Structures of Memory

Memory refers to the mental processes of encoding, storing and retrieving information.
Encoding is the process of putting sensory information into a form which can be used and stored in memory. This can be visual, acoustic, or semantic.
Storage is the process of holding onto that information over time.
Retrieval is the process of getting information out of memory storage in order to use it.
Memory can be divided into three main types: sensory memory, short-term memory, and long-term memory
Sensory memory is the shortest form of memory. It holds information from the senses for just a few seconds until it is processed further.
Short-term memory, also referred to as working memory, retains information for about 18-20 seconds but can hold only 5-9 items comfortably.
Long-term memory is a more permanent memory storage system with an essentially unlimited capacity.
Information in long-term memory can be further divided into declarative or explicit memory and non-declarative or implicit memory
Declarative memory refers to information that we can consciously remember and describe, such as facts and events. It is further divided into episodic and semantic memory.
Episodic memory stores information about personal experiences or specific events in time.
Semantic memory saves general knowledge or facts, such as the meanings of words or capital cities.
Non-declarative memory, also known as procedural memory, represents our memory for actions and skills that we can perform without conscious thought, such as riding a bike.
The model of memory proposed by Atkinson and Shiffrin, known as the Multi-Store Model, suggests that information flows between sensory memory, short-term memory, and long-term memory.
According to the Multi-Store Model, information must first pass through and be attended to in sensory memory before it can be encoded into short-term memory. If the information is rehearsed, it can then be transferred to long-term memory.
However, the Working Memory Model proposed by Baddeley and Hitch challenges the idea of a single short-term memory store. It suggests short-term memory consists of multiple components, including a central executive, visuospatial sketchpad, phonological loop, and episodic buffer.
The central executive oversees the whole system and coordinates the activities of the other ‘slave’ systems. The visuospatial sketchpad handles visual and spatial information. The phonological loop deals with spoken and written material and the episodic buffer is a temporary store that integrates information from the other components along with the sense of time.
Both the Multi-Store Model and Working Memory Model contribute to our understanding of the components and structure of memory.