What does the term "STM capacity" refer to in psychological studies?

• A. 7 +/- 2
• B. Limitless
• C. 40 people
• D. Encoding

Answer: (A)

The term "STM capacity" refers specifically to the range of information that can be held in short-term memory, which is famously encapsulated by the research of George A. Miller. His work indicates that the capacity of short-term memory typically ranges around seven items, give or take two. This principle, known as "Miller's Law," suggests that on average, people can only hold approximately 5 to 9 pieces of information simultaneously in their short-term memory.

This understanding is crucial in the study of cognitive psychology and memory, as it highlights the limitations of human memory capacity. The other choices do not accurately reflect the recognized constraints of short-term memory: suggesting that memory capacity is limitless overlooks the inherent cognitive limitations, while referencing a specific number of people or "encoding" does not relate directly to the general concept of short-term memory capacity.