In addition to sensory inputs, the visual cortex receives large amounts of feedback (top-down signals) from other cortical areas. This feedback plays a crucial functional role for percepts when sensory signals are noisy, ambiguous, or complex, which can be uncovered in visual illusions . In some instances, top-down signals can give rise to rich and realistic visual experiences in the case of hallucinations. This occurs with high prevalence in people with severe vision loss but otherwise neurologically healthy (Charles Bonnet Syndrome) , and can be induced artificially via perceptual deprivation and hallucinogenic substances in controls [3,4,5]. How these experiences differ from each other and normal vision, and how and why they emerge, is currently poorly understood. The aim of the PhD is to investigate internally-driven visual percepts in health and eye disease, by investigating how brain activation (using MRI and EEG) and perceptual experiences (using psychophysics and self-report) during vivid, internally-driven vision differ from those during normal vision in terms of neural dynamics and information processing in visual cortex.
 Kok, P., Bains, L. J., van Mourik, T., Norris, D. G., & de Lange, F. P. (2016). Selective activation of the deep layers of the human primary visual cortex by top-down feedback. Current Biology, 26(3), 371-376.
 Hahamy, A., Wilf, M., Rosin, B., Behrmann, M., & Malach, R. (2021). How do the blind ‘see’? The role of spontaneous brain activity in self-generated perception. Brain, 144(1), 340-353.
 Schmidt, T. T., Jagannathan, N., Ljubljanac, M., Xavier, A., & Nierhaus, T. (2020). The multimodal Ganzfeld-induced altered state of consciousness induces decreased thalamo-cortical coupling. Scientific Reports, 10(1), 1-10.
 Carhart-Harris, R. L., Muthukumaraswamy, S., Roseman, L., Kaelen, M., Droog, W., Murphy, K., … & Nutt, D. J. (2016). Neural correlates of the LSD experience revealed by multimodal neuroimaging. Proceedings of the National Academy of Sciences, 113(17), 4853-4858.
 Gallimore, A. R., & Strassman, R. J. (2016). A Model for the Application of Target-Controlled Intravenous Infusion for a Prolonged Immersive DMT Psychedelic Experience. Frontiers in Pharmacology, 7, 211.
 Gravel, N., Harvey, B., Nordhjem, B., Haak, K. V., Dumoulin, S. O., Renken, R., … & Cornelissen, F. W. (2014). Cortical connective field estimates from resting state fMRI activity. Frontiers in neuroscience, 8, 339.
 Kay KN, Naselaris T, Prenger RJ, Gallant JL. Identifying natural images from human brain activity. Nature. 2008 Mar 20;452(7185):352-5. doi: 10.1038/nature06713. Epub 2008 Mar 5. PMID: 18322462; PMCID: PMC3556484.
 Wen, H., Shi, J., Zhang, Y., Lu, K.-H., Cao, J., & Liu, Z. (2018). Neural Encoding and Decoding with Deep Learning for Dynamic Natural Vision. Cerebral Cortex , 28(12), 4136–4160.
 Aliko, S., Huang, J., Gheorghiu, F., Meliss, S., & Skipper, J. I. (2020). A naturalistic neuroimaging database for understanding the brain using ecological stimuli. Nature Scientific Data, 7(1), 347.