Model-based analyses of spatiotemporal brain activity during resting-state and low-level states of consciousness

López-González, Ane

Model-based analyses of spatiotemporal brain activity during resting-state and low-level states of consciousness

Document Type

Doctoral thesis
Published Version

Author

López-González, Ane

Director

Ponce Álvarez, Adrián
Deco, Gustavo

Publication Date

2021-10-06

Pages

221 p.

Citation

López-González, A. Model-based analyses of spatiotemporal brain activity during resting-state and low-level states of consciousness. 2021. handle: http://hdl.handle.net/10803/672766

This citation was generated automatically.

Doctoral program

Programa de doctorat en Biomedicina

Abstract

The brain’s resting-state activity displays complex spatiotemporal patterns of activity that are constantly formed and dissolved. The study of these dynamic collective patterns has increased our understanding of the brain's organization principles during function and dysfunction. However, the underlying mechanisms remain unknown. Theoretical whole-brain models explore this question by combining neural networks and brain activity/connectivity data. In the present thesis, I studied whole-brain models of resting-state activity during conscious wakefulness and low-level states of consciousness. I analyzed neuroimaging data (fMRI and EEG) from subjects during wakefulness and anesthesia, and from patients with disorders of consciousness due to brain lesions. I interpreted the results using diverse models to disentangle the contribution of brain dynamics, network connectivity, and temporal scales. The results suggest that loss of consciousness is driven by altered network interactions, more homogeneous and structurally constrained local dynamics, and less stability of the network’s topological core compared to conscious states.
La actividad cerebral en reposo muestra patrones espacio-temporales complejos que se forman y desvanecen constantemente. El estudio de estos patrones ha impulsado nuestro conocimiento sobre la organización del cerebro durante su función y disfunción. Sin embargo, los mecanismos subyacentes aún no han sido revelados. Los modelos teóricos cerebrales a gran escala exploran esta cuestión combinando redes neuronales y datos de actividad/conectividad. Aquí, examino modelos cerebrales de actividad en reposo durante estados de vigilia y baja conciencia. Específicamente, analizo datos de neuroimagen (fMRI y EEG) de sujetos durante estados conscientes y anestesiados, y pacientes con desórdenes de conciencia provocados por lesiones. Interpreto estos resultados usando diversos modelos que disocian contribuciones dinámicas, de conectividad y escala temporal. Los resultados sugieren que la pérdida de conciencia es debida a alteraciones en las interacciones de la red, a dinámicas locales más homogéneas y acotadas a la estructura, y a una menor estabilidad del núcleo topológico.

Keywords

Whole-brain spatiotemporal activity, Consciousness, Disorders of Consciousness, Anesthesia, Whole-brain modelling, Actividad cerebral espaciotemporal a gran escala, Conciencia, Desórdenes de conciencia, Anestesia, Modelos a gran escala