Neuroscientists were keen to know how and when memory forms. Now, Yale scientists have come up with a possible explanation.
By identifying brain activity in the hippocampus of newborn rats, scientists identified three distinct stages in brain development that occur before episodic memories can form. They found- at the beginning of the third week of postnatal life, there was no evidence of neural activity that would allow the animal to link sequential events either in time or space.
Scientists also identified changes in brain architecture later in the third week of rodent life that would allow the brain to encode distinct experiences using innate patterns of neuronal activity. However, no evidence of lasting changes in these neural patterns was found from those experiences.
George Dragoi, assistant professor of psychiatry and neuroscience, said, “They are constantly in the present. This stage corresponds to the human state of infantile amnesia — or the inability to properly encode and store episodic memories of events in infancy and early development so that they can be recalled in adulthood.”
“Early in the fourth week of postnatal life, the rat brains showed beginnings of network activity that would allow them to record the singularity of experience in space and time for long-term.”
The findings were reported Jan. 10 in the journal Science.