Oh, /ɹ/. Here we… /ɹ/ again. Our “not-new” norms (see here) tell us that /ɹ/ is typically acquired by 5–6 years of age, but wouldn’t it be great to know even earlier which /ɹ/ distortions will resolve on their own and which will require treatment? Turns out, we might be able to do it by taking our eyes off that tricky rhotic for a minute and paying attention to our old, early-acquired friend /w/. /w/-hat?! 
 

This new study by Munson et al. looked at American 3–5-year-olds’ productions of /ɹ/ and /w/ at two points in time, one year apart. They found that the presence of distortions in /w/ in early preschool may be predictive of poor improvement in /ɹ/ productions between 4–5 years old. On the other hand, children with very accurate productions of /w/ early on were more likely to show spontaneous improvements in /ɹ/.

“Children with those subtle deviations [of /w/] might be prioritized for early treatment of /ɹ/.”

 

– Munson et al., 2021

The trick here is that to notice this pattern at all, you might need to adjust how you conceptualize and record the accuracy of kids’ productions—meaning, you gotta switch up your /ɹ/-chaic data tracking. If you use what the authors call a “lenient” scoring system, where you count productions with minor distortions that still sound mostly like the attempted sound as just straight-up correct, you might totally overlook these telltale /w/-iggles. Instead, you could consider using a stricter system, where a production has to be totally accurate to get that plus sign on your data sheet—as long as you’re somehow tracking whether the errors are distortions, omissions, substitutions, etc. Another good option is to use a VAS for scoring (as we’ve discussed here and here), so you can capture a full spectrum of accuracy. 

So what else /ɹ/ we taking away here? 

• When evaluating preschoolers’ speech, record any distortions in /w/ productions to help you identify the students whose /ɹ/-ticulation issues may linger. This can help you better counsel parents by giving one more piece of prognostic information.
• If you’re on-site, you can monitor the students with /w/ distortions so they can be picked up as early as possible. You’ll also be able to consult with teachers more effectively—identifying kids to keep an ear on and providing some targeted strategies they can use in the classroom.

Side note: If you want more information on treating /ɹ/, see here and here. If you need a refresher on the “not-new” speech sound norms, see this Ask TISLP.

Disclosure: Karen Evans, MA, CCC-SLP, contributed to and edited this review. She was previously supervised by the first author of this paper and has co-authored another paper with him. 

Munson, B., Logerquist, M.K., Kim, H., Martell, A., & Edwards, J. (2021). Does early phonetic differentiation predict later phonetic development? Evidence from a longitudinal study of /ɹ/ development in preschool children. Journal of Speech, Language, and Hearing Research. https://doi.org/10.1044/2021_JSLHR-20-00555  [available to ASHA members]