[s7e2] Shock To The System Instant

In an episode also titled Barry Allen receives a literal and figurative "shock to the system":

During a surgery, Cristina experiences a severe post-traumatic breakdown on the operating room floor. This leads her to question her place in the hospital and eventually give her wedding ring back to Owen.

Barry gains the ability of "speed-thinking" thanks to the Artificial Speed Force, but it begins to strip away his humanity, making him cold and calculating.

Seeing the damage his logic has caused provides the emotional "shock" needed to break the Speed Force's hold and return his feelings. Other Shows with this Episode Title

"Grey's Anatomy" Shock to the System (TV Episode 2010) - IMDb