Christie biographer Laura Thompson provides an alternative view that Christie disappeared during a nervous breakdown, conscious of her actions but not in emotional control of herself.
Within the framework of environmental contradictions, the narratives of these women revealed a surprisingly shared sense of inevitability, a perception that the events of life are beyond the control of the individual, which accounts for the consistency in the way in which Issei women, different and individual in many ways, seem to have structured their emotions—and this quality of emotional control was passed to their Nisei children.
It may also be involved in some cognitive functions such as attention and language as well as emotional control such as regulating fear and pleasure responses, but its movement-related functions are the most solidly established.
T'Pol states that paranoia and homicidal rage were common on Vulcan before the adoption of Surak's code of emotional control.
When Jara did not return his affections, Tuvok's jealousy caused him to be expelled from school and resulted in his parents sending him to the Vulcan master (Joseph Ruskin) to learn emotional control.
There is a fair amount of evidence to suggest that he never entirely gained emotional control, and he feels bitterness over his Vulcan heritage.
Her emotions became even more difficult to control following an exposure to trellium ore, a toxic substance which damaged the part of her brain responsible for emotional control.
Although T'Pol subsequently overcame her addiction, Phlox determined that she had permanently damaged her brain, and as a result might never achieve the same level of emotional control she once had.
Post-Brand New Day, a further enhancement of his telepathy granted him the power of telepathically compelling humans to act out their primal urges, by suppressing emotional control in their amygdala (the "lizard brain").
Other risk factors that may be evident during childhood and adolescence include, aggressive or troublesome behavior, language delays or impairments, lack of emotional control (learning to control one's anger), and cruelty to animals.