Specifying the core network supporting episodic simulation and episodic memory by activation likelihood estimation.
Level 1 - systematic review of randomized trials
Meta-analysis of neuroimaging studies (graded by design analogy for non-clinical cognitive neuroscience).
PubMed 26142352 · doi:10.1016/j.neuropsychologia.2015.06.034
What was done
The authors conducted two Activation Likelihood Estimation (ALE) meta-analyses of functional neuroimaging studies. The first meta-analysis evaluated brain regions jointly engaged during both episodic memory recollection and episodic simulation of hypothetical events. The second meta-analysis tested for brain regions that showed consistently greater activation during episodic simulation compared to episodic memory.
What was found
The abstract reports no numerical values, effect sizes, or counts of included studies and participants. Qualitatively, joint engagement occurred across medial surface regions, medial temporal lobe structures (hippocampus and parahippocampal cortex), lateral temporal and inferior posterior parietal cortices, and bilateral dorsolateral prefrontal cortex, all overlapping with the default network. Furthermore, episodic simulation engaged left dorsolateral prefrontal cortex, posterior inferior parietal lobe, and broader fronto-parietal control and default network regions more strongly than episodic memory did.
Why it matters
This work delineates the shared core network underlying both remembering past events and imagining hypothetical ones, while identifying the additional cognitive control and default network resources uniquely recruited when constructing novel simulations.
Limits
The abstract does not disclose the number of studies, subjects, or foci included in the meta-analyses, nor does it report statistical thresholds or coordinates. Coordinate-based meta-analyses like ALE rely on published peak coordinates rather than raw image data, which can obscure subthreshold effects and within-study variance.
Cited by
- supports Reconstructing past memories and imagining the future activate a shared brain network and neural signature.