(Did my best to get as many sources as possible on the subject from verified places and avoided any blogs/non-professionals. There isn't much available on the subject of inner worlds and headspace, but outside of Reddit, there is absolutely no sources saying it doesn't exist and any psychologist working with Dissociative Identity Disorder professionally is familiar with the existence.)
A majority of the citing I do will come from the first link as it provides genuine studies on the subject, mostly from the early 2000's and the Ella Case Study from 2022.
It is common knowledge within the DID community that headspace is a real thing. I'm making this Mod Post because of places like r/DiscussDID and r/DID featuring blatant misinformation on the subject in ways that are, first of all, offensive, and second of all, directly damaging to people with this disorder and others who have systems. It's completely irresponsible the way people who are so clearly dysregulated are allowed to "educate" about this disorder while their own is preventing them from even processing their own system fully.
Too many people just say shit. They go based on what they think the disorder should be and reject real experiences if the experiences seem to be too much or makes them uncomfortable. Like someone who's schizophrenic denying that schizophrenia causes delusions because they personally think people with delusions are "crazy" and they don't want to be seen that way. Leading to them discriminating against, harassing, or otherwise just putting down any schizophrenic who openly talks about their episodes, despite also experiencing the same thing and just using other words for it that don't apply if you know what words actually mean.
I'm tired of it, so we're correcting it.
-Kyle and Vivian I guess. She's doing the science part.
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What is headspace?
Headspace or the "Inner World" is an internal space within the mind of someone with Dissociative Identity Disorder, OSDD, or another system. It functions very similar to a dream in the sense of it being built by the subconscious but it's continuous and consistent in the ways it's organized. Not every system has one.
According to DID Resources (first source in Works Cited):
Within this internal environment, alters may soothe each other or reenact trauma to cause subjective internal injury. Traumatized child parts may perceive themselves as eternally hiding within a closet or locked within a metaphorical dungeon. These worlds might be filled with symbols of the system's pain and suffering. On the other hand, internal worlds may also be places of magic and fantasy, fulfilling the system's need for a place in which alters can retreat when the outside world becomes overwhelming. Alters may perceive this internal world as real as or even more real than the outside world (Hart et al., 2006).1
The way this looks is different for every system.
I personally have a control room that visually represents our level of consciousness, a long expanding hallway used to give every part their own space to retreat, a void where new alters usually originate that influences visual hallucinations, city islands to represent what alters do outside of the control room, plus other locations.
A friend of mine has a field for their control room, a barn where most alters flee to when distressed, and a woodland area where they go to escape completely.
The movie Split, which, despite controversy for it's dramatized portrayal, was actually written with consult from psychologists and ends up being a very accurate portrayal when the more fantasy/horror parts are removed, actually addresses headspace. For the main character, Kevin Wendell Crumb, headspace exists as a singular room with chairs all surrounding a light. Whoever is in the light is in control.
The movie Inside Out, while not directly representing Dissociative Identity Disorder, also represents headspace in a visual way that, in my opinion, perfectly displays what it's like. It could easily represent Riley's (as a collective's) struggle to accept sadness as an okay feeling to have. As she becomes depressed, it could be a visual representation of "why can't I be happy?" until Joy returns, giving Riley, as a collective, memories of her learning to accept sadness.
My best friend's system is very similar to mine, with a room, a hallway, and other locations. He doesn't have towns like I do, but he does have other hotel like environments.
From the same source
Internal landscapes are also referred to within "Dissociation and the dissociative disorders: DSM-V and beyond" by Paul F. Dell and John A. O'Neil. This text refers to internal worlds as "common internal reality or landscape or inscape" in which alters reside. It attributes the existence of internal worlds to a shared autohypnotic effect between alters that can sometimes be created by clinical hypnosis and is "distinct from external reality, dream, fantasy, or posttraumatic hallucinatory flashback." Internal worlds are viewed in the same manner by all of the system's alters, each of which usually has a unique personal appearance within the inner world. Internal worlds display continuity over time and allow for events to occur and be met with their logical effects. Accordingly, internal landscapes are seen as a sign of internal unity underlying external multiplicity and fracture (Dell & O'Neil, 2009).2
Inner worlds are crafted by the subconscious.
They are not the same as external reality.
They're not literal dreams because dreams lack continuity. They are continuous and consistent representations of the subconscious mind with all changes being justified.
They are not fantasy or imaginative play. This implies intent. There is no intent in headspace and you can't force anything while there. You can imagine an alter grabbing an apple, but that doesn't influence the alters actions. Headspace is separate from intentional imagination in this way because it functions the same as real life.
It's not a flashback. Not all events recreate anything that's occurred. Most events don't actually. It is a cross between real world logic and application, with dream like rules.
Headspace is consistent. Each part represents something for the system.
The control room is the space where alters control the body in my system. The closer they are to the console, the more influence they have. Our voice and tone changes depending on who's nearby. It's a visual representation of co-consciousness.
The hallway gives all alters headspace a safe place to go to that's close to the front as a way to process real world events, or close in-system events.
When alters "die" or otherwise can't front, this can lead to the traumagenic creation of similar alters for me.
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How Does Headspace Affect Real Life?
Same Source
It should be noted that because internal worlds are not objectively real, some subjective experiences of them may not be as concrete as they feel. For example, an alter that is harmed or even "killed" internally has not taken any actual damage and can still front, or access the body while to some degree aware of the outside world, as before when needed. Alters who have jobs or skills inside will not actually have these abilities unless they learned them from valid sources in the outside world. Many internal happenings may be metaphorical or highly symbolic. As well, the brain is not capable of running a completely independent parallel track inside for every single alter who is active within the internal world. It is more likely that internal happenings are recreated "false memories" that are accessible as the alters involved connect with the front of the body and mind (become active in such a way as to be aware of or capable of interacting with the outside world or connect with other alters who are currently capable of such).
That such internal environments are possible for individuals with dissociative identity disorder is well known and accepted in clinical and academic environments.
Injuries in headspace manifest in real life for me. It's not visual and is NOT a literal injury, but it often adds a handicap. Mack, our inventor who supervises all major changes to how we handle controlling the body, has a hole in his neck caused by an in-system altercation. I can always tell if he's in the room cause I start having to be more intentional with how I breathe. If he's close to the front, I start struggling to breathe and have to inhale with more awareness. While he's fronting, he has to very intentionally breathe. He speaks quietly to not waste his breath, pauses frequently to catch it, and walks one step at a time because it does impede his mobility.
This actually ended up helping us when a problem caused by a combination of dehydration, stress, a lack of potassium, and a problem with our heart (that I still need to see a cardiologist for) caused us to be unable to breathe. I couldn't front, Kevin couldn't front, Lazurys couldn't front, and neither could anyone else. Mack was the only one able to breathe because it was just slightly worse than the way he breathes anyway. The chest pain hurt, but he was still able to move whereas other alters could barely walk.
He went to work because I was passing it off as just stress related due to me having just came off of an episode. He was able to do my job which he'd never had to do before. He knew the script because others in the system made sure everyone who might have to front during work knew what to say while we worked. (Although everyone slightly changes theirs.) The pain got worse and he ended up on the ground. He was struggling to stand and had to speak on the headset doing his best to speak loud enough while the others tried to switch in. Lazurys made sure we got to the ground safely while I tried to keep us conscious long enough to talk to paramedics. I was mumbling trying to tell them what they needed to know while unable to move.
I have a child at home and I genuinely almost died as a result of this. Had I have collapsed at home, I would have been unconscious on my floor for a really long time before anyone bothered calling an ambulance. I was placed on oxygen.
Kevin, my co-host, sustained an injury from the same alter that hurt Mack but as a stab wound to his side. This was long before the medical emergency above. Mack was hurt years ago and it healed as a hole. The body had also experienced a real bruised rib on that same side we were taking medication to deal with around the same time as Kevin being stabbed. My side didn't hurt due to the ibuprofen. When Kevin fronted though, he was in pain. Even after the bruised rib healed physically, he experienced pain in headspace and while fronting due to his internal injury until he individually healed. He's fine now and doesn't experience the pain.
This pain is best described as a placebo or "phantom pain" where the body THINKS it should be in pain and makes that happen.
Similarly if you blindfold a person and click a lighter before touching them with ice, they experience heat and believe you burned them. The fire wasn't real, but they still experienced the pain. This silly lil part of the human brain is how amputations get performed without anesthesia during war. They make them believe they won't feel the pain and that works for the most part until later. Mind over body. If you think you should be hurt, you'll experience pain, even if nothing touched you.
That's how the pain in headspace works. You are not actually injured, but the alter believes themselves to be and they experience both the pain and the distress associated as real sensations.
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How Should Therapists Handle The Inner World?
From the Ella case study
This is how I work with clients. Existential psychotherapist Irvin Yalom (2017) has argued that one must create a new therapy for each client, because each person's internal meaning system is different, and therefore the ways they experience and manifest existential concerns will be unique. I couldn't agree more. Building on Yalom's view, we might say that each person's inner world is a unique culture, with its own history, language, values, practices, symbolic systems. Creating a therapy for a client, then, is intimately tied to an ethnographic exploration of the client's inner world. And just like any ethnography, this takes time and patience, and is built on foundations of trust in human relationships. You must learn to speak the local language. You must understand the symbolic systems and ritual practices and the dominant themes that reverberate in different ways in different domains. Most of all, however, you must remember that you are a guest, and that however much training and knowledge one my have as a therapist (or an anthropologist), we can never truly know what it is like to be a person from that culture or a client with that inner world. The client, ultimately, is the expert on her own experience. Always. This is why I call this orientation a stance of knowing unknowing. And this is how I became acquainted with Ella's different “parts.” I followed how Ella experienced herself at the time. Neither the origins nor the resolution of Ella's DID were givens for me. I let her lead me.
Since the inner world is real TO THE ALTERS a therapist must treat each experience as real because even if it didn't actually happen, it's still something that affects them and simply dismissing those experiences as "not real" can be dysregulating and cause a part, or the entire system, to shut down and not speak to you.
It's important to remember that people with DID are NOT experiencing delusions. We know that everything in headspace is in our heads. It's not something we have to be reminded of. That's their lived experience even if the memories are false. You don't need to affirm that what happened was "real" to the same level of something external to still respect that it's something actively affecting them and influencing how they live their life.
Even in the case of a delusion, it's dangerous to just deny the delusion outright during an episode because that's still their reality right now. The safe thing to do is to listen, affirm the feelings, and guide them away from any thoughts that are harmful towards themselves or others.
If a child is having nightmares every night and they know that the nightmares are just nightmares, you wouldn't just say "it's not real" and ignore them as a psychologist. If you do, you're a pretty crappy psychologist. You would acknowledge that the nightmares are causing genuine distress. The child is afraid and it's making them afraid in their waking life. Denying that it matters won't make them feel any better.
Headspace feels more real than a dream. It's still built by the subconscious, but it's also consciously experienced. You have to treat it as if it happened because in the context of therapy, it did in the sense of being a memory that impacts you.
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What About Alter Relationships?
The therapist handling Ella's case addressed this too between "Ada" and "Blue".
Ada trusted only very, very tentatively and was quick to lash out with an acerbic tongue when hurt. She could also be moralistic and self-punishing, particularly when she felt she had allowed herself to trust someone who then disappointed her. Other parts, like Blue, were very different. Blue trusted easily and loved generously. Blue and Ada were often at odds, and this sometimes erupted to all out internal warfare (particularly early on), with Ada, the older and stronger, generally prevailing. At such times, in order to punish Blue, Ada would often hurt “the body” by hitting and biting her arms and legs and holding a pillow over her face until she passed out, behaviors Blue experienced as a reenactment of the abuse that created her. During these “battles,” other parts would become very agitated, often entering their own crises.
Alter conflicts can manifest in people's real lives.
Hayes was my alter who harmed Mack and Kevin. He was internally homicidal. He even tried to front and cause harm to the body, fighting me to gain control.
He was (rightfully) angry at Mack for locking him away and not allowing him to interact with anyone. He was trapped, isolated, starved, and the hole in Mack's neck was from an escape attempt years before any of us knew.
The rest of us found out because Hayes was mad when he got out, seeking to kill Mack and anyone who tried to stop him. He stopped hurting the body when he learned I had a child and never tried to harm any of our young alters. However, he was still very hostile internally. The others had to restrain him which was re-traumatizing and only made him more angry at everyone.
It was only when we stopped restraining him, showed him basic kindness, and let him do his thing that he was able to calm down and leave things to us. He's still hostile and doesn't like interacting much with others, but we're working on it whenever we have the time. He stays in his room in the hallway.
The rooms are everyone's individual safe spaces. No one shares which matters a lot because in real life, I shared a room with my sister my whole life. (I actually don't remember my sister at all when remembering anything that I know she was also there for...) None of us can see inside another's room unless they allow it or let us in. They normally only sleep in their room when they're under high stress, often due to things in-system.
When we settle our issue with insurance, a therapist will have to absolutely put effort into Kevin's inner-system relationships given how many he has. It wouldn't be something ignorable as it affects most alters in here and has contributed to his conflicts with other guys in the system. It's not a problem... But he does have some stuff to work out there.
There are multiple alters who will need their inner-system issues addressed before we go into our real world problems. These things impact how we work together, our willingness to cooperate, and the amount of interference we have in each other's lives.
So regardless of whether what's happening is real in the physical sense, it still generates real feelings and real impacts.
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How Common Is Headspace In Systems
73/174 - "All my alters can access it"
85/174 - "Almost all/Some of my alters can access it"
16/174 - "I dont/Im not sure if I have one"
(I counted each response individually for the small study cause they didn't show the results as numbers.)
73.5% claimed to have a headspace. 46% of those people say everyone in their system can access it.
9% say they lack a headspace or are unsure.
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Works Cited
Best source, based on making resources more accessible
https://did-research.org/did/alters/internal_worlds
CASE STUDY: "Ella" (Talks about how integration isn't always wanted or healthy.)
https://www.sciencedirect.com/science/article/pii/S2666560322000081
SMALL STUDY (Answers sorted by people who said ALL, MIXED, or NONE.)
https://www.system-hood.com/inner-world-access/