In TFTD, Psionics/Mind Control is renamed Molecular Control (or M. C. for short) - I presume this has something to do with the fact you control the molecular interactions in the brain of the victim, and they can do nothing, even if they want to - you can't do anything drastic with said molecules, but you CAN make the victim move about, fire weapons, etc.
The only technical differences is that aquanauts require implants to make use of Molecular Control. A loop hole in the M. C. theory is that the M.C. Disruptor works on land just as well as it does under water. Also, the implant in the attacker is used to influence the implant of the victim, while aliens simply attack the victim's brain.
While mainly an attempt to refresh an old idea, Molecular Control in all senses of the word is just another form of psionics.