Everyone blames phonological representations for language-related impairments, or deficits in phonology-related tasks like nonsense-word repetition. But what is a phonological representation? What do impaired phonological representations look like? In what specific ways do they differ from unimpaired representations, and how can you tell? What does it all mean?!
Munson (2006) in a commentary on Gathercole’s keynote article in Applied Psycholinguistics expatiates thus, and I can only concur:
Although there are many different perspectives on the factors that drive nonword repetition performance, we can all agree that the relationship between nonword repetition and word learning is due to the association of these constructs with phonological representations. The relevant question to ask, then, concerns the nature of phonological representations themselves. What are they? Textbook descriptions of these generally posit that they look something like the strings of symbols that we are taught to transcribe in phonetics classes. However, phonetic transcriptions, even narrow ones, are abstractions of the signals that are being transcribed. The level of detail that they code is ultimately related more to the perceptual abilities of the listener, the degrees of freedom in the symbol system, and a priori assumptions about the quantity of detail that is relevant for transcription than to the signal being transcribed and its associated phonological representation.
What, then, do “real” phonological representations encompass? What is being represented? The answer to that is anyone’s best guess. Representations themselves are latent variables. We can never see them, we can only posit them as explanations for the sensitivity that people have to variation and consistency in the speech signal in different tasks. (p578)
A welcome reality check in perhaps a slightly unexpected place, even though, of course, it still doesn’t solve the fundamental problem. Everybody’s preferred solution for testing the true nature of implicit phonological representations is different, and inadequate to different degrees and in different ways, but in the nature of the concept of phonological representations itself, that is simply how it has to be.
Munson, B. (2006). Nonword repetition and levels of abstraction in phonological knowledge. Applied Psycholinguistics 27: 4