I've been suffering from Vertigo. When dizzy (which is pretty much most of the time) I feel dizzy, but no less intelligent than normal. This, however, is an illusion. When my ear/eyes/brain malfunctions, all the normal balance functions taken care of by the hindbrain move right up to the cerebrum, displacing things like, uh, speaking, rationality, etc. Disturbing, esp., as I can't feel it. I never feel dumber, just more miserable.
I just read an interesting article(please read) describing how people who feel less in control of their lives find more spurious patterns than those with more control. Looking at my own pattern, I feel free to suppose that those with less brainpower find more nonexistent patterns than the smarter among us. Yes, I think we're hardwired to find patterns, even when none exist. It is actual difficult work for us to determine which patterns are real and which are figments of our inborn overactive imaginations.
Why, you say? Uh, well, one totally non-scientific data anecdote. I've noticed that when I feel especially vertiginous, I assume the actions of my beloved fiancee (take a bow, Geebee), my family, and assorted souls with walk-on parts, have rather more significance (mostly negative) than warranted. That is, I see nonexistent patterns in their behavior. More specifically, I am much more difficult, more touchy, seeing slights where none were intended. Matching nonexistent patterns willy-nilly, and, as it seems to me, oh-so-cleverly. When my vertigo clears, the patterns, the significance, the pattern disappears. The actions are just people doing stuff. No global significance attached. That is all.