As a scientist, this is a particular favorite of mine. Being able to utilize different body parts and activate/deactivate them with a single word is particularly useful, especially when it comes to more methodical experimentation.

This can be utilized one of two ways. One way to use this effect would be a simple on/off, like the flip of a switch. Letting the sensory regions fade off while the mental stays on allows for a delightful amount of confusion and chaos with given subject. The other alternative is a sliding scale, like a dimmer lightswitch. Utilizing it in this fashion would create a more gradual sense of change, which may be beneficial in long-term repeatability.

Examples of the above could be testing out different triggers in different environments to see which has the most effect, shutting off certain body parts under trance, etc. I've seen this used for memory manipulation, sensory deprivation chambers, emotional regulation, and many more things.