Dr Michael Crossley, Senior Research Fellow in Neuroscience, used pond snails to study the factors impacting on memory interference.
He found that, when tasked with learning two similar things, snails were only able to store and recall the first memory.
Tasks - Snails - Information - Memories
Conversely, when faced with learning two totally unrelated tasks, the snails were able to retain all the information and successfully store both memories.
Dr Crossley said: "The brain of a snail is much simpler than ours but there are some key parallels which mean studying them can help us to understand more about our own abilities for learning and memory.
Events - Succession - Competition - Memories - People
"We know that multiple learning events occurring in quick succession can lead to competition between memories. This is why, when introduced to multiple people in one go, we can't usually remember every name.
"Up until now though, we weren't sure which factors were causing a memory to be remembered or forgotten."
Colleagues - Sussex - Neuroscience - Dr - Crossley
With colleagues from Sussex Neuroscience, Dr Crossley trained snails using food-reward and aversive conditioning .
Using brain recording, they realised that the same neuron was used when snails tried to learn two similar things. This prompted an overlapping mechanism, which caused only one memory (the first one) to survive, known as proactive interference.
Contrast - Tasks - Neurons - Competition - Overlap
In contrast, when two different tasks were learnt, two separate neurons were used, resulting in no competition, no overlap and the successful storing of both memories.
Dr Crossley explained: "We realised that there is an overlapping or non-overlapping mechanism which plays a key role in determining which memories survive.
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