Herman Ebbinghaus
Herman Ebbinghaus, born 1850, was the psychologist commonly referred to as the Father of Memory. He was the first person to use nonsense syllables to determine how association with words can affect how well a person memorizes a list of items. Ebbinghaus discovered that repeating the learning procedure (studying the list of nonsense syllables) each day enabled him to remember more and more of the list the next morning. He called this phenomenon the learning curve.
Once he had learned the entire list, Ebbinghaus decided to see how many days it took him to forget the entire list if he did not study. He discovered that he forgot syllables in the middle of the list more quickly than the first or most recent syllables. This he called the forgetting curve. This phenomenon of rembering the first items on his list became known as the primacy effect: things that are studied for longer periods of time stick around longer. The phenomenon of remembering the most recent items on his list became known as the recency effect: things that were freshest in his memory.