Amygdala and hippocampus volumetry and diffusivity in relation to dreaming
Luigi De Gennaro, Carlo Cipolli, Andrea Cherubini, Francesca Assogna, Claudia Cacciari, Cristina Marzano, Giuseppe Curcio, Michele Ferrara, Carlo Caltagirone, Gianfranco Spalletta
Human Brain Mapping August 25, 2010 DOI: 10.1002/hbm.21120 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Qualitative Peer reviewed |
|---|---|
| Sample size | 34 |
| Population | Healthy subjects aged 20s to 70s |
| Duration | Two weeks |
| Topics | Dreaming |
| Citations | 79 |
| Key findings | Dream recall frequency showed no significant relationship with amygdala or hippocampus measures, but qualitative features did: higher left amygdala mean diffusivity was associated with shorter dream reports and lower emotional load, and bizarreness correlated negatively with left amygdala volume and positively with right amygdala mean diffusivity. |
Abstract
Microstructural analyses by MRI brain scans and by DTI analysis of MR images were used to investigate the possible relationship between deep gray matter structures (amygdala and hippocampus) and dreaming in healthy subjects. Thirty-four subjects ranging in age 20s to 70s underwent to a MRI protocol for the assessment of volume and mean diffusivity (MD) in the amygdala and hippocampus and were asked to fill out a dream diary via audiotape recording upon morning awakening for two weeks. Multiple regression analyses evaluated the relationships between anatomical measures and quantitative and qualitative measures of the reported dreams. The main result points to a dissociation between some quantitative and qualitative aspects of dream reports. While the mean number of dreams recalled per day did not show any significant relationship with the neuroanatomical measures, significant associations with some qualitative features of the recalled dreams (emotional load, bizarreness, and vividness) and, to some extent, with the length of dream reports were observed. Particularly, a higher MD of the left amygdala, reflecting a decreased microstructural integrity, was associated with shorter dream reports and lower scores on emotional load. Bizarreness of dream reports was negatively correlated with the left amygdala volume and positively correlated with the right amygdala MD. Some specific, although weaker, relationships were also found between bizarreness and hippocampal measures. These findings indicate some direct relationships between volumetric and ultrastructural measures of the hippocampus-amygdala complex and specific qualitative features of dreaming.