Dahlmorians have a similar mind of that of a vulcan from the star trek franchise. But with some distinguishing features. Unlike humans, dahlmorians don't care for emotions but some times show happiness or misery in some conditions.
Also, the term "Creature" is used when a dahlmorian becomes feral. Meaning they lost their sanity and their self being, slowly becoming a rabid animal. Creatures are commonly seen in research facilities as psychologists induce this state into their patients and study the results.
Usually, creatures are used as test subject for the DSF to test out new methods of bio weapon war fare. Even though containing these dahl are complicated because they tend to attack who ever they come across.
In order to turn a dahlmorian feral, they must be induced to several circumstances that would cause insanity for most animals. Psychologists just give their subjects an injection that ravages on the subjects mind until they lose them selfs. Also, torturing works as well.
Some dahl have a mental condition that causes them to be more vulnerable to emotional circumstances. For example, if you were to present a gift to a dahl with this condition, he or she would feel happiness while if you present a normal dahl a gift, they won't really feel anything. These dahlmorians are more vulnerable to becoming feral in certain conditions that could drive humans insane. So they aren't allowed to work in the DSF cause the work will drive them mad.