Multiple Personalities, Blindness and the Brain

By Neuroskeptic | November 20, 2015 2:06 pm

A new paper reports the fascinating and perplexing case of a woman who reported that she was host to multiple personalities – some of whom were completely blind. The paper is called Sight and blindness in the same person: gating in the visual system, authored by German psychologists Hans Strasburger and Bruno Waldvogel.


The patient in this case, “B. T.”, aged 33, has a diagnosis of dissociative identity disorder (DID), a condition formerly known as multiple personality disorder (MPD). B. T. originally became blind (or seemingly so) following an accident at the age of 20. Her eyes were not damaged in the accident; instead, doctors attributed her loss of vision to brain damage: cortical blindness.

Years later, B. T. entered psychotherapy for her DID. In therapy, she manifested ten different identities or personalities, which differed in “name, reported age, gender, attitudes, voice, gesture, facial expressions” and other characteristics. Such a multiplicity of selves is not uncommon in DID patients.

But in B. T.’s fourth year in therapy, something unexpected happened: she regained her sight – but only some of the time. Some of B. T.’s personalities became able to see, while others remained blind. Strasburger and Waldvogel write that “Sighted and blind states could alternate within seconds.”

Now, by itself, this would be an odd psychological case study, but rather difficult to interpret, because the whole case would revolve around B. T.’s self-reports of her blindness. For instance, one interpretation would be that B. T. was malingering, for instance – that she had “made up” the blindness, and possibly also the extra personalities.

But Strasburger and Waldvogel present some remarkable evidence that seems to exclude malingering as a possibility: they show that when B. T. was “blind”, her brain actually didn’t respond to visual stimuli. To do this, they used EEG to measure visual evoked potentials (VEPs). A VEP is an electrical response generated in the visual cortex of the brain in response to stimulation. The absence of VEPs is suggestive of blindness.

Strasburger and Waldvogel show that B. T.’s brain generates normal VEPs when she’s in a “sighted” personality state, but that when she’s “blind”, there is a total absence of VEPs:


In the “sighted” condition, a sharp downwards peak is visible at approximately 100 milliseconds after the stimulus is presented. But the same stimulus evokes no detectable response in the “blind” condition.

This is really quite something.

The authors say that B. T.’s blindness must have a “psychogenic” origin, because of how quickly it comes and goes. No known biological process could cause such a rapid alternation between blindness and perfect vision (recall that B. T. can go from one state to another “within seconds.”)

So what could be going on? Strasburger and Waldvogel say that the answer may lie in processes that exist in the normal brain to temporarily “block out” visual input:

The phenomenon of a temporary suppression of the afferent neural signal in the healthy human that is reversible at any time is more common than it would first appear. Images of the two eyes that contradict each other temporarily, for example, when squinting or with dichoptic stimulation, lead to a transient, partial or full, suppression of one eye’s image…

So brain mechanisms are present that allow modulation of the incoming information, acting on either the entire visual field or some parts thereof.

On this view, B. T. not only genuinely believes she is blind – she really is blind (some of the time.) Some neural pathway is active which prevents visual information from reaching her brain. Her blindness is “psychogenic” but also very real.

Are there any more prosaic explanations? My first thought on reading this paper was ‘what if she’s just closing her eyes, or looking away?’, but Strasburger and Waldvogel say that an experienced VEP tester was observing her during the procedure to make sure she was looking at the stimuli. Furthermore, they note that B. T. got a VEP test when she first went blind, and that infrared eye-tracking was used to verify that she was looking at the stimuli. No VEPs were detected that time.

The authors do note, however, that it’s theoretically possible that B. T. could have been (consciously or unconsciously) de-focussing her eyes in such a way that all visual input was blurry. They note that this would not be easy for an observer to spot, but they say that it would have to be an extreme level of de-focussing to blur out the stimuli used in a VEP test, which are large and very bright. Still, I would want some further testing to exclude this possibility before I was convinced by the “neural gating” hypothesis.

Link: also blogged at BrainDecoder.

ResearchBlogging.orgStrasburger H, & Waldvogel B (2015). Sight and blindness in the same person: gating in the visual system. PsyCh Journal PMID: 26468893

CATEGORIZED UNDER: EEG, mental health, papers, select, Top Posts
  • Mindbody Medic

    Fascinating stuff, thanks. Has anyone repeated the experiment on perceptual adaptation of vision?
    George Stratton I believe and someone else claimed that after wearing inverted sight glasses they flipped their visual field after a week or so of constant use. To be clear they wore the inverted glasses and kept having patches of normal vision, then after more time the visual field flipped entirely. When they removed the glasses their normal vision was now upside down.

    I’d love to see robust evidence of such a thing occurring.

  • OWilson

    Nice to know that DID has replaced MPD.

    Gotta keep up to date with these syndromes in case at some point in the future they declare it “terminal” and us carriers can be eradicated!

    They’ve already declared climate prediction skeptics “insane” so it’s always best to stay up to date!

    One never knows who or when they will be calling for your demise.

    • Laren Ganer

      … … … What?

  • Rolf Degen

    If this were to be confirmed, it would settle the debate about whether cognition does affect perception at all, which some deny:

    I would be still more impressed if one of the personalities would suffer from Cotard’s-Syndrome, thinking she was brain dead – and show no EEG at all.

  • davidkennerly

    Interesting that the magazine uncritically reported DID as a condition that actually exists.

    • Neuroskeptic

      I never said that DID patients really have multiple personalities, I only said that they report that they do and behave accordingly. I think DID is probably a culture-bound syndrome that involves, so to speak, an acted-upon belief in multiple personalities.

      • davidkennerly

        Fair enough and, when described that way, I think you are right on the money. I do think it would be valuable to allude to the controversies which DID arouses within the professional community but I realize that not all pieces can serve all purposes. What really concerns me is the effect of (what appears to be) a professional endorsement of DID, within the context of multiple personalities, has upon society much of which tends not to have gotten the later memo that Sybil, or more lately, Tara, are heaving piles of pseudo-science. These unreceived revelations, like the ones debunking recovered memory, infiltrate society and form consequences in real-world policies, laws, and discourse.

    • theambler

      “Years later, B. T. entered psychotherapy for her DID. In therapy, she manifested ten different identities or personalities”

      This bit caught my eye. When a patient starts having multiple personalities in therapy, it’s time to presume nonsense. I am very sceptical of this finding as a result of this.

      • Laren Ganer

        Your interpretation of that sentence is a little off. It’s not intending to say the patient started having different identities for the very first time during therapy. It’s intending to say that in the course of therapy, ten different previously existing identities were identified.

        Think of it this way: “Alice admitted herself to the hospital for her infections. In treatment, she manifested ten different strains of bacterial infection.”

        Alice sought treatment because she had symptoms of illness. During treatment, they were able to discern the specific number and types of infections she was carrying. Diagnosis did not cause her to have the infections, it simply identified them.

        • BridgetBishop

          Um, the only way people get these personalities is to go to a therapist who trains them in roleplay. They don’t exist before therapy of DID true believer therapists. The therapists who believe this stuff have done heaps of damage.

          • Laren Ganer

            Late reply, but only just now saw your reply. Strange. Anyway, no, I can tell you from firsthand experience that the personalities do not first develop in therapy. They’re certainly specifically engaged in therapy, of course.

            I’m the daughter of someone with DID, and when I was a child (before any of us knew MPD/DID was a thing), I could see my mother ‘switch’. Since I was only a child, I didn’t know what was happening; all I knew was that my mom wasn’t acting like my mom anymore. She was acting like another person.

            When I got older, I rationalized this behavior by telling myself that everyone has multiple facets to their personality, maybe my mom’s very sudden and complete shifts to other people was just part of that.

            However, in spite of us not knowing that DID existed, and in spite of her not having gone to a therapist, she was manifesting multiple identities. Without realizing they were separate personalities, I even got to know them — mostly as a coping mechanism, so I would know what to expect. Because when someone can switch personalities like that, you really can never know what kind of reaction you’re going to get from that person.

            Many years later, when she finally saw a therapist and was diagnosed, we all went, ‘Ohhhhh… yeah.’ I never questioned the diagnosis, since I grew up witnessing it. Sometimes it was subtle, other times it was blaringly obvious and sudden. She’d look away from me and a moment later look back, and she wasn’t ‘herself’ anymore.

            Years down the road, after she’d made some progress on ‘integration’ as well as a greater self-awareness and awareness of dissociation as well as identifying triggers, I was able to spend time with just the one person who was my mom. It was a wholly different experience.

            Sooooo, yeah, no. While I agree that some therapists can and have created a problem for their patients, this is not the case with 100% of the diagnoses. There are some people who legitimately have multiple distinct whole identities, who had them before they saw a therapist.

            And just to head off the ‘maybe she was doing this because she knew of it via pop culture’ thing, first of all god no one would want to do that to their family on purpose. It was traumatizing for her children, and she would never purposefully do that. When she was just herself, she was a really good mom. Second of all, we were one of those super religious families who didn’t watch TV or movies, and the majority of our social interaction was with others who followed the same path. Plus, this was long enough ago that the disorder had not seeped into so many aspects of popular culture. There was that famous movie, but other than that, not much.

            So, it didn’t come from pop culture, it didn’t come from a therapist. It came from an internal coping mechanism she developed and relied upon as a child enduring trauma. And I know she couldn’t possibly be the only one.

          • BridgetBishop


            Personal stories are difficult to discuss. All I can say, there are a million reasons why your mom could change her behavior. The therapy itself has no basis in reality. There is NO science behind it. There is simply no evidence that trauma results in the repression of memory…all studies point to the opposite. Flash backs are often the outcome of trauma – memories that cannot be forgotten. Trauma also aids learning. There are experiments supporting this.

            As for “some” therapists. If a drug was out on the market that resulted in only 35% of the population adopting suicidal behavior and ruining the lives of multiple people with whom they came in contact, what would happen? It would be pulled off the market! This therapy needs to be pulled off the market. The number of documented cases where peoples health and lives have been negatively impacted DID therapy is substantial.

            There are other safer TESTED ways of helping people who change their behavior or have encountered trauma in their lives. This therapy ruins lives. From what you say, I’m glad your mom wasn’t one of them. (I’ve known of several religious families who were torn apart by this diagnosis. For some reason religious counselors love this diagnosis, and end up convincing women of all sorts of things. Many of these women have realized it was the therapy driving their memories and have tried to put their lives back together with their families post-therapy. It’s difficult to erase the damage this therapy does.)

            And, thank you for the civil response. I’ve found this subject often results in inflammatory responses…as you might note.

          • Laren Ganer

            I completely understand that personal stories are not particularly, well, data, since anecdote is not the singular form of that word. 😉

            Thankfully for all of us (because I’ve seen one of these types a few times because it was “free” and it was AWFUL), she did not see a religious therapist. It was just a regular one.

            I think that one aspect of this that I guess I forget is that apparently “memory repression” is a central part of people’s concept of DID. In my mother’s case, that’s not how it worked. She didn’t *repress* any memories. It was more like, they were nicely compartmentalized for her everyday-life convenience. If anything, sometimes it was more akin to state-dependent memory, only the state she was in was a dissociated one.

            The thing about memories of trauma is… we can’t possibly have them at the forefront of our consciousness at all times or we wouldn’t be able to function. Flashbacks happen, but in some cases it’s possible that with time and effort, each triggering of memory can be quickly dealt with so the memory doesn’t continue to play out and continue causing psychological distress. I’ve had a few memories I’ve had to consciously and repeatedly shoo every time they came up until eventually they almost never came up anymore. In the case of DID, instead of using learned techniques that consciously backseat those memories, a flashback can trigger a dissociative state. It effectively does the same thing and derails the distress, but obviously it’s not healthy.

            I have to admit I have *no* idea what therapy it is you’re referring to. From what I can tell, my mom was taught healthy methods of dealing with memories, ways to identify a dissociative state, ways to identify the ‘alters’ she’d developed, ways to reintegrate the fractured parts of herself, ways to *avoid* a dissociative state, stuff like that. In the course of that, I know her therapist *did* directly engage some of the distinct personalities, but the goal was always to deal with these aspects in such a way that they’d be amenable to *not* asserting themselves anymore.

            After learning how to identify not just the personalities, but the circumstances in which they were most likely to assert themselves. she was also able to learn coping mechanisms that could help avoid a dissociative state in the first place. Those are the reasons she was able to change her behavior.

            I don’t know what other therapists are doing, but I do know that a non-zero number of people who enter therapy and are diagnosed with DID really truly already had the disorder prior to having therapy. That all by itself was the entirety of my point.

            And of course, likewise thank you to you as well. This subject is nothing short of explosive, to be honest. I’ve had a lifetime to wrangle with it (whether I knew it at the time or not) and a lot of my own therapy to develop nice healthy habits of my own. (I do not have DID, by the by.) One of which is to try to talk to people on the internet as if they were sitting in front of me. :)

          • Jax Raven

            No matter how many web sites you link to your comments still makes it BS!. anyone with any REAL first hand experience with DID knows that in cases that are not related to war and combat that it begins from trauma almost always at an extremely young age like 2-5 years of age… when a child ISN’T EVEN SEEING A THERAPIST. it is in fact difficult to get doctors to diagnose properly because most doctors do not know what they are looking at when they see it because they are NOT educated properly. In very very few cases people have been confused in thinking that they have multiple personalities in order not to take blame for their actions. But in the case of a person with true DID it is like a FUGE state where when the host comes out they have no memory of what was occuring while the alter was “out”. and it is not until after lots of practice that the host and alter can learn to be CO CONSCIENCE and share experiences. THIS IS HOW THE ALTERS CAN SHIELD THE HOST FROM THE ABUSE. Seriously people this is not a difficult concept to grasp, and the fact that so many people WITHOUT first hand knowledge speak as if they have a degree in it makes treatment of DID so difficult!

    • Jennifer Nykanen

      Interesting how you seem to think the validity of a condition depends upon your belief. Like it or not, DID is still listed as a very real mental illness.

      • davidkennerly

        Controversially so. No, my belief has nothing to do with it. What matters is what the science tells us and the basis for its inclusion in such tools as the DSM. My perceptions, however, based upon several decades of (admittedly, as a non-psychologist) cultural observation tell me that the origins of DID are very inauspicious, indeed and, more importantly, that there are serious neuro scientists who share my skeptical view.

        • Jax Raven

          hahahahaha, cultural observation. thats like saying your an ornithologist because you’ve seen birds. Unless you have had first had dealings with AN INDIVIDUAL with DID then you know NOTHING and I really mean NOTHING.

      • BridgetBishop

        The DSM was recently rejected by the NIMH for its lack of scientific validity and its cultural bound belief based diagnoses. A bunch of ‘experts’ who make money off the diagnosis heading up working groups for the diagnosis is no way to edit a mental health manual. BUT THE AMA DID EXACTLY THAT!

    • Jeanine Marie Claar

      Because it does

  • PsyoSkeptic

    This is ridiculous unless you ask some people to do this test and try to beat it. If any one person can then you’ve got no reason to believe in some special mechanisms. I’m sure the person defocuses when they are “blind” anyway… not just for this. And I’m also pretty sure we don’t have any evidence whatsoever for what the VEP is when people are trying to pretend they’re blind or not see the items.

    And don’t have someone who is already involved with diagnosing 10 personalities involved in the damn testing. I’m not sure we should believe anything they say anyway.

    • Neuroskeptic

      I agree that if it were possible to “beat” a VEP test then that would make this case much less impressive. Having said that, VEP is used as a means of detecting malingering in people who say they are blind.

      • non_sig

        Whem I’m very tired I find it easy to defocus (and hard to focus). I don’t know if that is normal or not, but in any case, ppl who find it easy to defocus when tired could be tested as a control. At least subjectivly it is possible not to see large objects by defocussing. (Also in experiments, when you are tried and bored by seeing 1000 times the same stimuli.) (No idea, but maybe also ppl good/experts in meditation would be good at that task.)

      • PsyoSkeptic

        You’re right NS but the question is not whether it’s generally useful in detecting malingering but foolproof. Even Gundogan, Sobaci, & Bayer (2007) concludes 94.5% of the time a pattern indicating malingering is accurate. That leaves open lots of opportunities for specific instances of people beating it.(I unfortunately don’t have access to the original article to check what other procedures were used to check for malingering)

    • BridgetBishop

      In order to really test this, you’d have to subject the test subjects to hypnosis and drugs for years to create the conditions DID patients have to endure. It’s more than faking. It’s more in line with brainwashing. Relying on self reports of someone who has been through this therapy for years is bogus…as is, I agree, involving mental health people who diagnosis this stuff. Bennett Braun was one of its top proponents. His ‘research’ is still cited by DID proponents, many of whom he trained.

      • 11223

        Is it possible to be spiritually brain washed and turned brain dead instead of blind?

      • 11223

        Is it possible to be spiritually brain brain washed and have a personality disorder created and manipulated to be brain dead instead of blind?

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  • silverccl

    In view of the bases for DID include extreme physical & sexual abuse at very early ages, (like as toddlers or younger,) this is hardly an enviable diagnosis or condition.

    • BridgetBishop

      I think you mean “basis.” And there is no basis to DID. It’s rehashed Freudian mythology that has resulted in some real harm to people. The diagnosis should have been abandoned long ago.

      • silverccl

        No, I mean BASES, as in more than one basis. There are any number of early childhood experiences which result in fragmenting of personality. There are even some experiences in adulthood, generally young adulthood, which cause such breaks. Must be nice to know everything about everything & dismiss others’ hard work with a single stroke. I imagine it keeps the world nice & tidy.

        • BridgetBishop

          If you read the article from Scientific American I linked you’d see that that claim has claim has no basis in science. “The repression presumably happened because the patients weren’t able to deal with the memory, which has led to their innate coping mechanisms pushing it out of their conscious mind…The problem is that there is no empirical evidence to support such notions, certainly not in the way that Freud originally conceptualized them.” Show me research and I can respond with facts. All the evidence shows traumatic memory works in the opposite way: it CAN’T be forgotten. The more traumatic the memory, the more encoded the information becomes, the more intrusive the memories. Think war veterans which were the basis for the original PTSD diagnosis. They can’t forget their traumatic memories. Show me research, if you have it. I’ve looked and looked. It’s a claim circulated by some therapists (many who diagnosis DID) that has no basis in reality. ‘Extraordinary claims require extraordinary evidence.’

          • jz1993

            You’re being a troll, plain and simple. It’s possible to find many sources which say a whole lot of things about DID. Just because you have a source doesn’t mean it’s correct. If the conversation is annoying you, quit participating.

          • BridgetBishop

            On the contrary, I started off believing in DID very much so. It’s only when I started looking into the decades of evidence, some of which I posted that I concluded what most researchers have: the whole industry is a sham. The conversation is not annoying me at all. I like sharing evidence. That’s how science works. Try it! And have a great day!

          • jz1993

            I have DID from early childhood trauma. It’s a very real thing, and no amount of someone saying otherwise will change reality. I have lived with it for all of my life that I can remember. There are many of us out here who learn how to work with it and live typical lives. I’ve never been hypnotized, so there’s no way I was hypnotized into thinking I have it. Yes, there’s some fraud out there – but that doesn’t mean that DID doesn’t exist. You’re using a very broad brush to paint your argument; a finer tip would give a more accurate result.

          • BridgetBishop

            I am sorry for you childhood. jz. I’m not going to engage a DID diagnosed person. It never goes well. My issue is with the therapists who should have the critical thinking skills to see through this diagnosis. (And the many of them who have caused irreparable damage with their nonsensical treatment models – there is no healthy model.) Have a good day!

          • jz1993

            I’m not buying the “Have a good day”. You imply above that you value discussion, yet that discussion ends when I say I have DID? That’s not terribly open-minded. It’s certainly not a two-way discussion. It’s clear that you’re not here to have an adult debate or even a conversation. Please understand that I fully understand that you are writing what you’re writing because you like to hurt people. I hope you find some help, soon.

    • username

      It’s enviable among a certain community that treats survivors (and “survivors”) as heroes; they suddenly have status and importance and their word trumps all others, on all subjects. “I’m a survivor”, “Don’t question my reality” and other similar phrases are the ultimate conversation-stoppers — not just about abuse, or DID, but on *any* subject in which the person happens to be backing themselves into a corner. There are even people who self-diagnose and essentially train themselves to act and think as if they’re “multiple”. Nor are they faking, exactly; some of them do genuinely believe, or come to believe, their own self-constructed narrative. This self-induced multiplicity is primarily found among impressionable teenagers, but not always. And it happens enough that it can’t be written off as an anomaly. I’m not necessarily suggesting any of this applies to you, personally, but there’s a
      very real incentive in a substantial subset of the population to
      embrace this diagnosis.

  • BridgetBishop

    DID therapy often involves many sessions of hypnosis, which by its very nature, is a self-selecting group of suggestible people…disproportionately women – a trope that has been in place since Freud.

    • ralyto

      I think you are concentrating too hard on your personal disbelief on the whole DID thing (and your skepticism is something I share) to see the very interesting thing this paper actually reports, DID aside.

      To me, this study shows that this patient really does not see when she reports so. If you look at some VEPs obtained under hypnosis or anaesthesia, you’ll see that, although slightly different in shape, the responses are still (very) clearly visible. Also, 13 years before the whole psychotherapy thing, when she had her head trauma and got examined by opthalmic specialists, after multiple tests they diagnosed her as cortically blind.

      I share your view on multiple personalities being a culturally contructed craze, and my hunch is that psychatrists have done more harm than good on this, but the truth remains that many patients do believe in their personalities and act accordingly.

      I find it quite remarkable to see that a delusion could go so far as to completely inhibit the basic sensory experience which is vision!

      • BridgetBishop

        You are free to think as you wish.

        You are assuming the test was unbiasedly administered and interpreted by advocates of DID to support DID? That’s a pretty big assumption. I’ve looked at the “studies” of these two people…like most therapists whose work is shunned by scientific journals, there is no real research among their “papers.” They resort to theory and unrepeatable “case studies.” You have to rely on faith to think they did this objectively as nobody can seem to access the (case) study.

        Here is the a similar trope about eyes being bantered by their colleagues before he lost his license (Bruan). It turned out to be complete BS. Like this journalist, the journalist here accepted it on face value. It’s a shame people who cover science don’t know how to evaluate “studies.”

        Check this out from the NYT: “Similar differences were found in other patients. ‘One patient had had his left eye injured in a fight, so that it turned out,” said Dr. Miller. ‘But the condition only appeared in one of his personalities. It disappeared in the others, nor was there any evidence of muscle imbalance.’

        The study corroborates an observation of vision differences that had often been made by those treating multiple-personality cases. ‘Many patients have told me they have a drawer full of eyeglasses at home, and they never are quite sure which to bring when they go out,” Dr. Braun said.'”

        A Dallas paper was a little more skeptical when this DID Doctor a colleague of the above made crazy eye claims (Colin Ross
        I don’t know what the fascination is with eyes with these folks.) This is hilarious. Colin Ross’s “tests” are still used to diagnose MPD/DID. He is considered a pioneering researcher of MPD/DID, which speaks volumes about DID standards of research. SHOW US THE STUDY!

  • sonia

    It would be interesting to observe what triggered the switch. Was it a word that changed her DID state? How did they trigger her blind state? I’m surprised they didn’t test her visual function when blurred and in a seeing state. That may rule out the possibility of statistical flukes from potential priming prior. If she was “pretending ” to be blind she could’ve read a lot about how blind people see. Did she roll her eyes backwards? Cross her eyes? If I was pretending to be blind I’d naturally cross my eyes or blur something. How was her gait, speech and coordination when blind? I think it’s more than just being visually blind, but other senses more heightened, ability to read braille faster, these should be tested too. Being blind isn’t just limited to vision.

  • sonia

    If she was blind at 33 she should be able to read braille. Did they test her braille reading ability or assess for blind scores like visual hemiplegia, shine a light in her pupil? something doesn’t add up.

    • Laren Ganer

      The way you put this makes it sound like the ability to read braille is something you automatically gain upon losing your sight, instead of a skill anyone at all can learn at any time.

      • sonia

        No, that wasn’t my point. No person with a visual deficit is without struggle. She would’ve been taught braille since a young age so she can read. If she’s genuinely blind she should read braille. I see her behavior no different to someone parking in a disability spot for their psychotic convenience.

      • sonia

        Further to that. Her brain pattern just like when someone reads visually would conform to an experienced braille reader. I don’t believe for one sec the observations reported in this paper are valid.

  • Anechidna

    I have had experience where one individual would lose vision for limited periods of time. They were totally oblivious to stimuli when this occurred. The individual was aged 10 and the driver for this behaviour was found to be the medication prescribed by a Paediatrician, it was determined in the hospital by other Paediatricians that the child was being overdosed and this was the physiological response.

    Of more interest in this case, was the patient suffering from a Dissociative Identity Disorder or was it a Multiple Personality Disorder, there is a significant difference between them but often the DID is mistaken for MPD. In the former it is very possible that the individual when they dissociate to an Identity may actually not be able to see simply because the DID disorder is a survival mechanism for horrific physical, emotional abuse akin to torture. But if they were dissaociating then there would also be the presentation of that personality being represented at that time, there would most likely be a voice change with respect to tone, clarity (dialect/accent) and it would be very obvious you were relating to another personality. The DID personality’s are merged back into the core identity as the events that cause this dissociation are dealt with via therapy.

    So the question has to be asked was the individual concerned receiving therapy which would then resolve the personality separation. The switching between identities is rapid but generally you only get one identity and then the core identity until you have dealt with the events that trigger that identity and then you move to the next event and the next identity.

    So while I am not convinced there is enough to suggest a possibility that the case study is correct. Were they subject to sexual abuse, torture as a child/teenager/young adult this is pertinent to whether it is a DID or a MPD presentation.

    • Laren Ganer

      DID and MPD are not two different diagnoses; the term MPD has been deprecated in favor of DID. Usage of the term “multiple personality disorder” is obsolete, but when it is used, it refers to dissociative identity disorder.

      • BridgetBishop

        Yes, that’s because MPD therapy was leading to too many pesky lawsuits so the ISSMPD (International Society for the Study of Multiple Personality Disorder) started by Bennett Braun who lost his license over his techniques got it renamed in the DSM to DID and called itself ISSTD (International Society for the Study of Trauma and Dissociation and Dissociation). It’s called “rebranding.”

      • Anechidna

        From what I have seen those who have experienced severe Trauma whether through abuse as children or older survive those incidents via the creation of the different Identities. Yes they can often then express that experience via what can be termed self destructive behaviours some of which are to form unsafe relationships or even if safe they have great difficulty in maintaining them due to the underlying and untreated trauma.

        The whole process of trying to collapse all into a single diagnosis is unsafe as it makes an unstated generalization that a trauma induced Identity Disorder is a Border Line Personality Disorder. I have observed the results of such presumption and all I can say is that it is a highly dangerous approach demonstrating little comprehension (although full understanding is claimed) of the differences between the disorders.

        The approach is akin to Physicists claiming that a single equation can explain everything. Eventually it may but until you can accommodate and account for all the elements to be included no progress will be made. In the meantime those experiencing DID’s induced by trauma suffer further abuse from those supposedly supplying assistance to resolve those experiences. Is a DID torture victim the same as a BLD sufferer, from my experience they are poles apart and to say they are demonstrates the lack of capacity within the Health Sector to adequately address all needs.

  • Mary Vanrynsoever

    I worked for a person that had multiple personality disorder and she harmed a lot of people including her daughters.she was evil. finely I quit but the damage she has done is awefull

  • Laren Ganer

    That’s pretty wild. Due to necessity, I’ve been doing research into practical methods of, to put it simply, ‘retrain the brain’ to more easily return to a state of relaxed awareness (as opposed to being in a state of fear response). The road there has been rocky and sometimes I really do start to doubt the extent to which our brains can really be that plastic.

    If this is not a case of fraud, it may be evidence that our brains have the capability to be nothing short of acrobatic, given the right training or stimulus.

    Which I guess is some bizarre bit of hope for me.

    I wonder if B.T. is working in therapy to attempt to regain her sight. If this is not a conscious fraud on her part, it must be an incredibly frustrating situation. She knows she can see sometimes, but can’t necessarily control when, and there’s no obvious way to attempt to ensure she will someday be able to consistently see.

    As controversial as DID is, those who have it (and not due to iatrogenesis) are, during the course of day to day life, genuinely unable to completely (if at all) control their episodes of disassociation and/or manifestation of an ‘alter’. Some are able to learn methods of coping with unexpected triggers that help them prevent dissociation, but unless that person is superhuman, at some point they’re going to have a bad day. Being too tired, being overwhelmed by stimuli, having an illness of some sort, all of that can interfere with full usage of coping mechanisms.

    This would mean B.T. wouldn’t be able to control when she had sight. That would be just miserable.

    Even more interesting, generally the goal of therapy for DID is to ‘integrate’ the fractured personalities into the patient’s core personality. Since B.T. has been blind for years, it’s safe to assume her ‘core’ personality is blind. Would a successful integration of whichever personalit(ies/y) are sighted result in her becoming sighted all the time… or blind all the time?

    In any case, this is at least pretty darn interesting.

    • jz1993

      I have DID plus am recovering from brain lesions and nervous system damage from a genetic metabolic disorder. Keep exercising your brain; it’s amazing what you can get back. Don’t listen to those who say things can’t be done – as one of my alters says, always do the impossible before you know it’s impossible – once you know it’s impossible, it will be. Before that, the sky’s the limit. And yes, there are bad days with DID – but many people with DID learn to handle them. Best of luck in your mental acrobatics :)

  • Richard H Barker

    Info gathered from our senses is combined with info gathered
    from culture and woven into a coherent narrative, our Story about the world and our place in it (i.e. the DMN). All info within the Story is considered to be true; thus any fresh info that is contradictory is considered to be untrue, or more to the point, considered to be a threat. The Story has many tools to prevent threatening info from invading (it can borrow the Fight Or Flight Response, subconscious lie detection, etc.) but the most powerful of all is that it decides what tiny percentage of sensory input it will allow to enter awareness.

    The one thing we know about patient BT with absolute
    certainty is that her Story is going to extraordinary lengths to protect her
    from threatening info, including 10 (!) different avatars (egos). In the
    healthiest of humans, less than 1% of all sensory input is allowed to enter
    awareness, so it should come as no surprise to come across a Story that has gone just slightly further and blocked 100% rather than just 99%.

    If indeed her Story is to blame for her blindness, then we would predict that revealing the machinations of her Story to her Psyche—the whole
    point of therapy—would hobble her Story enough to allow her Psyche to regain some control, including vision, and she does seem to be moving in that direction.

  • abigal241

    DID Dissociative Identity Disorder (previously called MPD) has been proven to be caused by severe repeated trauma. See

    • Anechidna

      They don’t get it (comments). Definitely not a mental illness. A survival mechanism handled entirely by the brain dealing with severe emotional trauma.

      • jz1993

        As someone with DID from severe childhood trauma, I can verify that it does exist. I reject the notion that it’s a mental illness or dissociative “disorder”; a disorder means something that goes against order. DID doesn’t. What many “experts” totally overlook is that DID is only dysfunctional *outside* the environment that caused it. In the environment which caused it, DID confers a survival advantage. Mental illnesses don’t. Schizophrenia doesn’t help a person survive; neither do bipolar disorder or major depressive disorder, etc. IMO, DID needs to be classified and viewed as a dissociative *adaptation*, because that’s what it is. Conditions in my early life were unlivable. DID gave me the ability to diffuse the abuse to many personalities so that no one personality had to take it all. Because I have DID, I could compartmentalize the trauma until I such time as I was in a safe enough environment to deal with all of it. Because I could compartmentalize the pain, I was able to function normally on the surface. I have always passed for normal; I have two college degrees. I have a job that I love. DID is, to me, a normal part of life. I haven’t ever experienced anything on the level of blindness between personalities (I, too, can switch between personalities within seconds; it’s something which I’ve been able to control for a long time), but I have experienced one or some alters having a headache, anxiety-related stomach ache, etc. while others don’t. I used to switch eye dominance between some alters. As I became more integrated, switching eye dominance caused horrific headaches, so we all worked on being right-eye dominant & became so. I can still switch eye dominance at will, but I don’t due to the aforementioned headaches (although I’m great at shooting pool and playing darts while left-eye dominant and right hand-dominant. Why? I have no clue, it’s just how my brain works). Research on DID has shown that different alters use different parts of the brain or use the brain in different ways. This, to me, makes sense of some alters having sight in the article example and some not – some alters are using the brain in such a way that sight isn’t being accessed. Personally, I’m better at writing than my other alters, while other alters are better at editing than I am (I write and edit a lot for work, so we function together as a team). I have alters that are better at math, alters who are better at learning languages, and alters who are great at drawing. So even though we all share the same brain, we’re accessing different areas in different ways. The stigma against DID is a major obstacle to healing because it causes so much isolation. The only way for alters to heal is to let them have experiences in safe environments – but due to stigma, alters have to hide behind the host alter (the main persona/the alter who is in charge of interacting with the outside world). It’s hard to heal when no one can know you exist. A more understanding and accepting society would help people with DID heal a hell of a lot faster. I look forward to a time when people who have DID are respected for their strength and fortitude instead of being rejected and ridiculed.

    • BridgetBishop

      No. That’s not proof. That’s from an advocacy group. Many of those studies and researchers have been entirely debunked. They are all by advocates of DID and not published in scientific Journals. For Example Surachi published a vanity book that’s been panned. If you are going to use Wikis, may I suggest Wikipedia, which is much more balanced? “DID is one of the most controversial psychiatric disorders, with no clear consensus on diagnostic criteria or treatment.[3] Research on treatment efficacy has been concerned primarily with clinical approaches and case studies.” Exactly!

      • Lew Powell

        Wikipedia has had to prohibit “satanic ritual abuse” and MPD/DID believers from editing entries on those subjects, just as it did Holocaust revisionists….

    • Lew Powell

      I hope readers followed your suggested link. Here’s the kind of baloney they would find:

      “Two early personal accounts written about MPD in book form were The 3 Faces of Eve [17] about Chris Sizemore and Sybil: The Classic True Story of a Woman Possessed by Sixteen Personalities [18] about Shirley Mason. These books helped validate the existence of MPD as a legitimate disorder….”

    • Abigail241x

      The articles in the childabusewiki use citations from peer reviewed scientific journals.

      Wikipedia is not accurate. It is well known that it is an open source that can be edited by anyone. A person does not need to have any credentials to edit Wikipedia. It is not fact checked and has been found to be less accurate than real encyclopedias. Wikipedia articles on child abuse and dissociation are heavily balanced toward the denial of child abuse and are controlled by “skeptics.” The DID diagnosis is attacked because of its traumagenic origins. In other words, those that deny DID’s proven traumatic origins are often connected to those covering up child abuse.

      Since someone mentioned the ritual abuse article, here is an accurate one that balances theirs.

  • Julian Sammy

    In Medically unexplained visual loss in adult patients (Eye (2004) 18, 917–922. doi:10.1038/sj.eye.6701367) by P G Griffiths and D Eddyshaw, they note that “the use of pattern evoked potential (P-VEP) in the diagnosis of nonorganic visual loss is controversial as many subjects can alter or extinguish their P-VEP.” They cite these papers:

    21. Morgan R, Nugent B, Harrison J, O’Connor P. Voluntay alteration of pattern visual evoked responses. Ophthalmology 1985; 92: 1356–1363.

    22. Bumgartner J, Epstein C. Voluntaty alteration of visual evoked potentials. Ann Neurol 1982; 12: 475–478.

    Perhaps a more skeptical methodology that controls for intentional and unintentional VEP alterations would give more confidence in the conclusions.

  • Pingback: 她視力時瞎時恢復,並不是因為眼睛受傷,而是因為她身上的10多個人格,並非全部都是瞎子?! – read 123 閱讀網()

  • Jax Raven

    I Live and am a caregiver for someone with Severe DID. Anyone who thinks that this condition just DOES NOT exist in short has really had NO EXPERIENCE WITH IT. Its like giving your professional opinion on the stock market when you can’t even count your own countrys currency. Yes there are “fakers”. That does not mean that it doesn’t exist. there are people that fake CANCER, but making each patient prove their diagnosis to a narrow-minded skeptic by DYING from it is ridiculous. The brain Creates paths to map out our personalities, new ones forge new trails in the brain, like map upon map. Vision is ONLY achieved if the Vision centers of the brain are activated. There may have been some REAL reason that these alters are not allowed to access the vision centers of the brain. most likely to PROTECT the host or alter from seeing the trauma that was happening. Why you can’t see the simplest reason that the brain would shut off the vision is beyond me. But DID is a result of trauma or abuse, and the BRAIN TRYING TO PROTECT ITSELF FROM THE TRAUMA. ANY part of the brain can be shut off or lost, that is what happens during stroke. The fact that you think that the Brain can not chose to do it out of SELF PRESERVATION shows how little you know about DID itself and about nature. The fact that some of her sight is coming back could mean that her therapy may be helping her brain to let down some of its defenses. instead of looking at this like some woman is trying to pull the wool over your eyes by ruining her life and living as a blind woman for no reason at all. how about thinking about it a little and realizing that maybe she was made to see something so horrendous that her mind decided that she needed to SHUT HER EYES OFF to save her life, and how sad that must be!



No brain. No gain.

About Neuroskeptic

Neuroskeptic is a British neuroscientist who takes a skeptical look at his own field, and beyond. His blog offers a look at the latest developments in neuroscience, psychiatry and psychology through a critical lens.


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