New Essential Guide to Alien Species - Condition

In the Quermian physiology, however, there is a flaw that is not seen in their Xexto cousins. Because their mental abilities have been genetically altered, some Quermians are known to develop sudden psychoses, such as obsessive compulsive disorder, dissociative identity disorder, and the like. The development of the dissociative identity disorder often happens when one of their brains takes on one personality while their second takes on another—causing an internal battle in the individual.

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While most Quermians do not develop such disabling disorders as those mentioned, they will usually have at least one mild phobia or minor compulsion, which will not be debilitating. These sorts of mental conditions seem to be well contained among Quermians who follow the Jedi path, as the training coaches them to deal with fears and habitual behaviors