Affiliations: Physiological Psychology, University of Bielefeld,
D-33501 Bielefeld, Germany | Clinic of Neurology, University of Cologne, Cologne,
Germany | Max-Planck-Institute for Neurological Research,
Cologne, Germany
Abstract: What distinguishes the recall of real-life experiences from that of
self-created, fictitious emotionally laden information? Both kinds of
information belong to the episodic memory system. Autobiographic memories
constitute that part of the episodic memory system that is composed of
significant life episodes, primarily of the distant past. Functional imaging
was used to study the neural networks engaged in retrieving autobiographic and
fictitious information of closely similar content. The principally activated
brain regions overlapped considerably and constituted temporal and inferior
prefrontal regions plus the cerebellum. Selective activations of the right
amygdala and the right ventral prefrontal cortex (at the level of the uncinate
fascicle interconnnecting prefrontal and temporopolar areas) were found when
subtracting fictitious from autobiographic retrieval. Furthermore, distinct
foci in the left temporal lobe were engaged. These data demonstrate that
autobiographic memory retrieval uses (at least in non-brain damaged
individuals) a network of right hemispheric ventral prefrontal and temporopolar
regions and left hemispheric lateral temporal regions. It is concluded that it
is the experiential character, its special emotional infiltration and its
arousal which distinguishes memory of real-life from that of fictitious
episodes. Consequently, our results point to the engagement of a bi-hemispheric
network in which the right temporo-prefrontal hemisphere is likely to be
responsible for the affective/arousal side of information retrieval and the
left-hemispheric temporal gyrus for its engram-like representation. Portions of
the neural activation found during retrieval might, however, reflect
re-encoding processes as well.
