion), in which auditory information drives perception of visual processing. In the last part, the experiment will be presented, to verify the hypothesis that the processing of information presented in the left hemispace would be more affected by high load than the information within the right hemispace.