Long-term memory (LTM) is memory that lasts from over 30 seconds to years. It differs from working memory or short-term memory, which stores items for only around 30 seconds. Biologically, short-term memory is a temporary potentiation of neural connections that can become long-term memory through the process of rehearsal and meaningful association.

As long-term memory is subject to fading in the natural forgetting process, several recalls/retrievals of memory may be needed for long-term memories to last for years, dependent also on the depth of processing. Individual retrievals can take place in increasing intervals in accordance with the principle of spaced repetition. This can happen quite naturally through reflection or deliberate recall, often dependent on the perceived importance of the material.

Sleep is considered an important factor in establishing well-organized long-term memories.

Related topics

• Long-term potentiation
• Contrast Short-term memory