Cortex; a journal devoted to the study of the nervous system and behavior
September 1, 2023
Jianghao Liu, Paolo Bartolomeo
68 citations
People with aphantasia, who report absent or nearly absent visual imagery, perform as accurately as typical and unusually vivid imagers on tasks involving object shape, color, written words, faces, and spatial relationships. However, they respond more slowly on both imagery and perceptual tasks, and they report lower confidence in their perceptual judgments. Across all participants, higher vividness of imagery correlates with faster response times. The findings suggest that congenital aphantasia involves slower visual information processing in both imagery and perception, but the precision of that processing is unaffected. This pattern supports the idea that aphantasia may stem from a deficit in phenomenal consciousness or the use of alternative non-visual strategies.
The Journal of neuroscience : the official journal of the Society for Neuroscience
May 27, 2026
Alfredo Spagna, Jianghao Liu, Paolo Bartolomeo
Conscious perception is preceded by distinct patterns of brain activity that depend on whether attention is oriented to the correct location or must be reoriented. Using magnetoencephalography, the study examined neural oscillations before near-threshold visual targets. Validly cued targets (67% of trials) were preceded by early beta-band activity in the right superior parietal lobule about 58 milliseconds after the cue. Invalidly cued targets that were reported were preceded by later beta activity in the right temporo-occipital region, theta-gamma phase-amplitude coupling in the right lateral visual cortex, and low gamma coherence between that region and the left temporoparietal junction.
Neuroscience of consciousness
January 1, 2026
Silvana Lozito, Stefano Lasaponara, Jianghao Liu et al.
Surface EEG recordings from 10 patients, previously studied with intracerebral electrodes, were analyzed to bridge the gap between depth and scalp measures of conscious report. Pooling trials across participants, event-related potentials showed a significant positive deflection for Seen compared to Unseen targets at frontal sites 350-500 milliseconds after the target, consistent with a P3b component. Time-frequency analysis revealed pretarget beta/gamma power modulations at frontal electrodes and post-target increased oscillatory activity at occipital sites. Clustering of intracerebral data identified two patterns: an early Visual cluster (120-340 ms) and a later Accumulation cluster (230-490 ms). Ridge regression showed the Accumulation cluster contributed more to predicting scalp ERPs, highlighting the greater role of late integrative mechanisms over early sensory processes in conscious experience.