Altered functional connectivity and network efficiency in prenatal depression: an functional near-infrared spectroscopy study.

This study investigated the impact of prenatal depression on brain function in pregnant women using functional near-infrared spectroscopy (fNIRS). Functional signals were recorded during resting-state and sadness/happiness video stimulus tasks in prenatal depression group (n = 22) and healthy controls (n = 31). Compared with controls, the prenatal depression group showed a significantly lower mean total hemoglobin (HbT) signal in the visual cortex (P = 0.029) during the resting-state condition, as well as the HbT slope of the primary motor cortex (P = 0.035) under the happiness video stimulus. Deoxyhemoglobin-based functional connectivity analysis showed that, during the sadness video stimulus, the prenatal depression group exhibited reduced connectivity between the left motor area and the left prefrontal cortex (-0.019 ± 0.077 vs. 0.098 ± 0.124, P = 0.0031) as well as the right prefrontal cortex (-0.038 ± 0.086 vs. 0.081 ± 0.134, P = 0.0127). Graph theory analysis showed higher characteristic path length and lower global efficiency in the prenatal depression group than in controls, under both sadness (all P < 0.01) and happiness (all P < 0.05) conditions. These findings indicate altered regional brain activity patterns in pregnant women with prenatal depression, providing insight into the neural mechanisms underlying prenatal depression.