I don't think mere "cognition" is necessarily helpful.
And Buddhism might regard "cognition" as merely another sense, the 6th sense -- i.e. with the "cognition of thoughts" being objects of the mind, comparable with the "seeing of sights" being objects of the eye.
Examples of mere cognition might, I suppose, include watching videos, reading books, arguing online, doing cross-word puzzles...
What might be more helpful is "directed" thought, purposeful, intentional -- and preferably with a motive which aligns with Buddhist values and morality (e.g. beneficial, harmless, liberating).
I think that's related to "energy" -- i.e. that's a type of cognition which is associated with, from which derives, a self-sustaining energy.
I don't know of a canonical reference to justify this answer, though.
This article -- The Seven Factors of Enlightenment -- implies there may be some connection between "energy" and "purposefulness":
The third enlightenment factor is viriya, energy. It is a mental property (cetasika) and the sixth limb of the Noble Eightfold Path, there called samma-vayama, right effort.
The life of the Buddha clearly reveals that he was never subjected to moral or spiritual fatigue. From the hour of his enlightenment to the end of his life, he strove tirelessly to elevate mankind, regardless of the bodily fatigue involved, and oblivious to the many obstacles and handicaps that hampered his way. He never relaxed in his exertion for the common weal. Though physically he was not always fit, mentally he was ever vigilant and energetic. Of him it is said:
Ah, wonderful is the Conqueror,
Who e'er untiring strives
For the blessing of all beings, for
the comfort of all lives.
Buddhism is for the sincerely zealous, strong and firm in purpose, and not for the indolent (araddhviriyassayam dhammo nayam dhammo kusitassa). The Buddha {etc.}
And "mindfulness" ought to be helpful -- that is assuming that "mindfulness" means not just "attention" but "remembering the Dhamma".