"The memory of a specific experience is stored in multiple parallel “copies.”
These copies are
---kept for varying lengths of time
---modified to some extent,
---and sometimes eventually deleted.
Professor Flavio Donato’s research group at the University’s Biozentrum found that memory development begins long before birth.
Professor Flavio Donato’s research group at the University’s Biozentrum found that memory development begins long before birth.
At least three different groups of neurons in the brain’s hippocampus emerge at different stages during embryonic development. A single event is stored in parallel memory copies in all three — in triplicate, if you like.
First to arrive during development, the early-born neurons are responsible for the long-term persistence of a memory. In fact,
even though their memory copy is initially too weak for the brain to access, it becomes stronger and stronger as time passes. Also in humans, the brain might have access to such memory only some time after its encoding.
In contrast, the memory copy of the same event created by the late-born neurons is very strong at the beginning but fades over time, so that if one waits long enough, such a copy becomes inaccessible to the brain.
First to arrive during development, the early-born neurons are responsible for the long-term persistence of a memory. In fact,
In contrast, the memory copy of the same event created by the late-born neurons is very strong at the beginning but fades over time, so that if one waits long enough, such a copy becomes inaccessible to the brain.
In the middle ground, among neurons emerging in between the two extremes during development, a more stable copy could be observed.
The hippocampus is the seahorse-shaped inner part of the brain that plays an important role in memory and learning. There are actually two hippocampi, one on each side, but they are generally referred to as a single unit. People who have lost one or both have great difficulty forming or retaining memories.
The researchers think that the type of neuron in which a memory is stored there might relate to how easy it is for memories to change. The memories stored short-term via late-born neurons can, they say, be modified and rewritten: “This means that remembering a situation shortly after it has happened primes the late-born neurons to become active and integrate present information within the original memory.”
The hippocampus is the seahorse-shaped inner part of the brain that plays an important role in memory and learning. There are actually two hippocampi, one on each side, but they are generally referred to as a single unit. People who have lost one or both have great difficulty forming or retaining memories.
The researchers think that the type of neuron in which a memory is stored there might relate to how easy it is for memories to change. The memories stored short-term via late-born neurons can, they say, be modified and rewritten: “This means that remembering a situation shortly after it has happened primes the late-born neurons to become active and integrate present information within the original memory.”
But when an event is remembered after much time has passed, the memory retrieved from the early-born neurons is hard to change.
Recalling an event soon after it occurs generally draws on those neurons that emerge late in development, which store the more malleable trace of the memory—which means that as we remember it, we can layer onto that memory trace associations with related events and ideas, and other new information.
Recalling an event soon after it occurs generally draws on those neurons that emerge late in development, which store the more malleable trace of the memory—which means that as we remember it, we can layer onto that memory trace associations with related events and ideas, and other new information.
For example, you may learn to associate your first memory of a room with more recent experiences in that room, such as of a bad smell or painful accident.
The different neuron populations allow us to preserve fundamental aspects of a memory over the long term, while also enabling us to adapt and incorporate new or related information we have learned about the world."
MindMatters