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Things You Need to Know About Hyperthymesia

Nicks J
People affected with hyperthymesia tend to have an extensive memory about events that are of personal significance. Their ability to remember events, no matter how insignificant, is exceptionally good.

Did You Know?

According to a study conducted by researchers at the University of California, Ervine, in 2012, there were twelve known individuals around the world that exhibited highly superior autobiographical memory (HSAM) or hyperthymesia.
What would you say about a person who can effortlessly recall his past experiences, (no matter how trivial they are) in great detail, that occurred on a particular day some 15 years ago? Probably, a person with extraordinary memory. Hyperthymesia is the scientific term used to describe this superior type of memory.
We all have the ability to recall things, particularly those that had a serious impact on our life. Our personal pasts are filled with events that are many times irrelevant and have no recalling value.
However, individuals diagnosed with hyperthymesia tend to show exceptionally high recalling ability, meaning they can vividly remember their personal experiences , even the minutest details, in the past.
Hyperthymesia is a neurological condition with no known cause, in which the person shows the capacity to remember things in great detail. For instance, he can tell the clothes he had worn and the people he met on a particular day, say December 15, 2005.
Now this date may not have any special significance, yet he is able to recall things in extreme detail. The day of the week on which this date occurred can also be easily recalled by hyperthymestic individuals.

Features of Hyperthymesia

People affected with this condition can remember decades-old events (relevant or insignificant) very quickly. This means small things like what was eaten on that day can be recalled easily without any effort.
Although hyperthymestic people are able to easily recall things of the past, the memories are only related to their life. So these individuals do not remember past events that are pertaining to someone else's life. Hence, this condition is also referred to as highly superior autobiographical memory (HSAM), since the memory keeps a tab of events that are of personal importance.
There are hyperthymestic individuals who can literally recall what happened on every single day of their life, since they were 10 years old.
Their autobiographical memory is remarkably good but the same thing cannot be said about their ability to memorize. To put it simply, their rote memorization skills are somewhat average. They are also found to perform ordinarily in standard memory tests.
Since people affected with hyperthymesia do not have to take any effort in recalling events, it is different from other types of exceptional memory that is usually developed using mnemonic devices.
Hyperthymesia can have a negative impact on their thinking and reasoning ability, since these individuals unknowingly tend to think a lot about past events, leaving very little scope for planning about the future. It appears as if they are in some other world, wherein they are continuously thinking about their personal past.


An MRI head scan of an individual diagnosed with hyperthymesia has shown that the parts of the brain, critical for memory function, were found to be larger than normal. For instance, the caudate nucleus and temporal lobe of the brain that have been associated with memory encoding and storage showed some degree of enlargement.
This unique neurodevelopment observed in the individual is believed to be responsible for his exceptional memory skills.

Another theory suggested is that the memory in these individuals is stored using semantic encoding. This method of encoding makes it easier to remember and retrieve the stored information.

Cases of Hyperthymesia

Hyperthymesia is rare as there have been just a handful of cases that have been identified so far. One such case is that of Brad Williams who also goes by the name of Human Google, thanks to his superior memory.
Just name the date in his lifetime and within a few minutes, Brad can recall the sequence of events that took place on that day. Brad, who is nearing 60, can easily recollect what all things he did as well as any global events that occurred on any particular date.