Cognition-Related Functional Topographies in Parkinson's Disease: Localized Loss of the Ventral Default Mode Network.

Cognitive dysfunction in Parkinson's disease (PD) is associated with increased expression of the PD cognition-related pattern (PDCP), which overlaps with the normal default mode network (DMN). Here, we sought to determine the degree to which the former network represents loss of the latter as a manifestation of the disease process. To address this, we first analyzed metabolic images (fluorodeoxyglucose positron emission tomography [PET]) from a large PD sample with varying cognitive performance.

Diplopia in Parkinson's disease: Indication of a cortical phenotype with cognitive dysfunction?

Background: Visual disturbances are increasingly recognized as common non-motor symptoms in Parkinson's disease (PD). In PD patients, intermittent diplopia has been found to be associated with the presence of visual hallucinations and the Parkinson's psychosis spectrum. Here, we investigated whether diplopia in PD is associated with other non-motor traits and cognitive impairment.

Restless legs syndrome is a relevant comorbidity in patients with inflammatory bowel disease.

Background And Aims: In patients with inflammatory bowel disease (IBD), restless legs syndrome (RLS) may occur as an extraintestinal disease manifestation. Iron deficiency (ID) or folate deficiency/vitamin B deficiency (FD/VBD) has previously been described to cause RLS. Here, we determined the prevalence and severity of RLS in IBD patients and evaluated the effect of iron and/or folic acid/vitamin B supplementation.

Characterization of diplopia in non-demented patients with Parkinson's disease.

Introduction: Although diplopia is considered a frequent symptom of Parkinson's disease (PD), little is known about its clinical manifestation, associated mechanisms and treatment. Here we characterized binocular diplopia in non-demented PD patients in an interdisciplinary setting.

Methods: PD patients were prospectively screened for diplopia, visual hallucinations, problems with spatial perception, contrast sensitivity, presence of blurred vision, and history of ophthalmological comorbidities via interview.

Impact of restless legs syndrome in patients with inflammatory bowel disease on sleep, fatigue, and quality of life.

Purpose: Inflammatory bowel disease has been associated with neurological symptoms including restless legs syndrome. Here, we investigated the impact of restless legs syndrome in patients with inflammatory bowel disease on sleep, fatigue, mood, cognition, and quality of life.

Methods: Two groups of inflammatory bowel disease patients, with and without restless legs syndrome, were prospectively evaluated for sleep disorders, fatigue, daytime sleepiness, depression, anxiety, and health-related quality of life.

The single intake of levodopa modulates implicit learning in drug naïve, de novo patients with idiopathic Parkinson's disease.

Although dopamine is known to aggravate implicit learning, the exact impact on behaviour when feedback is unavailable remains unclear. Previous studies revealed that non-rewarded learning habits are affected in long-term dopaminergic treated patients with Parkinson's disease (PD). We studied the influence of a onetime levodopa intake on implicit learning in de novo, untreated PD patients.

Somatosensory symptoms in unmedicated de novo patients with idiopathic Parkinson's disease.

Parkinson's disease (PD) is a neurodegenerative condition presenting with motor and non-motor symptoms including somatosensory disturbances. As neuropathic syndromes in advanced PD patients are supposed to be due to antiparkinsonian medication, we studied the presence of somatosensory symptoms and peripheral nerve function in drug naïve patients with PD as well as age-matched healthy controls. Somatosensory symptoms and signs were investigated in 39 de novo PD patients and 32 age-matched healthy controls using the modified Toronto Clinical Neuropathy Scale.

Dysfunctional action control as a specific feature of Parkinson's disease.

Parkinson's disease (PD) is characterised by motor deficits as well as cognitive alterations, particularly concerning frontal lobe control. Here, we were interested in whether executive function is abnormal already early in PD, as well as whether this dysfunction worsens as a part of the dementia in PD. The following groups engaged in tasks addressing action control: PD patients with mild and advanced motor symptoms (aPD) without dementia, PD patients with dementia (PDD), patients with Alzheimer's disease (AD) and healthy subjects (CON).

Neuropathy in Parkinson's disease patients with intestinal levodopa infusion versus oral drugs.

Background: Severe polyneuropathy has been observed in a number of patients treated for Parkinson's disease with Levodopa/Carbidopa intestinal gel infusion. This may reflect a rare individual complication or a systematic side effect.

Objective: To investigate whether peripheral nerve function differed between patients with oral treatment versus Levodopa/Carbidopa intestinal gel infusion.

Evaluation of a telemedical care programme for patients with Parkinson's disease.

We reviewed a telemedicine-based care model for drug optimization in Parkinson's disease. In this model patients send video recordings made in the home to the treating team via the Internet. These serve as the basis for making therapeutic decisions, in particular drug adjustments.

Abnormal distracter processing in adults with attention-deficit-hyperactivity disorder.

Background: Subjects with Attention-Deficit Hyperactivity Disorder (ADHD) are overdistractible by stimuli out of the intended focus of attention. This control deficit could be due to primarily reduced attentional capacities or, e. g.

Modulation of habit formation by levodopa in Parkinson's disease.

Dopamine promotes the execution of positively reinforced actions, but its role for the formation of behaviour when feedback is unavailable remains open. To study this issue, the performance of treated/untreated patients with Parkinson's disease and controls was analysed in an implicit learning task, hypothesising dopamine-dependent adherence to hidden task rules. Sixteen patients on/off levodopa and fourteen healthy subjects engaged in a Go/NoGo paradigm comprising four equiprobable stimuli.

Malnutritional neuropathy under intestinal levodopa infusion.

Levodopa/Carbidopa intestinal gel infusion (LCIG) for Parkinson's disease is under debate to provoke polyneuropathy (PNP). In our cohort of 20 thus treated patients, two developed debilitating axonal PNP with deficient pyridoxin and folate levels, and marginal cobalamin. Homocysteine was highly elevated.

Differential influence of levodopa on reward-based learning in Parkinson's disease.

The mesocorticolimbic dopamine (DA) system linking the dopaminergic midbrain to the prefrontal cortex and subcortical striatum has been shown to be sensitive to reinforcement in animals and humans. Within this system, coexistent segregated striato-frontal circuits have been linked to different functions. In the present study, we tested patients with Parkinson's disease (PD), a neurodegenerative disorder characterized by dopaminergic cell loss, on two reward-based learning tasks assumed to differentially involve dorsal and ventral striato-frontal circuits.

Speed effects of deep brain stimulation for Parkinson's disease.

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) accelerates reaction time (RT) in patients with Parkinson's disease (PD), particularly in tasks in which decisions on the response side have to be made. This might indicate that DBS speeds up both motor and nonmotor operations. Therefore, we studied the extent to which modifications of different processing streams could explain changes of RT under subthalamic DBS.

Thalamo-cortical processing of near-threshold somatosensory stimuli in humans.

Somatosensory stimuli elicit complex cortical responses that are discernible as somatosensory evoked potentials (SEPs) in scalp electroencephalographic recordings. Whereas earlier SEP components, occurring up to 100 ms after stimulus delivery, have been labeled 'preconscious', later responses have been associated with stimulus awareness. To date, how far these processes are primarily cortical or comprise additional subcortical operations remains open.

The human thalamus processes syntactic and semantic language violations.

Numerous linguistic operations have been assigned to cortical brain areas, but the contributions of subcortical structures to human language processing are still being discussed. Using simultaneous EEG recordings directly from deep brain structures and the scalp, we show that the human thalamus systematically reacts to syntactic and semantic parameters of auditorily presented language in a temporally interleaved manner in coordination with cortical regions. In contrast, two key structures of the basal ganglia, the globus pallidus internus and the subthalamic nucleus, were not found to be engaged in these processes.

The human thalamus is crucially involved in executive control operations.

The processing of executive control is thought to involve cortical as well as thalamic brain areas. However, the questions of how thalamic structures contribute to the control of behavior and how cortical versus thalamic processing is coordinated remain to be settled. We therefore aimed at specifying respective activations during the performance of a go/no-go task.

Task-related differential dynamics of EEG alpha- and beta-band synchronization in cortico-basal motor structures.

Movement-related processing results in the modulation of neuronal synchronization over several electroencephalography (EEG) frequency ranges, including alpha- (8-12 Hz) and beta-band (14-30 Hz). Whether modulation patterns differ across sites within the motor system remains unclear, but could denote how information is conveyed across the cortico-basal network. We therefore compared the event-related synchronization/desynchronization (ERS/ERD) in recordings from the scalp, basal ganglia and thalamic structures during a motor task.

Mental chronometry of target detection: human thalamus leads cortex.

Attentive monitoring of environmental stimuli is most fundamental for rapid target detection. The aim of this study was to assess the timing of thalamic versus cortical processes involved in this cognitive operation. To this end, simultaneous depth and scalp EEG was recorded in eight patients with essential tremor, undergoing thalamic deep brain stimulation (DBS), when the DBS electrodes could be accessed via their temporarily externalized leads.