The aim of this thesis is to show the latest research results of magnetic resonance spectroscopy (MRS) and the role of MRS in schizophrenia and diffuse intrinsic pontine glioma (DIPG). 22 studies were researched, summarized and the results were described. The questions were examined, whether new insights can be obtained via MRS for schizophrenia and DIPG and to show the differences between the single-voxel technique and multi-voxel technique. The results of the studies showed a reduction of NAA value in patients with schizophrenia. A decreased Cho/Cr ratio in the thalamus showed a correlation with negative symptoms. A change in the Cho/NAA ratio in DIPG could be directly linked to the
risk of mortality. There are differences between the SVS and MRSI, however, both techniques are better suited for certain indications. The SVS is recommended for a global measurement of metabolites before and after a therapy. The MRSI is recommended for the planing and monitoring of aimed therapies. The MRS is suitable to represent changes of metabolites non-invasively in schizophrenia and in the DIPG. Additional findings to the diseases were obtained, which can improve their understanding. Also, new therapeutic approaches could be developed.