Cognitive load theory names three distinct types of load, but researchers using self-report, physiological and performance-based measures have not converged on a way to isolate them from one another, and some findings suggest the three may not be additively separable in practice.
What would resolve this A validated measurement method, independently confirmed across labs, capable of isolating intrinsic, extraneous and germane load from one another in the same learning task.
OpenWikipedia: Cognitive Load