Caltech researchers have now determined that strong, stable memories are encoded with ‘teams’ of neurons all firing in synchrony, providing redundancy that enables these memories to last for a period. This research can help to understand how memory might be affected after brain damage, such as by strokes or Alzheimer’s disease.
Researchers developed a test to examine mice’s neural activity as they learn about and remember a new place. To study how memories, fade over time, researchers then withheld the mice from the track for up to 20 days. Upon returning to the track after this break, mice that had formed strong memories encoded by higher numbers of neurons remembered the task quickly. Even though some neurons showed different activity, the mouse’s memory of the track was clearly identifiable when analysing the activity of large groups of neurons. Hence, using neurons enables the brain to have redundancy and still recall memories even if some of the original neurons fall silent or are damaged.
Memory that is so fundamental to human behaviour that any impairment to memory can severely impact our daily life. Memory loss caused by diseases has devastating consequences that can interfere with the most basic routines like recognising relatives or remembering the way back home. This study thus suggest that memories might fade more rapidly as we age as a memory will then be encoded by fewer neurons. Should any of these neurons fail, the memory will then be lost. This study suggests that one day, designing treatments that could boost the recruitment of a higher number of neurons to encode the memory could help prevent memory loss.
The results match the saying that ‘the more you practice an action, the better chance that you will remember it later” – studies have supported with that the more you practice an action, the higher the number of neurons that are encoding the action. Results shows that increasing the number of neurons that encode the same memory enables the memory to last longer.
Source material from Science Daily