Table 1.
Cochlear implant participant details.
Figure 1.
Best-ear un-aided audiogram results from the HA group. Hearing thresholds are given in dB HL. The fundamental frequency of the melody notes is shown by the black triangles on the x-axis.
Table 2.
Hearing aid participant details.
Figure 2.
The simple 4-note melody (G, C, A, D, midinotes 67, 72, 69, 74) depicted on the stave used as the visual display. Each melody note turned red as it played. The scale to the right repeated the participants' response in real time, so they did not have to look away from the screen to gauge their response.
Figure 3.
Electrodogram for melody notes.
An “electrodogram” showing the stimulation across electrodes (on the y-axis) over time, as the 4-note melody is repeated three times. The first note of the melody starts at time 0. The electrodogram was generated by RFStatistics software (Hearing CRC, Melbourne).
Figure 4.
Decreasing (DEC: upper panel) and increasing (INC: lower panel) blocks are shown. Melody notes (black/dark dots) play continuously. Distracter notes (red/light dots) are interleaved with the melody notes, and are selected from a range of 12 consecutive midinotes (an octave). The distracter note range is increased or decreased by one midinote per level, for 20 levels. Within each level, the melody is repeated 20 times (a single presentation is shown here).
Figure 5.
Difficulty ratings across distracter note levels.
Top panel: Difficulty ratings (+/- SEM), averaged across INC and DEC blocks, as a function of distracter note level, with visual cues provided (red triangles) and with no visual cues (black squares). Bottom panel: the reduction in difficulty provided by the visual cue.
Figure 6.
Mean difficulty ratings across all distracter separation levels. Significant differences (Tukey HSD test) between groups and conditions are indicated with horizontal bars.