If you want your memory or executive function to improve, stare out a window at the skyline or sidewalk or trees or birds on the electrical wires for like 20+ minutes per day. (With no other stimulation like a podcast or TV if you can manage but hey baby steps innit). If you're fortunate enough to have safe outside with any bits of nature, go stare closely at a 1 meter square of grass and trip out on the bugs and shapes of grasses and stuff.

Literally this will make you smarter. Our brains HAVE TO HAVE this zone out time to do important stuff behind the scenes. This does not happen during sleep, it's something else.

That weird pressurized feeling you get sometimes might be your brain on no defrag.