Project Details
Projekt
Cognitive and signal-driven factors in static and dynamic distance perception
Subject Area
Acoustics
Term
since 2020
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 444827755
Auditory distance perception (ADP) is an important part of spatial awareness and of key importance for evaluating and avoiding potential threats. Contrary to vision, audition is not limited to the frontal field of view and to objects in the line of sight, thus providing information in an omnidirectional manner. Despite the ecological importance of ADP, the underlying sensory cues are much more dependent on the source and the acoustic environment than interaural cues underlying our directional localization in the horizontal plane. ADP can be based on level cues, direct-to-reverberant energy ratio, and, to some degree, spectral tilt, all of which require knowledge or assumptions about the source or the acoustic environment. Nevertheless, in daily life, ADP appears reliable.The goal of this project is to gain a better understanding of static and dynamic ADP and their role in spatial awareness and navigation. Considering the uncertainty of the underlying sensory cues, we hypothesize that higher-level cognitive factors will affect ADP in realistic environments, namely, i) familiarity with the acoustic environment based on prior or continued (acoustic) exposure, ii) emotional valance (potential threat) of the source, and iii) visual information about the scene. We further hypothesize that ADP can provide important cues for navigation, supporting a sensory-independent representation of space.We employ state-of-the-art virtual reality (VR) techniques using a computer game engine for the visual rendering connected with our own specifically adapted and optimized (room) acoustics simulation. In addition to psychoacoustic measurements, we identify related brain areas with functional magnetic resonance imaging (MRI). To enable VR-based research within the technical constraints of the MRI machine, we will develop a modular virtual scenario incorporating posture and limited acoustic cues in the scanner as well as plausible control of acoustic environment, emotional valence of the source, and availability of visual information.Contributing to the areas of the SPP Audictive, in the field of Auditory cognition, we will investigate the effect and interaction of the three factors, familiarity with the acoustic environment, emotional valance of the source, and visual information for ADP. We will assess how self-motion and ADP interact in a navigation task and investigate neural correlates of distance perception using fMRI. Towards Interactive virtual environments, we will improve our room acoustics simulator, to provide a computationally efficient and perceptually evaluated method to simulate distance and motion in various situations. We will develop two interactive scenarios additionally optimized for applicability in the restrictive environment of the MRI scanner. Regarding Quality evaluation methods, we will directly assess the developed virtual scenarios by psychoacoustic methods and brain imaging in isolation and in comparison to real acoustic stimulation.
DFG Programme
Priority Programmes
