Alteration of consciousness in focal epilepsy: The global workspace alteration theory

Alteration of consciousness (AOC) is an important clinical manifestation of partial seizures that greatly impacts the quality of life of patients with epilepsy. Several theories have been proposed in the last fifty years. An emerging concept in neurology is the global workspace (GW) theory that postulates that access to consciousness (from several sensorial modalities) requires transient coordinated activity from associative cortices, in particular the prefrontal cortex and the posterior parietal associative cortex. Several lines of evidence support the view that partial seizures alter consciousness through disturbance of the GW. In particular, a nonlinear relation has been shown between excess of synchronization in the GW regions and the degree of AOC. Changes in thalamocortical synchrony occurring during the spreading of the ictal activity seem particularly involved in the mechanism of altered consciousness. This link between abnormal synchrony and AOC offers new perspectives in the treatment of the AOC since means of decreasing consciousness alteration in seizures could improve patients' quality of life.

[1]  Hal Blumenfeld,et al.  Impaired consciousness in epilepsy investigated by a prospective responsiveness in epilepsy scale (RES) , 2012, Epilepsia.

[2]  L. Cohen,et al.  Cueing Attention after the Stimulus Is Gone Can Retrospectively Trigger Conscious Perception , 2013, Current Biology.

[3]  F. Bartolomei,et al.  Alteration of global workspace during loss of consciousness: A study of parietal seizures , 2012, Epilepsia.

[4]  B. Baars.  A cognitive theory of consciousness , 1988 .

[5]  J. Régis,et al.  The role of corticothalamic coupling in human temporal lobe epilepsy. , 2006, Brain : a journal of neurology.

[6]  Sung-Bae Cho,et al.  A Neural Global Workspace Model for Conscious Attention , 1997, Neural Networks.

[7]  L. Naccache,et al.  Imaging neural signatures of consciousness: 'what', 'when', 'where' and 'how' does it work? , 2012, Archives italiennes de biologie.

[8]  P. Gloor,et al.  Consciousness as a Neurological Concept in Epileptology: A Critical Review , 1986, Epilepsia.

[9]  S. Dehaene,et al.  Converging Intracranial Markers of Conscious Access , 2009, PLoS biology.

[10]  S Dehaene,et al.  A neuronal model of a global workspace in effortful cognitive tasks. , 1998, Proceedings of the National Academy of Sciences of the United States of America.

[11]  Kaspar Anton Schindler,et al.  Synchronization and desynchronization in epilepsy: controversies and hypotheses , 2012, The Journal of physiology.

[12]  A. Cavanna,et al.  Measuring the level and content of consciousness during epileptic seizures: The Ictal Consciousness Inventory , 2008, Epilepsy & Behavior.

[13]  S. Dehaene,et al.  Timing of the brain events underlying access to consciousness during the attentional blink , 2005, Nature Neuroscience.

[14]  B. Baars.  The conscious access hypothesis: origins and recent evidence , 2002, Trends in Cognitive Sciences.

[15]  Kimron Shapiro,et al.  Modulation of long-range neural synchrony reflects temporal limitations of visual attention in humans. , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[16]  Colin Studholme,et al.  Positive and negative network correlations in temporal lobe epilepsy. , 2004, Cerebral cortex.

[17]  M. Boly,et al.  Tracking the recovery of consciousness from coma. , 2006, The Journal of clinical investigation.

[18]  Fabrice Bartolomei,et al.  Semiologic and Electrophysiologic Correlations in Temporal Lobe Seizure Subtypes , 2004, Epilepsia.

[19]  K. Meador,et al.  Pathophysiology of altered consciousness during seizures: Subtraction SPECT study , 2002, Neurology.

[20]  P. Fries.  A mechanism for cognitive dynamics: neuronal communication through neuronal coherence , 2005, Trends in Cognitive Sciences.

[21]  D. Mogul,et al.  Modulation of Instantaneous Synchrony During Seizures by Deep Brain Stimulation , 2009, 2009 Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

[22]  J. Régis,et al.  Epileptogenic networks in seizures arising from motor systems , 2013, Epilepsy Research.

[23]  S. Dehaene,et al.  Towards a cognitive neuroscience of consciousness: basic evidence and a workspace framework , 2001, Cognition.

[24]  S. Dehaene,et al.  Brain Dynamics Underlying the Nonlinear Threshold for Access to Consciousness , 2007, PLoS biology.

[25]  Catherine Tallon-Baudry,et al.  The many faces of the gamma band response to complex visual stimuli , 2005, NeuroImage.

[26]  S. Dehaene,et al.  Event related potentials elicited by violations of auditory regularities in patients with impaired consciousness , 2012, Neuropsychologia.

[27]  J. Changeux,et al.  Opinion TRENDS in Cognitive Sciences Vol.10 No.5 May 2006 Conscious, preconscious, and subliminal processing: a testable taxonomy , 2022 .

[28]  Fabrice Wendling,et al.  Abnormal binding and disruption in large scale networks involved in human partial seizures , 2013 .

[29]  Stanislas Dehaene,et al.  Preserved subliminal processing and impaired conscious access in schizophrenia. , 2006, Archives of general psychiatry.

[30]  Fabrice Wendling,et al.  Impaired consciousness during temporal lobe seizures is related to increased long-distance cortical-subcortical synchronization. , 2009, Brain : a journal of neurology.

[31]  G. Jackson,et al.  Commentary – Should consciousness be included in the classification of focal (partial) seizures? , 2013, Epilepsia.

[32]  S. Bressler,et al.  Beta oscillations in a large-scale sensorimotor cortical network: directional influences revealed by Granger causality. , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[33]  François Mauguière,et al.  Involvement of Medial Pulvinar Thalamic Nucleus in Human Temporal Lobe Seizures , 2006, Epilepsia.

[34]  S. Dehaene,et al.  Neural signature of the conscious processing of auditory regularities , 2009, Proceedings of the National Academy of Sciences.

[35]  Hal Blumenfeld,et al.  Why do Seizures Cause Loss of Consciousness? , 2003, The Neuroscientist : a review journal bringing neurobiology, neurology and psychiatry.

[36]  D. Spencer,et al.  Ictal neocortical slowing in temporal lobe epilepsy , 2004, Neurology.

[37]  L. Senhadji,et al.  From EEG signals to brain connectivity: A model-based evaluation of interdependence measures , 2009, Journal of Neuroscience Methods.

[38]  S. Dehaene,et al.  Probing consciousness with event-related potentials in the vegetative state , 2011, Neurology.

[39]  Fabrice Bartolomei,et al.  The Global Workspace (GW) Theory of Consciousness and Epilepsy , 2011, Behavioural neurology.

[40]  G. Edelman,et al.  Consciousness and Complexity , 1998 .

[41]  O. Bertrand,et al.  Oscillatory Synchrony between Human Extrastriate Areas during Visual Short-Term Memory Maintenance , 2001, The Journal of Neuroscience.

[42]  Victor A. F. Lamme,et al.  Are There Multiple Visual Short-Term Memory Stores? , 2008, PloS one.

[43]  P. V. Van Ness,et al.  Cingulate epilepsy: report of 3 electroclinical subtypes with surgical outcomes. , 2013, JAMA neurology.

[44]  W. Freiwald,et al.  Oscillatory synchrony in the monkey temporal lobe correlates with performance in a visual short-term memory task. , 2004, Cerebral cortex.

[45]  M. Brazier.  Spread of seizure discharges in epilepsy: anatomical and electrophysiological considerations. , 1972, Experimental neurology.

[46]  A. Cavanna,et al.  Brain mechanisms of altered conscious states during epileptic seizures , 2009, Nature Reviews Neurology.

[47]  C. Elger,et al.  The localizing value of ictal consciousness and its constituent functions: a video-EEG study in patients with focal epilepsy. , 2002, Brain : a journal of neurology.

[48]  Walter G. Besio,et al.  Transcutaneous Focal Electrical Stimulation via Concentric Ring Electrodes Reduces Synchrony Induced by Pentylenetetrazole in beta and Gamma Bands in Rats , 2011, Int. J. Neural Syst..

[49]  J Bancaud,et al.  The clinical signs and symptoms of frontal lobe seizures. Phenomenology and classification. , 1995, Advances in neurology.

[50]  S. Smirnakis,et al.  Vagus nerve stimulation modulates cortical synchrony and excitability through the activation of muscarinic receptors , 2011, Neuroscience.

[51]  H. Blumenfeld,et al.  Consciousness and epilepsy: why are complex-partial seizures complex? , 2009, Progress in brain research.

[52]  J. Changeux,et al.  Experimental and Theoretical Approaches to Conscious Processing , 2011, Neuron.

[53]  T. Mihara,et al.  Awareness and Responsiveness During Partial Seizures , 1998, Epilepsia.

[54]  E. Miller,et al.  Top-Down Versus Bottom-Up Control of Attention in the Prefrontal and Posterior Parietal Cortices , 2007, Science.