Memory Notes

Memory Notes

Chapter Overview

  • Author: Akshaya Periasamy, Assistant Professor, Department of Psychology
  • Year: 2020

Definition of Memory

  • Memory: The process by which people encode, store, and retrieve information.

Basic Processes of Memory

  1. Encoding:
    • The process by which information is initially recorded in a usable form for memory.
  2. Storage:
    • The maintenance of saved information within the memory system.
  3. Retrieval:
    • The process of recovering stored information and bringing it into awareness for use.

Systems of Memory Storehouse

  1. Atkinson & Shiffrin (1986) – Information Processing Model
    • Sensory Memory: Briefly holds information recorded by the sensory systems.
    • Short-Term Memory: Holds information for approximately 15-25 seconds.
    • Long-Term Memory: Information can be retained permanently, depending on rehearsal.

Sensory Memory

  • Definition: Initial momentary storage of information lasting only an instant.
  • Characteristics:
    • Recorded as raw, non-meaningful stimuli.
    • Most information is lost unless attended to, leading to further processing in short-term memory.
  • Types of Sensory Memory:
    • Iconic Memory: Visual information lasting about 1 second.
    • Echoic Memory: Auditory information lasting 5-10 seconds.

Sperling Experiment (1960)

  • Conducted by George Sperling to understand sensory memory.
  • Method: Brief exposure of a series of letters.
  • Findings:
    • Most people could recall 4-5 letters after a brief presentation.
    • Introduction of tones after exposure indicated that the full array was stored in sensory memory, with recall accuracy dependent on time delay between exposure and tone.

Short-Term Memory

  • Holds information for 15-25 seconds.
  • Limited storage capacity (~7 ± 2 items).
  • To enhance short-term memory:
    1. Chunking: Grouping stimuli into meaningful units.
    2. Rehearsal: Active repetition of information.
  1. Mnemonics: Techniques for organizing material to improve retention.

Long-Term Memory

  • Characterized as relatively permanent with unlimited storage capacity.
  • Divided into modules:
    • Declarative Memory: Factual information (e.g., names, dates).
    • Procedural Memory: Skills and habits (e.g., riding a bike).
    • Semantic Memory: General knowledge about the world.
    • Episodic Memory: Biographical details and personal experiences.

Retrieval and Reconstruction

  • Retrieval Cues: Stimuli that help in recalling information (e.g., words, emotions).
  • Context and State Dependent Memories:
    • Context Dependent Memory: Easier recall in similar environments.
    • State Dependent Memory: Recall influenced by the individual's physiological and psychological state.
  • Tip-of-the-Tongue Phenomenon: Difficulty retrieving known information.
  • Flashbulb Memory: Highly detailed memories of important events.

Levels of Processing Theory (Craik and Lockhart, 1972)

  • Deeper processing leads to better memory retention.
  • Types of processing:
    1. Structural Level: Shallow, sensory features.
    2. Phonetic Level: Intermediate, labeling and categorizing.
    3. Semantic Level: Deepest, meaning and context relationships.

Forgetting

  • Defined as loss of encoded information.
  • Key theories:
    1. Encoding Failure: Lack of attention leads to no encoding.
    2. Decay Theory: Information fades over time due to nonuse.
  1. Interference Theory: Old or new information disrupts recall.
  2. Motivated Forgetting/Repression: Difficulty recalling anxiety-provoking information.

Memory Dysfunctions

  1. Alzheimer's Disease: Progressive memory loss; initially starts as forgetfulness.
  2. Amnesia:
    • Retrograde: Loss of memory of past events.
    • Anterograde: Inability to form new memories after an event.
  3. Korsakoff's Syndrome: Memory loss associated with chronic alcoholism and nutrient deficiencies.

Biological Bases of Memory

  • Long-Term Potentiation: Increased neuron sensitivity with repeated stimulation.
  • Specialization in brain areas for different types of memory.