Computerised Therapy in Chronic Stroke
Does Inner Speech Improve Access to Overt Speech in Aphasia Following Stroke? An fMRI Study Utilising Computerised Rehabilitation Software.
The few studies looking systematically into the neurophysiological and neuropsychological
components of available therapies for chronic aphasia are highly heterogeneous in nature.
Results from these studies have, unsurprisingly, indicated heterogeneous results, such as
dissimilar neural outcomes associated with neuropsychological gains. There is, therefore, no
consensus of how a successful therapy— that is, one that produces a measurable language gain
in either production or comprehension —impacts the functional language networks of the brain
in a specific type of aphasia population.
A recent study has shown that inner speech (the imagination of speech) involves networks and
areas dissociable from those implicated in speech production. Further, behavioural analysis
has shown an interesting discrepancy between inner speech and overt speech (also called
speech production) in a small chronic aphasia population: some participants elicited poor
inner speech coupled with relatively intact overt speech, while others elicited relatively
intact inner speech coupled with poor overt speech. This unexplored discrepancy implies that
inner speech and speech production are dissociable, though share similar networks.
This discrepancy, and the notion that these speech components share a similar network,
drives this study's hypothesis that improvement in speech production after rehabilitation
might be facilitated by an intact inner speech network. Much as good athletes visualise
their performance before the actual event in order to increase their chances of success, so
too might intact inner speech facilitate speech production, helping to visualise the word in
order to increase the success of produced speech.
By studying a specific component of speech—inner speech—in a relatively homogeneous
population of chronic expressive aphasics, the present study provides an explicit, critical
means of understanding neurophysiological (as assessed by functional magnetic resonance
imaging) and neuropsychological (as assessed by language batteries and personal
questionnaires/interviews) changes occurring during speech therapy.
As a secondary objective, this study will explore the effectiveness, feasibility and
adherence to an at-home computerised aphasia software delivered via a portable tablet.
15 million people worldwide have a stroke each year, with 152,000 in the United Kingdom.
Recent estimates suggest that roughly 33% of patients suffering a stroke develop aphasia, a
loss or impairment of language function caused by brain damage, which can have a significant
impact on all aspects of an individual's life, as well as that of their carers. Aphasia can
often be long-term, or chronic, affecting patients at least a year or more after their
Few studies have systematically investigated the effects of rehabilitation on brain
mechanisms recruited to support recovery in stroke. Studies in this area are highly
heterogeneous. The heterogeneity largely stems from 'lesion-related or language
deficit-related differences in the patients studied'. Participants across and sometimes
within the few studies conducted in this area vary with regard to the type of aphasia or
time-following-stroke. These studies also boast differences including the type and dosage of
treatment, the type of scanning task used to evaluate the desired effects of treatment, and
the type of data analysis employed. Results from these studies have, unsurprisingly,
indicated dissimilar neural outcomes associated with neuropsychological gains, such as
increased right hemisphere (contra-lateral) involvement, or, in contrast, increased
peri-lesional activation. There is, therefore, no consensus of how 'successful therapies'
(that is, those that elicit some kind of language gain, either in comprehension or
production) impact the language networks of the brain.
"It is well known that individuals with aphasia differ greatly with often varying language
patterns and associated lesions, and even study participants carefully selected for their
deficit patterns are seldom, if ever, homogeneous" . People with aphasia will, and do,
differ markedly. Given this predicament, it becomes necessary to systematically control the
other parts of the study, which includes limiting the imaging tasks and analysis to one
component of the language system and using a powerful design, such as a crossover with two
This study therefore aims to use systematic methodology to add information to the diminutive
body of literature concerning chronic aphasia rehabilitation by exploring a specific
component of the language network, inner speech, and its potential influence on speech
production (neurophysiologically and neuropsychologically).
A previous study has shown that inner speech involves networks and areas dissociable from
those implicated in speech production, such as the left inferior frontal gyrus, especially
the pars opercularis and the supramarginal gyrus. Further, behavioural analysis has shown an
interesting interaction of inner and overt speech in a small chronic aphasic population,
whereas some chronic stroke patients showed poor inner speech coupled with good overt
speech, while others showed good inner speech coupled with poor overt speech. This finding
implies an unexplored relationship between the two networks: conceivably, that improvement
in speech production during rehabilitation might be facilitated by an intact inner speech
There are hundreds of aphasia therapies on the market today. In general, two types of
therapy exist: impairment-based and communication-based. Impairment-based therapies are
those that specifically target increasing the ability of components of the language system,
such as naming, reading, writing and sentence structure, and comprise most of the therapies
on the market. Communication-based therapies are more informal, aiming to stimulate
conversation by any means. The most utilised therapies for aphasia include
constraint-induced therapy, which involves constraining the participant to using only words
and not gestures in their communication, thus hoping to free the individual of non-speech
compensatory strategies; melodic intonation therapy, based on the observation that people
with aphasia have a better success rate if singing words rather than just saying words, uses
melody as a crucial component for relearning speech; and various phonological cueing or
naming therapies, which use repetition, semantic and phonological cueing based on specific
anomia (naming) deficits. Aphasia therapies are so prevalent because, unlike drug therapies,
they carry very little risk. This does not mean, however, that each aphasia therapy on the
market is effective for all types of aphasia deficits. The scientific community lacks
understanding of these therapies in several facets: understanding which treatments produce
language gains in specific populations (i.e., chronic vs. acute individuals, fluent vs.
non-fluent aphasia types); how language gains map onto changes in neurological function; and
the trajectory of language gains over time, neuropsychologically and neurologically.
Utilising an at-home computerised aphasia rehabilitation program, this study will explore
whether inner speech can assist patients in restoring access to spoken language, therefore
resulting in improvement of language production (as assessed by neuropsychological
examinations) and instigating changes in functional networks (as assessed by functional
magnetic resonance imaging).
The computerised therapy was chosen because of its detailed clinical output system, its
ability to be personalised to each individual, and its ability to adapt difficulty levels to
the needs of the user. A successful at-home therapy program may provide a means to combat
the lacking resources for continued rehabilitation outside of acute, hospital settings. As a
secondary outcome, this study will investigate the success, feasibility and adherence to
this software by collecting qualitative patient feedback and by analysing the software's
quantitative outputs, such as exercise completion and number of times attempted, total time
used and overall performance on the exercises.
Crossover, Chronic stroke, Stroke, Rehabilitation, Language Therapy, Aphasia, Aphasia Therapy, Computerised Therapy, Computerised Rehabilitation, Tablet, Apps, Aphasia Rehabilitation, Rehabilitation on Portable Tablets
Cambridge University Hospitals NHS Foundation Trust
Cambridge University Hospitals NHS Foundation Trust, Gates Cambridge Trust
Geva S, Jones PS, Crinion JT, Price CJ, Baron JC, Warburton EA. The neural correlates of inner speech defined by voxel-based lesion-symptom mapping. Brain. 2011 Oct;134(Pt 10):3071-82. doi: 10.1093/brain/awr232.
Sharon Geva , Sophie Bennett , Elizabeth A. Warburton & Karalyn Patterson (2011): Discrepancy between inner and overt speech: Implications for post-stroke aphasia and normal language processing, Aphasiology, 25:3, 323-343
Thompson CK, den Ouden DB. Neuroimaging and recovery of language in aphasia. Curr Neurol Neurosci Rep. 2008 Nov;8(6):475-83.
Kiran S, Ansaldo A, Bastiaanse R, Cherney LR, Howard D, Faroqi-Shah Y, Meinzer M, Thompson CK. Neuroimaging in aphasia treatment research: standards for establishing the effects of treatment. Neuroimage. 2013 Aug 1;76:428-35. doi: 10.1016/j.neuroimage.2012.10.011. Review.