Proprioception is the body's ability to keep track of how it moves and reacts within an environment. Equilibrium is a type of proprioception, and the brain gathers information from vision and the other senses to determine if we are right side up or if we are falling over. You can demonstrate this ability by having students stand on one foot for one minute with their eyes open. Next have the students stand on one foot for one minute with their eyes closed. The brain isn't getting as much information from the visual field and has a little more trouble determining where the body is standing in its environment. Students will have to concentrate more to maintain the same stability as when they stood with their eyes open.
The brain also helps interpret nerve signals in other parts of the body to make minute adjustments or fast decisions. These fast decisions, called reflexes, can help keep the body out of harm's way. An example is the plantar reflex. Ask a student to take a shoe and sock off. Starting at the bottom of the foot, press a somewhat pointed object against the skin while moving up the foot. Stimulation of the sole should cause the foot to flex and the toes to move closer together. This would be the same response if that student were to step on a somewhat sharp object with his bare foot.
Short-term memory is when the brain stores a small amount of information for a short time period. In 1956 George Miller published a paper stating short-term memory can only hold seven plus or minus two pieces of information; this formula is still widely accepted today. To demonstrate this formula, call out a list of words. Once finished, ask the students to write down as many words as they can remember on a piece of paper. The average number of words written down should comply with the seven plus or minus two formula.
Humans have binocular vision, meaning while both eyes generally look in the same direction, they see slightly different views. The brain takes these different views and interprets them to allow us to see one conducive image. Instruct students to close their left eye while holding a pencil directly in front of their right eye. Have them position another pencil directly beneath the first and then move the first pencil back so when looking at the two pencils they seem to form a continuous line. Now have the students open their left eye and close their right eye; the pencils that were originally aligned are separated again.