Infant Memory Loss May Now Have Cause


A new study might have found the cause as to why people have infant memory loss. Most people do not remember much or anything past their third or fourth birthday, but scientists were never really sure why. There were a multitude of theories as to why people lacked infant recollection such as memories being rooted in language. Children usually start forming memories around the time they begin talking. However, the problem with this theory was that even most animals show infantile amnesia. The stage of language development could not explain the reason for childhood memory loss.

Sigmund Freud was one of the very first to write about infantile memory loss. He believed infantile amnesia was due to repression, purposeful forgetting of childhood memories because of their psycho-sexual content. Others believe that the main reason for infantile memory loss is simply because there has to be a sense of being before one can begin to recall memories from earlier in life.

Children usually fail to recall specified events until anywhere between the ages of two and four. Scientists have now come to the conclusion that this could possibly be due to the time when the developing brain starts to connect pieces of information. They found that the baby’s brain is developing so quickly that the newer memories essentially begin to erase the older ones.

The study suggested that the new generation of neurons might play a vital role in the cause of infant memory loss, which is not just limited to the human species. As people age, the new neuron production in the brain begins to decrease. During the study,the research group generated and used small electric shocks to help train lab mice to become fearful of a certain environment. The adult mice were fearful of the specified environment still 28 days later.

The young mice were a lot more forgetful than the older ones, as they would lose the recollection of the electric shock only a day after. The researchers then let some of the mice from the adult group use running wheels. According to scientists, running is linked to higher levels of developing brain cells. When they examined the mice once again, they found that the mice that had used the running wheel had forgotten their fear of the environment that they were trained to be afraid of. The other mice however, had not forgotten their fear and recalled the electric shocks when placed in the environment once again.

After, the researchers gave drugs to the infant mice to extend their memory by slowing down the rate of new neuron development, which is typically higher than their adult counterparts. They found that the treated mice were able to recall memories a lot better than the untreated, infant mice. According to the study, in order to understand memory better, new neuron production in the hippocampus part of the brain seems to be the best place to start. However, there could be other possible explanations for infant memory loss, such as an alteration in the connectivity between different areas of the brain.

Most people who currently have or have had young children can attest to the fact that the child’s brain is like a sponge, soaking up information and learning more everyday. The reason people can not seem to recall memories from this time in life might be because of all of the important information they were learning and storing as their brain generated new neurons. Although scientists have not yet found a way to bring back memories as an infant, they now know what could very well be the main cause of the loss in the first place.

By Addi Simmons

National Institute of Mental Health
The Telegraph
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