Photographic/Eidetic Memory

 that it must be difficult to assert the legitimacy of data you have collected when that data was obtained from a single subject who you then married and who has never been tested a second time even by yourself to replicate that finding.  Admitting that your finding may be unique and that the phenomenon you observed may not exist outside of that single case seems like a lame attempt to preserve your skepticism and empiricism.  But in a field of study like photographic memory hard science is apparently hard to come by and the occasional incredible case study and by depictions in the media that dramatically overstate the capacity to remember.  The appeal of photographic memory, however, is very easy to understand and very close to the fundamental appeal of science as a potential route to the fantastic. 

            The idea that improvements in visual memory or in some other area of brain function may be the result of a neuroplastic adaptation to a deficit is interesting, and almost makes sense logically.  It’s possible that the brain develops an increased focus upon the visual in order to attempt to overcome the lack of more natural interpretations of social situations and of non-verbal communication, providing the individual with a longer period of time to make interpretations. This brings things back full circle to the idea of focusing on strengths rather than weaknesses and viewing mental disorders as a result of an atypical organization of the brain that may result in as many positive changes as it does negative. 

This was an interesting discussion. I hadn't given much thought to the concept of photographic, or eidetic, memory before. After reading the articles and discussing the concept further in class, I realized that I don't think photographic memory exists. I don't believe that any image can be preserved and stored as an accurate representation of "reality". Further, I believe that there is no evolutionary advantage to eidetic memory. In fact, one of the Scientific American articles even said that "eidetic images are certainly not photographic in nature but instead are reconstructed from memory and can be influenced by other memories (both visual and nonvisual) by cognitive biases and expectations" (Is there such..., 2007). So there is just as much distortion in the eidetic images as there are in other short- and long-term memories. This article basically says there is no such thing as photographic memory and I agree.

The article also said that children are usually the ones who are identified as having a photographic memory. How do the children even report this phenomenon? The article further explains that some researchers believe that "eidetic imagery occurs more frequently in certain populations of the mentally retarded (specifically, in individuals whose retardation most likely stems from biological, rather than environmental, causes) and also among geriatric populations" (Is there such..., 2007). Children, old people, and the mentally impaired; what is it about these populations that make them more prone to experiencing "eidetic" imagery anyway?

 
Thanks for the interesting discussion last week! I definitely agree with the viewpoint that photographic memory is not adaptive. I can’t fathom a rational purpose for having this ability. Photographic memory presumably takes more effort for the brain to maintain and seems unreliable over time- maybe even more so than regular long-term memory. Storing a complete image of something is not as useful as say storing a template of something. We remember things in order to guide us through similar situations in the future. No two situations are completely the same down to every last detail. Depending on a photographic memory therefore may be an inconvenient way of life. Mentally storing a reference template takes up less brain energy and capacity. Mental templates or patterned expectations are applicable in an infinite number of situations as well, whereas a photographic image is only useful for exactly what is present in the image. In a way photographic memory is more of a “now” mechanism while more common types of memory and template storing are wholly “future” oriented.
 
Of course, this is even assuming photographic memory, the cultural phenomenon as we know it, even exists! I am still unsure if I believe that photographic memory is real. The small sample size of individuals who may even have this type of memory into adulthood makes photographic memory a dubious ability. Those individuals that claim to have photographic memory are almost always debunked as using some other type of mental mechanism. For example, the Russian journalist mentioned in the Slate article was known for having an unbelievable photographic/ borderline savant memory. However, we luckily found out that he was just really good at devising mnemonic devices. Phew! Overall, I think photographic memory does not exist as we, as a society, would like it to. Instead it is more of an unattainable ideal, that even if it does exist, we will not rest until we can blame it on other reasons in order to make the mythical perfection of photographic memory live on. Why ruin the magic?
 

After this week's discussion, I found myself wondering about the usefulness of photographic memory.  We discussed whether or not Stephen Wiltshire would be able to navigate the cities that he drew, using the "map" that he created in his head.  We seemed to agree that what he is doing is not exactly photographic memory, but it is certainly a similar concept: being able to look at something and hold it in one's mind.  I wonder if he could reproduce those same cities after extended periods of time.  For example, could he look at Rome, draw Rome, then a few weeks later look at Tokyo, draw Tokyo, and then draw Rome again from memory?  Eidetic images seem fade away after a given amount of time; is this the way that Stephen Wiltshire's brain works too?  If it is, can photographic memory be defined as simply a gift for memorization on a much larger scale than normal?  We have all had the experience of studying for a test, memorizing all of the information necessary, and then being unable to remember that information a few weeks or months later.  Most of the photographic memory tests seem to be testing memorization ability; on the other hand, people with eidetic memory seem to be able to actually see an image after the image is no longer there. 

Like Sasha, I have also been wondering about the evolutionary advantages of eidetic memory or photographic memory.  There are people who can remember every moment of their lives, but these people are miserable.  Most people seem to feel as if we all have a finite amount of brain space.  Once that space is filled, something must be forgotten in order to remember something new.  People who can remember their entire lives would seem to have infinite brain space; does this have something to do with photographic memory?  I can't help but think that if it was evolutionarily advantageous to have a photographic memory and infinite brain space, then it wouldn't be so rare.

One question that really intrigued me last week was whether or not after going on a helicopter ride or drawing his panorama's, if Stephen Wiltshire could actively find his way around the cities he drew with such detail from memory. After searching the internets for a while i couldn't really find an answer to this question so I'm still very curious. I guess this relates to my question of how "valuable" is it to have such an incredible memory? In Wiltshire's case, is he able to interpret what he is seeing and drawing and is there any meaning to him? After drawing a panorama of Rome can Wiltshire think to himself, 'if i want to go from the St. Peter's Basilica to the Pantheon I have to travel south east, cross over the tiber river and then walk down via dei coronari and then turn right at corso del rinasciemento and then after a block take another right and walk straight and i'll be there. Step by step directions may be asking too much- but the ability to have a general idea of how to get from point A to point B is what I'm looking for. Still, Wiltshire is able to label the small streets and alleys, so if he can memorize that much detail it would be interesting to see how well he could use it by means of recalling and interpreting his surroundings as opposed to drawing an aerial view panorama. I personally think that memory is mostly valuable in so far as you can gain meaning from your memories, you can use your memories to learn something, to do something. Memory is an important part of the learning process, but if you aren't capable of deriving anything more than the superficial from your memories then there's a limit as to how much you can really learn and grow. While I am certainly incredibly impressed by Stephen Wiltshire's ability to draw these incredible panoramas of cities from memory, what I would really like to know is what he does with those memories after he finishes his panorama.

I'm quite intrigued by the "ability within disability" explanation for Wiltshire's amazing memory for drawing cityscapes, buildings, etc. I have begun to question, however, whether the mechanism he uses for memory is simply a heightened form of the one those people without exceptional memories use, or is it a different one entirely? One of the ways we try to remember numbers is by blocking - for example, we remember a phone number by grouping it into subsets of smaller, more manageable groups -- instead of "6108961000," we remember the number as 610-896-1000. Also, we can more easily remember characteristics or words by grouping them into categories: brown, high, green, blue, hazel, leafy, tall --> we would be better able to remember those words if we classified them according to eye color (brown, green, blue, hazel) and characteristics of trees (leafy, tall, high, green). Does Steven Wiltshire use these categorizing and blocking techniques to remember things more efficiently? Or is his seemingly "photographic" or eidetic memory an entirely different mechanism or phenomenon? I'm inclined to think that no matter how sophisticated a blocking technique I used, there would be no way I could remember even how to draw one building exactly, let alone a panorama of Rome or Tokyo. So at least in terms of photographic/eidetic memory within a disability, I think it occurs because of a different mechanism.

When we think about new found abilities within disabilities (i.e. savant syndrome), how and why are they occurring? Do they happen differently in different situations? Is memory of numbers (i.e. extreme digits of Pi) due to the blocking phenomenon, while Witshire-esque drawing reproductions require a different mechanism entirely from normal memory? And if certain new found abilities require different mechanism, how do these new mechanisms arise? Are they evolutionary artifacts that "normal" individuals just don't harness? Or are they a characteristic of the illness?

Bobby brought up the point last night that, because Wiltshire's is autistic, the amount we can learn about normal visual memory through his ability is limited.  This seems true; it may be misleading to draw conclusions about normal memory by observing the functions of a brain that is fundamentally different. However, I can think of two possible reasons to believe that we could still learn about normal brain function through case studies such as Wiltshire's. For one, while I don't pretend to know much about autism, I have heard several theories suggesting that those with autism share similar neural circuitry with "normal" people, but represent the extremes of certain spectrums. For example, I remember learning about a particularly contentious theory that the autistic brain is only a more extremely masculinized brain (less emotional, more rational [you can see why this was contentious], etc.). If this is true -- if autism does in fact only signify an extreme form of normal circuitry -- then perhaps we can learn about normal brain functioning through Wilkshire. His spectacular ability could be understood as only a more extreme version of what all people have, given that his functions inhere in similar but extreme circuitry.

A second reason that we may be able to generalize instances of photographic/eidetic memory to normal functioning relates to another point brought up last night. We each have some degree of eidetic memory; as pointed out, we know where a quotation we're looking for resides on the page. Moreover, as far as I understand, the current model of normal memory processes involves a short period of sensory memory, prior even to short term memory. If accessed quickly enough, we can scan this transient sensory image in a similar way to those with eidetic memory. This suggests that instances of photographic memory (or at least eidetic memory) may only serve as extreme forms of mechanisms we all have access to. Should eidetic memory only be an extreme case of normal memory, we may expect to learn about normal memory through instances of this phenomenon.