Read an Academic Passage

The Structure and Function of Human Memory

Human memory is a complex cognitive process responsible for encoding, storing, and retrieving information. It is not a single, monolithic entity but rather a system composed of different components, each with distinct characteristics. The most widely accepted model divides memory into three main stages: sensory memory, short-term memory, and long-term memory. This multi-store model provides a framework for understanding how information flows through the mind, from a fleeting sensory impression to a potentially permanent record of an event or fact.

The process begins with sensory memory, which holds information from the senses for a very brief period, typically less than a second. If attention is paid to this information, it moves into short-term memory, also known as working memory. This stage has a limited capacity, generally holding about seven items for around 20 to 30 seconds. Rehearsal, or the conscious repetition of information, is a common strategy used to keep information in short-term memory and facilitate its transfer to the next stage. Without such effort, the information is quickly discarded.

Long-term memory is the final stage, representing the vast and relatively permanent storage of information. It is divided into two major types: explicit (or declarative) memory and implicit (or procedural) memory. Explicit memory involves the conscious recall of facts and events, such as remembering a historical date or a personal experience. Implicit memory, on the other hand, is unconscious and involves skills and routines, like riding a bicycle or typing on a keyboard. Information is organized and stored in long-term memory through complex neural networks, allowing for retrieval when needed.