Since the perception and remembrance of motion are closely related to procedural long-term memory, the capacity of our memory may be increased through practice. For many students, retaining information in working memory is not enough. Working memory can only hold a limited amount of knowledge, and less when the brain is under stress or fatigue.
A greater problem is that working memory is fleeting. In order to be able to retrieve the memory days later, we have to turn short-term memories into long-term ones. In the past, people used the repetition of information combined with mnemonic skills to consolidate their memories. Remembering the acronyms of several items, creatively linking the material with songs or images, and repetition and revision of the materials all help to consolidate the memory.
The question that arises here is how we can assess the effectiveness of the consolidation tools. In , Ericsson proposed three requirements for good memory skills 13 : 1 meaningful encoding, 2 retrieval structure, and 3 speed-up.
Cues such as visual images or rhyming words should also be stored with the memory. The more imaginative and elaborate the cues are, the easier it is to retrieve the associated memories. Although the exploration into memory consolidation skills took place long before Ricci Matteo embarked on his missionary trip to the Ming dynasty, scientists only began to discover the biological process of memory consolidation in recent decades.
The process of memory consolidation originates in the hippocampus, which later transfers the memories to other parts of the cerebral cortex for long-term storage Information in our brain is transported through neurons.
Mammalian neurons communicate by releasing neurotransmitters-molecules that travel in the small space, also known as the synapse, between two neurons. Experiments have found that when a strong external stimulus is applied to the synapse, the synapse is made more sensitive so that the communicating neurons may be more responsive to future release of neurotransmitter, or release a larger quantity of neurotransmitter. Such increase in the synaptic strength is often related to the improvement of mammalian memory This process of long lasting enhancement in signal transmission following stimulation of the synapse is termed long term potentiation LTP.
LTP has proven to be the most viable candidate so far for a cellular mechanism of memory storage LTP is thus the important linkage between our philosophical understanding and the biophysical aspect of our memory and learning. Since the discovery of LTP, huge advances have been made in understanding exactly how it works.
The major transmitter in the brain is glutamate, which when released binds to AMPA receptors across the synapse, causing positively charged ions to rush into the cell. If enough receptors are stimulated by glutamate, a threshold charge will build up inside the cell, and the neuron will pass the signal on down the network.
LTP works by increasing the amount of receptors available to detect glutamate release, so that the next time the same stimulus comes around it will pass the signal on even more easily. For example, if you have a bad reaction to shellfish one day, your neurons will undergo LTP so that you will never go near shellfish again. The implication of the aforementioned experiments is that neuropsychologists may be able to control LTP using pharmachology and specific stimulation.
If that is possible, all the memory tricks we used in the past pale in comparison to the potential of targeted LTP stimulating. LTP may allow working memories to be stored as long-term memories with much more speed and accuracy than traditional mnemonic skills. However, to control human memory, or even to totally dissect and understand mammalian intelligence will demand a long period of strenuous scientific endeavor.
While research into the storage of memory and the processing of information in the human brain still remains rather rudimentary, potential LTP memory treatments provide amnesic patients hope. Perhaps one day, scientists will be able to create our Memory Bread and attain perfect photographic long-term memory for all of us.
Roediger III, Y. Dubai, S. Atkinson, R. Squire, Neurobiol. Illustration of Brain Anatomy Squire, C. Stark, R. Clark, Annu. First, an eidetic image is not simply a long afterimage, since afterimages move around when you move your eyes and are usually a different color than the original image. For example, a flash camera can produce afterimages: the flash is bright white, but the afterimage is a black dot, and the dot moves around every time you move your eyes.
In contrast, a true eidetic image doesnt move as you move your eyes, and it is in the same color as the original picture.
Second, a common visual image that we can all create from memory such as an image of a bedroom does not have the characteristics of most eidetic images, which almost always fade away involuntarily and part by part.
Also, it is not possible to control which parts of an eidetic image fade and which remain visible. Unlike common visual images created from memory, most eidetic images last between about half a minute to several minutes only, and it is possible to voluntarily destroy an eidetic image forever by the simple act of blinking intentionally.
Furthermore, once gone from view, rarely can an eidetic image ever be retrieved. You might expect that an individual who claims to still see a picture after it has been removed would be able to have a perfect memory of the original picture. After all, a perfect memory is what is usually implied by the commonly used phrase "photographic memory. In fact, besides often being sketchy on some details, it is not unusual for eidetikers to alter visual details and even to invent some that were never in the original.
This suggests that eidetic images are certainly not photographic in nature but instead are reconstructed from memory and can be influenced like other memories both visual and nonvisual by cognitive biases and expectations.
The vast majority of the people who have been identified as possessing eidetic imagery are children. The prevalence estimates of the ability among preadolescents range from about 2 percent to 10 percent.
And it is an equal-opportunity phenomenon--theres no gender difference in who is likely to be an eidetiker. Although it is certainly controversial, some researchers also 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.
With a few notable exceptions, however, most research has shown that virtually no adults seem to possess the ability to form eidetic images. Why should this be so? Various parts of the brain mature at different times, and adolescence is a major time for such changes.
It's possible Mr. Gordon's ability took a big jump around his 16th birthday, but it's also possible he noticed it only then. Gordon might want to have formal testing, to see just how good his memory is and in what areas. Then we can debate the nature-nurture question from harder evidence.
This article was originally published with the title "I developed what appears to be a photographic memory when I was 16 years old. Already a subscriber? Sign in. Thanks for reading Scientific American. Create your free account or Sign in to continue. See Subscription Options. Go Paperless with Digital.
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