Investigation of speech perception for patients with a cochlear implant supported with a hearing aid

The investigations were carried out for 5 listeners with a cochlear implant, 2 male and
3 female at implantation age 13–62 years. The deafness for 4 subjects was recognized as
postlingual and for 1 – as perilingual. All listeners were using the hearing aid on the opposite
ear to the implant. The speech intelligibility was determined in two cases: when transmission
was only via the implant and when the hearing aid was also used. Additionally, the ability
of discrimination of male and female voices was performed. The presentation of tests was
conducted for three angles (0$^{\circ}$, −90$^{\circ}$ and+90$^{\circ}$) in relation to the listener’s head for the levels
equal to 50, 65 and 80 dB SPL. The Polish monosyllabic word tests (PRUSZEWICZ et al., [4])
were applied. The improvement of the speech intelligibility was affirmed when the process of
hearing via the implant was supported with a hearing aid. The particularly essential differences
in the speech intelligibility was observed for angle +90$^{\circ}$ (HA-side). The results obtained in
the investigations show that acoustic compensation in the range of remaining audibility field
in a great degree supports electrical hearing.