@article{ZellerDangWeiseetal.2012,
  author    = {Zeller, Daniel and Dang, Su-Yin and Weise, David and Rieckmann, Peter and Toyka, Klaus V. and Classen, Joseph},
  title     = {Excitability decreasing central motor plasticity is retained in multiple sclerosis patients},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-76333},
  year      = {2012},
  abstract  = {Background: Compensation of brain injury in multiple sclerosis (MS) may in part work through mechanisms involving neuronal plasticity on local and interregional scales. Mechanisms limiting excessive neuronal activity may have special significance for retention and (re-)acquisition of lost motor skills in brain injury. However, previous neurophysiological studies of plasticity in MS have investigated only excitability enhancing plasticity and results from neuroimaging are ambiguous. Thus, the aim of this study was to probe long-term depression-like central motor plasticity utilizing continuous theta-burst stimulation (cTBS), a non-invasive brain stimulation protocol. Because cTBS also may trigger behavioral effects through local interference with neuronal circuits, this approach also permitted investigating the functional role of the primary motor cortex (M1) in force control in patients with MS. Methods: We used cTBS and force recordings to examine long-term depression-like central motor plasticity and behavioral consequences of a M1 lesion in 14 patients with stable mild-to-moderate MS (median EDSS 1.5, range 0 to 3.5) and 14 age-matched healthy controls. cTBS consisted of bursts (50 Hz) of three subthreshold biphasic magnetic stimuli repeated at 5 Hz for 40 s over the hand area of the left M1. Corticospinal excitability was probed via motor-evoked potentials (MEP) in the abductor pollicis brevis muscle over M1 before and after cTBS. Force production performance was assessed in an isometric right thumb abduction task by recording the number of hits into a predefined force window. Results: cTBS reduced MEP amplitudes in the contralateral abductor pollicis brevis muscle to a comparable extent in control subjects (69 ± 22\% of baseline amplitude, p < 0.001) and in MS patients (69 ± 18\%, p < 0.001). In contrast, postcTBS force production performance was only impaired in controls (2.2 ± 2.8, p = 0.011), but not in MS patients (2.0 ± 4.4, p = 0.108). The decline in force production performance following cTBS correlated with corticomuscular latencies (CML) in MS patients, but did not correlate with MEP amplitude reduction in patients or controls. Conclusions: Long-term depression-like plasticity remains largely intact in mild-to-moderate MS. Increasing brain injury may render the neuronal networks less responsive toward lesion-induction by cTBS.},
  subject      = {Medizin},
  language  = {en}
}
@article{UeceylerKahnKrameretal.2013,
  author    = {{\"U}{\c{c}}eyler, Nurcan and Kahn, Ann-Kathrin and Kramer, Daniela and Zeller, Daniel and Casanova-Molla, Jordi and Wanner, Christoph and Weidemann, Frank and Katsarava, Zaza and Sommer, Claudia},
  title     = {Impaired small fiber conduction in patients with Fabry disease: a neurophysiological case-control study},
  series = {BMC Neurology},
  journal   = {BMC Neurology},
  doi       = {10.1186/1471-2377-13-47},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96527},
  year      = {2013},
  abstract  = {Background Fabry disease is an inborn lysosomal storage disorder which is associated with small fiber neuropathy. We set out to investigate small fiber conduction in Fabry patients using pain-related evoked potentials (PREP). Methods In this case-control study we prospectively studied 76 consecutive Fabry patients for electrical small fiber conduction in correlation with small fiber function and morphology. Data were compared with healthy controls using non-parametric statistical tests. All patients underwent neurological examination and were investigated with pain and depression questionnaires. Small fiber function (quantitative sensory testing, QST), morphology (skin punch biopsy), and electrical conduction (PREP) were assessed and correlated. Patients were stratified for gender and disease severity as reflected by renal function. Results All Fabry patients (31 men, 45 women) had small fiber neuropathy. Men with Fabry disease showed impaired cold (p < 0.01) and warm perception (p < 0.05), while women did not differ from controls. Intraepidermal nerve fiber density (IENFD) was reduced at the lower leg (p < 0.001) and the back (p < 0.05) mainly of men with impaired renal function. When investigating A-delta fiber conduction with PREP, men but not women with Fabry disease had lower amplitudes upon stimulation at face (p < 0.01), hands (p < 0.05), and feet (p < 0.01) compared to controls. PREP amplitudes further decreased with advance in disease severity. PREP amplitudes and warm (p < 0.05) and cold detection thresholds (p < 0.01) at the feet correlated positively in male patients. Conclusion Small fiber conduction is impaired in men with Fabry disease and worsens with advanced disease severity. PREP are well-suited to measure A-delta fiber conduction.},
  language  = {en}
}
@article{HansenKahnZelleretal.2015,
  author    = {Hansen, Niels and Kahn, Ann-Kathrin and Zeller, Daniel and Katsarava, Zaza and Sommer, Claudia and {\"U}{\c{c}}eyler, Nurcan},
  title     = {Amplitudes of pain-related evoked potentials are useful to detect small fiber involvement in painful mixed fiber neuropathies in addition to quantitative sensory testing - an electrophysiological study},
  series = {Frontiers in Neurology},
  volume    = {6},
  journal   = {Frontiers in Neurology},
  doi       = {10.3389/fneur.2015.00244},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-124824},
  pages     = {244},
  year      = {2015},
  abstract  = {To investigate the usefulness of pain-related evoked potentials (PREP) elicited by electrical stimulation for the identification of small fiber involvement in patients with mixed fiber neuropathy (MFN). Eleven MFN patients with clinical signs of large fiber impairment and neuropathic pain and ten healthy controls underwent clinical and electrophysiological evaluation. Small fiber function, electrical conductivity and morphology were examined by quantitative sensory testing (QST), PREP, and skin punch biopsy. MFN was diagnosed following clinical and electrophysiological examination (chronic inflammatory demyelinating neuropathy: n = 6; vasculitic neuropathy: n = 3; chronic axonal ­neuropathy: n = 2). The majority of patients with MFN characterized their pain by descriptors that mainly represent C-fiber-mediated pain. In QST, patients displayed elevated cold, warm, mechanical, and vibration detection thresholds and cold pain thresholds indicative of MFN. PREP amplitudes in patients correlated with cold (p < 0.05) and warm detection thresholds (p < 0.05). Burning pain and the presence of par-/dysesthesias correlated negatively with PREP amplitudes (p < 0.05). PREP amplitudes correlating with cold and warm detection thresholds, burning pain, and par-/dysesthesias support employing PREP amplitudes as an additional tool in conjunction with QST for detecting small fiber impairment in patients with MFN.},
  language  = {en}
}
@article{ZellerHeidemeierGrigoleitetal.2017,
  author    = {Zeller, Daniel and Heidemeier, Anke and Grigoleit, G{\"o}tz Ulrich and M{\"u}llges, Wolfgang},
  title     = {Case report: subacute tetraplegia in an immunocompromised patient},
  series = {BMC Neurology},
  volume    = {17},
  journal   = {BMC Neurology},
  number    = {31},
  doi       = {10.1186/s12883-017-0814-5},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-157576},
  year      = {2017},
  abstract  = {Background: Clinical reasoning in Neurology is based on general associations which help to deduce the site of the lesion. However, even "golden principles" may occasionally be deceptive. Here, we describe the case of subacute flaccid tetraparesis due to motor cortical lesions. To our knowledge, this is the first report to include an impressive illustration of nearly symmetric motor cortical involvement of encephalitis on brain MRI. Case presentation: A 51 year old immunocompromized man developed a high-grade pure motor flaccid tetraparesis over few days. Based on clinical presentation, critical illness polyneuromyopathy was suspected. However, brain MRI revealed symmetrical hyperintensities strictly limited to the subcortical precentral gyrus. An encephalitis, possibly due to CMV infection, turned out to be the most likely cause. Conclusion: While recognition of basic clinical patterns is indispensable in neurological reasoning, awareness of central conditions mimicking peripheral nervous disease may be crucial to detect unsuspected, potentially treatable conditions.},
  language  = {en}
}
@article{OdorferWindZeller2019,
  author    = {Odorfer, Thorsten M. and Wind, Teresa and Zeller, Daniel},
  title     = {Temporal discrimination thresholds and proprioceptive performance: impact of age and nerve conduction},
  series = {Frontiers in Neuroscience},
  volume    = {13},
  journal   = {Frontiers in Neuroscience},
  number    = {1241},
  issn      = {1662-453X},
  doi       = {10.3389/fnins.2019.01241},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-195648},
  year      = {2019},
  abstract  = {Background Increasing attention is payed to the contribution of somatosensory processing in motor control. In particular, temporal somatosensory discrimination has been found to be altered differentially in common movement disorders. To date, there have only been speculations as to how impaired temporal discrimination and clinical motor signs may relate to each other. Prior to disentangling this relationship, potential confounders of temporal discrimination, in particular age and peripheral nerve conduction, should be assessed, and a quantifiable measure of proprioceptive performance should be established. ObjectiveTo assess the influence of age and polyneuropathy (PNP) on somatosensory temporal discrimination threshold (STDT), temporal discrimination movement threshold (TDMT), and behavioral measures of proprioception of upper and lower limbs. Methods STDT and TDMT were assessed in 79 subjects (54 healthy, 25 with PNP; age 30-79 years). STDT was tested with surface electrodes over the thenar or dorsal foot region. TDMT was probed with needle electrodes in flexor carpi radialis (FCR) and tibialis anterior (TA) muscle. Goniometer-based devices were used to assess limb proprioception during (i) active pointing to LED markers, (ii) active movements in response to variable visual cues, and (iii) estimation of limb position following passive movements. Pointing (or estimation) error was taken as a measure of proprioceptive performance. Results In healthy subjects, higher age was associated with higher STDT and TDMT at upper and lower extremities, while age did not correlate with proprioceptive performance. Patients with PNP showed higher STDT and TDMT values and decreased proprioceptive performance in active pointing tasks compared to matched healthy subjects. As an additional finding, there was a significant correlation between performance in active pointing tasks and temporal discrimination thresholds. Conclusion Given their notable impact on measures of temporal discrimination, age and peripheral nerve conduction need to be accounted for if STDT and TDMT are applied in patients with movement disorders. As a side observation, the correlation between measures of proprioception and temporal discrimination may prompt further studies on the presumptive link between these two domains.},
  language  = {en}
}
@article{OdorferHomolaReichetal.2019,
  author    = {Odorfer, Thorsten M. and Homola, Gy{\"o}rgy A. and Reich, Martin M. and Volkmann, Jens and Zeller, Daniel},
  title     = {Increased finger-tapping related cerebellar activation in cervical dystonia, enhanced by transcranial stimulation: an indicator of compensation?},
  series = {Frontiers in Neurology},
  volume    = {10},
  journal   = {Frontiers in Neurology},
  number    = {231},
  issn      = {1664-2295},
  doi       = {10.3389/fneur.2019.00231},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-196249},
  year      = {2019},
  abstract  = {Background: Cervical dystonia is a movement disorder causing abnormal postures and movements of the head. While the exact pathophysiology of cervical dystonia has not yet been fully elucidated, a growing body of evidence points to the cerebellum as an important node. Methods: Here, we examined the impact of cerebellar interference by transcranial magnetic stimulation on finger-tapping related brain activation and neurophysiological measures of cortical excitability and inhibition in cervical dystonia and controls. Bilateral continuous theta-burst stimulation was used to modulate cerebellar cortical excitability in 16 patients and matched healthy controls. In a functional magnetic resonance imaging arm, data were acquired during simple finger tapping before and after cerebellar stimulation. In a neurophysiological arm, assessment comprised motor-evoked potentials amplitude and cortical silent period duration. Theta-burst stimulation over the dorsal premotor cortex and sham stimulation (neurophysiological arm only) served as control conditions. Results: At baseline, finger tapping was associated with increased activation in the ipsilateral cerebellum in patients compared to controls. Following cerebellar theta-burst stimulation, this pattern was even more pronounced, along with an additional movement-related activation in the contralateral somatosensory region and angular gyrus. Baseline motor-evoked potential amplitudes were higher and cortical silent period duration shorter in patients compared to controls. After cerebellar theta-burst stimulation, cortical silent period duration increased significantly in dystonia patients. Conclusion: We conclude that in cervical dystonia, finger movements—though clinically non-dystonic—are associated with increased activation of the lateral cerebellum, possibly pointing to general motor disorganization, which remains subclinical in most body regions. Enhancement of this activation together with an increase of silent period duration by cerebellar continuous theta-burst stimulation may indicate predominant disinhibitory effects on Purkinje cells, eventually resulting in an inhibition of cerebello-thalamocortical circuits.},
  language  = {en}
}
@article{NguemeniHomolaNakchbandietal.2020,
  author    = {Nguemeni, Carine and Homola, Gy{\"o}rgy A. and Nakchbandi, Luis and Pham, Mirko and Volkmann, Jens and Zeller, Daniel},
  title     = {A Single Session of Anodal Cerebellar Transcranial Direct Current Stimulation Does Not Induce Facilitation of Locomotor Consolidation in Patients With Multiple Sclerosis},
  series = {Frontiers in Human Neuroscience},
  volume    = {14},
  journal   = {Frontiers in Human Neuroscience},
  issn      = {1662-5161},
  doi       = {10.3389/fnhum.2020.588671},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-215291},
  year      = {2020},
  abstract  = {Background: Multiple sclerosis (MS) may cause variable functional impairment. The discrepancy between functional impairment and brain imaging findings in patients with MS (PwMS) might be attributed to differential adaptive and consolidation capacities. Modulating those abilities could contribute to a favorable clinical course of the disease. Objectives: We examined the effect of cerebellar transcranial direct current stimulation (c-tDCS) on locomotor adaptation and consolidation in PwMS using a split-belt treadmill (SBT) paradigm. Methods: 40 PwMS and 30 matched healthy controls performed a locomotor adaptation task on a SBT. First, we assessed locomotor adaptation in PwMS. In a second investigation, this training was followed by cerebellar anodal tDCS applied immediately after the task ipsilateral to the fast leg (T0). The SBT paradigm was repeated 24 h (T1) and 78 h (T2) post-stimulation to evaluate consolidation. Results: The gait dynamics and adaptation on the SBT were comparable between PwMS and controls. We found no effects of offline cerebellar anodal tDCS on locomotor adaptation and consolidation. Participants who received the active stimulation showed the same retention index than sham-stimulated subjects at T1 (p = 0.33) and T2 (p = 0.46). Conclusion: Locomotor adaptation is preserved in people with mild-to-moderate MS. However, cerebellar anodal tDCS applied immediately post-training does not further enhance this ability. Future studies should define the neurobiological substrates of maintained plasticity in PwMS and how these substrates can be manipulated to improve compensation. Systematic assessments of methodological variables for cerebellar tDCS are urgently needed to increase the consistency and replicability of the results across experiments in various settings.},
  language  = {en}
}
@article{PeterkaOdorferSchwabetal.2020,
  author    = {Peterka, Manuel and Odorfer, Thorsten and Schwab, Michael and Volkmann, Jens and Zeller, Daniel},
  title     = {LSVT-BIG therapy in Parkinson's disease: physiological evidence for proprioceptive recalibration},
  series = {BMC Neurology},
  volume    = {20},
  journal   = {BMC Neurology},
  doi       = {10.1186/s12883-020-01858-2},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230084},
  year      = {2020},
  abstract  = {Background There is growing evidence for proprioceptive dysfunction in patients with Parkinson's disease (PD). The Lee Silvermann Voice Treatment-BIG therapy (LSVT-BIG), a special training program aiming at an increase of movement amplitudes in persons with PD (PwPD), has shown to be effective on motor symptoms. LSVT-BIG is conceptionally based on improving bradykinesia, in particular the decrement of repetitive movements, by proprioceptive recalibration. Objective To assess proprioceptive impairment in PwPD as compared to matched controls and to probe potential recalibration effects of the LSVT-BIG therapy on proprioception. Methods Proprioceptive performance and fine motor skills were assessed in 30 PwPD and 15 matched controls. Measurements with significant impairment in PwPD were chosen as outcome parameters for a standardized 4 weeks amplitude-based training intervention (LSVT-BIG) in 11 PwPD. Proprioceptive performance served as primary outcome measure. Secondary outcome measures included the motor part of the MDS-UPDRS, the nine-hole-peg test, and a questionnaire on quality of life. Post-interventional assessments were conducted at weeks 4 and 8. Results Compared to the control group, PwPD showed significantly larger pointing errors. After 4 weeks of LSVT-BIG therapy and even more so after an additional 4 weeks of continued training, proprioceptive performance improved significantly. In addition, quality of life improved as indicated by a questionnaire. Conclusion LSVT-BIG training may achieve a recalibration of proprioceptive processing in PwPD. Our data indicates a probable physiological mechanism of a symptom-specific, amplitude-based behavioral intervention in PwPD.},
  language  = {en}
}
@article{NguemeniHiewKoegleretal.2021,
  author    = {Nguemeni, Carine and Hiew, Shawn and K{\"o}gler, Stefanie and Homola, Gy{\"o}rgy A. and Volkmann, Jens and Zeller, Daniel},
  title     = {Split-belt training but not cerebellar anodal tDCS improves stability control and reduces risk of fall in patients with multiple sclerosis},
  series = {Brain Sciences},
  volume    = {12},
  journal   = {Brain Sciences},
  number    = {1},
  issn      = {2076-3425},
  doi       = {10.3390/brainsci12010063},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-252179},
  year      = {2021},
  abstract  = {The objective of this study was to examine the therapeutic potential of multiple sessions of training on a split-belt treadmill (SBT) combined with cerebellar anodal transcranial direct current stimulation (tDCS) on gait and balance in People with Multiple Sclerosis (PwMS). Twenty-two PwMS received six sessions of anodal (PwMS\(_{real}\), n = 12) or sham (PwMS\(_{sham}\), n = 10) tDCS to the cerebellum prior to performing the locomotor adaptation task on the SBT. To evaluate the effect of the intervention, functional gait assessment (FGA) scores and distance walked in 2 min (2MWT) were measured at the baseline (T0), day 6 (T5), and at the 4-week follow up (T6). Locomotor performance and changes of motor outcomes were similar in PwMS\(_{real}\) and PwMS\(_{sham}\) independently from tDCS mode applied to the cerebellum (anodal vs. sham, on FGA, p = 0.23; and 2MWT, p = 0.49). When the data were pooled across the groups to investigate the effects of multiple sessions of SBT training alone, significant improvement of gait and balance was found on T5 and T6, respectively, relative to baseline (FGA, p < 0.001 for both time points). The FGA change at T6 was significantly higher than at T5 (p = 0.01) underlining a long-lasting improvement. An improvement of the distance walked during the 2MWT was also observed on T5 and T6 relative to T0 (p = 0.002). Multiple sessions of SBT training resulted in a lasting improvement of gait stability and endurance, thus potentially reducing the risk of fall as measured by FGA and 2MWT. Application of cerebellar tDCS during SBT walking had no additional effect on locomotor outcomes.},
  language  = {en}
}
@article{SchischlevskijCordtsGuentheretal.2021,
  author    = {Schischlevskij, Pavel and Cordts, Isabell and G{\"u}nther, Ren{\´e} and Stolte, Benjamin and Zeller, Daniel and Schr{\"o}ter, Carsten and Weyen, Ute and Regensburger, Martin and Wolf, Joachim and Schneider, Ilka and Hermann, Andreas and Metelmann, Moritz and Kohl, Zacharias and Linker, Ralf A. and Koch, Jan Christoph and Stendel, Claudia and M{\"u}schen, Lars H. and Osmanovic, Alma and Binz, Camilla and Klopstock, Thomas and Dorst, Johannes and Ludolph, Albert C. and Boentert, Matthias and Hagenacker, Tim and Deschauer, Marcus and Lingor, Paul and Petri, Susanne and Schreiber-Katz, Olivia},
  title     = {Informal caregiving in amyotrophic lateral sclerosis (ALS): a high caregiver burden and drastic consequences on caregivers' lives},
  series = {Brain Sciences},
  volume    = {11},
  journal   = {Brain Sciences},
  number    = {6},
  issn      = {2076-3425},
  doi       = {10.3390/brainsci11060748},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-240981},
  year      = {2021},
  abstract  = {Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that causes progressive autonomy loss and need for care. This does not only affect patients themselves, but also the patients' informal caregivers (CGs) in their health, personal and professional lives. The big efforts of this multi-center study were not only to evaluate the caregivers' burden and to identify its predictors, but it also should provide a specific understanding of the needs of ALS patients' CGs and fill the gap of knowledge on their personal and work lives. Using standardized questionnaires, primary data from patients and their main informal CGs (n = 249) were collected. Patients' functional status and disease severity were evaluated using the Barthel Index, the revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) and the King's Stages for ALS. The caregivers' burden was recorded by the Zarit Burden Interview (ZBI). Comorbid anxiety and depression of caregivers were assessed by the Hospital Anxiety and Depression Scale. Additionally, the EuroQol Five Dimension Five Level Scale evaluated their health-related quality of life. The caregivers' burden was high (mean ZBI = 26/88, 0 = no burden, ≥24 = highly burdened) and correlated with patients' functional status (r\(_p\) = -0.555, p < 0.001, n = 242). It was influenced by the CGs' own mental health issues due to caregiving (+11.36, 95\% CI [6.84; 15.87], p < 0.001), patients' wheelchair dependency (+9.30, 95\% CI [5.94; 12.66], p < 0.001) and was interrelated with the CGs' depression (r\(_p\) = 0.627, p < 0.001, n = 234), anxiety (r\(_p\) = 0.550, p < 0.001, n = 234), and poorer physical condition (r\(_p\) = -0.362, p < 0.001, n = 237). Moreover, female CGs showed symptoms of anxiety more often, which also correlated with the patients' impairment in daily routine (r\(_s\) = -0.280, p < 0.001, n = 169). As increasing disease severity, along with decreasing autonomy, was the main predictor of caregiver burden and showed to create relevant (negative) implications on CGs' lives, patient care and supportive therapies should address this issue. Moreover, in order to preserve the mental and physical health of the CGs, new concepts of care have to focus on both, on not only patients but also their CGs and gender-associated specific issues. As caregiving in ALS also significantly influences the socioeconomic status by restrictions in CGs' work lives and income, and the main reported needs being lack of psychological support and a high bureaucracy, the situation of CGs needs more attention. Apart from their own multi-disciplinary medical and psychological care, more support in care and patient management issues is required.},
  language  = {en}
}
@article{PeseschkianCordtsGuentheretal.2021,
  author    = {Peseschkian, Tara and Cordts, Isabell and G{\"u}nther, Ren{\´e} and Stolte, Benjamin and Zeller, Daniel and Schr{\"o}ter, Carsten and Weyen, Ute and Regensburger, Martin and Wolf, Joachim and Schneider, Ilka and Hermann, Andreas and Metelmann, Moritz and Kohl, Zacharias and Linker, Ralf A. and Koch, Jan Christoph and B{\"u}chner, Boriana and Weiland, Ulrike and Sch{\"o}nfelder, Erik and Heinrich, Felix and Osmanovic, Alma and Klopstock, Thomas and Dorst, Johannes and Ludolph, Albert C. and Boentert, Matthias and Hagenacker, Tim and Deschauer, Marcus and Lingor, Paul and Petri, Susanne and Schreiber-Katz, Olivia},
  title     = {A nation-wide, multi-center study on the quality of life of ALS patients in Germany},
  series = {Brain Sciences},
  volume    = {11},
  journal   = {Brain Sciences},
  number    = {3},
  issn      = {2076-3425},
  doi       = {10.3390/brainsci11030372},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-234147},
  year      = {2021},
  abstract  = {Improving quality of life (QoL) is central to amyotrophic lateral sclerosis (ALS) treatment. This Germany-wide, multicenter cross-sectional study analyses the impact of different symptom-specific treatments and ALS variants on QoL. Health-related QoL (HRQoL) in 325 ALS patients was assessed using the Amyotrophic Lateral Sclerosis Assessment Questionnaire 5 (ALSAQ-5) and EuroQol Five Dimension Five Level Scale (EQ-5D-5L), together with disease severity (captured by the revised ALS Functional Rating Scale (ALSFRS-R)) and the current care and therapies used by our cohort. At inclusion, the mean ALSAQ-5 total score was 56.93 (max. 100, best = 0) with a better QoL associated with a less severe disease status (β = -1.96 per increase of one point in the ALSFRS-R score, p < 0.001). "Limb-onset" ALS (lALS) was associated with a better QoL than "bulbar-onset" ALS (bALS) (mean ALSAQ-5 total score 55.46 versus 60.99, p = 0.040). Moreover, with the ALSFRS-R as a covariate, using a mobility aid (β = -7.60, p = 0.001), being tracheostomized (β = -14.80, p = 0.004) and using non-invasive ventilation (β = -5.71, p = 0.030) were associated with an improved QoL, compared to those at the same disease stage who did not use these aids. In contrast, antidepressant intake (β = 5.95, p = 0.007), and increasing age (β = 0.18, p = 0.023) were predictors of worse QoL. Our results showed that the ALSAQ-5 was better-suited for ALS patients than the EQ-5D-5L. Further, the early and symptom-specific clinical management and supply of assistive devices can significantly improve the individual HRQoL of ALS patients. Appropriate QoL questionnaires are needed to monitor the impact of treatment to provide the best possible and individualized care.},
  language  = {en}
}
@article{NguemeniStiehlHiewetal.2021,
  author    = {Nguemeni, Carine and Stiehl, Annika and Hiew, Shawn and Zeller, Daniel},
  title     = {No Impact of Cerebellar Anodal Transcranial Direct Current Stimulation at Three Different Timings on Motor Learning in a Sequential Finger-Tapping Task},
  series = {Frontiers in Human Neuroscience},
  volume    = {15},
  journal   = {Frontiers in Human Neuroscience},
  issn      = {1662-5161},
  doi       = {10.3389/fnhum.2021.631517},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225477},
  year      = {2021},
  abstract  = {Background: Recently, attention has grown toward cerebellar neuromodulation in motor learning using transcranial direct current stimulation (tDCS). An important point of discussion regarding this modulation is the optimal timing of tDCS, as this parameter could significantly influence the outcome. Hence, this study aimed to investigate the effects of the timing of cerebellar anodal tDCS (ca-tDCS) on motor learning using a sequential finger-tapping task (FTT). Methods: One hundred and twenty two healthy young, right-handed subjects (96 females) were randomized into four groups (During\(_{sham}\), Before, During\(_{real}\), After). They performed 2 days of FTT with their non-dominant hand on a custom keyboard. The task consisted of 40 s of typing followed by 20 s rest. Each participant received ca-tDCS (2 mA, sponge electrodes of 25 cm\(^{2}\), 20 min) at the appropriate timing and performed 20 trials on the first day (T1, 20 min). On the following day, only 10 trials of FTT were performed without tDCS (T2, 10 min). Motor skill performance and retention were assessed. Results: All participants showed a time-dependent increase in learning. Motor performance was not different between groups at the end of T1 (p = 0.59). ca-tDCS did not facilitate the retention of the motor skill in the FTT at T2 (p = 0.27). Thus, our findings indicate an absence of the effect of ca-tDCS on motor performance or retention of the FTT independently from the timing of stimulation. Conclusion: The present results suggest that the outcome of ca-tDCS is highly dependent on the task and stimulation parameters. Future studies need to establish a clear basis for the successful and reproducible clinical application of ca-tDCS.},
  language  = {en}
}
@article{HiewNguemeniZeller2022,
  author    = {Hiew, Shawn and Nguemeni, Carine and Zeller, Daniel},
  title     = {Efficacy of transcranial direct current stimulation in people with multiple sclerosis: a review},
  series = {European Journal of Neurology},
  volume    = {29},
  journal   = {European Journal of Neurology},
  number    = {2},
  doi       = {10.1111/ene.15163},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259424},
  pages     = {648-664},
  year      = {2022},
  abstract  = {Background and purpose Multiple sclerosis (MS) is a chronic inflammatory disease causing a wide range of symptoms including motor and cognitive impairment, fatigue and pain. Over the last two decades, non-invasive brain stimulation, especially transcranial direct current stimulation (tDCS), has increasingly been used to modulate brain function in various physiological and pathological conditions. However, its experimental applications for people with MS were noted only as recently as 2010 and have been growing since then. The efficacy for use in people with MS remains questionable with the results of existing studies being largely conflicting. Hence, the aim of this review is to paint a picture of the current state of tDCS in MS research grounded on studies applying tDCS that have been done to date. Methods A keyword search was performed to retrieve articles from the earliest article identified until 14 February 2021 using a combination of the groups (1) 'multiple sclerosis', 'MS' and 'encephalomyelitis' and (2) 'tDCS' and 'transcranial direct current stimulation'. Results The analysis of the 30 articles included in this review underlined inconsistent effects of tDCS on the motor symptoms of MS based on small sample sizes. However, tDCS showed promising benefits in ameliorating fatigue, pain and cognitive symptoms. Conclusion Transcranial direct current stimulation is attractive as a non-drug approach in ameliorating MS symptoms, where other treatment options remain limited. The development of protocols tailored to the individual's own neuroanatomy using high definition tDCS and the introduction of network mapping in the experimental designs might help to overcome the variability between studies.},
  language  = {en}
}
@article{WohnradeVellingMixetal.2023,
  author    = {Wohnrade, Camilla and Velling, Ann-Kathrin and Mix, Lucas and Wurster, Claudia D. and Cordts, Isabell and Stolte, Benjamin and Zeller, Daniel and Uzelac, Zeljko and Platen, Sophia and Hagenacker, Tim and Deschauer, Marcus and Lingor, Paul and Ludolph, Albert C. and Lul{\´e}, Doroth{\´e}e and Petri, Susanne and Osmanovic, Alma and Schreiber-Katz, Olivia},
  title     = {Health-related quality of life in spinal muscular atrophy patients and their caregivers — a prospective, cross-sectional, multi-center analysis},
  series = {Brain Sciences},
  volume    = {13},
  journal   = {Brain Sciences},
  number    = {1},
  issn      = {2076-3425},
  doi       = {10.3390/brainsci13010110},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-305048},
  year      = {2023},
  abstract  = {Spinal muscular atrophy (SMA) is a disabling disease that affects not only the patient's health-related quality of life (HRQoL), but also causes a high caregiver burden (CGB). The aim of this study was to evaluate HRQoL, CGB, and their predictors in SMA. In two prospective, cross-sectional, and multi-center studies, SMA patients (n = 39) and SMA patient/caregiver couples (n = 49) filled in the EuroQoL Five Dimension Five Level Scale (EQ-5D-5L) and the Short Form Health Survey 36 (SF-36). Caregivers (CGs) additionally answered the Zarit Burden Interview (ZBI) and the Hospital Anxiety and Depression Scale (HADS). Patients were clustered into two groups with either low or high HRQoL (EQ-5D-5L index value <0.259 or >0.679). The latter group was mostly composed of ambulatory type III patients with higher motor/functional scores. More severely affected patients reported low physical functioning but good mental health and vitality. The CGB (mean ZBI = 22/88) correlated negatively with patients' motor/functional scores and age. Higher CGB was associated with a lower HRQoL, higher depression and anxiety, and more health impairments of the CGs. We conclude that patient and CG well-being levels interact closely, which highlights the need to consider the health of both parties while evaluating novel treatments.},
  language  = {en}
}
@article{FriedrichSchneiderBuerkleinetal.2023,
  author    = {Friedrich, Maximilian U. and Schneider, Erich and Buerklein, Miriam and Taeger, Johannes and Hartig, Johannes and Volkmann, Jens and Peach, Robert and Zeller, Daniel},
  title     = {Smartphone video nystagmography using convolutional neural networks: ConVNG},
  series = {Journal of Neurology},
  volume    = {270},
  journal   = {Journal of Neurology},
  number    = {5},
  doi       = {10.1007/s00415-022-11493-1},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324526},
  pages     = {2518-2530},
  year      = {2023},
  abstract  = {Background Eye movement abnormalities are commonplace in neurological disorders. However, unaided eye movement assessments lack granularity. Although videooculography (VOG) improves diagnostic accuracy, resource intensiveness precludes its broad use. To bridge this care gap, we here validate a framework for smartphone video-based nystagmography capitalizing on recent computer vision advances. Methods A convolutional neural network was fine-tuned for pupil tracking using > 550 annotated frames: ConVNG. In a cross-sectional approach, slow-phase velocity of optokinetic nystagmus was calculated in 10 subjects using ConVNG and VOG. Equivalence of accuracy and precision was assessed using the "two one-sample t-test" (TOST) and Bayesian interval-null approaches. ConVNG was systematically compared to OpenFace and MediaPipe as computer vision (CV) benchmarks for gaze estimation. Results ConVNG tracking accuracy reached 9-15\% of an average pupil diameter. In a fully independent clinical video dataset, ConVNG robustly detected pupil keypoints (median prediction confidence 0.85). SPV measurement accuracy was equivalent to VOG (TOST p < 0.017; Bayes factors (BF) > 24). ConVNG, but not MediaPipe, achieved equivalence to VOG in all SPV calculations. Median precision was 0.30°/s for ConVNG, 0.7°/s for MediaPipe and 0.12°/s for VOG. ConVNG precision was significantly higher than MediaPipe in vertical planes, but both algorithms' precision was inferior to VOG. Conclusions ConVNG enables offline smartphone video nystagmography with an accuracy comparable to VOG and significantly higher precision than MediaPipe, a benchmark computer vision application for gaze estimation. This serves as a blueprint for highly accessible tools with potential to accelerate progress toward precise and personalized Medicine.},
  language  = {en}
}
@article{OdorferYabeHiewetal.2023,
  author    = {Odorfer, Thorsten M. and Yabe, Marie and Hiew, Shawn and Volkmann, Jens and Zeller, Daniel},
  title     = {Topological differences and confounders of mental rotation in cervical dystonia and blepharospasm},
  series = {Scientific Reports},
  volume    = {13},
  journal   = {Scientific Reports},
  doi       = {10.1038/s41598-023-33262-4},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-357713},
  year      = {2023},
  abstract  = {Mental rotation (mR) bases on imagination of actual movements. It remains unclear whether there is a specific pattern of mR impairment in focal dystonia. We aimed to investigate mR in patients with cervical dystonia (CD) and blepharospasm (BS) and to assess potential confounders. 23 CD patients and 23 healthy controls (HC) as well as 21 BS and 19 hemifacial spasm (HS) patients were matched for sex, age, and education level. Handedness, finger dexterity, general reaction time, and cognitive status were assessed. Disease severity was evaluated by clinical scales. During mR, photographs of body parts (head, hand, or foot) and a non-corporal object (car) were displayed at different angles rotated within their plane. Subjects were asked to judge laterality of the presented image by keystroke. Both speed and correctness were evaluated. Compared to HC, CD and HS patients performed worse in mR of hands, whereas BS group showed comparable performance. There was a significant association of prolonged mR reaction time (RT) with reduced MoCA scores and with increased RT in an unspecific reaction speed task. After exclusion of cognitively impaired patients, increased RT in the mR of hands was confined to CD group, but not HS. While the question of whether specific patterns of mR impairment reliably define a dystonic endophenotype remains elusive, our findings point to mR as a useful tool, when used carefully with control measures and tasks, which may be capable of identifying specific deficits that distinguish between subtypes of dystonia.},
  language  = {en}
}