Auditory Training: Consideration of Peripheral, Central-Auditory, and Cognitive Processes

It has been 8 years since Seminars in Hearing published an issue devoted to auditory training (2007, issue no. 2). Much has happened in the research literature during this time. In 2005, Sweetow and Palmer wrote the first systematic review investigating the efficacy of auditory training in adults.[1] The review included six studies with varying levels of evidence. Three were randomized controlled trials, two were nonrandomized controlled trials, and one used a repeated-measures design. Only one study assessed participants both immediately posttraining and at a later follow-up evaluation. Additionally, all of the studies used one-on-one in-person auditory training. This important review highlighted the need for high-quality auditory training research demonstrating efficacy, effectiveness, and efficiency

Eight years later, in 2013, Henshaw and Ferguson published a systematic review of computer-based training for adults with hearing loss.[2] The review included 16 studies, again, with varying levels of evidence. Three of the studies were randomized controlled trials, two were nonrandomized controlled trials, and seven used a repeated measures design. Six of the studies included follow-up testing at least 1 month after training was completed.

Both systematic reviews included several studies that demonstrated improved speech perception for trained materials; however, there were limited findings demonstrating generalizability to untrained materials and talkers. The Henshaw and Ferguson review included seven studies in which training occurred at home; five of these studies reported very high compliance (greater than 90%), and two reported fair compliance (around 75%). Consideration of compliance (and efficiency) is important as higher compliance will likely result in better outcomes.

The articles in the current issue describe exciting research that addresses several of the problems identified in the previous systematic reviews.[1] [2] This collection of articles moves beyond the examination of auditory training primarily for adult hearing aid users. The articles discuss the central auditory and cognitive processes that impact speech communication in children and adults who may or may not have peripheral hearing loss. The first two articles describe and investigate auditory training in children with central auditory processing disorders. The article by Weihing and colleagues is a general overview of this topic, whereas the article by Cameron and coworkers evaluates a large-scale central auditory processing program in clinical practice. The next three articles consider the role of auditory training and higher-order central/cognitive processes in adults. Ferguson and Henshaw propose an integrated auditory-cognitive training approach to optimize real-world communication. Anderson and Jenkins demonstrate the usefulness of neural coding as an outcome measure for auditory training, whereas Sommers et al demonstrate the usefulness of listening effort as an outcome measure. Following these articles, Miller and colleagues review the importance of inherent and situational context in speech perception training. They then describe their ongoing multisite randomized controlled trial measuring the efficacy of this training in (approximately) 240 adult hearing aid users. The final two articles discuss real-world applications of auditory training. Olson provides a useful review of specific computer-, tablet-, and smartphone-based auditory training programs and considers their usefulness in the promotion of both patient centered care and self-management. Plant et al evaluate the benefits of short-term and long-term auditory training in adult cochlear implant users. Interestingly, the authors consider the impact of auditory training not only on speech perception but also on self-perceived competence and confidence. Once again, we see the interrelationships between auditory training, speech perception, central auditory processing, and cognitive functions.

In the articles that follow, several of the authors lament the fact that auditory speech perception training is not standard within audiology clinical practice. Olson speculates that this is due to the lack of time and reimbursement and the lack of compelling evidence demonstrating effectiveness. The articles presented here consider new methods to improve the effectiveness of auditory training and describe novel outcome measures to demonstrate efficacy. With better training methods, improved outcome measures, and ongoing high-quality research, we may soon see a higher uptake of auditory training in the practice of audiology.

• References

• 1 Sweetow R, Palmer CV. Efficacy of individual auditory training in adults: a systematic review of the evidence. J Am Acad Audiol 2005; 16 (7) 494-504
• 2 Henshaw H, Ferguson MA. Efficacy of individual computer-based auditory training for people with hearing loss: a systematic review of the evidence. PLoS ONE 2013; 8 (5) e62836