Yes, Tuvok, the Vulcan chief of security in Star Trek: Voyager, does experience symptoms similar to post-traumatic stress disorder (PTSD) in some episodes of the series. As a Vulcan, he is known for suppressing emotions, but certain situations and events throughout the series expose him to intense emotional experiences that impact him profoundly.
One notable episode where Tuvok grapples with PTSD-like symptoms is in the episode titled "Flashback" (Season 3, Episode 2). In this episode, Tuvok experiences flashbacks related to his involvement in an important historical event known as the "Khitomer Massacre." This traumatic memory resurfaces due to a mind-meld with Captain Jean-Luc Picard of the USS Enterprise-D. Tuvok experiences emotional turmoil and must confront the suppressed emotions he has carried for many years.
Additionally, in the episode "Gravity" (Season 5, Episode 13), Tuvok experiences neurological degeneration due to a condition called "pon farr," which is a biological and emotional mating instinct that affects Vulcans. During this time, Tuvok's emotional control is compromised, leading to erratic behavior and heightened emotions, which are in stark contrast to his usual demeanor.
Though not explicitly referred to as PTSD in the series, Tuvok's experiences in these episodes showcase the complexity of emotional struggles for a character who typically keeps his emotions in check. It highlights how trauma and intense emotional experiences can affect even a Vulcan, emphasizing the human-like struggles that he faces beneath his logical exterior.