Abstract
ABSTRACT
fMRI studies on the neuro-anatomical substrates of emotion in healthy subjects show various results. There are discrepancies in findings related to the processing of sadness. Is there one area in the brain responsible? - If so, is it also involved in other forms of processing? Or are there several structures in the brain involved simultaneously? And in that case, do they have other functions apart from that?
A search in MEDLINE and PsychInfo for studies combining fMRI and sadness, excluding those related to depression or other psychiatric disorders led to 12 studies in total. All studies included healthy subjects, measured BOLD signal activations, of which only the significant ones were studied.
In several studies, a priori Regions Of Interest (ROI) were determined based on findings from previous studies.
The results do not find a single structure correlated to sadness. Moreover, none of the structures found in the studies was present in all 12. All studies showed several areas involved. Some studies showed sex differences in BOLD signal activation. Several studies show significant activation in areas outside of the predetermined ROIs.
Based on the results, there is no evidence of a sole neural substrate for sadness. It is more likely that several structures are involved in that processing, constituting a network. The structures lie in cortical, subcortical and paralimbic regions: the amygdala, the temporal lobe, mainly the superolateral regions, the frontal lobe especially the medial prefrontal cortex, the limbic lobe (anterior and posterior cingulate, the hippocampus), insula and other subcortical structures.