We used functional magnetic resonance imaging (fMRI) and event-related potentials (ERPs) to visualize the cerebral processing of unseen masked words. Within the areas associated with conscious reading, masked words activated left extrastriate, fusiform and precentral areas. Furthermore, masked words reduced the amount of activation evoked by a subsequent conscious presentation of the same word. In the left fusiform gyrus, this repetition suppression phenomenon was independent of whether the prime and target shared the same case, indicating that case-independent information about letter strings was extracted unconsciously. In comparison to an unmasked situation, however, the activation evoked by masked words was drastically reduced and was undetectable in prefrontal and parietal areas, correlating with participants' inability to report the masked words.
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Forster, K. I. & Davis, C. Repetition priming and frequency attenuation in lexical access. J. Exp. Psychol. Learn. Mem. Cogn. 10, 680–698 (1984).
Ferrand, L. & Grainger, J. Effects of orthography are independent of phonology in masked form priming. Q. J. Exp. Psychol. A 47, 365–382 (1994).
Bowers, J. S., Vigliocco, G. & Haan, R. Orthographic, phonological, and articulatory contributions to masked letter and word priming. J. Exp. Psychol. Hum. Percept. Perf. 24, 1705–1719 (1998).
Cheesman, J. & Merikle, P. M. Priming with and without awareness. Percept. Psychophys. 36, 387–395 (1984).
Greenwald, A. G. Three cognitive markers of unconscious semantic activation. Science 273, 1699–1702 (1996).
Dehaene, S. et al. Imaging unconscious semantic priming. Nature 395, 597–600 (1998).
Fiez, J. A. & Petersen, S. E. Neuroimaging studies of word reading. Proc. Natl. Acad. Sci. USA 95, 914–921 (1998).
Cohen, L. et al. The visual word form area: spatial and temporal characterization of an initial stage of reading in normal subjects and posterior split-brain patients. Brain 123, 291–307 (2000).
Wiggs, C. L. & Martin, A. Properties and mechanisms of perceptual priming. Curr. Opin. Neurobiol. 8, 227–233 (1998).
Lueschow, A., Miller, E. K. & Desimone, R. Inferior temporal mechanisms for invariant object recognition. Cereb. Cortex 4, 523–531 (1994).
Buckner, R. L. et al. Functional-anatomic correlates of object priming in humans revealed by rapid presentation event-related fMRI. Neuron 20, 285–296 (1998).
Grill-Spector, K. et al. Differential processing of objects under various viewing conditions in the human lateral occipital complex. Neuron 24, 187–203 (1999).
Schacter, D. L. & Buckner, R. L. Priming and the brain. Neuron 20, 185–195 (1998).
Gauthier, I. et al. The fusiform “face area” is part of a network that processes faces at the individual level. J. Cogn. Neurosci. 12, 495–504 (2000).
Schnyer, D. M., Allen, J. J. & Forster, K. I. Event-related brain potential examination of implicit memory processes: masked and unmasked repetition priming. Neuropsychology 11, 243–260 (1997).
Deacon, D., Hewitt, S., Yang, C. & Nagata, M. Event-related potential indices of semantic priming using masked and unmasked words: evidence that the N400 does not reflect a post-lexical process. Brain. Res. Cogn. Brain. Res. 9, 137–146 (2000).
Naccache, L. & Dehaene, S. The priming method: imaging unconscious repetition priming reveals an abstract representation of number in the parietal lobes. Cereb. Cortex (in press).
Kiefer, M. & Spitzer, M. Time course of conscious and unconscious semantic brain activation. Neuroreport 11, 2401–2407 (2000).
Rolls, E. T. & Tovee, M. J. Processing speed in the cerebral cortex and the neurophysiology of visual masking. Proc. R. Soc. Lond. B Biol. Sci. 257, 9–15 (1994).
Rolls, E. T., Tovee, M. J. & Panzeri, S. The neurophysiology of backward visual masking: information analysis. J. Cogn. Neurosci. 11, 300–311 (1999).
Marsolek, C. J., Kosslyn, S. M. & Squire, L. R. Form-specific visual priming in the right cerebral hemisphere. J. Exp. Psychol. Learn. Mem. Cogn. 18, 492–508 (1992).
Compton, P. E., Grossenbacher, P., Posner, M. I. & Tucker, D. M. A cognitive-anatomical approach to attention in lexical access. J. Cogn. Neurosci. 3, 304–312 (1991).
Posner, M. I. & McCandliss, B. D. Converging methods for investigating lexical access. Psychol. Sci. 4, 305–309 (1993).
Marsolek, C. J. Abstract visual-form representations in the left cerebral hemisphere. J. Exp. Psychol. Hum. Percept. Perf. 21, 375–386 (1995).
Fiez, J. A., Balota, D. A., Raichle, M. E. & Petersen, S. E. Effects of lexicality, frequency, and spelling-to-sound consistency on the functional anatomy of reading. Neuron 24, 205–218 (1999).
Tong, F., Nakayama, K., Vaughan, J. T. & Kanwisher, N. Binocular rivalry and visual awareness in human extrastriate cortex. Neuron 21, 753–759 (1998).
Grill-Spector, K., Kushnir, T., Hendler, T. & Malach, R. The dynamics of object-selective activation correlate with recognition performance in humans. Nat. Neurosci. 3, 837–843 (2000).
Leopold, D. A. & Logothetis, N. K. Multistable phenomena: changing views in perception. Trends Cogn. Sci. 3, 254–264 (1999).
Bar, M. & Biederman, I. Localizing the cortical region mediating visual awareness of object identity. Proc. Natl. Acad. Sci. USA 96, 1790–1793 (1999).
Bar, M. et al. Cortical mechanisms specific to explicit visual object recognition. Neuron 29, 529–535 (2001).
Friston, K. J., Josephs, O., Rees, G. & Turner, R. Nonlinear event-related responses in fMRI. Magn. Reson. Med. 39, 41–52 (1998).
Macknik, S. L. & Livingstone, M. S. Neuronal correlates of visibility and invisibility in the primate visual system. Nat. Neurosci. 1, 144–149 (1998).
Breitmeyer, B. G. Visual Masking: An Integrative Approach (Oxford Univ. Press, 1984).
Enns, J. T. & Di Lollo, V. What's new in visual masking. Trends Cogn. Sci. 4, 345–352 (2000).
Dehaene, S. & Naccache, L. Towards a cognitive neuroscience of consciousness: basic evidence and a workspace framework. Cognition 79, 1–37 (2001).
Donchin, E. & Coles, M. G. H. Is the P300 component a manifestation of context updating? Behav. Brain Sci. 11, 357–427 (1988).
Picton, T. W. The P300 wave of the human event-related potential. J. Clin. Neurophysiol. 9, 456–479 (1992).
Portas, C. M. et al. Auditory processing across the sleep-wake cycle: simultaneous EEG and fMRI monitoring in humans. Neuron 28, 991–999 (2000).
Rees, G., Russell, C., Frith, C. D. & Driver, J. Inattentional blindness versus inattentional amnesia for fixated but ignored words. Science 286, 2504–2507 (1999).
Lumer, E. D. & Rees, G. Covariation of activity in visual and prefrontal cortex associated with subjective visual perception. Proc. Natl. Acad. Sci. USA 96, 1669–1673 (1999).
McIntosh, A. R., Rajah, M. N. & Lobaugh, N. J. Interactions of prefrontal cortex in relation to awareness in sensory learning. Science 284, 1531–1533 (1999).
Driver, J. & Vuilleumier, P. Unilateral neglect and perceptual awareness. Cognition 79, 39–88 (2001).
Rees, G. et al. Unconscious activation of visual cortex in the damaged right hemisphere of a parietal patient with extinction. Brain 123, 1624–1633 (2000).
Posner, M. I. Attention: the mechanisms of consciousness. Proc. Natl. Acad. Sci. USA 91, 7398–7403 (1994).
Dehaene, S., Kerszberg, M. & Changeux, J. P. A neuronal model of a global workspace in effortful cognitive tasks. Proc. Natl. Acad. Sci. USA 95, 14529–14534 (1998).
Burock, M. A., Buckner, R. L., Woldorff, M. G., Rosen, B. R. & Dale, A. M. Randomized event-related experimental designs allow for extremely rapid presentation rates using functional MRI. Neuroreport 9, 3735–3739 (1998).
We thank J.-P. Changeux, C. Pallier and L. Spelke for useful comments. This project was supported by the McDonnell Foundation.
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Dehaene, S., Naccache, L., Cohen, L. et al. Cerebral mechanisms of word masking and unconscious repetition priming. Nat Neurosci 4, 752–758 (2001). https://doi.org/10.1038/89551
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