Specific neural signatures in the human brain that are associated with remembering the location of a past event versus the timing of these events are reported in a study published online this week in Nature Neuroscience.
When a person remembers events from his/her past, the memory trace includes information about when and where the episode has occurred. Arne Ekstrom and colleagues used intracranial recordings to measure the neural activity in patients undergoing clinical monitoring while the subjects performed a memory retrieval task. They found that the frequency of naturally occurring brain rhythms are coupled differently when a person remembers the location rather than the relative timing of the past event. They also found that there is a central hub of activity in the parahippocampal gyrus area of the brain for both memory components, whereas the recollection of space versus time during memory retrieval is associated with differential activation of the parietal and prefrontal cortices.
This study provides new insights into the way the human brain can retrieve specific information from a memory trace.