Buchmann, Ilka
E-Mail-Adresse
ORCID
Geburtsdatum
Berufsbeschreibung
Nachname
Vorname
Name
Suchergebnisse Publikationen
100 years after Liepmann : Lesion correlates of diminished selection and application of familiar versus novel tools
100 years ago, Liepmann highlighted the role of left ventro-dorsal lesions for impairments in conceptual (rather ventral) and motor (more dorsal) related aspects of apraxia. Many studies thereafter attributed to an extended left fronto-temporo-parietal network. Yet, to date there are only few studies that looked at apraxic performance in the selection and application of familiar versus novel tools.
In the current study we applied modern voxel-based lesion-symptom mapping (VLSM) to analyze neural correlates of impaired selection and application of familiar versus novel tools. 58 left (LBD) and 51 right brain damaged (RBD) stroke patients participated in the Novel Tools Test (NTT) and the Familiar Tools Test (FTT) of the Diagnostic Instrument for Limb Apraxia (DILA-S). We further assessed performance in control tasks, namely semantic knowledge (BOSU), visuo-spatial working memory (Corsi Block Tapping) and meaningless imitation of gestures (IML).
Impaired tool use was most pronounced after LBD. Our VLSM results in the LBD-group suggested that selection versus application-related aspects of praxis and semantics of familiar versus novel tool use can be behaviorally and neuro-anatomically differentiated. For impairments in familiar tool tasks, the major focus of lesion maps was rather ventral while deficiencies in novel tool tasks went along with rather dorsal lesions. Affected selection processes were linked to rather anterior lesions, while impacted application processes went along with rather posterior lesion maps. In our study, particular tool selection processes were rather specific for familiar versus novel tools. Foci for lesion overlaps of experimental and control tasks were noticed ventrally for semantic knowledge and FTT, in fronto-parietal regions for working memory and NTT, and ventro-dorsally for imitation of meaningless gestures and the application of NTT and FTT.
We visualized our current interpretation within a neuroanatomical model for apraxia of tool use.
Naturalistic Action Therapy : Manual
The Naturalistic Action Therapy approach was designed to train patients with impaired real tool-use and related anosognosia. The manual contains a description of example tasks trained in our laboratory. In addition video-material and evaluation sheets were designed to facilitate its application. The therapy concept can and is anticipated to be adapted for miscellaneous tasks of daily living that may need to be trained in a rehabilitation institute or at home. The main neurorehabilitation principles of the Naturalistic Action Therapy are shaping, errorless learning and performance monitoring. Thus far the approach has been tested in single stroke patients. Patients with hemiparesis, aphasia or neglect can be trained with this therapy form. However, as a requirement, patients need to understand simple task instructions.
Gliedmaßenapraxie bei Patienten mit Multipler Sklerose
Gliedmaßenapraxie ist eine Störung der motorischen Kognition, die besonders häufig nach linkshemisphärischem Schlaganfall auftritt. Diese Störung ist bei Patienten mit Multipler Sklerose (MS) noch wenig untersucht. Bisherige MS-Studien indizieren, dass die Leistung in den klassischen Pantomime- und Imitationstests beeinträchtigt sein kann. Die vorliegende Studie untersuchte die Gliedmaßenapraxie bei 26 MS-Patienten und 24 Gesunden mit dem Diagnostic Instrument for Limb Apraxia – Short Version (DILA-S), das zusätzlich zu den klassischen Imitations- und Pantomimetests auch den tatsächlichen Werkzeuggebrauch untersucht. Bei 27 % der MS-Patienten wurden apraktische Symptome in jeweils einzelnen Untertests diagnostiziert. Die Symptomausprägung war jedoch gering, sodass Gruppenvergleiche keine signifikanten Unterschiede zeigten. Insgesamt legen die Studienergebnisse nahe, dass Gliedmaßenapraxie bei MS-Patienten auftreten kann, aber vermutlich selten zu einem klinisch relevanten Symptom wird.
A combined therapy for limb apraxia and related anosognosia
Left hemisphere stroke frequently leads to limb apraxia, a disorder that has been reported to impact independence in daily life and rehabilitation success. Nonetheless, there is a shortcoming in research and availability of applicable trainings. Further, to date, anosognosia for limb apraxia has largely been neglected. Therefore, we developed a Naturalistic Action Therapy that trains object selection and application with an errorless learning approach and which includes supported self-evaluation. The current study presents the results of two stroke patients participating in the training. The procedure entailed two baseline and one post-training sessions including standardized limb apraxia and anosognosia assessments as well as 18 naturalistic action tasks. The training consisted of 15 sessions during which 4-6 of the 18 naturalistic action tasks (e.g., pour water into a glass, make a phone call) were trained. Both patients showed improvement in trained and untrained tasks as well as in standardized apraxia and anosognosia assessments. Training effects appeared strongest for the trained items. The procedure is documented in detail and easy to administer and thus may have the potential to be applied by relatives. The results of this pilot-study are promising and suggest that the approach is suitable for further evaluation.
Assessing Anosognosia in Apraxia of Common Tool-Use with the VATA-NAT
In neurological patients, a lack of insight into their impairments can lead to possibly dangerous situations and non-compliance in rehabilitation therapy with worse rehabilitation outcomes as a result. This so called anosognosia is a multifaceted syndrome that can occur after brain damage affecting different neurological or cognitive functions. To our knowledge no study has investigated anosognosia for apraxia of common tool-use (CTU) so far. CTU-apraxia is a disorder frequently occurring after stroke that affects the use of familiar objects. Here, we introduce a new questionnaire to diagnose anosognosia for CTU-apraxia, the Visual Analogue Test assessing Anosognosia for Naturalistic Action Tasks (VATA-NAT). This assessment is adapted from a series of VATA-questionnaires that evaluate insight into motor (VATA-M) or language (VATA-L) impairment and take known challenges such as aphasia into account. 51 subacute stroke patients with left (LBD) or right (RBD) brain damage were investigated including patients with and without CTU-apraxia. Patients were assessed with the VATA-L, -M and -NAT before and after applying a diagnostics session for each function. Interrater reliability, composite reliability as well as convergent and divergent validity were evaluated for the VATA-NAT. Seven percent of the LBD patients with CTU-apraxia demonstrated anosognosia. After tool-use diagnostics this number increased to 20 percent. For the VATA-NAT, psychometric data revealed high interrater-reliability (τ ≥ .828), composite reliability (CR ≥ .809) and convergent validity (τ = -.626). When assessing patients with severe aphasia, the possible influence of language comprehension difficulties needs to be taken into account for interpretation. Interestingly, for all three VATA versions the retests resulted in an increased frequency of diagnosed anosognosia in the respective function despite having been confronted with the respective impairment during a diagnostic session. Future research may have to reveal which factors influence the presence or absence of anosognosia over time. Overall, close monitoring of anosognosia over the course of rehabilitation is recommended. With the VATA-NAT we hereby provide a novel assessment for anosognosia in patients with CTU-apraxia. For diagnosing anosognosia we recommend to combine this new tool with the existing VATA-M and -L subtests, particularly in patients who demonstrate severe functional deficits.
Limb apraxia profiles in different clinical samples
Objective: Limb apraxia is a motor cognitive disorder that has been mainly studied in patients with dementia or left hemisphere stroke (LHS). However, limb apraxia has also been reported in patients with right hemisphere stroke (RHS), multiple sclerosis (MS) or traumatic brain injury (TBI). This study’s aim was to report detailed praxis performance profiles in samples suffering from these different neurological disorders by use of the Diagnostic Instrument for Limb Apraxia (DILA-S).
Method: 44 LHS patients, 36 RHS patients, 27 patients with dementia, 26MS and 44 TBI patients participated. The diagnostics included the imitation of meaningless and meaningful hand gestures, pantomime of tool-use, single real tool-use as well as a multistep naturalistic action task (preparing breakfast).
Results: Apraxia occurred in all tested samples but to a varying degree and with dissimilar profiles. LHS patients demonstrated most severe deficits in pantomime, but they were also vulnerable to deficits in real tool-use. Dementia patients showed high incidence rates of apraxia in almost all subscales of the DILA-S. RHS patients demonstrated difficulties in imitation and pantomime of tool-use, but they did not show severe difficulties with real tooluse. TBI patients appeared challenged by multistep naturalistic actions. The tested MS sample did not show clinically relevant symptoms in the DILA-S.
Conclusion: Different types of patients display varying limb apraxic symptoms detectable by the DILA-S. In these limb apraxia susceptible populations, testing should be warranted as standard.