(Cross-posted at FacilitatedCommunication.org).
In my last post I wrote about motor difficulties in autism and argued that these challenges, however widespread they may be, do not explain away the myriad empirical problems with facilitated communication. In this follow-up post I’d like to zero in on one particular motor control issue: motor planning, AKA apraxia. My reasons are twofold. First, among the various actual and purported motor difficulties in autism, apraxia is the one most often cited by FC proponents. Second, one of the most common critiques levied by FC proponents against FC critics is that we don’t understand apraxia and how it validates FC.
For FC proponents, the story goes as follows. Apraxia, specifically apraxia of speech, is the reason for both the deficits in, and the purported unreliability of, speech in severe autism. Meanwhile, a more general apraxia is the purported reason for index-finger typing that is facilitated (whether through touch, verbal prompts, and/or held-up letterboards) by a designated communication partner who is always within tactile, auditory, and/or visual cueing range. This more general apraxia is also the purported reason for discrepancies between the FCed messages and ways in which the facilitated person actually behaves—whether before, after, or during facilitation.
Let’s start with what FC proponents say about apraxia of speech. Many proponents, from Douglas Biklen (Biklen et al., 1992), who introduced FC to the U.S., to Elizabeth Vosseller, who is credited with inventing one of the most recent variants of FC (Spelling to Communicate or S2C), argue that apraxia of speech is part of a more general language apraxia that also includes ten-finger typing. This apraxia, they say, amounts to a disconnect between the motor and language systems of the brain. According to one of the FC proponents mentioned in my last post, “They say things that they didn’t intend to say”.
But that’s not quite what the professionals say about apraxia of speech (commonly abbreviated as AOS), AKA childhood apraxia of speech (commonly abbreviated as CAS). For those who actually specialize in speech-language disorders, AOS/CAS (1) does not include ten-finger typing, and (2) involves something much more specific than a general disconnect between motor and language systems or saying things you didn’t intend to say. Core to AOS/CAS, rather, is difficulty planning and coordinating your speech movements. This might, for example, involve saying “totapo” or “topato” instead of “potato.”
As defined by the American Speech Language Hearing Association (ASHA), AOS/CAS involves:
- A limited consonant and vowel repertoire.
- Minimal variation between different vowel sounds.
- Vowel errors and distortions.
- Inconsistent errors and idiosyncratic error patterns.
- Reduced rate or accuracy with diadochokinetic tasks [how quickly you can accurately repeat a series of rapid, alternating sounds like “puh-tuh” and “puh-tuh-kuh”]
- Oral groping behaviors [resorting to trial and error tactics for making speech sounds]
- Prosodic differences (reduced rate, excess or equal stress, “choppy” words and syllables, monotone speech).
- Increased errors with increased length or complexity of utterances.
- More difficulty with volitional utterances compared to modeled or automatic utterance.
And according to ASHA’s Technical Report, AOS/CAS involves:
1. inconsistent errors on consonants and vowels in repeated productions of syllables or words;
2. lengthened and disrupted coarticulatory transitions between sounds and syllables; and
3. inappropriate prosody, especially in the realization of lexical or phrasal stress.
As Terband et al. note, ASHA’s definition of AOS:
has been adopted widely in the CAS [Childhood Apraxia of Speech] research literature (e.g., Grigos & Kolenda, 2010; Iuzzini-Seigel, Hogan, Guarino, & Green, 2015; Maas & Farinella, 2012; Murray, McCabe, Heard, & Ballard, 2015; Namasivayam et al., 2015; Preston et al., 2014; Terband, Maassen, Guenther, & Brumberg, 2009, 2014).
As Cassidy (2016) sums up AOS:
Patients with apraxia of speech have very slow, deliberate, effortful speech. They may make errors in the shape, ordering and timing of the production of individual syllables and may display ‘articulatory groping’, repeatedly correcting themselves while trying to find the right word or sound. They also have greatly impaired prosody of speech, such that it loses its natural rhythm, intonation and overall melody. .. they then often struggle significantly when asked to string a number of syllables together (eg, ‘pa-ta-ka, pa-ta-ka, …’).
One way to get real a handle on what AOS is and what AOS isn’t is to look at how it’s evaluated. According to the Mayo Clinic, in an AOS evaluation:
Your child’s ability to make sounds, words and sentences will be observed during play or other activities.
Your child may be asked to name pictures to see if he or she has difficulty making specific sounds or speaking certain words or syllables.
Your child’s speech-language pathologist may evaluate your child’s coordination and smoothness of movement in speech during speech tasks. To evaluate your child’s coordination of movement in speech, your child may be asked to repeat syllables such as “pa-ta-ka” or say words such as “buttercup.”
If your child can produce sentences, your child’s speech-language pathologist will observe your child’s melody and rhythm of speech, such as how he or she stresses syllables and words.
Your child’s speech-language pathologist may help your child be more accurate by providing cues, such as saying the word or sound more slowly or providing touch cues to his or her face.
Gubiani et al. (2015) describes several specific tests: the Verbal Motor Production Assessment for Children (VMPAC), the Dynamic Evaluation of Motor Speech Skill (DEBMP), the Kaufman Speech Praxis Test for Children (KSPT), and the Madison Speech Assessment Protocol (MSAP). Across these tests, the majority of items involve imitating increasingly complex vowel and consonant combinations. The KSPT, for example, has the child imitate isolated vowels, vowel combinations (diphthongs) like “ai” and “ou”, consonants, different types of syllables and repeated syllables, and, finally, spontaneous speech. And the DEBMP has the child imitate consonant-vowel (e.g., “me” and “hi”), vowel-consonant (e.g., “up” and “eat”), duplicate syllables (e.g., “mama” and “ booboo”), consonant-vowel-consonant (e.g., “mom” and “bed”), two syllable words (e.g., “baby” and “ happy”), multisyllabic (e.g., “banana” and “kangaroo”), and increasingly long phrases (e.g., “dad,” “hi dad,” “hi daddy”).
Terbald et al. (2019) also discuss specific tasks for diagnosing AOS/CAS that appear across a wide range of AOS studies. These include multi-syllabic words like “elephant” and “spaghetti”; phrases involving consonant repetitions (“Buy Bobby a puppy” and “Well we’ll will them”) or a variety of consonants (“Tony knew you were lying in bed”); nonsense word repetitions (e.g., “pib”, and “pub”); repetitions of contrasting minimal pairs (e.g., “pil–bil”, “tennis–dennis”); one-, two-, and three-syllable words (“pop,” “puppet,” and “puppypop”) repeated multiple times in random order; repetitions of a variety of different consonant-vowel combinations; and pronunciation of multisyllabic words with a variety of stress (accent) patterns. In discussing error types, Terbald et al discuss phonetic distortions, phonemic errors, and prosody errors.
As Gubiani et al. put it, what these AOS tests have in common is that they assess “the oral structures and/or motor function of speech”, and to some extent, the child’s speech prosody [speech rhythm and melody]. All this is consistent with how AOS is characterized both by ASHA and by the Mayo Clinic.
As far as FC is concerned, the takeaway here is that AOS is about difficulty reliably producing words, particularly complex ones like “potato”, not difficulty suppressing incorrect words. A child with apraxia who intends to say “potato” might reverse the sounds and say “topato”; what he or she won’t do is land on a phonetically unrelated word like “blanket.” That is, while AOS involves making sounds you didn’t intend to make because of difficulties with motor planning, it doesn’t involve saying completely different words from those you intended to say. And so, for example, AOS does not involve saying “No more! No more!” while you’re typing out a message about telling someone how you feel about them.
Two other things are worth noting. One is that, within the subpopulation of autistic individuals who produce little-to-no speech, AOS is impossible to diagnose. True, ASHA’s first criterion is “a limited consonant and vowel repertoire.” But this, alone, isn’t diagnostic: there are other disorders that limit consonant and vowel production. What distinguishes AOS is difficulty producing combinations of vowels and consonants, as well as inconsistent successes and failures. The smaller a child’s consonant and vowel repertoire, the harder it is to detect these difficulties and inconsistencies.
Also impossible to diagnose are those who don’t respond to prompts to imitate sounds—either because they lack the receptive language needed to understand these prompts, or because they lack the social motivation to respond. (Both of these factors, it’s worth noting, are hallmarks of severe/profound autism). Furthermore, as I discussed in an earlier post, where severe/profound autism is concerned, there are alternative explanations for non-speaking and minimally-speaking that have nothing to do with apraxia of speech.
Side note: there has been some disagreement on overall rates of AOS in autism. FC proponents have cited one study (Tierny et al., 2015) as showing that 64% of autistic children have apraxia of speech. However, this study only included children with communication delays. Other studies (Shriberg et al., 2011 and Cabral & Fernandez, 2021) find little-to-no correlation between autism and AOS.
Moving beyond AOS, what sort(s) of apraxia accounts for facilitated, index-finger typing and for discrepancies between the FCed messages and ways in which the facilitated person actually behaves?
Biklen, as we saw, included independent typing under a more general sort of language apraxia. This, purportedly, could be remediated via classic FC: by stabilizing the individual’s hand movements (see also Crossley & McDonald, 1980; Jacobson et al., 1995). As I noted in my last post, however, pointing difficulties do not come up in any of the published research or assessments of motor challenges in autism, apraxia included.
Vosseller, meanwhile, claims that index finger typing, as opposed to speech and ten-finger typing, is a gross motor activity, and so is a way to bypass the purported fine-motor apraxia that she and other S2C proponents claim characterizes autism. As I noted in my last post, however, pointing is a fine motor skill, not a gross motor skill.
So much for those arguments.
And for discrepancies between the FCed messages and ways in which the facilitated person actually behaves, we mostly have anecdotal reports: specifically, reports extracted, through FC, from facilitated individuals. Philip Reyes, for example, purportedly claims (via the Rapid Prompting Method, or RPM) that apraxia causes “my body [to do] something foolish like throwing a random object instead of obeying the order of cleaning up.” And Ben Breaux purportedly claims, also through RPM, that, due to apraxia, he is unable, when asked, to put three teaspoons of sugar in a cup until he types out what the steps are (via RPM).
There is a grain of truth here, inasmuch as apraxia can involve difficulties with motor sequences. But the sorts of apraxia recognized by actual experts do not include the phenomena described here by Breaux. Proposed non-speech apraxias (see Wikipedia for a review) include limb-kinetic apraxia (which mostly pertains to finger movements, e.g., tying shoes or typing); gait apraxia (difficulty walking); constructional apraxia (e.g., difficulty copying a simple diagram or drawing basic shapes); and oculomotor apraxia (difficulty moving the eyes on command). Some have argued, however that the last three aren’t true instances of apraxia, as apraxia, by definition, “involves skilled motor tasks secondary to a disturbance of higher level motor function” (See Cassidy, 2015).
Possibly more relevant to the claims attributed to Philip Reyes and Ben Breaux, at least at first glance, are two other sorts of apraxia: ideational apraxia and ideomotor apraxia.
In ideational apraxia (see Cassidy, 2015), “the concepts of movement and intent are degraded” and patients may lack “conceptual or semantic knowledge” about the appropriate use of a particular tool. As Cassidy explains:
Patients presented with a pair of scissors, for example, can name the object correctly but may be unable to describe their use. When the examiner demonstrates their use, patients may be unable to discriminate between poorly executed movements and properly executed movements. When handed the item themselves, they may struggle to use them to cut a sheet of paper.
…
The idea is that a patient with ideational apraxia may be unable to demonstrate the action because they have lost the semantic memory associated with the tool, but if they can see how it should be used then they can still access their largely intact action production system to then produce a good imitation…
Ideomotor apraxia, meanwhile, involves impairments in the action production system. It impairs, in particular, the ability to pantomime. As Cassidy explains:
Affected patients display errors in the scaling, timing and orientation of movements and may also omit or repeat individual elements of the overall action being assessed. They… often perform poorly when asked to pantomime an action. A common error is the ‘body-part-as-object error’, where the patient substitutes a body part for the tool in question when asked to pantomime a particular action…
Despite these difficulties, the goal of the action can usually be recognised, and… the patient’s performance significantly improves if they are given the object they have just been asked to pantomime…
Neither ideomotor nor ideational apraxia, on close inspection, includes difficulties in adding three teaspoons of sugar to a cup that go away when you first type out the directions, let alone throwing a random object instead of cleaning up a room.
The more I think about those discrepancies between what a person types and how they act—whether or not FC is part of the picture—the more I think of a certain old saying that often gets lost in the dust.
Actions speak louder than words.
REFERENCES/FURTHER READING
ASHA Technical Report on Childhood Apraxia of Speech https://www.asha.org/policy/tr2007-00278/
Biklen, D., Morton, M. W., Gold, D., Berrigan, C., & Swaminathan, S. (1992). Facilitated communication: Implications for individuals with autism. Topics in Language Disorders,12(4), 1-28. https://doi.org/10.1097/00011363-199208000-00003
Cassidy A. (2016). The clinical assessment of apraxia. Practical neurology, 16(4), 317–322. https://doi.org/10.1136/practneurol-2015-001354
Cabral, C., & Fernandes, F. (2021). Correlations between autism spectrum disorders and childhood apraxia of speech. European Psychiatry, 64(Suppl 1), S209. https://doi.org/10.1192/j.eurpsy.2021.557
Crossley, R. 1997. Speechless: Facilitating Communication for People Without Voices. Dutton.
Gubiani, M. B., Pagliarin, K. C., & Keske-Soares, M. (2015). Tools for the assessment of childhood apraxia of speech. CoDAS, 27(6), 610–615. https://doi.org/10.1590/2317-1782/20152014152
Shriberg, L. D., Paul, R., Black, L. M., & van Santen, J. P. (2011). The hypothesis of apraxia of speech in children with autism spectrum disorder. Journal of autism and developmental disorders, 41(4), 405–426. https://doi.org/10.1007/s10803-010-1117-5
Terband, H., Namasivayam, A., Maas, E., van Brenk, F., Mailend, M. L., Diepeveen, S., van Lieshout, P., & Maassen, B. (2019). Assessment of Childhood Apraxia of Speech: A Review/Tutorial of Objective Measurement Techniques. Journal of speech, language, and hearing research : JSLHR, 62(8S), 2999–3032. https://doi.org/10.1044/2019_JSLHR-S-CSMC7-19-0214
Tierney, C., Mayes, S., Lohs, S. R., Black, A., Gisin, E., & Veglia, M. (2015). How Valid Is the Checklist for Autism Spectrum Disorder When a Child Has Apraxia of Speech?. Journal of developmental and behavioral pediatrics : JDBP, 36(8), 569–574. https://doi.org/10.1097/DBP.0000000000000189
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