Brain
I am in Badrachalam, thinking loudly on something that we often say, "stress".
Let's say, if we have a 2GB pen drive, where we know, it stores / retrieves the data of 2 x 1024 x 1024 x 1024 bytes of data. What we know today about brain is very minimal. With that little understanding, today there are estimates to say, Human brain is capable of storing / retrieving ~2.5 peta bytes of data.
This bytes calculation of brain itself is a misleading, because brain stores / retrieves information (not as binary bits and bytes), as proteins, amino acids and their atomic interaction in neurons, which is almost infinite. I am saying infinite, because we don't know the number. Truly, there is no boundary for brain's capability, because as we train the brain, its capability seems to change. More we train, better it gets.
Now, many projects that we do on Artificial Intelligence (second brain ?!), essentially to ease the work of brain. Truly, we train the brain less, but improve training the the external computing devices. Therefore, higher the dependance on the so called second brain, would train (evolve) the brain towards its less capability. We have seen this practically in navigating in an unknown terrain with (today) and without (20 years back) the help of GPS devices.
My pointer here is something else. People often say, keep mind "stress free". Let me break this further. "Stress" in my understanding, is a thought process of certain complexity, which led to solution less and trigger certain emotion such as anger / fear / or similar. In my opinion, keeping mind stress free (= complexity free) will NOT help the brain to train better. If the brain needs to be trained towards its better capability, it has to be stressed. In other words, it has to be "used".
I know, this will contradict to the principles of meditation, however I feel, our brain has to experience stress (complexity). More we are into stress more we gain and more towards a "healthier brain".