The Science
Umwelten is evidence-transparent: every claim traces to its source, and the wiki is honest about what evidence supports and what it doesn’t. This section collects the research foundations: synthesised overviews, individual paper summaries, and explicitly documented gaps.
Core topic overviews
Sensory processing in autism and intellectual disability — the central synthesis. What we know about how sensory processing differs when autism and ID co-occur, why it matters, and what the evidence says.
Predictive processing and autism — the theoretical framework explaining why autistic brains process sensory information differently: altered precision weighting of predictions versus sensory evidence.
Masking and camouflaging — the evidence on what happens when autistic people suppress their natural responses to appear neurotypical. Documented mental health consequences.
Genetic heterogeneity in autism — autism is not one thing genetically. Four distinct clusters, different developmental pathways, different implications.
Evolutionary origins of neurodivergence — grounding autism and ADHD in deep evolutionary history through Neanderthal DNA and ancient genetics.
Models of disability — medical, social, neurodiversity, and capabilities approaches. The philosophical frameworks that shape how we understand (and respond to) neurological difference.
The diagnosis question — what autism diagnosis is, what it does, and the philosophical questions it raises.
Diagnosis and healthcare
Diagnostic pathways — how autism and ADHD diagnosis actually works in the UK and across Europe. Waiting times, system design failures, the NAIT pathfinder work in Scotland, and the neuro-affirming practice shift.
Autistic healthcare experience — what happens when autistic people encounter healthcare systems designed for a different neurology. Professional ignorance, sensory barriers, processing demands, and the gap between recommended adaptations and reality.
Conditions and co-occurrence
ADHD — as a neurodevelopmental difference. Core features, co-occurrence with autism, the mismatch theory.
AuDHD — when autism and ADHD co-occur. Internal contradictions, compounded masking load, and a profile that is more than the sum of its parts.
The overlap problem — autism, ADHD, dyspraxia, dyslexia, and Tourette’s are classified separately but co-occur so often the separation looks more like a filing system than biology. Genetic evidence for shared architecture.
Executive function — the cognitive architecture connecting sensory processing to daily functioning. Distinct profiles in autism (rigidity) versus ADHD (impulsivity), and the bidirectional interaction with sensory load.
Autistic burnout — prolonged exhaustion, skill loss, and reduced sensory tolerance from sustained masking and environmental mismatch. Distinct from depression, requiring different intervention.
Late diagnosis — who gets missed, why, and what decades of unrecognised neurodivergence cost. The intersection of gender, race, diagnostic overshadowing, and masking.
Alexithymia and autism — difficulty identifying emotions, 50% co-occurrence with autism, the connection to interoception.
Serotonin system and autism — genetics, blood markers, the 5HT₂A receptor, and the PSILAUT psilocybin trial.
Evidence gaps
The wiki documents what is not known as explicitly as what is known:
- Adult sensory processing gap
- Dutch validation evidence gap
- Interoception in intellectual disability gap
- Sensory processing intervention predictor gap
- The evidence problem in sensory interventions — why the evidence base for sensory interventions is weaker than people think, and why
Paper summaries
The wiki includes summaries of individual research papers. Browse them all via the type/research tag, or start with the most frequently cited across the wiki:
- Werkman 2020 — the counter-intuitive finding on cognitive abilities and sensory processing
- Werkman 2022 systematic review — the PRISMA review of sensory processing in autism with ID
- van Berckelaer-Onnes et al. 2018 — the SGL literature synthesis
- Litman, Sauerwald et al. 2025 — genetic heterogeneity and four autism clusters