Why dementia sufferers have memory problems
Washington: A new research from the University of Cambridge has revealed that memory difficulties such as those seen in dementia may arise because the brain forms incomplete memories that are more easily confused.
Researchers found that the ability of the brain to maintain complete, detailed memories is disrupted. The remaining, less detailed memories are relatively easily confused, leading to an increased likelihood of falsely remembering information that was not encountered.
The researchers hope that their research could lead to new treatments that reduce the confusion between memories, perhaps with the development of drugs that can enhance the complex, detailed representations that are required to separate memories.
"This study suggests that a major component of memory problems may actually be confusion between memories, rather than loss of memories per se,” said Dr Lisa Saksida.
"This is consistent with reports of memory distortions in dementia - for example, patients may not switch off the cooker, or may fail to take their medication, not because they have forgotten that they should do these things, but because they think they have already done so," she added.
Animals were allowed to look at an object and then, after an hour, were given a memory test in which they were either shown the same object again, or a new object.
Normal animals spent more time exploring the new object, indicating that they remembered the old object but amnesic animals, however, performed poorly on the memory task, as they spent an equal amount of time exploring the old and the new object.
Interestingly, the amnesic animals explored the new object less than the normal animals did, indicating false memory for the new object.
Saksida continued, "One thing that we found very surprising about our results was the extent of the memory recovery, achieved simply by reducing the incoming information prior to the memory test.
"Not only does this result confound our expectations, but it also gives us a clearer understanding of the possible nature of the memory impairment underlying amnesia and certain types of dementia, which is critical to developing more sophisticated and effective treatments."
"Early detection of memory impairment is critical for the development of such treatments, and a better understanding of the nature of the impairment, as we have found here, is critical to such early detection."
The findings are published today in the journal Science.