Types of Memory: Sensory, Short-Term, Long-Term, Iconic, Echoic

Print Friendly, PDF & Email

 

📘 7.1 Types of Memory: Sensory, Short-Term, Long-Term, Iconic, Echoic

Memory is the process of encoding, storing, and retrieving information. Different types of memory operate at various stages, serving specific cognitive functions.


🧠 1. Sensory Memory

Definition:
Sensory memory holds incoming sensory information for a very brief period (milliseconds to a few seconds), allowing initial processing before further encoding.

Key Features:

  • Duration: < 1–3 seconds
  • Capacity: Large but unprocessed
  • Modality-specific (iconic, echoic, haptic)

Purpose:
Acts as a buffer, giving the brain time to select relevant information for further processing.


📸 a) Iconic Memory (Visual)

  • Holds visual images for about 0.5 to 1 second.
  • Named by Ulric Neisser, based on the Greek word “eikon” (image).

Example:

  • When a flash of lightning appears, we briefly retain the visual impression.

🔊 b) Echoic Memory (Auditory)

  • Holds auditory input for about 3–4 seconds.
  • Helps in speech recognition and auditory tracking.

Example:

  • When someone says something and you ask “What?”—but then recall it a second later, that’s echoic memory at work.

🔄 2. Short-Term Memory (STM)

Definition:
STM temporarily stores and processes a limited amount of information for about 15 to 30 seconds unless rehearsed.

Key Features:

  • Capacity: 7 ± 2 items (Miller’s Law)
  • Duration: 15–30 seconds
  • Encoding: Acoustic or verbal

Example:

  • Remembering a phone number long enough to dial it.

Real-life use:

  • Holding an OTP received on mobile for typing into a form.

📦 3. Long-Term Memory (LTM)

Definition:
Stores information permanently for later retrieval; virtually unlimited capacity.

Key Types:

  • Explicit (Declarative): Facts & events (e.g., names, historical dates)
    • Episodic (personal experiences)
    • Semantic (general knowledge)
  • Implicit (Non-declarative): Skills, habits (e.g., riding a bicycle)

Example:

  • Remembering concepts learned in high school.
  • Procedural memory for typing without looking at the keyboard.

🔍 Comparison Table

Type of Memory Duration Capacity Encoding Example
Sensory <1 to 3 seconds Large Sense-based Seeing a light flash, hearing a tone
Iconic ~0.5 seconds Visual sensory Visual Flashing images
Echoic ~3–4 seconds Auditory Auditory Echoes of spoken words
Short-Term 15–30 seconds 5–9 items Mostly acoustic Recalling a number
Long-Term Years/lifetime Unlimited Semantic/Visual Remembering how to ride a bike

🏛️ Application in Governance & Education

  • E-learning:
    • STM and LTM distinctions help in designing chunked content for better retention (e.g., Mission Karmayogi training modules).
  • Exam Preparation:
    • Effective UPSC strategies often involve transferring STM (cram memory) to LTM (conceptual understanding) through revision and retrieval practice.
  • Policy Communication:
    • Public campaigns should repeat messages across multiple sensory channels (visual + audio) to optimize sensory and short-term memory for action triggers (e.g., COVID safety jingles).

🧠 Real-World Examples

Situation Type of Memory Used
Remembering an OTP briefly Short-Term Memory
Recognising a road sign instantly Iconic (Sensory) Memory
Understanding spoken instructions Echoic Memory
Recalling your UPSC roll number Long-Term Semantic Memory
Recalling the sound of a jingle Long-Term (Implicit) Memory

✍️ Answer Writing Tips

  • Start with a clear definition of memory and introduce the classification.
  • Explain each memory type in a structured format (definition, duration, encoding, example).
  • Use Indian governance or education-related examples to show relevance.
  • End with a comparison table or flowchart if space allows.

 

You may also like...

error: Content is protected !!