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Abdelrahman Sharafeldin

3 papers in the library · 102 citations · publishing 2023-2025

Papers

Adversarial testing of global neuronal workspace and integrated information theories of consciousness.

Nature June 1, 2025 Oscar Ferrante, Urszula Gorska-Klimowska, Simon Henin et al. 94 citations

Different theories explain how subjective experience arises from brain activity. An open science adversarial collaboration directly juxtaposed integrated information theory (IIT) and global neuronal workspace theory (GNWT). Human participants (n = 256) viewed suprathreshold stimuli for variable durations while neural activity was measured with fMRI, MEG, and intracranial EEG. Information about conscious content was found in visual, ventrotemporal, and inferior frontal cortex, with sustained responses in occipital and lateral temporal cortex reflecting stimulus duration, and content-specific synchronization between frontal and early visual areas. These results align with some predictions of IIT and GNWT but substantially challenge key tenets of both theories, including a lack of sustained posterior cortex synchronization for IIT and a lack of ignition at stimulus offset and limited prefrontal representation for GNWT.

Slow and fast cortical cholinergic arousal is reduced in a mouse model of focal seizures with impaired consciousness.

Cell reports December 24, 2024 Lim-Anna Sieu, Shobhit Singla, Jiayang Liu et al. 8 citations

Focal temporal lobe seizures in humans often cause loss of consciousness accompanied by cortical slow waves similar to deep sleep. Previous rat studies under anesthesia suggested that reduced subcortical arousal depresses cortical function, but could not link conscious behavior to physiology. In an awake mouse model, electrically induced hippocampal seizures impaired behavioral responses to sounds, triggered cortical slow waves, and reduced mean high-frequency cortical activity. Behavioral responses depended on cortical acetylcholine release at two timescales: slow state-related decreases correlated with overall impairment, while fast phasic release corresponded to variable spared or impaired responses per stimulus. These results establish a strong link between decreased cortical arousal and impaired consciousness during focal seizures.

An adversarial collaboration to critically evaluate theories of consciousness

bioRxiv Preprint Server June 23, 2023 Oscar Ferrante, Urszula Gorska-Klimowska, Simon Henin et al. preprint

An open science adversarial collaboration directly juxtaposed Integrated Information Theory (IIT) and Global Neuronal Workspace Theory (GNWT) by investigating neural correlates of visual experience. 256 human subjects viewed suprathreshold stimuli for variable durations while neural activity was measured with fMRI, MEG, and ECoG. Information about conscious content was found in visual, ventro-temporal, and inferior frontal cortex, with sustained responses in occipital and lateral temporal cortex reflecting stimulus duration, and content-specific synchronization between frontal and early visual areas.