The mechanisms underneath, with the limits left in. Including where the popular version has outrun the evidence.
There is a particular way that psychology research reaches the public. A finding is published with careful hedges and a modest effect size. It gets summarised. The summary gets summarised. Four steps later it is a confident sentence on a gradient background, the hedges are gone, and someone is selling a device based on it.
These pieces go the other way. Each one takes a mechanism that actually explains something about how people feel, and reports what the studies found alongside what they did not. Sometimes that makes the concept more useful, because knowing that grounding interrupts attention rather than treating anxiety tells you exactly when to reach for it. Sometimes it makes it less impressive, which is the point: polyvagal theory has given a generation of clinicians a genuinely useful vocabulary and its evolutionary premises are disputed by comparative physiologists, and you deserve to know both.
The through-line, if there is one: almost every concept here is better understood as a description of a process than as a thing you can fix. That is less satisfying than the version being sold to you, and it is considerably more use when you are trying to work out what is happening at two in the morning.
4 pieces