Clinical Research Directory

Optimistic and Pessimistic Dopamine Signals in the Human Brain: a Mapping and Modelling Study in Health and Parkinson's Disease

The goal of this observational study is to investigate whether the healthy human brain shows a diversity of optimistic and pessimistic reward signals and whether changes in this distribution in Parkinson's disease (PD) can provide mechanistic insights into the cause of symptoms. The main hypotheses it aims to test are: 1. As shown in mice, a diversity of optimistic and pessimistic dopamine reward signals exists in the human ventral tegmental area (VTA) and the ventro-rostral basal ganglia circuit. 2. Pessimistic neurons are more severely affected by neurodegeneration in PD. Researchers will compare the diversity of optimistic and pessimistic dopamine reward signals in patients with PD and healthy participants to see if there is a skewed distribution of optimistic and pessimistic reward signals in PD. Participants will play a task probing reward- and movement related brain activity in an MRI scanner. Researchers will derive functional topographic maps of optimism/pessimism in VTA, substantia nigra pars compacta (SNc), striatum and cortical areas such as the anterior cingulate cortex (ACC). In sub-study 1, participants will be tested on one study day where patients with PD are tested in the off-medication state (40 control participants, 40 patients with PD). In sub-study 2, to test whether/how dopaminergic medication affects the distribution of optimism/pessimism, participants will be tested on two study days (30 control participants, 30 patients with PD). Patients with PD are tested one day in the off-medication state, another day in the on-medication state (order counterbalanced between patients with PD). Control participants are tested on two days without medication challenge to test for test-retest effects.

The Use of Virtual Reality Technology During Oocyte Retrieval for in Vitro Fertilization

Ultrasound-guided oocyte retrieval (OR) is a short, but oftentimes painful procedure, during which the follicles are punctured trans-vaginally to obtain oocytes for in vitro fertilization (IVF). Conscious sedation is the most commonly used method of pain relief, yet several studies have shown that more than half of women report moderate to high levels of pain and up to 7% of women report extreme or unacceptable levels of pain during OR. Adjuvant virtual reality (VR) therapy has been explored to reduce psychological stress during dental procedures, burn wound care, colonoscopy, as well as other minor procedures. Hence, the purpose of this study is to evaluate the use of VR technology during IVF treatment, particularly with respect to tolerability, patient satisfaction, and pain reduction during oocyte retrieval.