PhD Thesis Dissertation - Utku Kaya

Title: Neural Mechanisms Underlying Sub-Second Crossmodal Time Perception 

PhD Candidate: Utku Kaya

Program: Cognitive Science Department 

Date: 23 January Tuesday 15:30

Place: Conference Hall-01

Abstract: The integration of information from different senses is central to our perception of the world including the fundamental attributes of space and time. Audiovisual interactions have been particularly well studied in this context. Similar to the fact that visual stimuli can drive the perception of where a sound comes from (spatial ventriloquism), auditory stimuli can drive the perceived timing of visual events (temporal ventriloquism). These interactions are in accordance with the auditory system’s superior temporal and the visual system’s superior spatial resolution. The current study aims to understand the neural mechanisms underlying temporal ventriloquism. To achieve this objective, we collected behavioral and electroencephalography (EEG) data in tandem in four experiments. In Experiment-1, we have investigated how a single auditory event changes the perceived timing of a single visual event by varying the temporal offset between auditory and visual events. Experiment-2 focused on the mechanisms underlying the auditory influences on the visual time interval perception. In Experiment-3, we studied the effect of temporal ventriloquism on the perception of apparent motion by altering the timing of visual events leading to the motion percept. In the last experiment, we investigated the cortical mechanisms involved in the time interval adaptation aftereffects on the visual apparent motion. Overall, these experiments have significant contributions to our understanding of auditory influences on visual timing and cross-modal time perception in general. More generally, this study attempts to bridge the gap between our unified multisensory representation of the external world and low-frequency brain oscillations within the context of temporal ventriloquism.