Markus Frings

Bio: Markus Frings is an academic researcher from University of Duisburg-Essen. The author has contributed to research in topics: Cerebellum & Eyeblink conditioning. The author has an hindex of 19, co-authored 34 publications receiving 1402 citations.

Timing of conditioned eyeblink responses is impaired in cerebellar patients.

Abstract: In the present study, timing of conditioned eyeblink responses (CRs) was investigated in cerebellar patients and age-matched controls using a standard delay paradigm. Findings were compared with previously published data of CR incidences in the same patient population (Gerwig et al., 2003; Timmann et al., 2005). Sixteen patients with pure cortical cerebellar degeneration (spinocerebellar ataxia type 6 and idiopathic cerebellar ataxia), 14 patients with lesions within the territory of the superior cerebellar artery, and 13 patients with infarctions within the territory of the posterior inferior cerebellar artery were included. The affected cerebellar lobules and possible involvement of cerebellar nuclei were determined by three-dimensional magnetic resonance imaging (MRI) in patients with focal lesions (n = 27). Based on a voxel-by-voxel analysis, MRI lesion data were related to eyeblink conditioning data. CR incidence was significantly reduced, and CRs occurred significantly earlier in patients with cortical cerebellar degeneration and lesions of the superior cerebellum compared with controls. Incidence and timing of CRs was not impaired in patients with lesions restricted to the posterior and inferior cerebellum. Voxel-based MRI analysis revealed that cortical areas within the anterior lobe (Larsell lobule HV) were most significantly related to timing deficits, whereas reduced CR incidences were related to more caudal parts (lobule HVI) of the superior cerebellar cortex. The present data suggest that different parts of the superior cerebellar cortex may be involved in the formation of the stimulus association and appropriate timing of conditioned eyeblink responses in humans. Extracerebellar premotoneuronal disinhibition, however, is another possible explanation for changes in CR timing.

Posterior reversible encephalopathy syndrome (PRES): electroencephalographic findings and seizure patterns

Abstract: To better describe seizure type, frequency, and electroencephalographic (EEG) findings in posterior reversible encephalopathy syndrome (PRES) and correlate these data with clinical and magnetic resonance imaging (MRI) data, we retrospectively assessed medical charts and EEG studies of patients with PRES treated between 2004 and 2011 Data collected included patients’ underlying pathology, lesion distribution by MRI, seizure type and frequency, EEG pathologic background activity, focal pathology, and epileptogenic activity Thirty-eight of 49 adults with PRES suffered from seizures; 17 underwent EEG and were included in the analysis Perpetuating factors were similar to those reported in the literature In 15 of 17 patients, MRI showed widespread involvement rather than purely occipital lesions Nine patients had subcortical and cortical involvement Seizures were single short grand mal (GM) in 11, serial GM in 2, recurrent GM in 2, and additional focal seizures in 2 No seizures were noted beyond the first day After discontinuation of antiepileptic medication, no patients experienced seizure recurrence during 6-month follow-up EEG showed diffuse theta/delta slowing in 13 patients and epileptogenic activity with focal sharp-wave and periodic lateralizing epileptiform discharges in 2 patients Seizures in PRES are most commonly single GM and are usually of limited duration EEG shows variable theta/delta slowing Focal EEG pathology is seen in patients with focal seizures Seizures occur early after disease onset and terminate spontaneously or under therapy during the first 24 h Seizure recurrence beyond 24 h and chronic epilepsy were not seen Seizures in PRES are frequent but appear to be uncomplicated and do not herald worse prognosis EEG is helpful in evaluating the degree of encephalopathy and monitoring epileptic activity Long-term antiepileptic medication does not appear to be warranted

Cerebellum and Nonmotor Function

Abstract: Does the cerebellum influence nonmotor behavior? Recent anatomical studies demonstrate that the output of the cerebellum targets multiple nonmotor areas in the prefrontal and posterior parietal cortex, as well as the cortical motor areas. The projections to different cortical areas originate from distinct output channels within the cerebellar nuclei. The cerebral cortical area that is the main target of each output channel is a major source of input to the channel. Thus, a closed-loop circuit represents the major architectural unit of cerebro-cerebellar interactions. The outputs of these loops provide the cerebellum with the anatomical substrate to influence the control of movement and cognition. Neuroimaging and neuropsychological data supply compelling support for this view. The range of tasks associated with cerebellar activation is remarkable and includes tasks designed to assess attention, executive control, language, working memory, learning, pain, emotion, and addiction. These data, along with the revelations about cerebro-cerebellar circuitry, provide a new framework for exploring the contribution of the cerebellum to diverse aspects of behavior.