New research shows memory is a dynamic and interactive process

May 28, 2014

Research presented by Morris Moscovitch, from the Rotman Research Institute at the University of Toronto, shows that memory is more dynamic and changeable than previously thought. Dr. Moscovich's results reveal that important interactions between the hippocampus and the neocortex, two regions of the brain, have different yet complementary roles in remembering places and events. These results highlight that different forms of memories exist in the brain, and that these are encoded in different, but interacting parts of the brain. Dr. Moscovitch proposes a novel theory to explain these interactions, that furthers our understanding of what we remember, and could be useful for treatment and management of people with memory disorders.

These results were presented at the 8th Annual Meeting of the Canadian Association for Neuroscience held in Montreal, Canada May 25 to 28th 2014.

By studying how humans remember events and places in the short and long term, and how rodents remember and navigate through familiar and unfamiliar environment, Dr. Moscovitch and others have revealed differences between what they call "", which is a form of memory rich in contextual details, dependent on a brain region called the , and another form of memory, called "" which relies primarily on neocortex, and which is a more general memory, recording the gist of the initial episodic memory.

Studies in animals and humans have shown that the hippocampus, a brain region located deep inside the brain, has a central role in recent and remote episodic memory. Patients with hippocampal loss, including the famous Henry Molaison (patient HM) and Kent Cochrane (patient KC), were shown to be unable to make new memories, but they retained the ability to recall earlier events, in a schematic, general fashion. Dr. Moscovitch, investigating how rich, recent memories are often converted to more schematic, remote memories has elaborated a theory he has termed "multiple trace/transformation theory".

According to multiple trace/transformation theory, each time an episodic memory is retrieved, it is automatically re-encoded by the hippocampus along with the new context in which retrieval occurs. Over time, and with every retrieval, multiple memory traces accumulate; the neocortex extracts similarities from these traces to form a generalized memory, the semantic memory. By this process, the memory is transformed over time, from a mostly hippocampus dependent, context-rich memory, to a more general memory, a recording of the essential elements of the memory, that captures the gist of the initial episodic memory.

Dr. Moscovitch presented results that show that the same processes apply to memory about places and the environment. Initially dependent on the hippocampus, they also are transformed, and become schematic memories that can be retrieved without the involvement of the hippocampus. As it was previously thought that the hippocampus was always involved in remembering places, this discovery sheds new light on the different forms of memory that exist.

"Spatial representations provide the framework in which events unfold, so that they interact with each other to form rich episodic memories that have both spatial and event elements" says Dr. Moscovitch. "Memory for events is facilitated if they occur in familiar rather than unfamiliar places. These findings could be used to help ameliorate problems in older adults, and in people with dementia, who have to leave their home and move into new living quarters."

Explore further: When you can recite a poem but not remember who asked you to learn it a few days earlier

More information: www.can-acn.org/meeting2014

Related Stories

Why bigger is better when it comes to our brain and memory

December 21, 2011

The hippocampus is an important brain structure for recollection memory, the type of memory we use for detailed reliving of past events. Now, new research published by Cell Press in the December 22 issue of the journal Neuron ...

Outside the body our memories fail us

March 10, 2014

New research from Karolinska Institutet and Umeå University demonstrates for the first time that there is a close relationship between body perception and the ability to remember. For us to be able to store new memories ...

What happened when? How the brain stores memories by time

March 12, 2014

(Medical Xpress)—Before I left the house this morning, I let the cat out and started the dishwasher. Or was that yesterday? Very often, our memories must distinguish not just what happened and where, but when an event occurred—and ...

Recommended for you

New mechanism discovered behind infant epilepsy

September 3, 2015

Scientists at Karolinska Institutet and Karolinska University Hospital in Sweden have discovered a new explanation for severe early infant epilepsy. Mutations in the gene encoding the protein KCC2 can cause the disease, hereby ...

Neuron responsible for alcoholism found

September 2, 2015

Scientists have pinpointed a population of neurons in the brain that influences whether one drink leads to two, which could ultimately lead to a cure for alcoholism and other addictions.

Scientists see motor neurons 'walking' in real time

September 2, 2015

When you're taking a walk around the block, your body is mostly on autopilot—you don't have to consciously think about alternating which leg you step with or which muscles it takes to lift a foot and put it back down. That's ...

Deciphering the olfactory receptor code

August 31, 2015

In animals, numerous behaviors are governed by the olfactory perception of their surrounding world. Whether originating in the nose of a mammal or the antennas of an insect, perception results from the combined activation ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

russell_russell
not rated yet May 29, 2014
http://medicalxpr...ain.html
The foundation of all memory and learning.

Any retrievable memory with an act of recall invokes further damage to the area where any memory is stored.

"...it is automatically re-encoded by the hippocampus along with the new context in which retrieval occurs."

No. Retrieval invokes more damage and repair to the storage cells not preciously affected and morphing the memory. Retrieval rate strengthens existing pathways and creates new pathways to the cells call upon to express the stored gene expressions of the event stored. The hippocampus is transmitter and receiver. A transmitter and receiver need to be sourced from a preexisting storage of memory or information.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.