Autophagy-Enhancers to Reduce Sleep Disturbances

Inclusion Criteria (SCD participants): * Men and women * Written consent to participate in the study * German at native speaker level * Age between 55 and 75 years * Subjective Cognitive Decline operationalized as: 1. Subjectively reported decline in cognitive function (particularly memory) despite objectively normal cognitive performance (e.g., WMS-LM) 2. Preservation of functional independence 3. No dementia Inclusion Criteria (MCI patients): * Men and women * Written consent to participate in the study * German at native speaker level * Age between 55 and 75 years * Mild cognitive impairment (MCI) operationalized as: 1. A change in cognitive abilities reported by the patient, relatives or clinic staff (i.e. historical or observed evidence of deterioration over time) 2. Objective evidence of memory impairment (at least 1.0 Standard Deviation (SD) below the normal range on the Wechsler Logical Memory Scale (WMS-LM)); other cognitive domains may also be affected (i.e. amnestic MCI and amnestic + MCI) 3. Preservation of independence of functional abilities 4. No dementia Exclusion Criteria (SCD and MCI participants): * Patients who are unable to give informed consent * Polyamine intake via dietary supplements and/or participation in corresponding intervention studies * Dementia according to the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) * Any condition that impairs clinical or neuropsychological examination procedures * Diabetes mellitus * Polycystic ovary syndrome * Signs of epilepsy, focal brain lesion or head injury with loss of consciousness or immediate post-injury confusion * Previous stroke * Severe untreated medical problems or unstable medical condition * Current major depressive episode * Psychotic disorder * Bipolar disorder * Current or previous substance abuse * Other neurodegenerative disease, e.g. Parkinson's disease * Vascular dementia * Alcohol abuse * Participation in an interventional study in the last 3 months and during the entire study period * Sleep disorders * Taking medication that primarily affects the central nervous system (e.g. antipsychotics, antidepressants, benzodiazepines or any type of over-the-counter sleep-inducing medication such as valerian; anti-dementia medication) * Known intolerances or allergies to wheat germ, gluten or histamine Inclusion criteria (healthy controls): * Men and women * Written consent to participate in the study * German at native speaker level * Age between 55 and 75 years * Subjective cognitive disorders are denied Exclusion criteria (healthy controls): * Subjects who are not able to give informed consent * Polyamine intake via dietary supplements and/or participation in corresponding intervention studies * Dementia according to the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) * Mild cognitive impairment (MCI), defined as described above in the patient inclusion criteria * Any condition that interferes with clinical or neuropsychological examination procedures * Diabetes mellitus * Polycystic ovary syndrome * Signs of epilepsy, focal brain lesion or head injury with loss of consciousness or immediate post-injury confusion * Previous stroke * Severe untreated medical problems or unstable medical condition * Current major depressive episode * Psychotic disorder * Bipolar disorder * Current or past substance abuse * Other neurodegenerative disease, e.g. Parkinson's disease * Vascular dementia * Alcohol abuse * Participation in an interventional study in the last 3 months and during the entire study period * Sleep disorders * Taking medication that primarily affects the central nervous system (e.g. antipsychotics, antidepressants, benzodiazepines or any type of over-the-counter sleep-inducing medication such as valerian; anti-dementia medication)