Question: Will it ever be possible to plant a microchip in someone's brain to control what they think and feel? For example in Star Wars, the clone army had a microchip planted in their brain so they would obey "Order 66" .

Joe Bathelt answered on 16 Nov 2016:

Hmm, this is a tricky question. On one hand, there are already implants stimulate certain parts of the brain. For example, in some cases of Parkison’s disease, electrodes are implanted to help patients to control their movements better – Parkinson’s leads to unwanted tremor of the hands and difficulties with initiating and stopping movement. There are also some emotional symptoms of this disorder that seem to improve with deep brain stimulation. However, this is not like putting thought directly into someone’s head.
The difficulty is that thoughts are happening in the brain, but they represent the activity as a whole. So, we cannot just add a bit of activity somewhere to create a very specific thought. Maybe we will have a better understanding of how the brain works in the future and will be able to do this. There might also be a difficult engineering problem, because we will probably have to be able to reach any part of the brain but stimulate only very specific parts.