“Our experience of reality,” says neuroscientist David Eagleman, “is constrained by our biology.” As humans, we only ‘see’ electromagnetic waves in the range from around 430 to 790 THz,, we only hear audio waves between roughly 20Hz and 20kHz, and so on. Eagleman uses the German word umwelt (meaning ‘environment’, or ‘surroundings’) to describe that tiny slice of reality that we are aware of, but which we often take for the entirety of existence:
Each organism presumably assumes its umwelt to be the entirety of objective reality. Until a child learns that honeybees enjoy ultraviolet signals and rattlesnakes see infrared, it is not obvious that plenty of information is riding on channels to which we have no natural access. In fact, the part of the electromagnetic spectrum visible to us is less than a ten-trillionth of it. Our sensorium is enough to get by in our ecosystem, but no better.
However, in the TED Talk below, Eagleman points out that the beauty of brains is that they are effectively a ‘universal translator’ of signals from the outside world, and will adapt (over time) to new types of input. “Your brain doesn’t know, and it doesn’t care, where it gets the data from”, he notes. “Whatever information comes in, it just figures out what to do with it.”
This “frees up Mother Nature”, Eagleman suggests, “to tinker out with different types of input channels”. So our eyes, ears and fingertips, the heat pits on a snake, the electroreceptors of the ghost knife fish, and the magnetites birds use to navigate, are basically “peripheral plug and play devices”.
The lesson that surfaces is that there’s nothing really special or fundamental about the biology that we come to the table with, it’s just what we have inherited from a complex road road of evolution. But it’s not what we have to stick with.
From these principles, Eagleman points out that we are in a position to create interfaces that enable both sensory substitution (for those who may be deprived of a sense, of say sight or hearing), and also sensory augmentation: allowing us to expand our umwelt to include more of both the natural world (e.g ‘seeing’ the infrared part of the spectrum), and even perhaps to include other aspects of human thought or action, such as by using sentiment analysis on social media or data from the stock market to allow us to sense changes to these things in real time.