I don’t know about you, but my life has had more than a few strange moments. It is always hard to know what to say when a close friend “comes out”. There was the time when I got into trouble during a night dive on the reef. I’ll never forget meeting my complex and unusual mother-in-law for the first time at our wedding (and neither will our guests, no doubt). An aesthetically weird experience was listening to grotesquely distorted radio transmissions while touring the barren moonscape of low hills and salt flats surrounding Lake Eyre south, alone. After a while it seemed as though whispered words in a demonic voice could be discerned within the metallic noise. Working at a truck-stop in the middle of nowhere in the middle of 45 degree heat was quite an experience. There really are people in this world who enjoy a king-sized lime-flavoured milkshake. I’ve been many things and done a lot of places, or is that been many people and seen a lot of places? I’m not sure, but I’ve been around. In addition to the strange and challenging situations that any person who has lived a reasonably rounded life encounters, I also have odd experiences of a neurological nature. With the wisdom that only comes with maturity, I understand that nature has been kind to me, because she has done so much to make my life interesting.
The Strange Phenomenon
John* is a man who’s face I see at least once a week. John is a bit of a character, but I’ve got a lot of respect for John. John is not my friend or anything closer than that. John has an interesting face, and it attracts my attention when he is speaking. His face seems unusual in that it looks quite different when viewed from directly in front compared to how it looks viewed in profile. John has a facial feature that looks prominent in profile but looks like nothing much at all from a full-face view. This is almost like an optical illusion, and it gives John’s face quite a different “personality” when viewed from different angles. Visual curiosities like this grab my attention.
I’m not sure when it was that I first noticed “the strange phenomenon”. It has happened repeatedly over many months at least, possibly over a year. I know for sure that it was happening during the first half of 2010. While watching John (speaking or not speaking), if I was paying attention and also viewing his face from a position at around 45 degrees to the side (the only viewpoint that can capture the overall character of John’s face), and his face is also lit by natural sunlight, then, automatically and without warning, a very vivid memory of the face of Jean*, as she appeared years ago when I last saw her, viewed from exactly the same angle, would appear in my mind’s eye, sort of super-imposed over my real-time visual perception of John’s face. Once my memory of Jean and her face is “unlocked” in this way, memories come to mind about how she looked, and sometimes I recall the sound of her voice, which seems similar to John’s voice, in tone and also in emotional expression, even though there is the obvious gender difference. Maybe Jean is a bit less feminine than the average woman, but generally John and Jean seem pretty normal in terms of gender characteristics. I have never thought of them as androgynous. They both are intelligent adults and there is nothing blatantly strange in their manner or appearance. I have two theories about why this phenomenon is strongest at a 45 degree angle – this angle gives the best overview of a face, and also this view minimizes at least one gender difference between male and female faces. Men generally have broader faces than women, but this facial sexual dimorphism is minimized when viewed from the side.
I have never had this type of experience involving the faces of any other people – it only happens when I’m looking at John’s face. What’s so special about these people that they are the only faces that provoke this strange phenomenon? I will offer an explanation later. The short answer is that their faces look incredibly alike. As I remember her, Jean wore little of no makeup. I suspect that her resemblance to John might not have been as noticeable to me if she had worn enough makeup to make a difference to her facial appearance. It has been a number of years since I last saw Jean, so I don’t know if this strange phenomenon might work in reverse – with Jean’s face automatically evoking a visual memory of John’s. Jean’s face was the first of John and Jean’s faces that I ever saw. There is no overlap in time of the different periods of time when I’ve seen their faces regularly. At least five years separates these periods.
Who is Jean? Jean is a woman who served me over a counter, sometimes, at a place that I frequented for a few years about seven years ago. I haven’t (knowingly) seen her for years. I did not know her socially and I wouldn’t say we were particularly friendly (or unfriendly). At the time there was something in her manner and presentation that gave me the impression that there could be an unusual conservatism in her personality. I hardly remember Jean, except for those times when I see her face and hear her voice with stunning clarity in my memory. (Does that make sense?) I had not thought of Jean being in any way connected to John or resembling John before the strange phenomenon started happening. I just hadn’t seen the connection before. I have no record of Jean’s appearance besides my memory, and I don’t think I ever knew her surname. Jean and John would be roughly similar in age, but they are not siblings. I am not aware of any familial connection between them, but I also can’t be absolutely sure that none exists.
The strange phenomenon is a very orderly, sensitive and predictable thing. Conditions have to be “just right” for it to happen. If John’s face is not lit by sunlight, the phenomenon will not happen. If John has a big, beaming smile, it will not happen, but a more subtle smile sometimes does not block the phenomenon. If John looks inebriated or unusually emotional in some way, the phenomenon does not happen. When John gained weight, the phenomenon stopped. Excess weight distorts and covers some elements of the appearance of the face (and is also a health hazard). The strange phenomenon does not happen if I view John’s face from a profile view, and it rarely happens when his face is viewed from a full-face angle – it generally needs to be viewed from 45 degrees. The strange phenomenon requires viewing of John’s face in the right conditions for a few moments before it happens – it happens abruptly but not instantly.
Since I was a young child I have had synesthesia/synaesthesia. Synaesthesia is a common benign condition of the brain associated with an unusually rich network of connections in the white matter of the brain. Most cases are genetic in origin, and it runs in my family. One of the types of synaesthesia that I have, coloured letters and numbers, is associated with “extra activations in the fusiform gyrus” which is a part of the brain. The fusiform face area is the part of the brain that “does” face recognition. It is situated within the fusiform gyrus. It appears that there is something interesting going on in my fusiform gyrus. The strange phenomenon has many features in common with synaesthesia, and I believe it is an unusual type of synaesthesia. I believe the very specific image of John’s face seen under very specific conditions is an inducer, trigger or stimulus of my synaesthesia, and my remembered image of Jean’s face is the concurrent or additional sensory experience in my synaesthesia. Like synaesthesia, the strange phenomenon is automatic. It is not something that I “do” intentionally or wish to happen, although I find it amusing to anticipate it and then see it happen. I am sure I would be unable to prevent it by conscious will from happening. Like synaesthesia, the phenomenon is reliable. Given exactly the right conditions, it will happen.
What does the strange phenomenon feel like? The normal process that this phenomenon most feels like is face recognition, but with the twist that my mind “changes its mind” about who it is looking at. It feels as though at first my mind normally recognizes the face as John’s, with no fuss, but then it seems to impose a different interpretation, dredging up Jean as a better answer to the question of “Who is the owner of this face?” I’ve wondered why my mind should be so willing to abnormally review its original correct decision. I can only guess that there is some mechanism in the brain that gives precedence to much older face memories when choosing between very similar-looking stored memories of faces during the process of identifying a currently seen face. Alternately, my brain, and all brains, might be designed to identify not only the faces of individuals, but also to identify similarities betweenpeople’s faces, as a clue to genetic relatedness. I know enough about biology and evolution to know that intelligent animals such as humans are likely to have evolved features to help us to identify our kin and kinship between others.
Does the strange phenomenon cause emotional distress? Not to me, but it is a weird experience. Many of the types of synaesthesia that I experience are so unobtrusive and fleeting that they can go unnoted, and some types are so predictable that they feel completely ordinary. In my experience it is the types of synaesthesia that are rarely experienced and are person-triggered that are the most startling and subjectively weird. The strange phenomenon fits into both categories. It is these experiences that can make one think “WTF?” or “S*** a brick!” or “That is the strangest thing!” (to quote the title of a book about synaesthesia).
Viewing people’s faces is obviously a social-type experience. As anyone would, I feel as though I am witnessing moods and personalities when I view faces. I wouldn’t be surprised if John and Jean turned out to have similar personalities, but at the same time, I don’t feel that I can read Jean or John “like a book”.
When John gained weight the appearance of his face changed and the strange phenomenon stopped. This is not the first time that a type of synaesthesia that I’ve experienced that is triggered by particular characteristics of a person has been extinguished by a change in that person. This possibly gives me a greater appreciation of time and people, and the brevity of childhood and life in general.
There are many reasons why I believe that this strange phenomenon is interesting and unusual. It seems to be a mixture of synaesthesia, ordinary remembering and face recognition, and I’m sure this is an unusual thing. The strange phenomenon differs from ordinary remembering in many ways. It requires a very specific visual trigger, it happens repeatedly and reliably, like synaesthesia it relies on attention but is otherwise independent of conscious control, and it evokes a vivid memory of the face of a person who shouldn’t be memorable to me. This phenomenon is one of two different types of synaesthesia that I experience which automatically “unlock” vivid and often very old visual memories, giving extraordinary glimpses into a world of visual memories that are apparently stored away in my mind like photos or videotapes, but can only rarely be accessed.
Significantly, the other type of synaesthesia of mine which gives spontaneous vivid mental images evokes my memories of specific places (not people) that I have visited in the past, but which often aren’t particularly memorable. These “visions” of places look as they did last time I saw them, frozen in time. I “see” places (in my mind’s eye) that have since been demolished, and some of these images date back to scenes my early childhood. These involuntarily recalled visual memories of places are only visual experiences, they do not involve smells or sounds or other non-visual types of sensory experience. There appears to be a neurological link between the recognition of faces and the recognition of places, with disability in recognizing both of these types of things found together in some people. The famous neurologist and author Dr Oliver Sacks is one person who has prosopagnosia (a disability in recognizing faces) and also a disability in recognizing places. There appear to be two different scientific terms in use for this neurologically-based inability to recognize scenes: “agnosia for scenes” (seen in a New Scientist article) and “topographical agnosia” (Sacks 2010). In a recent article published in New Yorker magazine, and also in his recent book The Mind’s Eye, Dr Sacks described his problems with getting lost in the streets after unknowingly walking past his own house a number of times, and also being unable to recognize people he knows well. The British primatologist Dame Jane Goodall is another famous person who has trouble recognizing faces and also places. Faces and places are the only types of things that I receive spontaneous “visions” of. I am sure this is no mere coincidence. Like the strange phenomenon, I find it amusing to anticipate receiving a “vision” of a place when the conditions are just right, and then watching it appear, suddenly, and for no logical reason.
My strange phenomenon has two features which I believe make the strange phenomenon truly strange: it involves effortless mental processing of a task that should be rather difficult (sorting through a lifetime of memories of countless faces, then matching two faces of people of different genders that look very similar from angles which give a view that is least affected by sexual dimorphism), and the strange phenomenon also manifests as a very vivid image in the mind’s eye (language and words have no role in this phenomenon).
I have grapheme-colour synaesthesia and I am closely related to people who also have this type of synaesthesia and who have also been formally offered places, more than once, to gifted and talented educational programs. I believe there is a connection between the synaesthesia and the smarts. I am also in a family that has at least four generations of people who have particular talents in the areas of English and foreign languages (grapheme-colour synaesthetes are among this group). I believe it is possible that which ever genes give rise to grapheme-colour synaesthesia and related cognitive differences could be evolutionary adaptations that give an advantage in learning languages and reading. I believe it could be as simple as a gene that boosts the development of visual memory, for words, letters and also faces.
I am not aware of any description in the scientific or popular literature of an experience that is genuinely the same type of thing as the strange phenomenon. This does not make me doubt the reality of what I have experienced. I would expect that this would be a rare phenomenon, because it is the result of a combination of some most unusual factors – two different observations of a quietly unusual pair of people, separated by a very long period of time, observed by another unusual person, who has the interest in scientific matters and the inclination to try to make sense of it all. Rare things do happen, but not very often.
*Not their real names. Obviously, the true identities of John and Jean cannot be divulged.
Alternative ways of categorizing the strange phenomenon/competing explanations
Is it just an idiosyncratic and meaningless connection between two things due to synaesthesia?
I don’t think so. The two people objectively do look similar, so the link does not seem to be random or accidental. It’s not as though the sight of a face make me hear a sound or see a colour, the strange phenomenon only involves faces.
Is the phenomenon just the simple remembering of a similar-looking face?
No, it is different, because it is much less influenced by conscious control than simple remembering, and the memories evoked are more vivid and extensive than can be retrieved by conscious effort at remembering. Perhaps one could describe the strange phenomenon as face recognition that is “turbocharged” with synaesthesia. The strange phenomenon feels strange, because it makes me see a similarity between two faces and two people that doesn’t seem to make sense – they can’t be identical twins, because one is male and one female.
Is the phenomenon an experience typical of those of “super-recognizers”?
No, but there are many similarities. Super-recognizers report being able to recognize people who were last met many years ago and were not more than a fleeting acquaintance. My remembering Jean is like this. Super-recognizers also are able to recognize despite changes in appearance such as child to adult transition and changes of hairstyle. My recognizing of similarities in faces of different genders is similar to this. The phenomenon feels like face recognition. I have already completed some tests of face recognition ability that are readily accessible through the internet, and I got perfect scores, which could indicate that I’m a super-recognizer.
Is the phenomenon like one of those uncanny moments of noticing a family resemblance, like noticing a grandparent’s frown in a young child?
It is similar to this in that it involves similar-looking people but it also transcends stuff like gender and age, but noticing family resemblances is different in that it is unpredictable, occasional, is typically triggered by gestures or expressions, and does not typically unlock a cache of hidden memories. The strange phenomenon seems to involve the whole face, not a part of the face.
Is this phenomenon a case of mistaken identity with two very similar-looking people, in an unusual situation? (as might happen when meeting the identical twin of a person that one already knows)
This explanation seems applicable in some ways but isn’t. John and Jean do look similar, when viewed from a certain angle, but there is no mistaken identity. All the way through the strange phenomenon my conscious mind is clear about who is who, the identity confusion happens on a more primitive level. I’ve known two sets of identical twins in my past. I never liked any of them enough to care which was which.
Is the phenomenon like recognizing a previously known genetic syndrome in a number of different people, such as identifying that a stranger has Down syndrome?
The phenomenon is similar to this in that it transcends stuff like age and gender. Identifying a person as having Down syndrome is different in that (for me) it is not a strange experience and does not evoke visual memories of individuals seen in the past. I believe my brain treats Down syndrome in a similar way that it treats racial differences. Perhaps my brain would act more oddly when confronted with people who have a genetic syndrome that is not fairly common, familiar and obvious. I think it is likely that John and Jean have the same rare genetic syndrome, but I don’t know what it might be. There is more to this story than I’ve set out here.
Is the phenomenon Synaesthesia?
I believe it is. It is reliable, repetitive, automatic and involuntary like synaesthesia. I cannot voluntarily access my memories of Jean as fully as happens in the phenomenon. It does not require or involve effort. Like synaesthesia it requires paying attention to the trigger. It is sensory (visual). It involves a very specific trigger evoking a very specific experience, like synaesthesia. It happens suddenly and without warning. It “hits you”. Some types of synaesthesia are like this. It involves memory, and synesthetes are thought to have superior memory.
Why do you ask and answer your own questions?
I’m not sure, but it works for me.
Some explanations that I believe are NOT applicable
Some type of delusional misidentification syndrome (DMS)
There are many different recognized types of delusional syndromes that involve incorrect identification of people, and some are thought to be due to faulty face recognition or perception. I have carefully considered all of the DMS’s listed at the Wikipedia, and none of them describe the same situation as the strange phenomenon. The only type of DMS that I have heard of that is in any way similar to it is something that Dr Oliver Sacks described in his article in New Yorker, a hyperfamiliarity for faces that Sacks claims was described by Devinsky (Sacks gives no reference in this article). Sacks describes a disorder in which everyone feels familiar to a person with the disorder, and the person with the delusion might approach strangers and address them as though they are old friends. I do not do this. Even if I was a more extroverted person, I would not do this because I do not have a feeling of familiarity for masses of other people. I believe there is nothing wrong with my ability to tell the difference between faces that I have never seen, and those that I have seen in the past. I can’t imagine what it would be like to walk into a room of people and feel like I was surrounded by old friends. That doesn’t sound like me at all! I’ve had a read of the 2002-2003 journal paper by Vuilleumier et al about a case of hyperfamiliarity for unknown faces. I do not believe I have anything in common with the patient described, except that we both have good face recognition abilities (the title of the paper appears to be a typo). Neither John nor Jean were unfamiliar to me during the time when the strange phenomenon started. Their faces were and are not unfamiliar faces.
The simple fact that I was able to get some perfect scores in scientifically credible tests of face recognition surely shows that I do not have a fault in my face recognition brain “hardware”. I wouldn’t expect a delusional syndrome to be associated with a very high level of ability.
Out of curiousity I did a face memory test that I found at the website of the BBC. I do not know anything about who created this test, but it can be found here: http://www.bbc.co.uk/science/humanbody/sleep/tmt/ I got a perfect score for face recognition, a score of 91% for temporal memory associated with face memory (average score 68%) and a low number of false-positive identifications. I think the fact that I scored very low (one, caused by a misunderstanding of the question) for false-positive identifications shows that my identification of faces in general isn’t influenced by some hyperfamiliarity, misidentification or delusion disorder. I don’t have a general problem with seeing unfamiliar faces as familiar.
There is one area of cognition in which I do possibly have an abnormal sensation of false familiarity. You could call it “dialogue déjà vu”. It is associated with things that I write or say to other people. I might write a note or tell a story to someone else, and immediately after I might feel that it is too familiar, and I wonder whether I have already told that person in the past. The result is that I never feel completely confident about judging if I’ve already had a conversation or informed someone about something, and I annoy family sometimes by telling the same story twice.
A visual disturbance or vision defect
There are some interesting and exotic types of visual disturbances, but they do not adequately explain the strange phenomenon, because it only happens when I see the face of one particular person under very specific conditions. No visual disturbance or defect in vision could be this selective. I have had glasses for short-sightedness since I was a teen, but I only really need to wear them for driving at night. Small print is getting harder to read as I age, and my colour vision at night isn’t perfect, but I regard my vision as pretty normal for my age. As a synaesthete who experiences visual manifestations of synaesthesia as appearing in my mind’s eye, and not projected into space around me, I am well aware of the difference between things seen through my eyes and things seen within, in my mind, memory or imagination. Jean’s face is seen in my mind’s eye – her face is not a defective image originating from my eye.
How blind could I be if I am able to get perfect scores on tests of face recognition ability?
Hallucination
Here are definitions of “hallucination” from three different sources:
Famous neurologist, author and prosopagnosic Oliver Sacks quoted from his Feb 2009 TED talk about hallucinations:
“They don’t seem to be of our creation. They don’t seem to be under our control. They seem to be from the outside, and [seem] to mimic perception.”
Clinical Senior Lecturer and Honorary Consultant Psychiatrist Dominic Ffytche in a 2004 clinical guide to visual hallucination and illusion disorders, on the difference between visual images and hallucinations:
“Visual images appear in the mind’s eye and are under some degree of volitional control, as opposed to hallucinations and illusions which are externally located, unpredictable and outside volition (in the sense that one cannot choose to make a hallucination of, say, a face turn into that of a chair).”
Wikipedia article titled “Hallucination”
“A hallucination, in the broadest sense of the word, is a perception in the absence of a stimulus. In a stricter sense, hallucinations are defined as perceptions in a conscious and awake state in the absence of external stimuli which have qualities of real perception, in that they are vivid, substantial, and located in external objective space.”
The Strange Phenomenon does not fall under the definition of hallucination for two reasons – because it is not percieved or located externally, it is in the mind’s eye, and it does not happen in the absence of a stimulus, the stimulus is the visual perception of John’s face as seen under very specific conditions. This is not a conventional stimulus, it is a synaesthesia-type stimulus.
Psychosis
I do not know what psychosis or insanity are like, as I’ve been fortunate enough throughout my life to never have had such experiences, but I’m sure that such disorders of the mind would not manifest with the great precision, order and rarity of the strange phenomenon. I do not live a disordered life. I have no demerit points on my driver’s licence.
Apparently “It is well established that schizophrenia is associated with difficulties recognising facial expressions of emotion.” (abstract of Tomlinson et al 2006). I have done a test of identifying facial expressions of emotion, the Reading the Mind in the Eyes Test, and I got a score of 33 out of 36, which indicates that I am “…very accurate at decoding a person’s facial expressions around their eyes.” So I guess that means it is highly unlikely that I have schizoprenia.
Recreational drug effects
The same comments apply as those for psychosis. I do not regularly take any prescription, alternative medicine or illicit drugs, except caffeine and the odd aspirin. I rarely drink alcohol. I do not get any effect like the strange phenomenon from any drug or alcohol. Synaesthetes don’t need drugs!
Epilepsy (including reflex epilepsy)
I do not have this diagnosis. There is no shaking or loss of consciousness associated with the strange phenomenon.
Migraine Aura
Headaches are not associated with the strange phenomenon. I sometimes get super-acute senses with a headache, but nothing associated with “visions”, visual disturbance or face recognition.
Illness, fever, sleep deprivation, fatigue, delirium
Not applicable. The strange phenomenon has been happening over a very long period of time.
Religious or supernatural “vision”
I’ve been an atheist rationalist for most of my life. This type of thing doesn’t happen to me. God doesn’t care about me, and the feeling is mutual.
References and recommended reading
Ffytche, DominicVisual Hallucination and Illusion Disorders: A Clinical Guide.ACNR. VOLUME 4 NUMBER 2 MAY/JUNE 2004. p. 16-18.http://www.acnr.co.uk/pdfs/volume4issue2/v4i2reviewart3.pdf
Jäncke L, Beeli G, Eulig C, Hänggi J. The neuroanatomy of grapheme-color synesthesia.Eur J Neuroscience. 2009 Mar;29(6):1287-93. http://www.ncbi.nlm.nih.gov/pubmed/19302164
Lambert, Craig Facial pheenoms. Harvard Magazine. September-October 2009. http://harvardmagazine.com/2009/09/facial-pheenoms
Mendez, MF, Cherrier, MM Agnosia for scenes in topographagnosia. Neuropsychologia.2003;41(10):1387-95. http://www.ncbi.nlm.nih.gov/pubmed/12757910
Rouw, Romke and Scholte, H. Steven Increased structural connectivity in grapheme-color synesthesia.Nature Neuroscience. Volume 10 Number 6 June 2007. http://www.fmrib.ox.ac.uk/systems-plasticity/jc/potential-papers/rouw_2007.pdf
Russell R, Duchaine B, Nakayama K Super-recognizers: people with extraordinary face recognition ability.Psychonomic Bulletin and Review.2009 Apr;16(2):252-7. http://pbr.psychonomic-journals.org/content/16/2/252.full.pdf
Sacks, Oliver Oliver Sacks: What hallucination reveals about our minds. (lecture given Feb 2009) TED. http://www.ted.com/talks/oliver_sacks_what_hallucination_reveals_about_our_minds.html
Sacks, Oliver A neurologists’ notebook: face-blind.New Yorker. August 30th 2010. p. 36-?. http://www.newyorker.com/reporting/2010/08/30/100830fa_fact_sacks
Sacks, Oliver The mind’s eye. Picador, 2010. (chapter in this book titled “Face-Blind” p.82-110 is a longer version of the New Yorker article above)
Tomlinson, Eleanor K., Jones, Christopher A., Johnston, Robert A., Meaden, Alan, and Wink, Brian Facial emotion recognition from moving and static point-light images in schizophrenia. Schizophrenia Research. July 2006. Volume 85 Issue 1 p.96-105. http://www.schres-journal.com/article/S0920-9964(06)00098-3/abstract
Vuilleumier, Patrik, Mohr, Christine, Valenza, Nathalie, Wetzel, Corinne and Landis, Theodor Hyperfamiliarity for unknown faces after left lateral temporo‐occipital venous infarction: a double dissociation with prosopagnosia. Brain (2003) 126 (4): 889-907. doi: 10.1093/brain/awg086 http://brain.oxfordjournals.org/content/126/4/889.full
Weiss, Peter H. and Fink, Gereon R. Grapheme-colour synaesthetes show increased grey matter volumes of parietal and fusiform cortex. Brain (2009) 132 (1): 65-70. doi: 10.1093/brain/awn304 First published online: November 21, 2008. http://brain.oxfordjournals.org/content/132/1/65.full
Wikipedia contributors Delusional misidentification syndrome. Wikipedia, The Free Encyclopedia, http://en.wikipedia.org/w/index.php?title=Delusional_misidentification_syndrome&oldid=364074060
Wikipedia contributors Face perception. Wikipedia, The Free Encyclopedia, http://en.wikipedia.org/w/index.php?title=Face_perception&oldid=397226066
Wikipedia contributors Fusiform face area. Wikipedia, The Free Encyclopedia, http://en.wikipedia.org/w/index.php?title=Fusiform_face_area&oldid=378670842
Wikipedia contributors Fusiform gyrus. Wikipedia, The Free Encyclopedia, http://en.wikipedia.org/w/index.php?title=Fusiform_gyrus&oldid=400014320
Wikipedia contributors Hallucination. Wikipedia, The Free Encyclopedia.http://en.wikipedia.org/w/index.php?title=Hallucination&oldid=405603431
Wikipedia contributors Prosopagnosia.Wikipedia, The Free Encyclopedia,http://en.wikipedia.org/w/index.php?title=Prosopagnosia&oldid=400314172
Face recognition tests
MIT’s Face to Face Online Study http://facetoface.mit.edu/
“Test My Memory” from Faceblind.org Including “Online Cambridge Face Memory Test” and “Famous Faces” http://www.faceblind.org/facetests/
“Test My Brain” Including “Face Recognition, Emotion Perception, and Personality” and “Can you name that face?” and “Beauty and the eye of the beholder” http://www.testmybrain.org/
BBC Science Face Memory Test http://www.bbc.co.uk/science/humanbody/sleep/tmt/
Am I a super-recognizer? 
A Most Peculiar Experience
I don’t know about you, but my life has had more than a few strange moments. It is always hard to know what to say when a close friend “comes out”. There was the time when I got into trouble during a night dive on the reef. I’ll never forget meeting my complex and unusual mother-in-law for the first time at our wedding (and neither will our guests, no doubt). An aesthetically weird experience was listening to grotesquely distorted radio transmissions while touring the barren moonscape of low hills and salt flats surrounding Lake Eyre south, alone. After a while it seemed as though whispered words in a demonic voice could be discerned within the metallic noise. Working at a truck-stop in the middle of nowhere in the middle of 45 degree heat was quite an experience. There really are people in this world who enjoy a king-sized lime-flavoured milkshake. I’ve been many things and done a lot of places, or is that been many people and seen a lot of places? I’m not sure, but I’ve been around. In addition to the strange and challenging situations that any person who has lived a reasonably rounded life encounters, I also have odd experiences of a neurological nature. With the wisdom that only comes with maturity, I understand that nature has been kind to me, because she has done so much to make my life interesting.
The Strange Phenomenon
John* is a man who’s face I see at least once a week. John is a bit of a character, but I’ve got a lot of respect for John. John is not my friend or anything closer than that. John has an interesting face, and it attracts my attention when he is speaking. His face seems unusual in that it looks quite different when viewed from directly in front compared to how it looks viewed in profile. John has a facial feature that looks prominent in profile but looks like nothing much at all from a full-face view. This is almost like an optical illusion, and it gives John’s face quite a different “personality” when viewed from different angles. Visual curiosities like this grab my attention.
I’m not sure when it was that I first noticed “the strange phenomenon”. It has happened repeatedly over many months at least, possibly over a year. I know for sure that it was happening during the first half of 2010. While watching John (speaking or not speaking), if I was paying attention and also viewing his face from a position at around 45 degrees to the side (the only viewpoint that can capture the overall character of John’s face), and his face is also lit by natural sunlight, then, automatically and without warning, a very vivid memory of the face of Jean*, as she appeared years ago when I last saw her, viewed from exactly the same angle, would appear in my mind’s eye, sort of super-imposed over my real-time visual perception of John’s face. Once my memory of Jean and her face is “unlocked” in this way, memories come to mind about how she looked, and sometimes I recall the sound of her voice, which seems similar to John’s voice, in tone and also in emotional expression, even though there is the obvious gender difference. Maybe Jean is a bit less feminine than the average woman, but generally John and Jean seem pretty normal in terms of gender characteristics. I have never thought of them as androgynous. They both are intelligent adults and there is nothing blatantly strange in their manner or appearance. I have two theories about why this phenomenon is strongest at a 45 degree angle – this angle gives the best overview of a face, and also this view minimizes at least one gender difference between male and female faces. Men generally have broader faces than women, but this facial sexual dimorphism is minimized when viewed from the side.
I have never had this type of experience involving the faces of any other people – it only happens when I’m looking at John’s face. What’s so special about these people that they are the only faces that provoke this strange phenomenon? I will offer an explanation later. The short answer is that their faces look incredibly alike. As I remember her, Jean wore little of no makeup. I suspect that her resemblance to John might not have been as noticeable to me if she had worn enough makeup to make a difference to her facial appearance. It has been a number of years since I last saw Jean, so I don’t know if this strange phenomenon might work in reverse – with Jean’s face automatically evoking a visual memory of John’s. Jean’s face was the first of John and Jean’s faces that I ever saw. There is no overlap in time of the different periods of time when I’ve seen their faces regularly. At least five years separates these periods.
Who is Jean? Jean is a woman who served me over a counter, sometimes, at a place that I frequented for a few years about seven years ago. I haven’t (knowingly) seen her for years. I did not know her socially and I wouldn’t say we were particularly friendly (or unfriendly). At the time there was something in her manner and presentation that gave me the impression that there could be an unusual conservatism in her personality. I hardly remember Jean, except for those times when I see her face and hear her voice with stunning clarity in my memory. (Does that make sense?) I had not thought of Jean being in any way connected to John or resembling John before the strange phenomenon started happening. I just hadn’t seen the connection before. I have no record of Jean’s appearance besides my memory, and I don’t think I ever knew her surname. Jean and John would be roughly similar in age, but they are not siblings. I am not aware of any familial connection between them, but I also can’t be absolutely sure that none exists.
The strange phenomenon is a very orderly, sensitive and predictable thing. Conditions have to be “just right” for it to happen. If John’s face is not lit by sunlight, the phenomenon will not happen. If John has a big, beaming smile, it will not happen, but a more subtle smile sometimes does not block the phenomenon. If John looks inebriated or unusually emotional in some way, the phenomenon does not happen. When John gained weight, the phenomenon stopped. Excess weight distorts and covers some elements of the appearance of the face (and is also a health hazard). The strange phenomenon does not happen if I view John’s face from a profile view, and it rarely happens when his face is viewed from a full-face angle – it generally needs to be viewed from 45 degrees. The strange phenomenon requires viewing of John’s face in the right conditions for a few moments before it happens – it happens abruptly but not instantly.
Since I was a young child I have had synesthesia/synaesthesia. Synaesthesia is a common benign condition of the brain associated with an unusually rich network of connections in the white matter of the brain. Most cases are genetic in origin, and it runs in my family. One of the types of synaesthesia that I have, coloured letters and numbers, is associated with “extra activations in the fusiform gyrus” which is a part of the brain. The fusiform face area is the part of the brain that “does” face recognition. It is situated within the fusiform gyrus. It appears that there is something interesting going on in my fusiform gyrus. The strange phenomenon has many features in common with synaesthesia, and I believe it is an unusual type of synaesthesia. I believe the very specific image of John’s face seen under very specific conditions is an inducer, trigger or stimulus of my synaesthesia, and my remembered image of Jean’s face is the concurrent or additional sensory experience in my synaesthesia. Like synaesthesia, the strange phenomenon is automatic. It is not something that I “do” intentionally or wish to happen, although I find it amusing to anticipate it and then see it happen. I am sure I would be unable to prevent it by conscious will from happening. Like synaesthesia, the phenomenon is reliable. Given exactly the right conditions, it will happen.
What does the strange phenomenon feel like? The normal process that this phenomenon most feels like is face recognition, but with the twist that my mind “changes its mind” about who it is looking at. It feels as though at first my mind normally recognizes the face as John’s, with no fuss, but then it seems to impose a different interpretation, dredging up Jean as a better answer to the question of “Who is the owner of this face?” I’ve wondered why my mind should be so willing to abnormally review its original correct decision. I can only guess that there is some mechanism in the brain that gives precedence to much older face memories when choosing between very similar-looking stored memories of faces during the process of identifying a currently seen face. Alternately, my brain, and all brains, might be designed to identify not only the faces of individuals, but also to identify similarities betweenpeople’s faces, as a clue to genetic relatedness. I know enough about biology and evolution to know that intelligent animals such as humans are likely to have evolved features to help us to identify our kin and kinship between others.
Does the strange phenomenon cause emotional distress? Not to me, but it is a weird experience. Many of the types of synaesthesia that I experience are so unobtrusive and fleeting that they can go unnoted, and some types are so predictable that they feel completely ordinary. In my experience it is the types of synaesthesia that are rarely experienced and are person-triggered that are the most startling and subjectively weird. The strange phenomenon fits into both categories. It is these experiences that can make one think “WTF?” or “S*** a brick!” or “That is the strangest thing!” (to quote the title of a book about synaesthesia).
Viewing people’s faces is obviously a social-type experience. As anyone would, I feel as though I am witnessing moods and personalities when I view faces. I wouldn’t be surprised if John and Jean turned out to have similar personalities, but at the same time, I don’t feel that I can read Jean or John “like a book”.
When John gained weight the appearance of his face changed and the strange phenomenon stopped. This is not the first time that a type of synaesthesia that I’ve experienced that is triggered by particular characteristics of a person has been extinguished by a change in that person. This possibly gives me a greater appreciation of time and people, and the brevity of childhood and life in general.
There are many reasons why I believe that this strange phenomenon is interesting and unusual. It seems to be a mixture of synaesthesia, ordinary remembering and face recognition, and I’m sure this is an unusual thing. The strange phenomenon differs from ordinary remembering in many ways. It requires a very specific visual trigger, it happens repeatedly and reliably, like synaesthesia it relies on attention but is otherwise independent of conscious control, and it evokes a vivid memory of the face of a person who shouldn’t be memorable to me. This phenomenon is one of two different types of synaesthesia that I experience which automatically “unlock” vivid and often very old visual memories, giving extraordinary glimpses into a world of visual memories that are apparently stored away in my mind like photos or videotapes, but can only rarely be accessed.
Significantly, the other type of synaesthesia of mine which gives spontaneous vivid mental images evokes my memories of specific places (not people) that I have visited in the past, but which often aren’t particularly memorable. These “visions” of places look as they did last time I saw them, frozen in time. I “see” places (in my mind’s eye) that have since been demolished, and some of these images date back to scenes my early childhood. These involuntarily recalled visual memories of places are only visual experiences, they do not involve smells or sounds or other non-visual types of sensory experience. There appears to be a neurological link between the recognition of faces and the recognition of places, with disability in recognizing both of these types of things found together in some people. The famous neurologist and author Dr Oliver Sacks is one person who has prosopagnosia (a disability in recognizing faces) and also a disability in recognizing places. There appear to be two different scientific terms in use for this neurologically-based inability to recognize scenes: “agnosia for scenes” (seen in a New Scientist article) and “topographical agnosia” (Sacks 2010). In a recent article published in New Yorker magazine, and also in his recent book The Mind’s Eye, Dr Sacks described his problems with getting lost in the streets after unknowingly walking past his own house a number of times, and also being unable to recognize people he knows well. The British primatologist Dame Jane Goodall is another famous person who has trouble recognizing faces and also places. Faces and places are the only types of things that I receive spontaneous “visions” of. I am sure this is no mere coincidence. Like the strange phenomenon, I find it amusing to anticipate receiving a “vision” of a place when the conditions are just right, and then watching it appear, suddenly, and for no logical reason.
My strange phenomenon has two features which I believe make the strange phenomenon truly strange: it involves effortless mental processing of a task that should be rather difficult (sorting through a lifetime of memories of countless faces, then matching two faces of people of different genders that look very similar from angles which give a view that is least affected by sexual dimorphism), and the strange phenomenon also manifests as a very vivid image in the mind’s eye (language and words have no role in this phenomenon).
I have grapheme-colour synaesthesia and I am closely related to people who also have this type of synaesthesia and who have also been formally offered places, more than once, to gifted and talented educational programs. I believe there is a connection between the synaesthesia and the smarts. I am also in a family that has at least four generations of people who have particular talents in the areas of English and foreign languages (grapheme-colour synaesthetes are among this group). I believe it is possible that which ever genes give rise to grapheme-colour synaesthesia and related cognitive differences could be evolutionary adaptations that give an advantage in learning languages and reading. I believe it could be as simple as a gene that boosts the development of visual memory, for words, letters and also faces.
I am not aware of any description in the scientific or popular literature of an experience that is genuinely the same type of thing as the strange phenomenon. This does not make me doubt the reality of what I have experienced. I would expect that this would be a rare phenomenon, because it is the result of a combination of some most unusual factors – two different observations of a quietly unusual pair of people, separated by a very long period of time, observed by another unusual person, who has the interest in scientific matters and the inclination to try to make sense of it all. Rare things do happen, but not very often.
*Not their real names. Obviously, the true identities of John and Jean cannot be divulged.
Alternative ways of categorizing the strange phenomenon/competing explanations
Is it just an idiosyncratic and meaningless connection between two things due to synaesthesia?
I don’t think so. The two people objectively do look similar, so the link does not seem to be random or accidental. It’s not as though the sight of a face make me hear a sound or see a colour, the strange phenomenon only involves faces.
Is the phenomenon just the simple remembering of a similar-looking face?
No, it is different, because it is much less influenced by conscious control than simple remembering, and the memories evoked are more vivid and extensive than can be retrieved by conscious effort at remembering. Perhaps one could describe the strange phenomenon as face recognition that is “turbocharged” with synaesthesia. The strange phenomenon feels strange, because it makes me see a similarity between two faces and two people that doesn’t seem to make sense – they can’t be identical twins, because one is male and one female.
Is the phenomenon an experience typical of those of “super-recognizers”?
No, but there are many similarities. Super-recognizers report being able to recognize people who were last met many years ago and were not more than a fleeting acquaintance. My remembering Jean is like this. Super-recognizers also are able to recognize despite changes in appearance such as child to adult transition and changes of hairstyle. My recognizing of similarities in faces of different genders is similar to this. The phenomenon feels like face recognition. I have already completed some tests of face recognition ability that are readily accessible through the internet, and I got perfect scores, which could indicate that I’m a super-recognizer.
Is the phenomenon like one of those uncanny moments of noticing a family resemblance, like noticing a grandparent’s frown in a young child?
It is similar to this in that it involves similar-looking people but it also transcends stuff like gender and age, but noticing family resemblances is different in that it is unpredictable, occasional, is typically triggered by gestures or expressions, and does not typically unlock a cache of hidden memories. The strange phenomenon seems to involve the whole face, not a part of the face.
Is this phenomenon a case of mistaken identity with two very similar-looking people, in an unusual situation? (as might happen when meeting the identical twin of a person that one already knows)
This explanation seems applicable in some ways but isn’t. John and Jean do look similar, when viewed from a certain angle, but there is no mistaken identity. All the way through the strange phenomenon my conscious mind is clear about who is who, the identity confusion happens on a more primitive level. I’ve known two sets of identical twins in my past. I never liked any of them enough to care which was which.
Is the phenomenon like recognizing a previously known genetic syndrome in a number of different people, such as identifying that a stranger has Down syndrome?
The phenomenon is similar to this in that it transcends stuff like age and gender. Identifying a person as having Down syndrome is different in that (for me) it is not a strange experience and does not evoke visual memories of individuals seen in the past. I believe my brain treats Down syndrome in a similar way that it treats racial differences. Perhaps my brain would act more oddly when confronted with people who have a genetic syndrome that is not fairly common, familiar and obvious. I think it is likely that John and Jean have the same rare genetic syndrome, but I don’t know what it might be. There is more to this story than I’ve set out here.
Is the phenomenon Synaesthesia?
I believe it is. It is reliable, repetitive, automatic and involuntary like synaesthesia. I cannot voluntarily access my memories of Jean as fully as happens in the phenomenon. It does not require or involve effort. Like synaesthesia it requires paying attention to the trigger. It is sensory (visual). It involves a very specific trigger evoking a very specific experience, like synaesthesia. It happens suddenly and without warning. It “hits you”. Some types of synaesthesia are like this. It involves memory, and synesthetes are thought to have superior memory.
Why do you ask and answer your own questions?
I’m not sure, but it works for me.
Some explanations that I believe are NOT applicable
Some type of delusional misidentification syndrome (DMS)
There are many different recognized types of delusional syndromes that involve incorrect identification of people, and some are thought to be due to faulty face recognition or perception. I have carefully considered all of the DMS’s listed at the Wikipedia, and none of them describe the same situation as the strange phenomenon. The only type of DMS that I have heard of that is in any way similar to it is something that Dr Oliver Sacks described in his article in New Yorker, a hyperfamiliarity for faces that Sacks claims was described by Devinsky (Sacks gives no reference in this article). Sacks describes a disorder in which everyone feels familiar to a person with the disorder, and the person with the delusion might approach strangers and address them as though they are old friends. I do not do this. Even if I was a more extroverted person, I would not do this because I do not have a feeling of familiarity for masses of other people. I believe there is nothing wrong with my ability to tell the difference between faces that I have never seen, and those that I have seen in the past. I can’t imagine what it would be like to walk into a room of people and feel like I was surrounded by old friends. That doesn’t sound like me at all! I’ve had a read of the 2002-2003 journal paper by Vuilleumier et al about a case of hyperfamiliarity for unknown faces. I do not believe I have anything in common with the patient described, except that we both have good face recognition abilities (the title of the paper appears to be a typo). Neither John nor Jean were unfamiliar to me during the time when the strange phenomenon started. Their faces were and are not unfamiliar faces.
The simple fact that I was able to get some perfect scores in scientifically credible tests of face recognition surely shows that I do not have a fault in my face recognition brain “hardware”. I wouldn’t expect a delusional syndrome to be associated with a very high level of ability.
Out of curiousity I did a face memory test that I found at the website of the BBC. I do not know anything about who created this test, but it can be found here: http://www.bbc.co.uk/science/humanbody/sleep/tmt/ I got a perfect score for face recognition, a score of 91% for temporal memory associated with face memory (average score 68%) and a low number of false-positive identifications. I think the fact that I scored very low (one, caused by a misunderstanding of the question) for false-positive identifications shows that my identification of faces in general isn’t influenced by some hyperfamiliarity, misidentification or delusion disorder. I don’t have a general problem with seeing unfamiliar faces as familiar.
There is one area of cognition in which I do possibly have an abnormal sensation of false familiarity. You could call it “dialogue déjà vu”. It is associated with things that I write or say to other people. I might write a note or tell a story to someone else, and immediately after I might feel that it is too familiar, and I wonder whether I have already told that person in the past. The result is that I never feel completely confident about judging if I’ve already had a conversation or informed someone about something, and I annoy family sometimes by telling the same story twice.
A visual disturbance or vision defect
There are some interesting and exotic types of visual disturbances, but they do not adequately explain the strange phenomenon, because it only happens when I see the face of one particular person under very specific conditions. No visual disturbance or defect in vision could be this selective. I have had glasses for short-sightedness since I was a teen, but I only really need to wear them for driving at night. Small print is getting harder to read as I age, and my colour vision at night isn’t perfect, but I regard my vision as pretty normal for my age. As a synaesthete who experiences visual manifestations of synaesthesia as appearing in my mind’s eye, and not projected into space around me, I am well aware of the difference between things seen through my eyes and things seen within, in my mind, memory or imagination. Jean’s face is seen in my mind’s eye – her face is not a defective image originating from my eye.
How blind could I be if I am able to get perfect scores on tests of face recognition ability?
Hallucination
Here are definitions of “hallucination” from three different sources:
Famous neurologist, author and prosopagnosic Oliver Sacks quoted from his Feb 2009 TED talk about hallucinations:
“They don’t seem to be of our creation. They don’t seem to be under our control. They seem to be from the outside, and [seem] to mimic perception.”
Clinical Senior Lecturer and Honorary Consultant Psychiatrist Dominic Ffytche in a 2004 clinical guide to visual hallucination and illusion disorders, on the difference between visual images and hallucinations:
“Visual images appear in the mind’s eye and are under some degree of volitional control, as opposed to hallucinations and illusions which are externally located, unpredictable and outside volition (in the sense that one cannot choose to make a hallucination of, say, a face turn into that of a chair).”
Wikipedia article titled “Hallucination”
“A hallucination, in the broadest sense of the word, is a perception in the absence of a stimulus. In a stricter sense, hallucinations are defined as perceptions in a conscious and awake state in the absence of external stimuli which have qualities of real perception, in that they are vivid, substantial, and located in external objective space.”
The Strange Phenomenon does not fall under the definition of hallucination for two reasons – because it is not percieved or located externally, it is in the mind’s eye, and it does not happen in the absence of a stimulus, the stimulus is the visual perception of John’s face as seen under very specific conditions. This is not a conventional stimulus, it is a synaesthesia-type stimulus.
Psychosis
I do not know what psychosis or insanity are like, as I’ve been fortunate enough throughout my life to never have had such experiences, but I’m sure that such disorders of the mind would not manifest with the great precision, order and rarity of the strange phenomenon. I do not live a disordered life. I have no demerit points on my driver’s licence.
Apparently “It is well established that schizophrenia is associated with difficulties recognising facial expressions of emotion.” (abstract of Tomlinson et al 2006). I have done a test of identifying facial expressions of emotion, the Reading the Mind in the Eyes Test, and I got a score of 33 out of 36, which indicates that I am “…very accurate at decoding a person’s facial expressions around their eyes.” So I guess that means it is highly unlikely that I have schizoprenia.
Recreational drug effects
The same comments apply as those for psychosis. I do not regularly take any prescription, alternative medicine or illicit drugs, except caffeine and the odd aspirin. I rarely drink alcohol. I do not get any effect like the strange phenomenon from any drug or alcohol. Synaesthetes don’t need drugs!
Epilepsy (including reflex epilepsy)
I do not have this diagnosis. There is no shaking or loss of consciousness associated with the strange phenomenon.
Migraine Aura
Headaches are not associated with the strange phenomenon. I sometimes get super-acute senses with a headache, but nothing associated with “visions”, visual disturbance or face recognition.
Illness, fever, sleep deprivation, fatigue, delirium
Not applicable. The strange phenomenon has been happening over a very long period of time.
Religious or supernatural “vision”
I’ve been an atheist rationalist for most of my life. This type of thing doesn’t happen to me. God doesn’t care about me, and the feeling is mutual.
References and recommended reading
Ffytche, DominicVisual Hallucination and Illusion Disorders: A Clinical Guide.ACNR. VOLUME 4 NUMBER 2 MAY/JUNE 2004. p. 16-18.http://www.acnr.co.uk/pdfs/volume4issue2/v4i2reviewart3.pdf
Jäncke L, Beeli G, Eulig C, Hänggi J. The neuroanatomy of grapheme-color synesthesia.Eur J Neuroscience. 2009 Mar;29(6):1287-93. http://www.ncbi.nlm.nih.gov/pubmed/19302164
Lambert, Craig Facial pheenoms. Harvard Magazine. September-October 2009. http://harvardmagazine.com/2009/09/facial-pheenoms
Mendez, MF, Cherrier, MM Agnosia for scenes in topographagnosia. Neuropsychologia.2003;41(10):1387-95. http://www.ncbi.nlm.nih.gov/pubmed/12757910
Rouw, Romke and Scholte, H. Steven Increased structural connectivity in grapheme-color synesthesia.Nature Neuroscience. Volume 10 Number 6 June 2007. http://www.fmrib.ox.ac.uk/systems-plasticity/jc/potential-papers/rouw_2007.pdf
Russell R, Duchaine B, Nakayama K Super-recognizers: people with extraordinary face recognition ability.Psychonomic Bulletin and Review.2009 Apr;16(2):252-7. http://pbr.psychonomic-journals.org/content/16/2/252.full.pdf
Sacks, Oliver Oliver Sacks: What hallucination reveals about our minds. (lecture given Feb 2009) TED. http://www.ted.com/talks/oliver_sacks_what_hallucination_reveals_about_our_minds.html
Sacks, Oliver A neurologists’ notebook: face-blind.New Yorker. August 30th 2010. p. 36-?. http://www.newyorker.com/reporting/2010/08/30/100830fa_fact_sacks
Sacks, Oliver The mind’s eye. Picador, 2010. (chapter in this book titled “Face-Blind” p.82-110 is a longer version of the New Yorker article above)
Tomlinson, Eleanor K., Jones, Christopher A., Johnston, Robert A., Meaden, Alan, and Wink, Brian Facial emotion recognition from moving and static point-light images in schizophrenia. Schizophrenia Research. July 2006. Volume 85 Issue 1 p.96-105. http://www.schres-journal.com/article/S0920-9964(06)00098-3/abstract
Vuilleumier, Patrik, Mohr, Christine, Valenza, Nathalie, Wetzel, Corinne and Landis, Theodor Hyperfamiliarity for unknown faces after left lateral temporo‐occipital venous infarction: a double dissociation with prosopagnosia. Brain (2003) 126 (4): 889-907. doi: 10.1093/brain/awg086 http://brain.oxfordjournals.org/content/126/4/889.full
Weiss, Peter H. and Fink, Gereon R. Grapheme-colour synaesthetes show increased grey matter volumes of parietal and fusiform cortex. Brain (2009) 132 (1): 65-70. doi: 10.1093/brain/awn304 First published online: November 21, 2008. http://brain.oxfordjournals.org/content/132/1/65.full
Wikipedia contributors Delusional misidentification syndrome. Wikipedia, The Free Encyclopedia, http://en.wikipedia.org/w/index.php?title=Delusional_misidentification_syndrome&oldid=364074060
Wikipedia contributors Face perception. Wikipedia, The Free Encyclopedia, http://en.wikipedia.org/w/index.php?title=Face_perception&oldid=397226066
Wikipedia contributors Fusiform face area. Wikipedia, The Free Encyclopedia, http://en.wikipedia.org/w/index.php?title=Fusiform_face_area&oldid=378670842
Wikipedia contributors Fusiform gyrus. Wikipedia, The Free Encyclopedia, http://en.wikipedia.org/w/index.php?title=Fusiform_gyrus&oldid=400014320
Wikipedia contributors Hallucination. Wikipedia, The Free Encyclopedia.http://en.wikipedia.org/w/index.php?title=Hallucination&oldid=405603431
Wikipedia contributors Prosopagnosia.Wikipedia, The Free Encyclopedia,http://en.wikipedia.org/w/index.php?title=Prosopagnosia&oldid=400314172
Face recognition tests
MIT’s Face to Face Online Study http://facetoface.mit.edu/
“Test My Memory” from Faceblind.org Including “Online Cambridge Face Memory Test” and “Famous Faces” http://www.faceblind.org/facetests/
“Test My Brain” Including “Face Recognition, Emotion Perception, and Personality” and “Can you name that face?” and “Beauty and the eye of the beholder” http://www.testmybrain.org/
BBC Science Face Memory Test http://www.bbc.co.uk/science/humanbody/sleep/tmt/