When practicing insight meditation and when observing mental formations arising then sometimes shortly after another mental formation arises caused by the first mental formation.
An example could be a memory that arises then shortly after another memory arises that is closely related to the first one. The second memory is clearly caused by the first one since its similar in appearance and "acts" like a continuation of the first memory.
This picture is from Comprehensive Manual of Abhidhamma by Ven. Bhikkhu Bodhi. The picture can be found in the chapter "Compendium of the cognitive process", at p. 155. It shows the different stages in the process of cognition.
I was wondering about at what stage in the cognitive process it happens that an object is compared/coupled to previous experiences?
My best guess is that it might be in the stage of "investigating consciousness".