Split

split ( n., v., adj.)
Other forms	splitting (v.)
Synonyms	forming
Applies to	systems, headmates, system functions
Origin	Psychiatric term[medical citation needed]

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).

Any type of stress can cause a split and splits can create any number of headmates from one event. A "split" may refer to the new headmate themself too, or the newly split headmate in relationship to their precursor.

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 may be distinguished into reductive and non-reductive, depending on whether or not an existing member was broken apart. Examples of reductive splits include shattering and fracturing. The breaking member may still exist after the split.

Non-reductive formation may still be stress-related, for example by headmates being built from fragments.

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.

In polyfragmented systems, splitting may occur more frequently or in specific complex patterns, with several members splitting at a time.

If several members split at the same time or due to the same immediate cause, they may be regarded as splitlings, form partners, or homologousor.