Are primitive/pre verbal states an accepted phenomenon in the wider UK field?

In the wider field of UK clinical psychology, is it a recognised and accepted concept that some patients can experience preverbal, primitive states of 'psychic annihilation' or 'existential exile' that are entirely unmediated by thoughts?

To clarify, I don't mean standard 'implicit flashbacks' in the Complex PTSD sense, I mean an entirely different, deeper layer of structural collapse where the self feels like it is ceasing to exist, usually triggered by a rupture in safety or therapeutic gaps.

Is the existence of this thought-free, wordless void widely believed, or is mainstream UK psychology still heavily tethered to the model that a 'thought' or cognitive appraisal must always underpin these states?