Evaluation of spatial cognition in cochlear implant users

Spatial cognition skills are realized by the integration of all sensory inputs, primarily auditory, visual, and vestibular inputs. Deficiencies in sensory inputs can affect spatial skills. The aim of this study is to evaluate the spatial cognition skills of cochlear implant users with severe and profound hearing loss and to compare the spatial cognition skills of cochlear implant users with and without otolith dysfunction. The study included 19 cochlear implant users with otolith dysfunction, 21 cochlear implant users without otolith dysfunction, and 20 age- and sex-matched healthy participants. The spatial skills of the participants were evaluated with the triangle completion task (TCT), the spatial orientation test (SOT), and the 4 mountains test (4MT). As a result of our study, cochlear implant users with otolith dysfunction in TCT showed a greater angle of deviation and distance of deviation compared to those without otolith dysfunction and healthy controls (p<0.001). There was a significant difference between the groups in the UOT angle difference values (p<0.001). Cochlear implant users with otolith dysfunction had the highest angle difference, while healthy controls had the lowest angle difference. On the other hand, in 4DT, cochlear implant users with and without otolith dysfunction had a higher error number compared to healthy controls (p<0.005). While otolith dysfunction was effective in spatial navigation skills, it was found that hearing loss was more effective in spatial memory skills. It has been observed that both otolith dysfunction and hearing loss affect spatial orientation ability. It has been found that cochlear implant users have poorer spatial cognition skills, and users with otolith dysfunction have lower performance in spatial cognition, spatial navigation, and orientation skills. Our study is the first to evaluate spatial cognition skills in individuals with cochlear implants, considering otolith dysfunction.