Earing-impaired persons and also a normalhearing control group. For bone-conducted sound lateralization, Kaga et al. (2001) [14] identified, making use of a selfrecording apparatus that DL-AP4 References measured ITD and ILD, that the skills had been maintained in lots of individuals with bilateral microtia and aural atresia. Schmerber et al. (2005) [15] obtained time-intensity trading functions working with ITD and ILD inside the similar ear from patients with bilateral congenital aural atresia, and showed that time-intensity trading was present within the individuals. They concluded that a binaural fitting of BCHAs could optimize binaural hearing and strengthen sound lateralization, and recommended systematic bilateral fitting in aural atresia individuals. Further advances in technologies have led for the improvement of several kinds of BCDs apart from conventional BCHAs having a steel-spring headband or with framed glasses. Reinfeldt et al. (2015) [16] categorized these as standard skin-drive BCDs, passive transcutaneous skin-drive BCDs, percutaneous direct-drive BCDs, and active transcutaneous direct-drive BCDs. Lately, a non-surgical adhesive BCD has been produced commercially offered also [17]. Furthermore, cartilage conduction hearing aids (CCHAs) happen to be created by Hosoi et al. (2010) [18], without having the powerful stress on the steel spring as utilised in standard BCHAs or surgical operations for BAHAs.Audiol. Res. 2021,So far, investigation on sound localization therefore has been carried out using the various types of devices talked about above. The majority of the research have reported that bilaterally fitted devices showed far more enhanced sound localization than the unilaterally fitted ones. Because the basis, Zeitooni et al. (2016) [19] investigated the effects of binaural hearing with bilateral BCHAs, measuring the spatial release from masking, the binaural intelligibility level distinction, the binaural masking level distinction, and also the precedence effect in adults with standard hearing. In all tests, the results with bilateral BC stimulation at the BCHA position illustrated an potential to extract binaural cues similar to BC stimulation in the mastoid position. They, nevertheless, didn’t test sound localization, the accuracy of which is usually impacted by a variety of aspects, for instance the kind of device, the participants, and also the experimental process. The present review aimed to discuss the factors affecting sound localization or lateralization, also as their accuracy, for persons with bilateral (simulated) CHL working with bilateral devices. For the initial aim, the factors affecting sound localization and lateralization were classified, and also the relevant investigation is discussed. For the second aim, concerning the accuracy of sound localization and lateralization applying a multi-loudspeaker method, in lieu of a questionnaire such as “The Speech, Spatial and Qualities of Hearing Scale (SSQ) [20], the clinical literature associated to persons with hearing loss or typical hearing was searched on “Google Scholar”. The key phrases for this search have been “bone conduction”, “localization”, “bilateral”, and “conductive hearing loss” for sound localization, and “bone conduction”, “lateralization”, “bilateral”, and “conductive hearing loss” for sound lateralization. The search was performed for literature from 2012 to August 2021 for the reason that Janssen et al. (2012) [12] had currently reviewed the literature from 1977 to 2011. The tactic made use of to pick the literature for the second aim was as follows. Very first, the keyword search situations in “Google Scholar” were set to e.