Serial position effect: The serial position effect refers to the tendency for people to have better recall for items at the beginning and end of a list, compared to those in the middle.
Chunking: Chunking is a memory strategy where individual pieces of information are grouped together into meaningful units. For example, remembering '1234567890' as '12 34 56 78 90'.
Primacy effect and recency effect: The primacy effect refers to better recall for items at the beginning of a list, while the recency effect refers to better recall for items at the end of a list. Both effects contribute to why middle items are often forgotten.