With this study, the investigators want to examine whether receptors (docking points on the surface of a nerve cell) that bind an important messenger substance in the brain (glutamate) are increased in patients with amyotrophic lateral sclerosis (ALS) as the disease progresses. Based on observations from ALS models, the investigators suspect that this increase in receptors contributes to the damage to the nerve cells in ALS.~To image these receptors, the investigators use a specific radioactive substance and imaging combining positron emission tomography (PET), magnetic resonance spectroscopy (MRS) and magnetic resonance imaging (MRI) of the brain and spinal cord.~The investigators will examine healthy people and ALS patients. The reason is that little is known about the receptor, even in healthy people. The investigators also do not know if and when the receptor is increasingly detectable in the course of the ALS disease. Only by comparing diseased and healthy people it can be determined if and when the receptor is built up in ALS patients. The investigators also hope to gain more information, e.g. about the distribution of receptors in the brain of healthy people compared to patients.
In ALS models, it was shown that receptors, that bind an important messenger substance (glutamate) in the brain, are increased. In this research project, the investigators want to use a specific radioactive substance to find out whether these receptors are more detectable in people with ALS than in healthy people and increase over the course of the disease.