A recent neuroscience review questions the long-held belief that memories are unchanging records of past events, finding that each time we remember something, the brain reconstructs the memory by blending details from the original event with the current situation.
Published in Neuroscience & Biobehavioral Reviews, this research helps explain why memories can shift, become less accurate, or fade over time.
Researchers from the University of East Anglia and the University of Texas at Dallas reviewed nearly 200 journals from psychology, neuroscience, philosophy, and animal research to develop a framework for episodic memory. They aimed to clarify what qualifies as a memory, how the brain stores it, and why remembering can alter it.
Memories Aren’t Stored Like Files
People often think of episodic memory as a mental archive. However, the researchers argue that this comparison does not accurately reflect how memory works in the brain. “Memories aren’t just stored like files in a computer,” said lead researcher Prof. Louis Renoult of UEA’s School of Psychology.
The study finds that a memory consists of several components. Some parts are easily accessible, while others remain inactive until triggered by a cue, such as a familiar smell, a place, or a question.
The researchers emphasize that a memory must be linked to a real past event to be considered an actual memory. Even so, what we remember is rarely an exact copy of the original experience. “It can include extra details from our general knowledge, past experiences, or even the situation we’re in when we remember it,” Renoult said.
The review highlights a process known as re-encoding, where older memories are updated each time they are recalled. The team suggests that this ongoing updating process helps explain why memories can become distorted, confused, or less clear. “This work helps us understand why our memories aren’t always reliable and how they can be influenced by time, context, and even our own imaginations,” Renoult said.
Storing Inactive Memories
A large part of the study examines the hippocampus, a brain structure essential for forming and organizing memories. The researchers propose that memory traces can remain inactive and unconscious until activated by an environmental cue.
“These conscious representations of our past are typically a combination of retrieved information of the original experience, generic knowledge about the world, and information relevant for the current situation,” Renoult said.
This combination explains why episodic memory is both powerful and fragile. The brain can store complex experiences in flexible ways, but this flexibility also makes memories vulnerable to change.
A New Integrated Framework
Renoult and his team reviewed nearly 200 studies, covering human brain imaging, neuropsychology cases, animal models, and philosophical analysis.
“We wanted to suggest a new way of looking at things by combining ideas from different fields,” he said. “The goal was to make sense of problems that haven’t been solved yet and spark fresh research.”
Bringing together this range of studies allowed the researchers to better define memory representations and how the brain changes them.
Why Memory Matters
“Understanding how memories are formed, stored, and reshaped over time is crucial because memory underpins so much of our daily lives—from learning and mental health to decisions made in courtrooms,” Renoult said.
The study concludes that true memories come from real experiences but also change each time we recall them. This finding adds to ongoing discussions about the accuracy and reliability of memories in professional settings.
“By revealing that memories are dynamic rather than fixed, this research helps us better understand why they can change and how that impacts the way we think, feel, and act,” he added.
Austin Burgess is a writer and researcher with a background in sales, marketing, and data analytics. He holds a Master of Business Administration and a Bachelor of Science in Business Administration, as well as a certification in Data Analytics. His work combines analytical training with a focus on emerging science, aerospace, and astronomical research.