@article{BorchersMuellerSynofziketal.2013, author = {Borchers, Svenja and M{\"u}ller, Laura and Synofzik, Matthis and Himmelbach, Marc}, title = {Guidelines and quality measures for the diagnosis of optic ataxia}, series = {Frontiers in Human Neuroscience}, volume = {7}, journal = {Frontiers in Human Neuroscience}, number = {324}, issn = {1662-5161}, doi = {10.3389/fnhum.2013.00324}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-122439}, year = {2013}, abstract = {Since the first description of a systematic mis-reaching by Balint in 1909, a reasonable number of patients showing a similar phenomenology, later termed optic ataxia (OA), has been described. However, there is surprising inconsistency regarding the behavioral measures that are used to detect OA in experimental and clinical reports, if the respective measures are reported at all. A typical screening method that was presumably used by most researchers and clinicians, reaching for a target object in the peripheral visual space, has never been evaluated. We developed a set of instructions and evaluation criteria for the scoring of a semi-standardized version of this reaching task. We tested 36 healthy participants, a group of 52 acute and chronic stroke patients, and 24 patients suffering from cerebellar ataxia. We found a high interrater reliability and a moderate test-retest reliability comparable to other clinical instruments in the stroke sample. The calculation of cut-off thresholds based on healthy control and cerebellar patient data showed an unexpected high number of false positives in these samples due to individual outliers that made a considerable number of errors in peripheral reaching. This study provides first empirical data from large control and patient groups for a screening procedure that seems to be widely used but rarely explicitly reported and prepares the grounds for its use as a standard tool for the description of patients who are included in single case or group studies addressing optic ataxia similar to the use of neglect, extinction, or apraxia screening tools.}, language = {en} } @article{AlbrechtMuellerBallarinietal.2019, author = {Albrecht, Franziska and Mueller, Karsten and Ballarini, Tommaso and Lampe, Leonie and Diehl-Schmid, Janine and Fassbender, Klaus and Fliessbach, Klaus and Jahn, Holger and Jech, Robert and Kassubek, Jan and Kornhuber, Johannes and Landwehrmeyer, Bernhard and Lauer, Martin and Ludolph, Albert C. and Lyros, Epameinondas and Prudlo, Johannes and Schneider, Anja and Synofzik, Matthis and Wiltfang, Jens and Danek, Adrian and Otto, Markus and Schroeter, Matthias L.}, title = {Unraveling corticobasal syndrome and alien limb syndrome with structural brain imaging}, series = {Cortex}, volume = {117}, journal = {Cortex}, doi = {10.1016/j.cortex.2019.02.015}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-221040}, pages = {33-40}, year = {2019}, abstract = {Alien limb phenomenon is a rare syndrome associated with a feeling of non-belonging and disowning toward one's limb. In contrast, anarchic limb phenomenon leads to involuntary but goal-directed movements. Alien/anarchic limb phenomena are frequent in corticobasal syndrome (CBS), an atypical parkinsonian syndrome characterized by rigidity, akinesia, dystonia, cortical sensory deficit, and apraxia. The structure function relationship of alien/anarchic limb was investigated in multi centric structural magnetic resonance imaging (MRI) data. Whole-group and single subject comparisons were made in 25 CBS and eight CBS-alien/anarchic limb patients versus controls. Support vector machine was used to see if CBS with and without alien/anarchic limb could be distinguished by structural MRI patterns. Whole-group comparison of CBS versus controls revealed asymmetric frontotemporal atrophy. CBS with alien/anarchic limb syndrome versus controls showed frontoparietal atrophy including the supplementary motor area contralateral to the side of the affected limb. Exploratory analysis identified frontotemporal regions encompassing the pre-/and postcentral gyrus as compromised in CBS with alien limb syndrome. Classification of CBS patients yielded accuracies of 79\%. CBS-alien/anarchic limb syndrome was differentiated from CBS patients with an accuracy of 81\%. Predictive differences were found in the cingulate gyrus spreading to frontomedian cortex, postcentral gyrus, and temporoparietoocipital regions. We present the first MRI-based group analysis on CBS-alien/anarchic limb. Results pave the way for individual clinical syndrome prediction and allow understanding the underlying neurocognitive architecture. (C) 2019 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).}, language = {en} }