"The best time to assault your enemy's mind is when his flesh is being torn asunder." - Relluri, psion adept.
Powerful psionicists have developed a technique to imbue their weapons with latent psionic energy. This allows the weapons to attack a victim's mind in addition to their body.
This is a delicate art. Weapons need a certain degree of freedom to be able to launch psionic attacks. Hence, these mental attacks only occur when the weapons are controlled with telekinesis.
In general, a psionicist can only imbue a single type of psionic attack into their weapons at a time. Some more advanced techniques are less likely to conflict.