Long-Term Memory In Psychology | Psychology for UPSC Optional (Notes) PDF Download

Introduction

Long-term memory (LTM) holds a crucial place in the multi-store memory model introduced by Atkinson and Shiffrin. It serves as the ultimate stage of memory processing, facilitating the lasting retention of information and skills. While the capacity of long-term memory is theoretically considered unlimited, the primary constraint on recall lies in accessibility rather than availability. The duration of long-term memory can vary from a few minutes to an entire lifetime. Encoding modes, primarily semantic (meaning) and visual (pictorial), are commonly utilized, although acoustic encoding can also occur. Comparatively, long-term memory can be likened to the information stored on a computer's hard drive, not readily available on the desktop (short-term memory), but accessible when needed, most of the time. This article delves into the various types of long-term memory, explicitly explicit and implicit memory, while highlighting the distinctions proposed by Tulving (1972).

Types of Long-Term Memory

Explicit Memory

Explicit memory, also known as declarative memory, encompasses conscious recollection and is further divided into two subtypes: episodic and semantic memory.

• Episodic Memory: Episodic memory stores information about personal experiences and events that individuals have encountered in their lives. It involves conscious thought and the ability to declare specific events. For instance, recalling one's first day at school falls under episodic memory.
• Semantic Memory: Semantic memory pertains to the explicit memory responsible for storing general knowledge and factual information about the world. This includes knowledge about word meanings, concepts, and general understanding. For instance, knowing that London is the capital of England exemplifies semantic memory. Semantic memory also relies on conscious thought and declarative recall.

Implicit Memory

Implicit memory, also referred to as non-declarative memory, deals with knowledge that is typically acquired unconsciously and does not require conscious thought. It involves knowing how to perform certain actions or skills. Implicit memory consists of procedural memory and is not accompanied by declarative recall.

• Procedural Memory: Procedural memory plays a vital role in implicit long-term memory by storing information related to motor skills and knowing how to perform various tasks. It operates without conscious awareness and remains non-declarative. For example, riding a bicycle relies on procedural memory.

Supporting Evidence and Distinctions:

Cohen and Squire (1980) made a significant distinction between declarative knowledge and procedural knowledge. Procedural knowledge pertains to the skills and abilities individuals possess, such as playing an instrument or tying shoelaces. It does not require conscious thought and is often executed automatically. Declarative knowledge, on the other hand, involves conscious recollection and focuses on factual information. Patients with amnesia have provided insights into this distinction. While their ability to retain declarative information is impaired, their procedural memory remains largely unaffected. They can still recall previously learned skills and acquire new ones.

Exploring Long-Term Memory Capacity and Duration:

• The concept of very long-term memory (VLTM) has been investigated by Bahrick, Bahrick, and Wittinger (1975). In their study, they examined the memory retention of nearly 400 participants aged 17 to 74. The participants were asked to recall the names of their graduating class members, enabling researchers to assess memory accuracy over extended periods.
• The findings indicated that participants tested within 15 years of graduation achieved approximately 90% accuracy in identifying names and faces. Even after 48 years, accuracy remained relatively high, at 80% for verbal recall and 70% for visual recognition. Notably, participants demonstrated superior performance in photo recognition compared to free recall, suggesting that cues such as images aid memory retrieval. However, free recall presented more challenges, with accuracy declining to 60% after 15 years and 30% after 48 years.
• Based on these results, Bahrick et al. concluded that long-term memory possesses the potential for unlimited duration. It is worth noting that the study employed meaningful stimuli, utilizing high school yearbooks, thereby enhancing its external validity compared to studies employing meaningless images. However, confounding variables, such as potential rehearsal of memories over the years, were not explicitly controlled, highlighting the need for caution when applying the study's findings to real-world situations.

Conclusion

Understanding long-term memory is essential in comprehending the complex nature of human cognition. Long-term memory encompasses explicit and implicit memory, each playing a distinct role in retaining personal experiences, factual knowledge, and motor skills. While explicit memory relies on conscious recall, implicit memory operates without conscious thought. Long-term memory capacity is theoretically unlimited, with accessibility being the primary determinant of recall. Additionally, investigations into very long-term memory demonstrate the enduring nature of memory retention. Further research continues to unravel the intricacies of long-term memory, shedding light on how we store and retrieve information in our cognitive processes.