Understanding Memory: Encoding, Storage, and Retrieval
### Recalling and Coding The process of changing data into a format that can be stored in memory is known as "encoding." It entails transforming sensory input into a mental model that the brain can store and retrieve later. Semantic, acoustic, or visual encoding are all possible. ### Types of Memory 1. Unless rehearsed, **Short-term Memory (STM):** holds information for a short period of time, typically between 20 and 30 seconds. STM typically has a capacity of around 72 items. 2. Long-term memory, or LTM, stores information for a considerable amount of time—possibly a lifetime. It contains both explicit (conscious) and implicit (unconscious) memories and appears to have an unlimited capacity. 3. A brief storage system that stores information from the senses for a few seconds is referred to as sensory memory. It acts as a buffer for the senses to absorb stimuli. - **Iconic Memory:** A type of sensory memory that stores visual information for roughly one and a half seconds. - **Echoic Memory:** A kind of sensory memory that stores auditory information for between two and four seconds. The Multi Store Method Atkinson and Shiffrin' s "Multi Store Model" of memory suggests that there are three stores of memory: sensory memory, short-term memory, and long-term memory. In a straight line, information moves through these stores. The key to transferring information from STM to LTM is rehearsal. ### Processing Levels Craik and Lockhart's Levels of Processing model posits that memory retention is influenced by processing depth. Long-term retention is better with semantic processing than with surface-level processing. ### Methods of Organization and Memorization The process of organizing data in a manner that makes it simpler to recall, such as by categorizing or chunking it, is known as "organization." Mnemonic techniques are methods for improving memory. Some common methods include: - **Acronyms:** Forming a word from the first letters of a list of things. - "Visualization" refers to the process of forming vivid mental images of information. - "Method of Loci": Associating information with particular locations in a place that is already familiar. ### Hypotheses About Forgetting 1. The "Decay Theory" posits that memories deteriorate over time as a result of time, particularly if they are not accessed frequently. 2. The interference theory proposes that additional information hinders memory retrieval. It contains: - "Proactive Interference": Old memories prevent new information from being retrieved. - "Retroactive Interference": New information prevents older memories from being retrieved. 3. **Retrieval Failure:** This occurs when there are insufficient retrieval cues and information that is stored in memory cannot be accessed. Metamemory ### A person's awareness and comprehension of their own memory processes is referred to as "metamemory." Memory strategies and retrieval can be monitored and controlled as part of this ability. ### Dementia 1. **Anterograde Amnesia:** A brain injury that prevents people from making new memories. Anterograde amnesia sufferers are able to recall past events, but they struggle to recall new information. 2. **Retrograde Amnesia:** Memory loss that occurred prior to a brain injury. Retrograde amnesia patients may lose access to their past memories while still being able to form new memories. These notes give a quick overview of important ideas about memory, such as how memories are encoded, stored, and retrieved, methods for improving memory, and theories about forgetting.
