Functional anomalies in healthy individuals with a first degree family history of major depressive disorder

Francesco Amico,Danuta Lisiecka,Angela Carballedo,Andrew J Fagan,Thomas Frodl,Gerard Boyle

doi:10.1186/2045-5380-2-1

Abstract

BackgroundIndividuals with major depressive disorder (MDD) process information with a bias towards negative stimuli. However, little is known on the link between vulnerability to MDD and brain functional anomalies associated with stimulus bias.MethodsA cohort of 38 subjects, of which 14 were patients with acute MDD and 24 were healthy controls (HC), were recruited and compared. The HC group included 10 healthy participants with a first degree family history of depression (FHP) and 14 volunteers with no family history of any psychiatric disease (FHN). Blood oxygen level dependence signals were acquired from functional magnetic resonance imaging (fMRI) during performance in a dot-probe task using fearful and neutral stimuli. Reaction times and the number of errors were also obtained.ResultsAlthough MDD patients and HC showed no behavioral difference, the MDD group exhibited smaller activation in the left middle cingulum. The MDD group also showed smaller activation in the left insula when compared to the HC group or the FHN group. Finally, FHP participants exhibited higher activation in the right Heschl's gyrus compared to FHN participants.ConclusionsThe present study shows that family risk for MDD is associated with increased activation in the Heschl's gyrus. Our results also suggest that acute MDD is linked to reduced activation in the insula and anterior cingulate cortex during processing of subliminal, not recognizable, masked fearful stimuli. Further research should confirm these results in a larger cohort of participants.

Highlights

Most conceptions of the relationship between mood and emotions suggest that moods may potentiate matching emotional reactions
family history of depression (FHP) subjects exhibit impairment in emotion recognition [6] and have been shown to have higher amygdala and nucleus accumbens activation in response to the presentation of fearful faces when compared to age-matched family history of any psychiatric disease (FHN) controls, in line with previous findings showing that FHP subjects have significantly elevated waking salivary cortisol when compared to FHN subjects [7]
FMRI data (Table 3) Contrast F > N major depressive disorder (MDD) patients exhibited smaller activation than healthy controls (HC) in the left middle cingulum (T = 3.82, P = 0.041, family-wise error (FWE) corrected for multiple comparisons) and left insula (T = 4.19, P < 0.001, uncorrected), which showed a trend for significance after correction for multiple comparisons (P = 0.072) (Figure 1)

Summary

Introduction

Most conceptions of the relationship between mood and emotions suggest that moods may potentiate matching emotional reactions (for example, irritable mood facilitates angry reactions [1]). When face viewing is accompanied by a constrained attention task (that is, having to rate nose width on the face and subjective fear while viewing the face), the differences between FHP and FHN subjects disappear whilst prefrontal activity increases [8] This suggests that FHP subjects may be able to normalize emotion-related neural functions by focusing their attention and that face-viewing with unconstrained attention may leave room for aberrant psychological processes associated with the risk for developing MDD [8]. Both behavioral and event related potential (ERP) studies have identified subtle deficits in selective attention among FHP individuals that may affect their ability to adequately regulate emotion under stressful circumstances [9]. Little is known on the link between vulnerability to MDD and brain functional anomalies associated with stimulus bias

Methods

Results

Discussion

Conclusion