Model Answer
0 min readIntroduction
Short-term memory (STM), often referred to as working memory, is the cognitive system responsible for temporarily holding and manipulating information. The modal model of memory, proposed by Atkinson and Shiffrin in 1968, revolutionized the understanding of human memory by presenting a multi-store model. This model posits that information passes through three distinct stages: sensory memory, short-term memory, and long-term memory. Each store differs in capacity, duration, and the type of information it holds. This answer will describe the components of the modal model and critically evaluate its contributions and limitations in light of subsequent research.
The Modal Model of Short-Term Memory: A Description
The modal model, as initially proposed, outlines a linear flow of information. Let's examine each component:
1. Sensory Memory
This is the initial stage of memory, briefly holding a vast amount of sensory information (visual, auditory, etc.). It has a large capacity but a very short duration – typically milliseconds to a few seconds. Information is lost through decay if not attended to. Iconic memory (visual) lasts approximately 0.5 seconds, while echoic memory (auditory) lasts around 3-4 seconds.
2. Short-Term Memory (STM)
Information that receives attention from sensory memory moves into STM. STM has a limited capacity – famously estimated by George Miller (1956) as “7 ± 2” chunks of information. Duration is also limited, around 18-30 seconds without active maintenance through rehearsal. STM is considered an active workspace where information is manipulated and processed. Two types of rehearsal are important: maintenance rehearsal (repeating information to keep it active) and elaborative rehearsal (linking information to existing knowledge).
3. Long-Term Memory (LTM)
Information transferred from STM to LTM is stored relatively permanently. LTM has a theoretically unlimited capacity and duration. Transfer to LTM is facilitated by elaborative rehearsal and meaningful encoding. LTM is further divided into explicit (declarative) memory – conscious recall of facts and events – and implicit (non-declarative) memory – skills and habits.
Evaluation of the Modal Model
Strengths of the Model
- Conceptual Clarity: The model provided a clear and influential framework for understanding memory processes, stimulating a vast amount of subsequent research.
- Distinction between Stores: It highlighted the importance of differentiating between different memory stores based on their characteristics.
- Emphasis on Encoding: The model emphasized the role of encoding processes in transferring information from STM to LTM.
Weaknesses and Criticisms
- Oversimplification: The linear, unidirectional flow of information is an oversimplification. Memory processes are often more complex and interactive.
- The Case of Amnesia: Patients with amnesia often have intact STM but impaired LTM, suggesting that STM is not necessarily a gateway to LTM.
- Working Memory vs. STM: The model doesn't adequately account for the active manipulation of information, which is central to the concept of working memory, as proposed by Baddeley and Hitch (1974).
- Lack of Ecological Validity: The laboratory tasks used to study STM may not accurately reflect real-world memory processes.
- The Role of Attention: The model doesn’t fully explain the role of attention in selecting information for transfer to STM.
Alternative Models
Baddeley and Hitch’s (1974) working memory model proposed a more complex system with multiple components: the phonological loop, visuospatial sketchpad, central executive, and episodic buffer. This model emphasizes the active processing and manipulation of information, addressing a key limitation of the modal model. Further, the levels of processing theory (Craik & Lockhart, 1972) suggests that the depth of processing, rather than the store to which information is transferred, determines retention.
| Feature | Modal Model | Working Memory Model (Baddeley & Hitch) |
|---|---|---|
| Structure | Three sequential stores | Multiple components (phonological loop, visuospatial sketchpad, central executive, episodic buffer) |
| Emphasis | Storage | Active processing and manipulation |
| Information Flow | Linear, unidirectional | Interactive and dynamic |
Conclusion
The modal model of short-term memory was a landmark contribution to our understanding of human memory, providing a foundational framework for subsequent research. While its linear, sequential view has been challenged by more nuanced models like Baddeley and Hitch’s working memory model, it remains a valuable starting point for understanding the basic principles of memory storage and retrieval. Contemporary research continues to refine our understanding of the complexities of memory, emphasizing the interplay between different cognitive processes and the importance of individual differences.
Answer Length
This is a comprehensive model answer for learning purposes and may exceed the word limit. In the exam, always adhere to the prescribed word count.