This study paired a public-awareness survey with an in-silico microbiome comparison to explore the gut-brain axis in common neurological disorders. A structured, anonymous online survey captured responses from n = 230 participants drawn from a predominantly young, health-sciences-affiliated Indian cohort. Approximately three-quarters of respondents reported awareness of a potential link between gut health and mental health. Despite this awareness, roughly half the cohort indicated they did not follow any specific dietary practice aimed at influencing mental health via the gut.
Survey respondents also reported gastrointestinal correlates of stress: about 60% experienced stress-related digestive symptoms. The authors note that these symptoms were rarely followed by medical consultation, suggesting a gap between symptom experience and healthcare engagement in this cohort.
The comparative microbiome analysis used disorder-specific lists of faecal taxa reported as elevated or reduced in each condition, retrieved from the Disbiome database. These lists were compared using a multiple list comparator to identify overlapping and unique taxa across disorders. Taxonomic classification employed the NCBI Taxonomy tool, and phylogenetic trees were constructed and visualized in iTOL.
The combined approach—survey plus database-driven in-silico analysis—was intended to link public perceptions and symptomatic correlates with published microbial associations for four neurological disorders: depression, anxiety, schizophrenia and autism spectrum disorder (ASD).
Comparative analysis revealed a substantial overlap in dysbiosis patterns among depression, anxiety and schizophrenia. The disorders commonly showed elevation of specific taxa including Actinomyces, Bacteroidaceae, Blautia, Eggerthella, Oscillibacter, Parasutterella and Veillonella. Concurrently, these three disorders shared consistent reductions in taxa such as Coprococcus, Lachnospiraceae, Ruminococcaceae, Clostridium, Faecalibacterium and Sutterella.
This shared signature suggests a set of microbial changes that co-occur across multiple psychiatric diagnoses, supporting the idea of a common microbial pathway that may link these conditions via the gut-brain axis.
In contrast to the overlap observed among depression, anxiety and schizophrenia, ASD presented a microbiome signature that was largely distinct, with only limited overlap with the other three disorders. The authors highlight that ASD’s dysbiosis pattern does not align closely with the shared set of elevated and reduced taxa identified for the psychiatric disorders evaluated.
This distinction indicates that while broad phylogenetic shifts can be common across neurological disorders, disorder-specific microbial signals—particularly in developmental conditions such as ASD—may be different and warrant tailored investigation.
Phylogenetic clustering of the aggregated taxa showed that the shared dysbiotic taxa between depression, anxiety and schizophrenia were predominantly affiliated with four phyla: Bacillota (formerly Firmicutes), Bacteroidota (formerly Bacteroidetes), Actinomycetota (formerly Actinobacteria) and Pseudomonadota (formerly Proteobacteria).
The authors note that this phylum-level pattern mirrors observations from comparative analyses of microbial dysbiosis in neurodegenerative diseases. This parallel suggests that large-scale shifts at the phylum level may be a relatively general correlate of chronic neurological disease, whereas specificity for particular disorders appears at the level of individual genera or families.
The study’s findings support the existence of a shared microbial pathway linking depression, anxiety and schizophrenia, distinct from the dysbiosis profile observed in ASD. From a translational perspective, this supports the rationale for microbiome-informed, disorder-specific therapeutic strategies, including targeted dietary interventions, probiotics/prebiotics, or other microbiome-modulating approaches tailored to the microbial signatures associated with particular disorders.
The survey results—high awareness but limited dietary practices and infrequent medical consultation for stress-related digestive symptoms—highlight potential opportunities for patient education and earlier clinical engagement around gut-related symptoms in populations at risk for or living with neuropsychiatric disorders.
The authors relied on public database-derived lists (Disbiome) and in-silico taxonomic and phylogenetic tools (NCBI Taxonomy, iTOL) for the comparative analysis; detailed methods beyond those summarized here and the raw data lists were not provided in the summary. The survey sample was described as predominantly young and health-sciences-affiliated, which may limit generalizability to broader populations. Specific numerical details of the taxa lists beyond the named genera and families were not reported in the abstract.
The authors declared no competing interests. The preprint reports that the copyright holder granted bioRxiv a license to display the preprint in perpetuity.