Multiple personality disorder Multiple personality disorder , or simply multiple personalities , is a psychological condition in which an individual exhibits two or more distinct personalities , often with separate memories and periods of control over the body . In 2266 , a transporter malfunction divided Captain James T . Kirk into two separate physical individuals , each with a certain set of character traits : one gentle but indecisive , the other assertive but brutal . The compassionate Kirk had to realize that the " wolf " was necessary to his functioning as a starship captain . The two aspects , when " integrated " back into a single body , helped to balance and temper one another . ( ) The Kurlan people believed that each individual was a community of persons , each with its own voice , desires and outlook . A Kurlan naiskos was a ceramic statue of a person which opened to reveal many smaller figures inside . ( ) When the " Enterprise " encountered a huge archive from the D ' Arsay system , Data was affected by the archive ' s sensor beams and began to display several archetypal personalities from D ' Arsay mythology . He said later that there were actually thousands of people in his mind . ( ) Jadzia Dax struggled with what appeared to be the repressed memories of Joran Dax , one of the previous ( unauthorized ) hosts of her Trill symbiont . She experienced his memories when triggered by a particular piece of music and manifested certain aspects of his personality traits . ( ) Later , Jadzia participated in a ceremony in which the spirits of former hosts of her Trill symbiont were temporarily channeled by her fellow Deep Space 9 crew members . Curzon Dax and Odo liked their co - existence so much they considered staying that way . ( ) In 2372 , aspects of both Tuvok ' s and Neelix ' s personalities were combined together when , after another transporter error , their bodies were merged into a single individual called " Tuvix " . Tuvix felt he was a unique individual and wanted to stay as he was . Thus , it was only with the intervention of Kathryn Janeway that Tuvix was separated again . ( ) In 2375 , Seven of Nine experienced something akin to multiple personality disorder when a malfunctioning Borg vinculum tapped into her cortical implant and caused the neural pattern s of assimilated individuals to emerge . The symptoms worsened until she began to show a different personality every few seconds , causing severe stress on her cerebral cortex and threatening her life . The crew of the was able to save her life by deactivating the vinculum . ( ) Apocrypha . In Diane Duane ' s novel " Spock ' s World " , Lieutenant Meshav , a Sulamid , is described as having " " an octocameral brain , which meant s / he might manifest up to eight personalities . S / he tried to restrain herself from doing this too often , citing ( as Jim had heard it put it ) ' pity for the poor single - mindeds . ' All the same , a poker game with Meshav was an interesting experience , especially considering that one personality was completely capable of hiding the contents of one ' s hand from all the others . . . not to mention from any opponent . " " The comic - book story " " involves several personalities harbored by Jean - Luc Picard in addition to his own ; Sarek , Kamin , and Locutus of Borg .