Intensive language training enhances brain plasticity in chronic aphasia

BACKGROUND: Focal clusters of slow wave activity in the delta frequency range (1–4 Hz), as measured by magnetencephalography (MEG), are usually located in the vicinity of structural damage in the brain. Such oscillations are usually considered pathological and indicative of areas incapable of normal functioning owing to deafferentation from relevant input sources. In the present study we investigated the change in Delta Dipole Density in 28 patients with chronic aphasia (>12 months post onset) following cerebrovascular stroke of the left hemisphere before and after intensive speech and language therapy (3 hours/day over 2 weeks). RESULTS: Neuropsychologically assessed language functions improved significantly after training. Perilesional delta activity decreased after therapy in 16 of the 28 patients, while an increase was evident in 12 patients. The magnitude of change of delta activity in these areas correlated with the amount of change in language functions as measured by standardized language tests. CONCLUSIONS: These results emphasize the significance of perilesional areas in the rehabilitation of aphasia even years after the stroke, and might reflect reorganisation of the language network that provides the basis for improved language functions after intensive training

Brain regions essential for improved lexical access in an aged aphasic patient: a case report

BACKGROUND: The relationship between functional recovery after brain injury and concomitant neuroplastic changes is emphasized in recent research. In the present study we aimed to delineate brain regions essential for language performance in aphasia using functional magnetic resonance imaging and acquisition in a temporal sparse sampling procedure, which allows monitoring of overt verbal responses during scanning. CASE PRESENTATION: An 80-year old patient with chronic aphasia (2 years post-onset) was investigated before and after intensive language training using an overt picture naming task. Differential brain activation in the right inferior frontal gyrus for correct word retrieval and errors was found. Improved language performance following therapy was mirrored by increased fronto-thalamic activation while stability in more general measures of attention/concentration and working memory was assured. Three healthy age-matched control subjects did not show behavioral changes or increased activation when tested repeatedly within the same 2-week time interval. CONCLUSION: The results bear significance in that the changes in brain activation reported can unequivocally be attributed to the short-term training program and a language domain-specific plasticity process. Moreover, it further challenges the claim of a limited recovery potential in chronic aphasia, even at very old age. Delineation of brain regions essential for performance on a single case basis might have major implications for treatment using transcranial magnetic stimulation

Model-orientated Aphasia Therapy and Aachen Language Analysis: Evaluation on patients with chronic aphasia

The proof of the effectiveness of aphasia therapy gains more and more in importance in light of the present financial situation of the public health system and the increasing demand for evidence based medicine. In this context it is expected that improvements are measured not only by means of standardised tests or questionnaires but also in communicational situations similar to those in everyday life. The aim of this study was to evaluate the general efficiency as well as the effective elements of the Model-Orientated Aphasia Therapy (MOAT). The therapy was conducted as a highly intensive training (3 hours/day over 10 days) on patients suffering from chronic aphasia.In order to evaluate the effective elements of the therapy, MOAT was compared with another form of aphasia therapy which has the same intensity but which is based on different principles (Constraint Induced Aphasia Therapy, CIAT).A further aim was the evaluation of the Aachen Language Analysis (Aachener Sprachanalyse, ASPA). This new spontaneous speech analysis system covers many parameters and was evaluated with regard to its objectivity, reliability and validity.Methods: MOAT is a therapy based on a model-based approach (here based on the Logogen Model ), extended by other approaches of aphasia therapy (linguistic approach, strategy approach, communicational approach and the involvement of relatives). The combination of the different therapy approaches allows a specific treatment considering the individual symptoms of patients in all disturbed levels of aphasia.The effects of MOAT were evaluated directly after therapy and again after 6 months. To gather information about possible factors responsible for treatment effects, the 12 patients treated with MOAT were compared to 12 patients belonging to the group CIATorig and 15 patients belonging to CIATnew. The Aachen Aphasia Test, questionnaires about everyday communication and a naming task served as dependent variables.In terms of ASPA the interraterreliability and the intraraterreliability for the transcript and the division into phrases were evaluated. A comparison of the two pre-therapy measurements was conducted in order to test the reliability of the results. The validity of ASPA was tested by evaluating its ability to differentiate between patients with aphasia and a healthy control group and the sensitivity when evaluating therapy effects.Results: When tested directly after therapy patients treated with MOAT showed significant improvements in the Aachen Aphasia Test and in the questionnaires about everyday communication. The results remained stable over a 6 month follow-up period. Comparing the groups MOAT, CIATorig and CIATneu across measurements, treatment effects were comparable, except for written language and questionnaires about speech perception (there were significantly better effects for MOAT than for CIATorig). Only patients treated with MOAT showed significant improvements for untrained items in the naming task.Interraterreliability and intraraterreliability of ASPA were >93%. Patients and controls did not differ significantly within the two pre-measures, except for one parameter. High correlations between the two pre-tests were obtained, mainly within the group of patients. The cluster syntax and word retrieval differed significantly between patients with aphasia and the healthy controls, whereas no differences could be found in the prosodic parameters. Significant improvements after therapy were obtained in the parameters complete phrases%, complex sentences% and complete sentences%. These results were correlated with results of the sentence production tasks of the Aachen Aphasie Test before and after therapy.Conclusions: The efficiency of MOAT and the long-term stability of improved language functions were demonstrated by means of the Aachener Aphasie Test and questionnaires about everyday communication. Based on these results the use of MOAT in the rehabilitation of patients with chronic aphasia is recommended. Comparing the three forms of therapy indicates that intensity and shaping are important factors contributing to the success of therapy. The present results recommend training patients with aphasia more intensively and under consideration of an individual therapy including written language, everyday communication and involvement of relatives.The results of the ASPA evaluation provide evidence for high objectivity and reliability. Since the prosody cluster could not distinguish significantly between patients with aphasia and healthy controls, these parameter should only used with caution in the diagnosis of aphasia. In terms of the evaluation of therapy effects, the syntactical parameter complete phrases%, complex sentences % and complete sentences% demonstrated high sensitivity