Answer:
transience.
Step-by-step explanation:
Transience: In psychology, the term "transience" is described as the decreased capability of an individual to access or retrieve memories as time goes by or over time. Transience is considered as one of the seven different signs of memory that generally occurs with an individual's "aging process" yet it can also occur in a completely severe way as a consequence of his or her brain damage. It arises or affects both long-term and short-term memories.
In the question above, the given phenomenon best illustrates transience.