Final answer:
The "decay" theory of forgetting suggests that memories can fade over time if not used; this is supported by evidence showing rapid loss of memory in certain conditions and influenced by interference. Encoding failure indicates that memory loss can also occur if details are never properly stored.
Step-by-step explanation:
In the context of psychology, the "decay" theory of forgetting posits that memories can fade or decay over time due to lack of use. In one illustrative case, a student's mother struggles to remember the details of 'To Kill a Mockingbird'; this example demonstrates storage decay, where unused information fades with time. Studies by researchers such as Peterson and Peterson showed a significant drop in the recall of trigrams after 18 seconds, suggesting that without rehearsal, short-term memory fades quickly. Other researchers have observed similar phenomena in long-term memory, where the initial memorization of information suffers from rapid forgetting, according to Ebbinghaus's forgetting curve.
Interference is another major component that affects memory retention, with proactive and retroactive interference playing a role in how well we can recall information. Encoding failure, a distinct concept from decay, explains our inability to remember details never fully processed and stored in memory, such as finer points on a penny. Despite these challenges, our long-term memory has a vast capacity for information storage, although organization and retrieval can be complex and are susceptible to various forms of forgetting.