eLife
May 28, 2025
Johannes Jacobus Fahrenfort, Philippa A Johnson, Niels A Kloosterman et al.
10 citations
Conservative response criterion placement unexpectedly inflates effect sizes in neural measures of both conscious and unconscious processing, while liberal criterion placement reduces them. Simulations and electroencephalography decoding analyses from two studies using common subjective awareness indicators confirm these confounding effects. The widely used Perceptual Awareness Scale (PAS) does not protect against criterion confounds. Follow-up simulations show that the experimental context determines whether the confounding effect is larger for conscious or unconscious neural measures. Criterion placement threatens the construct validity of neural measures of consciousness.
Cognitive neuroscience
January 1, 2021
Yair Pinto, Timo Stein
7 citations
The paper argues that the approach of setting aside the hard problem of consciousness—the question of why and how physical processes give rise to subjective experience—to focus only on measuring neural and functional correlates is not feasible. While some researchers advocate 'shut up and measure' as a pragmatic strategy, the authors contend that any data collection about consciousness necessarily involves an implicit or explicit stance on the hard problem itself. Thus, the hard problem cannot be bypassed through purely empirical methods.
eLife
June 18, 2025
Samuel Noorman, Timo Stein, Jasper Zantvoord et al.
2 citations
Perceptual inference—how the brain integrates visual features into a coherent whole—depends on recurrent processing, the back-and-forth communication between higher and lower cortical regions. Animal studies have implicated NMDA receptors in this process, but human evidence was lacking. In two double-blind, placebo-controlled experiments with healthy participants, the NMDA receptor antagonist memantine selectively improved the brain's ability to decode complex visual illusions (Kanizsa triangles) that require recurrent processing, while leaving simpler visual processing (contrast and collinearity) unaffected. This enhancement occurred only when stimuli were attended and consciously perceived. The findings suggest that blocking NMDA receptors can enhance recurrent processing for attended objects, linking animal and human research on the neural basis of conscious perception.
bioRxiv Preprint Server
February 22, 2024
Johannes J. Fahrenfort, Philippa A. Johnson, Niels A. Kloosterman et al.
preprint
Conservative criterion placement in subjective awareness judgments inflates neural effect sizes for both conscious and unconscious processing, while liberal placement reduces them. Simulations and two EEG studies show that the commonly used Perceptual Awareness Scale does not protect against this confound. The findings indicate that response criterion placement threatens the construct validity of neural measures of consciousness.