Symptoms of SMD
Synthetic memory degradation (SMD) was a rare medical condition that affected cyborgs with new implants, caused by miscommunication between the implant and the hippocampus. Initial symptoms were cognitive changes, hormonal overdrive, and olfactory differences; eventually the brain would liquefy and leak out the nose. Potential treatments included administering unexpected pain, as the reaction could often "kick" the neurons back into place, and medical venom.
In 2381, when Ensign Sam Rutherford changed his opinion about several matters after receiving a new implant, Ensign D'Vana Tendi became insistent that he was experiencing SMD. She went to extreme lengths to attempt to treat him, but ultimately admitted that she knew he did not have SMD. Rather, she was worried that his opinion changes would include no longer wanting to be her friend. (LD: "Strange Energies")