Hyperthymesia
Hyperthymesia, also known as piking or hyperthymestic syndrome, is an unique neurological condition, in which people have a superior autobiographical memory, meaning they can remember every single event that has happened in their lives. It seems that people with this condition tend to spend a lot of time thinking about their personal past, are not able to focus for long periods of time, and often disconnect themselves from the outside world.
The term “hyperthymesia" is derived from the Greek words thymesis meaning "remembering," and hyper meaning "excessive".
This condition it’s different from other forms of exceptional memory (like savant syndrome or autism), because hyperthymestic individuals tend to have personal memories which are encoded involuntarily and retrieved automatically, and obsess over details, which is why in different studies made, the region of the brain associated with Obsessive-Compulsive Disorder (OCD), was larger than normal. Also, hyperthymestic reminiscence are restricted to a person’s lifetime and it is believed to be a subconscious process.