Dawes et al report that auditory processing disorders (APDs) are diagnosed based on listening difficulties despite normal hearing, the cause of which is unknown. They report that current APD assessment and identification methods appear to have “serious shortcomings” and APD definitions often list a set of auditory skills (discrimination, pattern recognition, temporal integration, etc.) thought to be impaired. However, these same skills are broad, may overlap, and, indeed, do appear to be based on a core of fundamental auditory skills such as temporal processing, auditory figure-ground discrimination, and auditory memory or attention.
In their study, they evaluated whether APD is modality-specific with regard to auditory temporal processing and evaluated the auditory impairment differences among children diagnosed with APD versus those diagnosed with dyslexia. Participants included 22 children with APD, 19 children with dyslexia, and a normative group consisting of 98 children.
The authors report that the diagnosis a child receives may be significantly related to the particular professional consulted. For example, an audiologist, speech-language pathologist, and a pediatrician might diagnose APD, a language disorder, or ADD/ADHD (respectively) given the same signs and symptoms in the same child. Further, non-auditory factors may impact APD test performance (hunger, tiredness, boredom, etc.) and thus, children who do not have APD may be categorized as having APD. The authors note use of linguistic stimuli in APD tests is problematic, too, with regard to language level, accent, word familiarity, etc.
The authors reported no significant differences between the APD and the dyslexia group’s performance and no evidence supporting a specific temporal auditory impairment as the underlying cause of APD. Across the APD and dyslexia groups, similar proportions demonstrated poor auditory performance—not accounted for entirely by performance IQ or attention. The authors report that auditory perceptual deficits may be better thought of as a multifactorial description of learning problems rather than a unique diagnostic descriptor and they reported auditory impairments co-occur with literacy problems, although they may not be directly related. Additionally, the authors report distinguishing between children based on categories such as APD or dyslexia may be counterproductive as it focuses attention on one issue, while there may be multiple issues that would benefit from attention.
For More Information, References, and Recommendations
Dawes P, Sirimanna T, Burton M, Vanniasegaram I, Tweedy F, Bishop DVM. (2009) Temporal Auditory and Visual Motion Processing of Children Diagnosed with Auditory Processing Disorder and Dyslexia. Ear & Hearing 30(6):675–686.