Most people have probably heard of Maslow’s hierarchy of needs, one of the cornerstones of motivational theory. While rightly critized at times, the model does serve to demonstrate at least one thing: even small disruptions on the lowest levels (like physiological) serve to bring our target very efficiently, even if only temporarily, back down from the “higher” needs.
An example: if you get a splitting headache, you’re unlikely to appreciate any activities involved in fulfilling your self-actualization needs. Remarkably fast, your #1 concern becomes that of getting rid of the headache. And it doesn’t even need to be a headache – a splinter of wood in your finger or even a rock in your shoe suddenly makes the physical needs highly pertinent, regardless of what self-fulfilling higher level need you are fulfilling when the ailment strikes you. Moreover, it doesn’t need to be an abnormal event – hunger or thirst accomplish the same thing.
I wonder if anyone’s ever done an expirement where for a week people could not have any lunch or snacks during the working day. And then measure the effects of that on productivity. That should prove that Maslow’s hierarchy works at least with regards to the lowest level. If for some reason the effects aren’t clear, try denying bathroom breaks and the case will be closed 
Of course, then we also have people who never climb up from the lowest level or two.. How to get them to aim their goals a little higher?
