Brain stimulation and conscious experience: Electrical stimulation of the cortical surface at a threshold current evokes sustained neuronal activity only after a prolonged latency
David Bourget (Western Ontario)
David Chalmers (ANU, NYU)
Rafael De Clercq
Jack Alan Reynolds
Learn more about PhilPapers
Consciousness and Cognition 15 (3):560-565 (2006)
Libet demonstrated that a substantial duration (>0.5-1.0 s) of direct electrical stimulation of the surface of a sensory cortex at a threshold or liminal current is required before a subject can experience a percept. Libet and his co-workers originally proposed that the result could be due either to spatial and temporal facilitation of the underlying neurons or additionally to a prolonged central processing time. However, over the next four decades, Libet chose to attribute the prolonged latency for evoking conscious experience to a prolonged central processing time. In my view, Libet has not provided any convincing evidence, either on the basis of his own past work or in his critique of my paper, for his hypothesis of a central processing time exceeding 0.5s before conscious experience emerges following direct electrical threshold stimulation of the cortical surface. I stand by my original results and conclusion that such prolonged latencies are largely the consequence of a dynamically increasing cortical facilitatory process that begins hundreds of milliseconds before there is a sustained neuronal activation. In some cases, the facilitatory process must overcome an initial stimulus-induced inhibition before neuronal firing commences
|Keywords||*Brain Stimulation *Consciousness States *Motor Processes *Stimulus Duration *Visual Cortex Reaction Time Self Perception Visual Perception Volition|
|Categories||categorize this paper)|
Setup an account with your affiliations in order to access resources via your University's proxy server
Configure custom proxy (use this if your affiliation does not provide a proxy)
|Through your library|
References found in this work BETA
No references found.
Citations of this work BETA
No citations found.
Similar books and articles
R. Nijhawan & B. Khurana (2000). Conscious Registration of Continuous and Discrete Visual Events. In Thomas Metzinger (ed.), Neural Correlates of Consciousness. MIT Press.
T. W. Kjaer, M. Nowak, K. W. Kjaer, A. R. Lou & H. C. Lou (2001). Precuneus-Prefrontal Activity During Awareness of Visual Verbal Stimuli. Consciousness and Cognition 10 (3):356-365.
Gilles Pourtois, Michael De Pretto, Claude-Alain Hauert & Patrik Vuilleumier (2006). Time Course of Brain Activity During Change Blindness and Change Awareness: Performance is Predicted by Neural Events Before Change Onset. Journal of Cognitive Neuroscience 18 (12):2108-2129.
Ramesh Srinivasan & Sanja Petrovic (2006). Meg Phase Follows Conscious Perception During Binocular Rivalry Induced by Visual Stream Segregation. Cerebral Cortex 16 (5):597-608.
Daniel Alroy (1995). Inner Light. Synthese 104 (1):147-160.
Gilberto Gomes (1998). The Timing of Conscious Experience: A Critical Review and Reinterpretation of Libet's Research. Consciousness and Cognition 7 (4):559-595.
Morten Overgaard, Jorgen Feldbaek Nielsen & Anders Fuglsang-Frederiksen (2004). A TMS Study of the Ventral Projections From V1 with Implications for the Finding of Neural Correlates of Consciousness. Brain and Cognition 54 (1):58-64.
Susan Pockett (2006). The Great Subjective Back-Referral Debate: Do Neural Responses Increase During a Train of Stimuli? Consciousness and Cognition 15 (3):551-559.
David A. Oakley & Patrick Haggard (2006). The Timing of Brain Events: Authors' Response to Libet's 'Reply'. Consciousness and Cognition 15 (3):548-550.
Daniel A. Pollen (2004). Brain Stimulation and Conscious Experience. Consciousness and Cognition 13 (3):626-645.
Added to index2009-01-28
Total downloads21 ( #81,620 of 1,101,575 )
Recent downloads (6 months)4 ( #81,941 of 1,101,575 )
How can I increase my downloads?