Well, you'll want to start by zeroing in on exactly what you mean by "cognitive performance." The abstract of the study the linked article is about has this to say:

>Pre- and post-training, participants completed cognitive assessments and functional magnetic resonance imaging (fMRI) during performance of validated decision-making tasks: delay discounting (choices between smaller rewards now vs. larger rewards in the future) and risk sensitivity (choices between larger riskier rewards vs. smaller certain rewards).

You could certainly imagine doing things to get better at these kinds of tasks---including practicing these tasks. Whether this gets at some kind of murky "cognitive performance" thing depends on how much you're into phrenology and dualism.

Since it seems like you want a scientific answer to this question, you'll always have to confront the realities of experimental design, and because of that, you'll have to nail down exactly what it is you're after. And "cognitive performance" isn't nearly specific enough.