It appears that Evolution is taken a wrong path when choose to centralize the sensor to become Central Nervous System.
The exact wording should be there are certain price paid in exchange of the advantage of centralize the sensor, and the later appear to be formation of higher cognitive ability(Learning from experience, Generalize from input of various sensor, Abstract thinking). For instance, in case of some animal to avoid a smell that is too strong and bad to bear, as well as avoiding bright light, loud noise… etc. The above avoidance may not confer any evolutionary advantage to the animal. I suspect many of them are simply the unintended/accidental consequence of centralization of sensor. It is not necessary that evolution taken this path, we can imagine a world full of decentralized-sensor organism.
So if we are going to redesign organism, we must find a way to prevent the centralizations of sensor produce any side effect to an organism’s behavior. i.e. The organism would still learn from experience, do some form of higher analysis; while without the behavior of avoiding ‘bad stimulation'(odor unpleasing to nose, light unpleasing to eye and noise unpleasing to ear… etc) unless that is necessary for survival of this organism. If anyone is able to manufacture such an organism, that organism would quickly dominate any environment.