Pregnant women in their first trimester experience fewer nightmares than non-pregnant counterparts, with 100 participants in each group revealing significant differences. While only 23% of pregnant women reported frequent nightmares, this contrasts sharply with 43% in the control group. Additionally, those with depressive symptoms and greater dream engagement were more likely to have nightmares. The findings suggest that hormonal changes during gestation may reduce oneiric activity, supporting the continuity hypothesis that links depression with nightmare frequency.
Surface EEG recordings from 10 patients, previously studied with intracerebral electrodes, were analyzed to bridge the gap between depth and scalp measures of conscious report. Pooling trials across participants, event-related potentials showed a significant positive deflection for Seen compared to Unseen targets at frontal sites 350-500 milliseconds after the target, consistent with a P3b component. Time-frequency analysis revealed pretarget beta/gamma power modulations at frontal electrodes and post-target increased oscillatory activity at occipital sites. Clustering of intracerebral data identified two patterns: an early Visual cluster (120-340 ms) and a later Accumulation cluster (230-490 ms). Ridge regression showed the Accumulation cluster contributed more to predicting scalp ERPs, highlighting the greater role of late integrative mechanisms over early sensory processes in conscious experience.