Explain why the spatial impossibility of an extracampine hallucination is worth noting specifically, given that it does not change the underlying perceptual quality of the experience.

Although the extracampine location does not change the underlying hallucinatory process itself, noting it specifically is useful because it highlights just how completely disconnected the hallucinated perception can be from any genuine physical constraint, underscoring that the experience is generated entirely internally with no relationship whatsoever to what could actually be sensed from that position. Documenting this detail precisely also helps distinguish it clearly from perceptual experiences that, however unusual, remain at least physically plausible, and it can be a useful, specific descriptive detail when characterising the full range and severity of a patient's hallucinatory experiences over the course of an assessment.