4: Memory
- Page ID
- 54077
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\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)memory refers to the mental processes involved in encoding, storing, and retrieving information. It is often conceptualized in terms of three main stages: (1) Encoding: This is the process of converting sensory input into a form that can be stored in memory. It involves attention, perception, and sometimes rehearsal, which helps transfer information from short-term to long-term memory. (2) Storage: Once information is encoded, it must be stored for later use. (3) Retrieval: This is the process of accessing and bringing stored information back into conscious awareness when needed. Retrieval can be affected by various factors such as context, mood, and the way information was encoded.
- 4.1: Memory and the Brain
- This page discusses the role of various brain structures in memory formation and consolidation. The hippocampus is crucial for forming new memories and converting them from short- to long-term, but not essential for retention post-consolidation. The amygdala modulates the strength of memory consolidation, particularly for emotional events, while the cerebellum is important for procedural memory, affecting skills and motor learning.
- 4.2: Memory Processes
- The page discusses the physical characteristics and storage of memory in the brain, noting that specific brain regions, such as the temporal, occipital, and frontal lobes, play key roles in different types of memory, like sensory, short-term, and long-term memory. Memory traces, or engrams, involve neural changes associated with memory storage, aided by neuroplasticity. The hippocampus helps consolidate memories but doesn't store them.
- 4.3: Encoding
- Memory encoding is the process by which information is transformed into a construct that can be stored in the brain and recalled from short- or long-term memory. This process begins with perception, leading to the synthesis of experiences in the brain's thalamus and analysis by the hippocampus to decide on long-term storage. Encoding is selective, emphasizing distinctiveness and emotional impact, such as flashbulb memories, which may be vivid though not always accurate.
- 4.4: Storage
- Memory storage involves encoding experiences into short-term or long-term storage, where the latter optimizes space, similar to digital compression. Short-term memory holds information briefly, with limited capacity suggested by Miller to be around seven items, while long-term memory, potentially unlimited, stores information longer through rehearsal and processing. Memories are not exact replicas but reconstructions influenced by current beliefs.
- 4.5: Retrieval
- Memory retrieval involves recalling information from long-term memory, with key types being recall and recognition. Recall can occur through serial, free, and cued recall, with effects like the primacy and recency influencing it. Retrieval may be hindered by proactive and retroactive interference, where old and new information affect memory. Retrieval failure, such as the tip-of-the-tongue phenomenon, occurs when specific memory retrieval is challenging despite partial recall or related cues.
- 4.6: Modal Model of Memory
- This page discusses the three major classifications of memory: sensory, short-term, and long-term memory. Sensory memory briefly retains large amounts of information, encompassing iconic, echoic, and haptic types. Short-term memory processes information quickly and includes phenomena like the Stroop effect and Miller's "Magic Number" for memory span. Long-term memory stores information for extended periods, often using chunking techniques to enhance recall.
- 4.7: Ebbinghaus
- Hermann Ebbinghaus, a pioneer in memory research, made significant findings that can enhance memory retention. He discovered that memory decays rapidly at first before stabilizing, indicating the importance of reviewing material close to the time it is needed, such as before an exam. Ebbinghaus also identified the spacing effect, where learning is more effective when spread over time rather than crammed.
- 4.8: William James- isolating Short-term and Long-term memory
- During the 1960s, debates arose over whether human memory comprises a single or dual-component system. Arthur Melton argued for a unified system based on evidence of long-term memory (LTM) activation in short-term memory (STM) experiments. However, the concept of separate memory systems gained traction, notably with the 1968 Atkinson-Shiffrin model introducing the Multi-store model, which included sensory memory, STM, and LTM.
- 4.9: Serial Position Curve
- The serial position curve describes the tendency for people to better remember words presented at the beginning (primacy effect) and end (recency effect) of a list, while words in the middle are less well retained. This pattern is attributed to the effects of rehearsal on memory: early words benefit from being rehearsed and transferred to long-term memory, while later words are easily recalled from short-term memory due to their immediate rehearsal before testing.
- 4.10: Recency Effects and Primary Effects
- Serial recall is a memory process where individuals remember items or events in the order they occurred. It uses past memories to cue subsequent items within a sequence. In memory tasks, two key effects are often observed: the primacy effect, where initial list items are recalled more easily due to extra rehearsal, and the recency effect, where recent list items are recalled readily since they remain in short-term memory. These effects illustrate how memory recall varies with order and recency.
- 4.11: Short Term Memory
- Short-term memory (STM), or working memory, is a temporary storage system for processing sensory information and connecting it to long-term memory. Its capacity lasts about 20 seconds, with most people able to retain approximately 7 items, according to George Miller's 1956 research, which cited a capacity of 7 plus or minus 2 items. STM is likened to information on a computer screen, with memory consolidation involving the rehearsal of information to transfer it to long-term memory.