Do you experience “Now” at the same time as I do? It follows, as a direct consequence of having bodies that perceive and interact with the world using chemical nerve signals, that we don’t experience the world directly. Whenever we see, touch, hear or otherwise sense our environment we are experiencing the world as it was a split second ago, the time required for signals to move around the body and then get processed in the brain to generate our sensation of living in the world is small but real. This also means that our brain has to work to synchronize all of the disparate signals into a coherent whole, this means there is a delay built into the system to allow for all of the signals to arrive before allowing the perception to filter into our conscious awareness.

One of the additional consequences of this process is that your perception of “now” may depend on how tall you are. After a little thought this becomes obvious as the signals from the end of a tall person’s leg will arrive at their brain after a longer period that that of a shorter person. This delay is actually further exacerbated by the fact that as nerve cells get longer they also tend to get thinner, and thinner nerves carry signals slower than thicker ones. Studies have shown that a signal will travel 0.27m/s (metres/second) slower for every extra centimetre.

Putting this all together means that the in-built delay that allows us to experience a synchronized picture of our surroundings must be longer for tall people than for everyone else. Or in other words, their “now” is later than my “now”, and mine might be later than yours. So if your larger companion seems a little slow on the uptake, don’t be too hard on them, it’s just the way they are wired.