Introduction. Many physiological signals yield fractal characteristics, i.e. finer details at higher magnifications resemble details of the whole. Evidence has been accumulating that such fractal scaling is basically a consequence of interaction-dominant feedback mechanisms that cooperatively generate those signals. Neurodegenerative diseases provide a natural framework to evaluate this paradigm when this cooperative function declines. However, methodological issues need to be cautiously taken into account in order to be able to provide reliable as well as valid interpretations of such signal analyses. Methods. Two conceptually different fractal analyses, i.e. detrended fluctuation analysis (DFA) and analysis of cumulative distributions of durations (CDDs), are applied to actigraphy data of 36 geriatric in-patients diagnosed with dementia. The impact of the used time resolution for data acquisition on the assessed fractal outcome parameters is particularly investigated. Moreover, associations between these parameters and scores from the Mini-Mental-State-Examination and circadian activity parameters are explored. Results. Both analyses yield significant deviations from (mono-)fractal scaling over the entire considered time range. DFA provides robust measures for the observed break-down of fractal scaling. In contrast, analysis of CDDs results in measures which highly fluctuate with respect to the time resolution of the assessed data which affects also further derived quantities such as scaling exponents or associations with other (clinically relevant) assessed parameters. Discussion. To scrutinize actigraphic signal characteristics and especially their (deviations from) fractal scaling may be a useful tool for aiding diagnosis, characterization and monitoring of dementia. However, results may, besides contextual aspects, also substantially depend on specific methodological choices. In order to arrive at both reliable and valid interpretations, these complications need to be carefully elaborated in future research.

Studies have reported difficulties in decision making for patients with schizophrenia or depression. Here, we investigated whether there are differences between schizophrenia patients, depressed patients, and healthy individuals (HC) when decisions are to be made under risk and cognitive flexibility is required. We were also interested in the relationships between decision making, cognitive functioning, and disease severity. Thirty HC, 28 schizophrenia patients, and 28 depressed patients underwent structured clinical assessments and were assessed by the Positive and Negative Syndrome Scale or Hamilton Rating Scale. They performed the Probability-Associated Gambling (PAG) Task and a neuropsychological test battery. Both patient groups obtained lower scores than HC in memory and executive function measures. In the PAG task, relative to HC, depressed patients made slower decisions but showed a comparable number of advantageous decisions or strategy flexibility. Schizophrenia patients were slower, riskier, and less flexible compared to HC. For them, the decision making behavior correlated with the symptom severity. In both groups, decision making scores correlated with memory and executive function scores. Patients with schizophrenia or depression may have difficulties under risk when quick and flexible decisions are required. These difficulties may be more pronounced in patients who have marked cognitive deficits or severe clinical symptoms.

Mental illness is a common phenomenon at all ages. Various independent studies have shown that psychopathology is often expressed on a continuum from youth to adulthood. The aim of our study was to demonstrate a) the frequency of admission of former child and adolescent psychiatry inpatients (CAP-IP) to adult inpatient mental health facilities, and b) a potential longitudinal diagnostic shift. This is the first Austrian study designed to shed light on these issues. Nearly 1000 inpatient cases at a specialized child and adolescent care center were analyzed. These cases were then tracked using data matching with registry data from adult psychiatric institutions. Overall, our observational period was 23 years. 26 % of our sample of former CAP-IP used psychiatric inpatient mental health services as adults, thus indicating chronicity or reoccurrence. In line with previous literature, there were patients who stayed in the same diagnostic category as well as patients with a diagnostic shift from childhood to adulthood. Childhood and adolescence is a very important period for early intervention and prevention of mental illness. Our findings support the notion of the continuity of psychopathology from youth into adulthood.

Alzheimer’s disease (AD) is a neurodegenerative disease characterized by memory loss and progressive deterioration of cognitive functions. Being able to identify reliable biomarkers in easily available body fluids such as blood plasma is vital for the disease. To achieve this, we used a technique that applied human plasma to organotypic brain slice culture via microcontact printing. After a 2-week culture period, we performed immunolabeling for neurofilament and myelin oligodendrocyte glycoprotein (MOG) to visualize newly formed nerve fibers and oligodendrocytes. There was no significant change in the number of new nerve fibers in the AD plasma group compared to the healthy control group, while the length of the produced fibers significantly decreased. A significant increase in the number of MOG+ dots around these new fibers was detected in the patient group. According to our hypothesis, there are factors in the plasma of AD patients that affect the growth of new nerve fibers, which also affect the oligodendrocytes. Based on these findings, we selected the most promising plasma samples and conducted mass spectrometry using a differential approach and we identified three putative biomarkers: aldehyde-dehydrogenase 1A1, alpha-synuclein and protein S100-A4. Our method represents a novel and innovative approach for translating research findings from mouse models to human applications.

Alzheimer’s disease is a severe neurodegenerative disorder, and the discovery of biomarkers is crucial for early diagnosis. While the analysis of biomarkers in cerebrospinal fluid is well accepted, there are currently no blood biomarkers available. Our research focuses on identifying novel plasma biomarkers for Alzheimer’s disease. To achieve this, we employed a technique that involves coupling human plasma to mouse organotypic brain slices via microcontact prints. After culturing for two weeks, we assessed Iba1-immunopositive microglia on these microcontact prints. We hypothesized that plasma from Alzheimer’s patients contains factors that affect microglial migration. Our data indicated that plasma from Alzheimer’s patients significantly inhibited the migration of round Iba1-immunoreactive microglia (13 ± 3, n = 24, p = 0.01) compared to healthy controls (50 ± 16, n = 23). Based on these findings, we selected the most promising plasma samples and conducted mass spectrometry using a differential approach, and we identified four potential biomarkers: mannose-binding protein C, macrophage receptor MARCO, complement factor H-related protein-3, and C-reactive protein. Our method represents a novel and innovative approach to translate research findings from mouse models to human applications.

The ever-growing group of people living with dementia (PLWD) and their relatives face great challenges. The Covid 19 pandemic has once again placed a particular challenge on this vulnerable group. What started a decade earlier with telephone-based support groups experienced a real push during the pandemic in the form of video-based self-help services. The aim of this qualitative literature search in MEDLINE, EMBASE, CINAHL, and PsycINFO with keywords related to online, support group, caregiver, and dementia was to collect the reported experiences by the end of 2022. Peer reviewed journal papers were included when published and written in English. After the joint decision of two reviewers, it was decided to only include studies that were published in Medline. The results of the literature search are compared with experiences of the participants in a presentation group that was transformed into an online group at the time of the COVID-19 pandemic via Zoom. In search yielded a total of 129 articles. 113 articles described different types of interventions, 30 of which had a randomized design. The qualitative literature search showed on the one hand a high interest in online support groups but on the other hand that the effectiveness and efficacy in randomized trials is much less clear. In addition, we investigated the assessments and experiences of the participants in a presentation group that was transformed into an online group at the time of the COVID-19 pandemic via Zoom. This study demonstrates that PLWD and carers on virtual group meetings can express significant emotive capacity and enhanced connectivity with one another despite a diagnosis of mild to moderate dementia. Further research on entry criteria, concerns about online support services in general and necessary support for use is essential to develop the time- and location-independent possibility of video-based online self-help into an important form of support for both PLWD and their caregivers as an additional support option independent of exceptional pandemic situations.