How the human brain represents time and space is essential to understand
the conscious mind. When moving, mapping the environment yields a
topological relationship between the traveled distance and the order of
events. Nonetheless, in the absence of movement, e.g. while thinking about
future plans, the ordering of mental events may dissociate from their
spatial dimension.
In this M/EEG neuroimaging study, participants imagined themselves at
different times and places (self-projection) and ordered memorized
historical events from their mental standpoint. Early parametric changes of
evoked responses amplitude, localized in medial temporal region, reflected
past-to-future events succession while late spatial ordering evoked
components were localized in parietal and frontal cortices.
Overall, we report dedicated cortical signatures for the representation of
conscious spatial and temporal distance and ordinality in the human brain.
Crucially, the directionality of the psychological time arrow relies on
neural mechanisms that are fundamentally dissociable from spatial
directionalities.