If you're wanting to really get your whole brain optimal, everything everyone else said, but most of all something like animal/human tracking is your ticket.
When you hear from people who have gone to study at wilderness awareness schools or who have taught themselves though books or have been lucky enough to have their own mentor, the thing they comment most on I've noticed, is how this school of study/way of being/living meditation rewires their brains in a way that connected everything together and teaches them how to think, instead of the way most of us are taught in school which is what to think. And really it does more than just join all parts of of your brain together, it makes you a complete unit, your senses and your cognitive functions become one highly unified system instead that is really a level beyond what most people will experience in our modern world. This has several causes.
One is that tracking is built in to your genes, your ancestors have been expert trackers for thousands if not millions of years. That gets coded in to you over time. When you begin to track (in a native, close to the earth way, NOT western left-brained-only tracking, I cannot emphasize this enough!!!), you awaken something very old inside of you, something very deep and profound. Just as you would expect given the way DNA works as a light/data storage and communication system.
Two is that when you are out practicing these age old awareness techniques you stop thinking and you start feeling, as Jon Young says, "Lose your mind, and come to your senses" This literally means to quit the constant chatter that goes on in your mind, the ever present monologue you have going that thinks it's ~50,000 +- thoughts per day, and be in your body, in the present. This is what traditional meditation practices aim to do, but the reason this is such a good way to accomplish this, is because it gives you a hook to hang this on, you have a purpose in the forest, whether it is to hunt and find food, or avoid large predators like bear or wolves, or know when other people are around.
And three and most importantly for the purposes of this thread, when you are tracking, you are using all your resources together in a way western schooling teaches you not to. Think about when you go to class, typically, a normal day might look like this... 1st period, math, 2nd period, chemistry, 3rd period history, then lunch/break time, 4th period Gym, 5th period, Economics or what have you. The point is, everything is compartmentalized, and guess what, you compartmentalize in the way you store and retrieve it. That is why math is so fucking abstract, same with science and literature and..... But everything is connected in the real world, you could express the whole world in numbers, or the whole world in art, or the whole world in words, or in scientific classification, or a mosaic of all of the above. Imagine if you were taught about life in some sort of deeply connected way. Well this is what tracking does, it forces you to use every last resource you have to the fullest extent without putting borders between things.
If I want to know when a wolf passed by, I need to know things like how the weather was, windy, rainy, sunny, cloudy? I need to pay attention to it's personal "finger-print", the pattern of cracks and details the wolf's paw makes so I can identify this wolf if I run across these tracks in another place in order to form a profile of this wolf's behaviour. I need to know the layout of the terrain, or if you are in new terrain, you need to be able to make educated guesses of the layout so you can figure out what the wolf is up to, is she headed to water? Stalking prey? Wounded (dangerous)? Trotting in a baseline gate? And when you get really good at tracking you'll be able to recognize in each track which way the animal was looking, whether it's stomach was full or empty and a hundred other things about it. This practice of using your brain in a fluid and highly diverse way, combining logical/linear left brain thought with sensory and creative right brain perception in a unified whole to accurately and quickly uptake and process the world around you.
Most people won't truly grasp the impact and profundity of the above words, but tracking and awareness (wide angle (owl) vision, foxwalking, bird/alarm language) was one of the greatest changes I have ever experienced, it changed my life in a way similar to RVAF eating, it was like I was blind before, and only afterward really seeing color.
Recommended Reading:
Anything by Tom Brown Jr.
Jon Young
Tamarack Song
Ingwe