Functional connectivity supporting emotion perception, and resting state networks in typically developing neonates and following prenatal exposure to maternal mood disturbances and SSRIs (2019)
The first year of life is a period of dramatic structural changes in the brain. Along with structural changes, infants achieve significant behavioral milestones. The bridge between brain structure and behavior is strongly based on functional connections that enable intrinsic functioning and also develop emotion perception skills, both critical for early development. However, little is known about how these connections are functionally organized in infancy. Prenatal exposures to maternal mood disturbances and the use of selective serotonin reuptake inhibitor (SSRI) antidepressants play a crucial role in shaping infants’ development, although it remains unclear how these exposures are linked to infant developmental outcomes. In this thesis, I use task-based electroencephalography (EEG) and resting-state functional magnetic resonance imaging (rs-fMRI) combined with graph theory analysis to study the functional networks of emotion perception and the intrinsic functional connectivity of resting state networks (RSNs) in typically developing infants and in infants prenatally exposed to mood disturbances and SSRIs. I found that 8-to-10-month-old infants have network characteristics that are similar to adults when observing basic emotions (Chapter 3). Moreover, an increase in prenatal maternal mood symptoms was associated with reduced modularity only for negative emotions, while prenatal SSRI drug-exposure was associated with higher network modularity in observing both positive and negative emotions. In contrast, higher postnatal mood symptoms were associated with alterations in frontal hubs (Chapter 5). Prenatal mood disturbances were associated with alterations in intrinsic RSNs. Specifically, compared to the control group, infants exposed to prenatal maternal depression showed higher hub values of the left anterior-cingulate, insula, and caudate as well as higher hub values in the amygdala (Chapter 7). Prenatal SSRI exposure associated both with higher hub values in Heschel’s gyrus (Chapter 7) and with hyperconnectivity of the putative auditory network (Chapter 6) possibly support shifts in language perception previously reported in infants exposed to prenatal SSRI. Collectively, these data indicate that the core functional organization for observing basic emotions is in place at 8-to-10 months of age. Further, maternal mood disturbances and SSRI exposure may differently shape early intrinsic and emotion perception functional organization, possibly leading to different developmental trajectories.