Significance and cognition are closely related but not identical.
Significance concerns what matters to a living system. Through biological evaluation, organisms distinguish conditions according to their consequences for viability, functioning, adaptive persistence, and future possibilities.
Cognition concerns the adaptive use of what matters. Learning, memory, anticipation, behavioural flexibility, and context-sensitive regulation all require significant conditions to be related to one another and organised into coherent patterns.
A condition may therefore be significant without yet being cognitive. Significance identifies relevant differences, but cognition requires those differences to be integrated into broader patterns of organisation.
Integration provides the bridge between these concepts.
In APS:
Significance identifies what matters.
Integration organises what matters.
Cognition uses what matters.