Split

For a headmate's or dæmon's appearance, see soma and form respectivelyundefined:

Splitting is the process of the brain forming new headmates through external stress, usually breaking up an existing headmate into multiple (although the origins of some splits may be unknown).

Anything can cause a split — violence, school stress, intrapersonal drama, abuse, flashbacks, etc. — and splits can cause one, two, five, or ten headmates from one event. A "split" may refer to the new headmate themself too.

Other Uses
The term splitting also has other uses, primarily in Borderline Personality Disorder, where it refers to black and white thinking (seeing things in a positive/negative binary), particularly within the context of a sudden change in how an individual with BPD views another person or thing.

Related Terms
Splitting is primarily seen in adaptive and/or traumagenic systems. It's different than walk-ins, because they come from outside of the system, and created headmates (like thoughtforms) are not usually considered splits either.

Splitting typically happens more frequently and creates more headmates in polyfragmented systems.