J. B. Deijen

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Extensive changes in resting-state oscillatory brain activity have recently been demonstrated using magnetoencephalography (MEG) in moderately advanced, non-demented Parkinson's disease patients relative to age-matched controls. The aim of the present study was to determine the onset and evolution of these changes over the disease course and their(More)
Although alterations in resting-state functional connectivity between brain regions have previously been reported in Parkinson's disease, the spatial organization of these changes remains largely unknown. Here, we longitudinally studied brain network topology in Parkinson's disease in relation to clinical measures of disease progression, using(More)
We set out to determine whether changes in resting-state cortico-cortical functional connectivity are a feature of early-stage Parkinson's disease (PD), explore how functional coupling might evolve over the course of the disease and establish its relationship with clinical deficits. Whole-head magnetoencephalography was performed in an eyes-closed(More)
The present study evaluates the effects of 2 years of growth hormone (GH) replacement therapy on psychological well-being and cognitive performance in adults with childhood-onset growth hormone deficiency (CO-GHD). A total of 48 GHD adult men (mean age: 27 years) were randomly assigned to one of four treatment groups: placebo treatment, or GH replacement in(More)
Perseveration in the generation of random motor behavior was examined by means of the Vienna perseverance task in groups of de novo (n = 18) and treated (n = 18) patients with early PD, and in control subjects (n = 18). In comparison with control subjects, both the de novo and treated patients with PD were relatively unable to generate random motor(More)
The pathophysiological mechanisms of Parkinson's disease (PD)-related dementia (PDD) are still poorly understood. Previous studies using electroencephalography (EEG) and magnetoencephalography (MEG) have demonstrated widespread slowing of oscillatory brain activity as a neurophysiological characteristic of PD-related dementia. Here, we use MEG to(More)
OBJECTIVE Endocrine therapy is widely used-often for many years-in women with breast cancer. Yet little is known about cognitive functioning after long-term use of tamoxifen. We examine cognitive sequelae, approximately 3 years after diagnosis, in postmenopausal women with breast cancer who were treated with adjuvant tamoxifen. METHODS Data from(More)
Growth hormone (GH) replacement therapy with duration of several years is known to be safe and beneficial in GH-deficient adult patients. However, long-term follow-up data on GH substitution, cognition, and well-being are scarce. The purpose of this study was to investigate whether the benefits of GH replacement in psychological functioning found in(More)
OBJECTIVE To assess the ability of neurophysiologic markers in conjunction with cognitive assessment to improve prediction of progression to dementia in Parkinson disease (PD). METHODS Baseline cognitive assessments and magnetoencephalographic recordings from 63 prospectively included PD patients without dementia were analyzed in relation to PD-related(More)
OBJECTIVE To evaluate fMRI whole-brain resting-state functional connectivity changes in relation to cognitive decline in Parkinson disease (PD) over a 3-year period. METHODS Resting-state fMRI scans were acquired in 55 patients with PD (mean age 65.8 years, SD 6.37; average disease duration 9.24 years, SD 3.96) and 15 matched controls (mean age 64.4(More)