Inclusion Criteria:  Over the age of 65 years Admitted to one of the included study rooms  Exclusion Criteria:  Overdose addictive substance Acute neurological disease Melatonin treatment Probable survival <5 days Severe visual impairment that makes reading impossible Age <65 years Inability to understand Swedish in speech and writing Inability to consent to participate in the study  The patient is on any of the following medicines:  Medications for Parkinson's disease Neuroleptics (including lithium) Dementia