Use of auditory learning to manage listening problems in children

Abstract

This paper reviews recent studies that have used adaptive auditory training to address communication problems experienced by some children in their everyday life. It considers the auditory contribution to developmental listening and language problems and the underlying principles of auditory learning that may drive further refinement of auditory learning applications. Following strong claims that language and listening skills in children could be improved by auditory learning, researchers have debated what aspect of training contributed to the improvement and even whether the claimed improvements reflect primarily a retest effect on the skill measures. Key to understanding this research have been more circumscribed studies of the transfer of learning and the use of multiple control groups to examine auditory and non-auditory contributions to the learning. Significant auditory learning can occur during relatively brief periods of training. As children mature, their ability to train improves, but the relation between the duration of training, amount of learning and benefit remains unclear. Individual differences in initial performance and amount of subsequent learning advocate tailoring training to individual learners. The mechanisms of learning remain obscure, especially in children, but it appears that the development of cognitive skills is of at least equal importance to the refinement of sensory processing. Promotion of retention and transfer of learning are major goals for further research.

Figure 1

Improved language skills following phoneme discrimination training. Performance of trained (open square) and untrained (filled square) children before (pre), immediately after (post) and five to six weeks after (delayed) a four-week period during which the trained group performed phoneme discrimination exercises three times/week. Scores on the outcome measure (the four receptive sub-tests of the Phonological Assessment Battery; Frederickson et al. 1997) are referenced to the normalized (age-appropriate standard score) British values. Analysis of variance showed a highly significant training effect with no subsequent improvement (or decline) at the delayed test. The untrained group, who engaged in normal classroom activities while the other group trained, did not differ significantly between the pre and post tests. Data bars show group means. Error bars in all figures are standard errors. Adapted and modified with permission from Moore et al. (2005).

Figure 2

Types of listening performance in children. Each panel shows the results of successive, 3-down, 1-up staircase, adaptive tracks of trials in three individual children. The ordinate shows the frequency difference between the standard and target stimuli. (a) Good (typical) performers produced consistent responses at low threshold levels (black circle, track 1; white circle, track 2; grey circle, track 3). (b) Genuine poor performers were consistent, but had elevated thresholds. This behaviour was suggestive of a ‘sensory’ form of APD. (c) Non-compliant responders generally performed well in the first few trials of each track, but performance then declined, either to ceiling level (as here) or to a level close to, or above the starting level of the track. Performance often recovered towards the end of the track. This behaviour was suggestive of an ‘attentive’ form of APD. The examples shown are from (a) a 10-year-old, (b) a 9-year-old and (c) an 8-year-old child. Further details in the text. Adapted with permission from Moore et al. (2008a).

Figure 3

(a) Frequency discrimination learning curves for listeners with ‘better’ and ‘poorer’ initial performance, trained using a single (‘fixed’) standard frequency of 1 kHz or 5 different (‘varying’) standard frequencies (570, 840, 1170, 1600 and 2150 Hz) varied on a trial-by-trial basis. Frequency discrimination thresholds are presented as per cent difference between the standard and comparison (target) tone frequencies relative to the frequency of the standard. For listeners trained on varying frequencies, the results are averaged across frequencies (thresholds did not differ significantly between frequencies). (b) Transfer of learning tested at various untrained frequencies (each tested using a fixed standard frequency). Fixed: filled triangle, better; open triangle, poorer. Varying: filled circle, better; open circle, poorer. Figure adapted with permission from Amitay et al. (2005).

Figure 4

Frequency discrimination learning curves for listeners trained using a single, fixed standard frequency (filled triangles) of 1 kHz or 5 different frequencies (900, 950, 1000, 1050 and 1100 Hz) varied either on a trial-by-trial basis (filled circles) or a block-by-block basis (open circles). Frequency discrimination thresholds are presented as per cent of the standard (comparison) tone frequency. For listeners trained on varying frequencies, the results are averaged across frequencies (thresholds did not differ significantly between frequencies). Figure adapted with permission from Moore & Amitay (2007).

Figure 5

Frequency discrimination learning of a 1-kHz tone for 800 trials of frequency discrimination training using either adaptive tracking of the threshold at 75% correct (‘adaptive’), no difference between stimuli (0 Hz), or a large, fixed difference (400 Hz). Adapted with permission from Amitay et al. (2006b).

Figure 6

Frequency discrimination learning curves for 6- to 11-year-old children and adults trained using a single fixed standard frequency of 1 kHz. Frequency discrimination thresholds are presented as per cent of the standard (comparison) tone frequency. Open circle, 6–7 years; open triangle, 8–9 years; filled circle, 10–11 years; filled triangle, 18+ years. Adapted with permission from Halliday et al. (2008).

Figure 7

Individual and group frequency discrimination learning curves for (a) ‘Non-adult-like’ children who did not achieve adult-like frequency discrimination thresholds at any point during the training session, (b) ‘Trainable’ children who did not have frequency discrimination thresholds at the outset of training, which were similar to those of naive adults but nonetheless went on to achieve this during the training session (thin line, individual; thick line, group mean) and (c) ‘Adult-like’ children who had frequency discrimination thresholds at the start of training, which were similar to those of naive adult listeners. Adapted with permission from Halliday et al. (2008).