The influence of spatial uncertainty on impulsivity and anticipation

Details

Supervisors

Missal, Marcus

Degree label

Master [120] en sciences biomédicales, à finalité approfondie

Abstract

Uncertainty is present in different forms in everyday life. Our decisions about specific movements are based on prediction or expectation, and we adapt our response for every case. Uncertainty can be applied to different domains such as space or time. Spatial uncertainty is present when an anticipated object of interest has different likely locations, and an observer does not know where it is going to occur. The first aim of this project is to test how spatial uncertainty affects anticipatory saccades. Saccadic amplitude, reaction time and maximum velocity will be measured during an oculomotor task. To analyze saccadic eye movements under levels of spatial uncertainty, the foreperiod paradigm was used. This paradigm contains two stimuli: a warning stimulus (WS) preceding the imperative stimulus (IS) and the time interval between them is called the foreperiod (FP). Saccades are considered as anticipatory when they occur before the appearance of the IS during the FP and are guided by the prediction about the IS appearance. The second aim of this experiment is to find the link between objective oculomotor and subjective questionnaire-based measures of impulsivity. Knowing that there is a link between impulsivity and anticipation, parameters of anticipatory saccades will be correlated with the results of standardized self-administered questionnaires describing levels of impulsivity, anxiety, and intolerance of uncertainty. The first part of the Results section suggests that spatial uncertainty influences task performance measured by saccadic reaction time and amplitude. Furthermore, the length of the total time given for the decision also affects the oculomotor’s performance. The second part of the Results section suggests that parameters of the anticipatory behavior do not correlate with the level of impulsivity, anxiety and uncertainty intolerance of participants. Results obtained in this project neither confirm nor deny the existing theories about the origin of impulsive behavior in uncertainty-related tasks. It cannot be strongly stated if the impulsivity is due to a lack of premeditation or due to a state of increased arousal. In conclusion, results obtained in the current research broaden the knowledge about the link between surprise and anticipation. However, the relationship between impulsivity and anticipation is still unclear and requires further investigation.