Structural and Semantic Speech Graph Analysis of Dream Reports in Congenitally and Late Blind Individuals
Kausar Raheel, Nazanin Biabani, Olga Ivanenko, Qi Rui See, Rita Bertani, Valentina Gnoni, David O’Regan, Zoran Cvetković, Panagis Drakatos, Giulio Bernardi, Robert Leech, Carlos H. Schenck, Liborio Parrino, Peter J. Goadsby, Adam Ockelford, Ivana Rosenzweig
Research Square June 9, 2025 preprint DOI: 10.21203/rs.3.rs-6761771/v1 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational study |
|---|---|
| Sample size | 333 |
| Population | Dream reports from congenitally blind, late blind, and sighted control individuals drawn from the open-access DreamBank database |
| Measures | recurrence (L2/L3), connectivity (LSC), lexical diversity (nodes) |
| Key findings | Both congenitally and late blind groups showed reduced lexical diversity and increased long-range recurrence (LSC) in dream reports compared with sighted controls, suggesting greater linguistic cohesiveness; late blind reports also showed increased short-range recurrence cycles (L2, L3), not seen in congenitally blind reports. The authors argue these patterns are consistent with more egocentric narrative construction and suggest sensory experience may shape cognitive-linguistic encoding. |
Abstract
Abstract
Background: Visual input is thought to influence spatial cognition and language. While blind individuals often rely on egocentric spatial representations, it remains unclear whether and how visual deprivation affects dream-related language. This study applied speech graph analysis (SGA) to investigate linguistic differences in dream reports from congenitally blind (CB), late blind (LB), and sighted control (SC) individuals.
Methods: We retrospectively analyzed 333 dream reports from an open-access database (DreamBank): 118 from CB, 75 from LB, and 140 from SC individuals. Graph-theoretical metrics of structural and semantic speech organization were extracted using validated NLP and SGA pipelines, including recurrence (L2/L3), connectivity (LSC), and lexical diversity (nodes).
Results: Compared to SC, both CB and LB groups showed significantly reduced lexical diversity and increased long-range recurrence (LSC), suggesting greater linguistic cohesiveness. LB reports showed a specific increase in short-range recurrence cycles (L2, L3), not observed in CB. Spectral analysis supported these group differences, indicating altered graph-wide connectivity properties in blind groups.
Conclusions: Blind individuals demonstrate distinct structural and semantic features in dream-related language, consistent with more egocentric narrative construction. These findings support a potential role of sensory experience in shaping cognitive-linguistic encoding. Further prospective studies are needed to explore underlying neural mechanisms and developmental trajectories.
Citations in the library
Cites 5
- Dreaming as mind wandering: evidence from functional neuroimaging and first-person content reports. Frontiers in Human Neuroscience 2013
- Graph analysis of dream reports is especially informative about psychosis Scientific Reports January 15, 2014
- Visuo-spatial imagery in dreams of congenitally and early blind: a systematic review Frontiers in Integrative Neuroscience June 30, 2023
- Dreaming Characteristics in Non-Rapid Eye Movement Parasomnia and Idiopathic Rapid Eye Movement Sleep Behaviour Disorder: Similarities and Differences Nature and Science of Sleep March 1, 2024
- Dreaming and the brain: from phenomenology to neurophysiology. Trends in Cognitive Sciences January 14, 2010