The goal of this study is to use ultra-high-resolution (UHR) PET imaging to better understand how the brain and spinal cord change in healthy aging and in neurological and psychiatric disorders such as Alzheimer's disease (AD), Parkinson's disease and related movement disorders, amyotrophic lateral sclerosis (ALS), and psychotic disorders. Researchers will use the NeuroExplorer PET/CT system, a new scanner that can show very small structures in the brain and spinal cord in much more detail than regular PET.
The main questions this study aims to answer are:
* How do small but important brain regions (like the locus coeruleus, substantia nigra, and thalamic nuclei) change in healthy aging?
* What early brain changes occur in neurodegenerative and psychotic disorders, and can they help improve early diagnosis?
Participants will:
* Undergo PET and MRI brain scans using different tracers that measure brain metabolism (18F-FDG), synaptic density (¹⁸F-SynVesT-1), dopamine transporters (¹⁸F-PE2I), and tau protein buildup (¹⁸F-MK6240).
* Complete cognitive and clinical assessments related to memory, mood, and motor or psychiatric symptoms, depending on their group.
This study will include healthy volunteers and patients with mild cognitive impairment due to Alzheimer´s disease, ALS, Parkinson's disease and related disorders, or psychotic disorders.
The results will help create detailed brain imaging maps for healthy aging and identify early biomarkers for different diseases to support better diagnosis and treatment in the future.