Auditory spatial assessment in real and virtual environments: a scoping review of current evidence and future directions

Abstract Background Spatial hearing is typically assessed using free-field loudspeakers, which provide accurate acoustic cues but is impractical for many research and clinical settings. Advances in virtual auditory displays and head-tracked headphone rendering have created opportunities for alternative spatial assessment methods, yet the extent to which virtual presentations reproduce real-world performance remains uncertain. Objective The main objective was to map and synthesize the current evidence comparing auditory spatial assessments conducted with real sound sources and those performed in virtual listening environments, and to identify methodological factors that influence agreement between the two. Method Eligible studies involved human participants and reported at least one spatial outcome, such as azimuth or elevation localization, distance perception, spatial discrimination, bisection thresholds, or electrophysiological responses to spatial change. A comprehensive search was conducted in PubMed, Scopus, and IEEE Xplore for articles published between 1980 and 2025. Additional records were identified through backward citation searching of included studies. All retrieved references were imported into Rayyan for screening and deduplication. Results Eighteen studies met the eligibility criteria. Studies on horizontal localization showed the strongest correspondence between real and virtual conditions, particularly when individualized binaural room impulse responses (BRIRs) or head-related transfer functions (HRTFs) and head tracking were used. Elevation judgments showed the largest discrepancies, with most virtual methods, especially those using generic HRTFs, producing larger errors, vertical compression, and more front-back confusions. Distance perception outcomes were reproduced reasonably well when reverberation cues were modelled accurately. Electrophysiological evidence indicated preserved early auditory responses using real sources, but attenuated or delayed later components for virtual sources. Methodological choices such as filter individualization, room simulation, and the availability of visual cues substantially influenced outcomes. Conclusion Virtual auditory environments can approximate performance on real sound sources under well-controlled conditions, especially in the horizontal plane, but notable limitations persist in elevation identification and fine spectral discrimination. Virtual methods require careful calibration and standardization before they can reliably replace loudspeaker arrays in research and clinical practice.