Has any member of a crew in Star Trek ever suffered from PTSD? They either watch someone die in front of their eyes or kill someone (or worse, are bound by the prime directive to do nothing to prevent death) in every other episode. Is this ever addressed on screen?
The Original Series
- Commodore Decker, sole survivor of the USS Constellation (Season 2 : The Doomsday Machine)
The Next Generation
- Jean-Luc Picard suffers from PTSD from being assimilated. (Season 3 and 4 : The Best of Both Worlds and Family)
- Miles O'Brien suffers from PTSD from the war with Cardassia and it's explored a bit in TNG and DS9. (Season 4 : The Wounded)
- Geordie LaForge suffers from PTSD from when he was brain washed and made into a manchurian candidate type assassin by the Romulans. (Season 4 : The Mind's Eye)
- Jean-Luc Picard suffers from PTSD from being tortured by Cardassians. The famous "How many lights are there" episode. (Season 6 : Chain of Command)
- Troi suffers from PTSD from being mentally sexually assaulted. (Season 5 : Violations)
- Virtually the entire cast of TNG suffers from PTSD from being dragged into another space-time and being experimented on. (Season 6 : Schisms)
- William Riker is traumatized by switching between 2 realities (A Hospital and the Enterprise) back and forth. (Season 6 : Frame of Mind)
Deep Space Nine
- Benjamin Sisko suffers from PTSD from the battle of Wolf-359 when his ship was blown up. (Season 1 : Emissary)
- Miles O'Brien is sentenced to 20 years in a virtual jail that is played out in seconds. (Season 4 : Hard Time)
- Nog suffers from PTSD from the of AR-558. (Season 7 : The Siege of AR-558 and It's Only a Paper Moon)
- Chakotay suffers from PTSD from being brainwashed to fight in an alien war (Season 4 : Nemesis)
- Seven of Nine suffers from PTSD from being assimilated as a child. (Season 4 : The Raven)
- Neelix suffers from PTSD from dying. (Season 4 : Mortal Coil)
- Seven of Nine suffers from PTSD from being knocked out and experimented on. (Season 4 : Retrospect)
- Neelix suffers from PTSD from the Nakkan massacre (Season 6 : Memorial)
- The entire crew of Voyager suffers from PTSD from reliving the war memories of an extinct species. (Season 6 : Memorial)
- Marla Gilmore suffers from PTSD from being flung into the Delta Quadrant and then attacked repeatedly by those etherial creatures the Equinox was using to power their Warp Drive. (Season 5 and 6 : Equinox)
- T'Pol suffers from PTSD from being Mind Melded forcibly. (Season 1 : Fusion)
- Trip can't sleep at all for much of Season 3 after his hometown was destroyed and sister killed; this leads to various plot points, including his entire relationship with T'Pol.
There are many more that I can't think of right at the moment, but an important thing to remember is that PTSD is generally long lasting (but can be short lived), but we almost never see these things brought up again in any future episodes. The closest we get to seeing a long term thing is Miles O'Brien who repeatedly shows signs of PTSD when he interacts with Cardassians and through avoidance of combat scenarios. Picard pretty much shows no signs save for during First Contact when he loses it and smashes the Enterprise models. Seven shows minor signs as does Sisko, but we're left with mainly with the impression that PTSD seems to be readily curable in the Star Trek universe or the characters experience so many traumatic events that it becomes white noise for them.
"It's Only a Paper Moon" centers on Nog experiencing PTSD following the events of "The Siege of AR-558" (episodes 7x10 and 7x08, respectively, of Star Trek: Deep Space Nine). He spends much of the episode in DS9's equivalent of the holodeck. While PTSD is not (to my memory) specifically mentioned in the episode itself, Memory Alpha provides this quote from David Mack:
"...the major force on 'Paper Moon' was Ron Moore. John Ordover and I had pitched a story years before that bore only a passing resemblance to the episode that it became. By the time the DS9 writing staff had finished 'revising' our original pitch, the basic idea was in place. Ron asked us to draft a full outline based on the premise of Nog coming home after "The Siege of AR-558" with a cybernetic leg, and seeking solace in the Vic Fontaine holoprogram. What John and I added to that premise was the reason why Nog was in the holosuite: PTSD – post-traumatic stress disorder. Essentially, Nog had confronted the truth of his own mortality, and it had destroyed his youthful illusions about being invulnerable and about the 'glory' or 'heroism' of warfare. But the truth is that it was Ron Moore who took that idea and put it into words and images, giving it such resonance and honesty. It was also Ron’s courage as a writer that enabled two supporting cast-members to become the leads for an episode. I am simply honoured to have been part of the process"
The DS9 episode Hard Time is the one that came to mind (it deals with PTSD on point). O'Brien is sentenced to a "20 year" prison term. The technology the species possesses causes him to live 20 years in his mind in a few seconds. O'Brien experiences what is the very definition of PTSD due to his "time" in prison. He lashes out at people and becomes deeply depressed over this. Towards the end of the episode tries to commit suicide.
Bashir arrives and tries to talk O'Brien out of killing himself. O'Brien says he cannot go on living when he is a threat to his family and all his friends. The man he was is gone, and all that's left is a dangerous monster. He confesses his worst crime: after almost twenty years, he found that Ee'char had been hoarding food without telling him, and killed him in a rage – before he realized that the food was for both of them. Miles Edward O'Brien, an "evolved" Human of the 24th century, gave into bestial rage and murdered his best friend, for nothing.
Bashir tells him he's wrong; the fact that he feels remorse over killing Ee'char proves that he is still a decent Human being, not a monster. His captors tried to strip away his Humanity; they may have succeeded for a moment, but if O'Brien takes his own life, the Agrathi will have succeeded in destroying a good man. Over Bashir's shoulder, O'Brien is surprised to see Ee'char, smiling at him, without reproach. Ee'char tells his friend to "be well," and walks away, disappearing. O'Brien lowers the phaser, and Bashir takes it away.
Walking O'Brien back to his quarters, Bashir prescribes a medication that will take the edge off his depression and stop him from having any more hallucinations. However, the false memories cannot be removed, and O'Brien will have to come to terms with them on his own. Bashir convinces him to resume counseling sessions, and O'Brien thanks his best friend for all his help.
The accepted answer is great, but it is missing the Frame of Mind episode (Season 6, Episode 21) where:
Riker thinks he is losing his mind when reality keeps shifting between an alien hospital and the Enterprise, where he is rehearsing a play.
Basically, Riker is “losing his mind” because he was kidnapped and—essentially tortured—for information; bold emphasis is mine:
Picard explains what really happened, and Riker remembers it. He was attacked from behind and abducted in an alley. As he tried to fight them off with the ceremonial knife, the nisroh Worf gave him, Riker's attackers injected him with something. Picard concludes that they were attempting to extract strategic information from him.
Troi explains that everything he saw was a defense mechanism, which allowed his mind to keep its sanity. Most notably, the bleeding coming out of his head exactly corresponded to the point the neural drain device was attached to his head; it was his body warning him he was being injured. Picard advises Riker to get some rest but he has something he must do first. Later on, Riker returns to the stage where he had previously performed in the play. Crusher tells him that they plan on striking the set in the morning, but he decides to strike the set himself; he couldn't sleep knowing it was still up.
That last sentence is a key for me: I remember being a bit stunned at the end of the episode when Riker fully realized what had happened and had to physically destroy the stage set. Which to me is a very clear and simple act of someone dealing with the need for “closure” in PTSD.