Types of Memory- Sensory Memory (Psy 301- Memory Lecture)

Types of Memory

  • Memory Categories: Three main types of memory exist: sensory memory, short-term memory, and long-term memory.

    • Sensory Memory: Brief retention of information; lasts for less than a second (milliseconds).

    • Short-Term Memory: Retains information for a longer duration, ranging from seconds to about one minute.

    • Long-Term Memory: The most substantial retention of information, which can last from hours and weeks to a lifetime.

Information Processing

  • Funnel Analogy:

    • Information enters sensory memory first; a small portion progresses to short-term memory, even fewer to long-term memory.

    • The processing of memory is selective with significant differences in the amount of information retained and the duration at each stage.

Demonstrations

  • Demonstration of Sensory Memory:

    • Initial Task: Participants view a brief display of letters arranged into three rows. The letters are shown for only a few milliseconds.

    • Recall Task: After the display disappears, participants write down as many letters as they remember.

    • Results:

      • Approximately 50% of participants remembered the first row of letters, fewer remembered the others.

  • Repetition of the Demonstration:

    • Variation: In this trial, participants were instructed to concentrate on only one row of letters indicated by spoken numbers (1, 2, or 3) after the display flashed off.

    • Outcomes: Increased recall for the indicated row suggests that any letters not recalled the first time were potentially processed in sensory memory but faded before attention could focus on them.

    • Results Analysis: Results showed an increase in recall accuracy for the indicated row compared to the first trial, indicating capacity for sensory memory retention.

Insights from the Demonstrations

  • Sensory Memory's Capacity:

    • Sensory memory can take in extensive information briefly.

    • The initial recall task illustrates the limitations of writing down letters; as one is being noted, others fade from memory.

  • Attention's Role:

    • The second demonstration highlights that attention greatly influences which information is transferred into short-term memory.

    • The retention of information in short-term memory is selective and dependent on what participants focus on during the recall process.