ACQ Vol 12 no 1 2010

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ACQ Volume 12, Number 1 2010 3
Motor speech disorders
that feedback in the prepractice phase should be about
how the person is making the sound or the error. Speech
pathologists use this type of feedback frequently; however,
the rub is that in the practice phase, feedback should only
be on whether the target was correctly produced. This
will require a change of behaviour for most clinicians and
PML tells us that clinicians will need to practise their own
new behaviour to institute this change. In addition, the
client should only be told whether they got it right or not on
randomly selected productions at a rate of less than 100%
of productions (Hodges & Lee, 1999).
In the last three years there have been a number of
papers which examine how these principles may apply
generically to speech and voice interventions (e.g., Maas
et al., 2008; McIllwaine, Madill, & McCabe, this issue), and
new treatments which have been designed with PML as the
underlying theoretical framework are being created (Ballard,
Robin, McCabe, & McDonald, 2009). Therefore, PML may
change our practice across movement disorders and provide
a theoretical basis from which to make clinical decisions in
the absence of high level evidence to guide practice.
Returning to traditional articulation intervention, it is
interesting that in the era of evidence based practice most
speech pathologists unquestioningly accept it as being
best practice even though there are no large-scale, high
level studies to support this assumption. A recent search
(30 October 2009) of speechBITE )
provided 100 treatment papers in which articulation was a
keyword. In 14 of these, traditional articulation intervention
was examined most commonly as a control intervention
against which a newer treatment was being compared.
Three were regarding children with cleft and 11 were about
otherwise typically developing children. Of these 11 papers
none were systematic reviews, 4 were small randomised
control trials, 3 were other types of control trials and the
remainder were lower levels of evidence. Eight papers had
been rated by speechBITE, and only two papers scored
5/10 indicating moderately rigorous research; the other
papers were rated between 1/10 and 4/10 (lower levels
of rigour). Most papers supporting traditional articulation
intervention are thus low level evidence. However,
recognition of this issue does not help us make clinical
decisions as, like many areas of speech pathology practice,
there are no alternate treatments available. What clinical
experience tells us is that traditional articulation intervention
generally works; however, articulation is a motor speech task
and therefore PML might be applied to improve treatment
efficiency and effectiveness.
To use PML in an articulation session we could, for
example 1) only give cues about how to make the sound
until the child gets a few productions correct (prepractice),
2) rapidly move on to feedback about correctness
(practice), and 3) ensure that the client has mixed practice
opportunities rather than repeated productions of the same
Motor learning in speech pathology could
refer to any area of practice which changes how a
movement is made in relation to a communication or
swallowing outcome. This obviously includes speech issues
associated with articulation, apraxia, dysarthria, and fluency.
However we can also think about motor learning in relation
to voice therapy, swallowing intervention, or skilled use of
augmentative and alternative communication (AAC). These
areas of practice are thus about motor learning in a broader
sense, as we endeavour to institute, change, or repair a set
of learnt movements.
This motor speech issue of ACQ focuses on an area of
practice that has often been neglected in both research
and practice over the last couple of decades. Indeed,
some of the treatments we use in motor speech come from
the very foundation days of the profession. For example,
most paediatric clinicians will use a variation of van Riper’s
(1939) stimulus approach as the basis for traditional
articulation intervention. We are now witnessing an explosion
in theoretical knowledge about how motor behaviours
are learnt, processed, perceived, and stored. This new
knowledge will in turn influence therapeutic approaches to
motor intervention. This editorial will review some of the most
promising areas of research (principles of motor learning,
neurological plasticity, and mirror neurones) and hypothesise
how motor interventions may change in the coming years.
Principles of motor learning
In recent years the term ‘principles of motor learning’ (PML)
has appeared in the speech pathology literature. These
principles derive from research in the fields of learning and
motor rehabilitation. For a detailed review of PML see Maas
et al. (2008). What do these principles tell us about motor
learning? This paper is too short to go through all of them
but three examples follow. First, there are two phases in
learning any new motor skill – called prepractice and
practice. Prepractice is the introduction of a new skill and
practice is the period in which the skill is embedded as a
habitual behaviour and generalised where appropriate.
Second, to learn any new motor skill lots of varied practice is
required. This might seem like an old idea but research is
consistently showing that practice needs to occur, not over
tens or hundreds of blocked trials, but over thousands of
disseminated ones. So if you want a new speech sound to
generalise then the client needs to practise, practise,
practise. Implied in the concept of varied (or disseminated)
practice is also a notion that clients should practise on
multiple, related, randomised production targets; that is,
simultaneously target the sound in initial, medial, final
positions and possibly clusters. Randomisation allows for the
development of a general motor plan rather than a context
specific motor plan and is the key to greater learning.
Finally, we may need to change the way in which we
provide feedback as well as its content. PML tells us
Editorial
Advances in motor learning: Emerging evidence and new ideas
Patricia McCabe
Patricia McCabe