Chronic hypervigilance (learned dread)

Many ADHD adults live in a constant low-level state of unease described as a „tiger behind every tree.” It is often described as a trauma-style adaptation: after years of forgetting, lateness and consequences, the brain „learned” that relaxing leads to something going wrong, so it keeps a sympathetic guard up around the clock. This is a plausible explanatory model (borrowing from trauma research), not a proven ADHD-specific mechanism. ADHD and trauma/PTSD often co-occur and post-trauma hypervigilance can mimic ADHD, but „learned chronic sympathetic readiness” remains a hypothesis. This differs from momentary arousal or racing thoughts: it is a chronic baseline, not a single evening episode.

The sleep impact is direct: you can’t sleep if you can’t relax, and you can’t relax if the nervous system doesn’t feel safe. Sympathetic activation (fight-flight-freeze) reroutes blood and oxygen away from the prefrontal cortex, so trying to „calm down by willpower” fails. People with ADHD also feel emotions faster and more intensely with weaker self-soothing, making it harder to down-regulate worry before bed.

Unease fades not when problems stop but when the brain decides it can handle things going wrong. Building a sense of safety and capability (rather than eliminating every threat) is what lets the nervous system stand down and allow sleep.