On Thursday, 8 October 2026, Dr Andreas Müller spoke at the Logosynthese Institut Schweiz in Bad Ragaz and online about ADHD within the spectrum of neurodiversity. The key points are summarised here; the slides are available for download (in German).
Two adults, one diagnosis
Marco, 38, is permanently wired: restless inside, starts a great deal and finishes little, irritable, sleeps badly. Nina, 42, drifts off as soon as things go quiet: loses the thread in meetings, forgets and postpones, was always considered disorganised — her diagnosis came only when her child was assessed. Both examples are fictional and typical of adult practice. Both meet the criteria for ADHD.
Same diagnosis, same recommendation? The diagnosis describes behaviour. It does not say what is going on in the brain. And it counts: 18 criteria in two lists, five of nine for adults, onset before the age of twelve — established retrospectively. Nowhere does it say why.
ADHD in the spectrum: cuts through a continuum
Between ADHD, autism, high sensitivity, anxiety and the consequences of trauma, the transitions are fluid. Three points. Comorbidity is the rule — among adults with ADHD, anxiety and depression occur in roughly half, and autistic traits, addiction and trauma sequelae are common; pure cases are rare. The dimensions run across the diagnoses: openness to stimuli, level of arousal, stress regulation. And: not defective, but wired differently — with strengths and with costs.
Two anchors: what a person experiences, what the organism measurably does
One side is the subjective: history, development, questionnaires, behavioural observation, the experience of the person and those around them. Its limit is masking, compensation, expectation. The other side is the measurable: spectra, event-related potentials and microstates in the EEG, arousal, vigilance and sensitivity as state measures, heart rate variability and sleep, and placement against a normative database. Its limit: a finding alone is not a diagnosis.
Together they make for evidence-based assessment — two anchors that check one another. Where they agree, the diagnosis is robust. Where they contradict each other, the real work begins.
Three measurement perspectives
Frequency spectra show how aroused a brain is. The best-known ADHD finding — too much theta, too little beta — applies only to a subset, and in adults less often than in children. Under the same diagnosis there are at least four patterns: hypoaroused, slowed, excess beta, and an unremarkable spectrum.
Event-related potentials show the brain at work: how strongly is a stimulus taken in (P1, N1)? Does the system prepare for the next one (CNV)? And how much resource is available for deciding and braking (N2, P3)? In ADHD the P3 is typically smaller and later.
Microstates show where the brain spends its time. The resting EEG holds a pattern for 60 to 120 milliseconds and then flips; four classes account for most of it. Duration, frequency and transitions tell whether a state sticks or whether the system jumps too fast.
Three state measures — and a paradox resolved
Arousal asks: how awake is the brain? Vigilance asks: does it stay awake — across 21 minutes of the same dull task? Sensitivity asks: how much comes in at all?
The answers diverge. In a sample of 958 adults (Müller, Candrian & Pershin, submitted), more ADHD symptoms go with a less aroused brain (β = −.14), while more anxiety goes with more arousal (β = +.12). That makes the old paradox intelligible: an under-aroused brain seeks stimulation — movement, noise, conflict, screens. Marco’s «wired» state is self-stimulation. This is why stimulants have a calming effect: they raise arousal, and the self-stimulation becomes unnecessary. Conversely, someone who really is over-aroused becomes more restless on them.
Vigilance is not the same as arousal: one can start awake and drift off after eight minutes. That is precisely what explains Nina’s inattention — and, in some people, hyperactivity as an attempt to stay awake.
Sensitivity separates out a group that regularly arrives in practice as a «suspected ADHD» case: highly sensitive people report distractibility, overload and exhaustion (β = .26 for the association with ADHD symptoms), yet under task they show markedly higher arousal (d = 0.54) with unremarkable vigilance (r = .01). This is a different population from hypoaroused ADHD — and it needs stimulus dosing and recovery rather than activation.
What it costs the system
Sensitivity is the input, arousal and vigilance are the state, stress is the cost. In ADHD the stress axis is often flat: low cortisol, a flat heart rate response — pressure and deadlines are felt too late, and then everything arrives at once. Added to this are the secondary costs of decades of failure, criticism and job changes: anxiety, depression, exhaustion, loss of self-worth. In adulthood these are often the real burden — and what clients bring to counselling and coaching.
Four profiles, four treatment logics
| Profile | Everyday life | Medication | Therapy |
|---|---|---|---|
| A hypoaroused → activate | structure, movement, sleep; external pacemakers | stimulants first choice — they raise arousal | neurofeedback on arousal, coaching for routines |
| B over-aroused → dose the stimuli | less stimulation, predictability, windows for recovery | stimulants not first choice; treat anxiety and sleep where needed | psychotherapy, HRV biofeedback, relaxation |
| C vigilance-unstable → give rhythm | sleep, light, breaks every 10 to 15 minutes | a low dose is often enough; timing across the day | neurofeedback on vigilance, self-monitoring, tracking |
| D wired → calm down | defuse workload and conflict, sleep hygiene | stimulants with caution | stress regulation, psychotherapy, neurofeedback for calming |
The profiles are prototypes; in practice mixed forms occur. The sentence behind them is what matters: the profile, not the diagnosis, determines the treatment. And the same technique can help one client and harm another — whoever does not wake up needs activation; whoever does not come down needs dosing.
Course rather than snapshot
The brain function analysis is followed by the treatment plan and then by the check: brief weekly ratings in everyday life — from those affected, from partners, where useful from the work environment — on sleep, stress, concentration and mood. They show early whether a measure is working. After about twelve months the brain function analysis is repeated: has the operating state changed — arousal, vigilance, P3, stress system — or only the behaviour? From that follows: continue, adjust, or taper off.
Limits
The profiles are prototypes, not categories. Group findings are not the individual case. Medication belongs in medical hands. And brain function analysis complements clinical assessment — it does not replace it.
Three sentences to take away
- Same diagnosis, different brains: ADHD is a spectrum of operating states, not one brain.
- Arousal, vigilance and sensitivity separate what behaviour mixes together — and they decide between activating and dosing.
- Understand first, then treat: the plan comes out of the profile, and the course shows whether it is right.
The theme continues at the Biomarker Workshop on 10 December 2026 at the Paulus Akademie in Zurich: «Sensitivity and stress in ADHD, autism and PTSD».
Literature and the background paper «Sensitivity and stress in ADHD, ASD and PTSD» on request: andreas_mueller@hin.ch