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Páleník J. What does it mean for consciousness to be multidimensional? A narrative review. Front Psychol 2024; 15:1430262. [PMID: 38966739 PMCID: PMC11222411 DOI: 10.3389/fpsyg.2024.1430262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2024] [Accepted: 06/10/2024] [Indexed: 07/06/2024] Open
Abstract
A recent development in the psychological and neuroscientific study of consciousness has been the tendency to conceptualize consciousness as a multidimensional phenomenon. This narrative review elucidates the notion of dimensionality of consciousness and outlines the key concepts and disagreements on this topic through the viewpoints of several theoretical proposals. The reviewed literature is critically evaluated, and the main issues to be resolved by future theoretical and empirical work are identified: the problems of dimension selection and dimension aggregation, as well as some ethical considerations. This narrative review is seemingly the first to comprehensively overview this specific aspect of consciousness science.
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Affiliation(s)
- Julie Páleník
- First Department of Neurology, St. Anne’s University Hospital and Medical Faculty of Masaryk University, Brno, Czechia
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2
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Campora N, Princich JP, Nasimbera A, Cordisco S, Villanueva M, Oddo S, Giagante B, Kochen S. Stereo-EEG features of temporal and frontal lobe seizures with loss of consciousness. Neurosci Conscious 2024; 2024:niae003. [PMID: 38618487 PMCID: PMC11015893 DOI: 10.1093/nc/niae003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 12/11/2023] [Accepted: 04/03/2024] [Indexed: 04/16/2024] Open
Abstract
The loss of consciousness (LOC) during seizures is one of the most striking features that significantly impact the quality of life, even though the neuronal network involved is not fully comprehended. We analyzed the intracerebral patterns in patients with focal drug-resistant epilepsy, both with and without LOC. We assessed the localization, lateralization, stereo electroencephalography (SEEG) patterns, seizure duration, and the quantification of contacts exhibiting electrical discharge. The degree of LOC was quantified using the Consciousness Seizure Scale. Thirteen patients (40 seizures) with focal drug-resistant epilepsy underwent SEEG. In cases of temporal lobe epilepsy (TLE, 6 patients and 15 seizures), LOC occurred more frequently in seizures with mesial rather than lateral temporal lobe onset. On the other hand, in cases of frontal lobe epilepsy (7 patients; 25 seizures), LOC was associated with pre-frontal onset, a higher number of contacts with epileptic discharge compared to the onset count and longer seizure durations. Our study revealed distinct characteristics during LOC depending on the epileptogenic zone. For temporal lobe seizures, LOC was associated with mesial seizure onset, whereas in frontal lobe epilepsy, seizure with LOC has a significant increase in contact showing epileptiform discharge and a pre-frontal onset. This phenomenon may be correlated with the broad neural network required to maintain consciousness, which can be affected in different ways, resulting in LOC.
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Affiliation(s)
- Nuria Campora
- Neuroscience Department, El Cruce Hospital, Florencio Varela, Argentina
- Studies in Neuroscience and Complex Systems (ENyS), CONICET, Florencio Varela, Buenos Aires 1888, Argentina
| | - Juan Pablo Princich
- Neuroscience Department, El Cruce Hospital, Florencio Varela, Argentina
- Studies in Neuroscience and Complex Systems (ENyS), CONICET, Florencio Varela, Buenos Aires 1888, Argentina
| | - Alejandro Nasimbera
- Neuroscience Department, El Cruce Hospital, Florencio Varela, Argentina
- Studies in Neuroscience and Complex Systems (ENyS), CONICET, Florencio Varela, Buenos Aires 1888, Argentina
| | - Santiago Cordisco
- Studies in Neuroscience and Complex Systems (ENyS), CONICET, Florencio Varela, Buenos Aires 1888, Argentina
| | - Manuela Villanueva
- Studies in Neuroscience and Complex Systems (ENyS), CONICET, Florencio Varela, Buenos Aires 1888, Argentina
| | - Silvia Oddo
- Neuroscience Department, El Cruce Hospital, Florencio Varela, Argentina
- Studies in Neuroscience and Complex Systems (ENyS), CONICET, Florencio Varela, Buenos Aires 1888, Argentina
| | - Brenda Giagante
- Neuroscience Department, El Cruce Hospital, Florencio Varela, Argentina
| | - Silvia Kochen
- Neuroscience Department, El Cruce Hospital, Florencio Varela, Argentina
- Studies in Neuroscience and Complex Systems (ENyS), CONICET, Florencio Varela, Buenos Aires 1888, Argentina
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Cassady M, Baslet G. Dissociation in patients with epilepsy and functional seizures: A narrative review of the literature. Seizure 2023; 110:220-230. [PMID: 37433243 DOI: 10.1016/j.seizure.2023.06.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 06/18/2023] [Accepted: 06/24/2023] [Indexed: 07/13/2023] Open
Abstract
Dissociation is a "disruption of the usually integrated functions of consciousness, memory, identity or perception of the environment" according to DSM-5. It is commonly seen in psychiatric disorders including primary dissociative disorders, post-traumatic stress disorder, depression, and panic disorder. Dissociative phenomena are also described in the context of substance intoxication, sleep deprivation and medical illnesses including traumatic brain injury, migraines, and epilepsy. Patients with epilepsy have higher rates of dissociative experiences as measured on the Dissociative Experiences Scale compared to healthy controls. Ictal symptoms, especially in focal epilepsy of temporal lobe origin, may include dissociative-like experiences such as déjà vu/jamais vu, depersonalization, derealization and what has been described as a "dreamy state". These descriptions are common in the setting of seizures that originate from mesial temporal lobe epilepsy and may involve the amygdala and hippocampus. Other ictal dissociative phenomena include autoscopy and out of body experiences, which are thought to be due to disruptions in networks responsible for the integration of one's own body and extra-personal space and involve the temporoparietal junction and posterior insula. In this narrative review, we will summarize the updated literature on dissociative experiences in epilepsy, as well as dissociative experiences in functional seizures. Using a case example, we will review the differential diagnosis of dissociative symptoms. We will also review neurobiological underpinnings of dissociative symptoms across different diagnostic entities and discuss how ictal symptoms may shed light on the neurobiology of complex mental processes including the subjective nature of consciousness and self-identity.
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Affiliation(s)
- Maureen Cassady
- Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
| | - Gaston Baslet
- Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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Epilepsy, behavior, and consciousness. Epilepsy Behav 2022; 137:108700. [PMID: 36463057 DOI: 10.1016/j.yebeh.2022.108700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 04/04/2022] [Indexed: 12/05/2022]
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Ota K, Nishii T, Fujii K, Oishi Y, Onishi N, Ota K, Yokoyama H, Takasu A. Altered consciousness with transient abnormal signals in the hippocampus: A case report. SAGE Open Med Case Rep 2021; 9:2050313X211054644. [PMID: 34707870 PMCID: PMC8543701 DOI: 10.1177/2050313x211054644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 10/04/2021] [Indexed: 11/29/2022] Open
Abstract
Hippocampal infarction is relatively rare. Many different diseases can mimic hippocampal
infarction including transient global amnesia, Alzheimer’s disease, epilepsy,
encephalitis, and encephalopathies. An 89-year-old man was transported to our hospital for
altered consciousness. Diffusion-weighted magnetic resonance imaging revealed slightly
intense signals in the hippocampus with a mildly decreased apparent diffusion coefficient.
Serial magnetic resonance imaging revealed features of hippocampal infarction. Symptoms
and cognitive function gradually improved with rehabilitation, and he was transferred to a
rehabilitation facility on Hospital Day 38. Hippocampal infarction is rare in patients
with altered mental status, but should be considered when magnetic resonance imaging shows
findings suggestive of this condition. Other differential diseases should be ruled out by
serial magnetic resonance imaging and observation of the clinical course.
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Affiliation(s)
- Koshi Ota
- Department of Emergency Medicine, Osaka Medical College, Takatsuki, Japan
| | - Tomonobu Nishii
- Department of Emergency Medicine, Osaka Medical College, Takatsuki, Japan
| | - Kensuke Fujii
- Department of Emergency Medicine, Osaka Medical College, Takatsuki, Japan
| | - Yasuo Oishi
- Department of Emergency Medicine, Osaka Medical College, Takatsuki, Japan
| | - Naoya Onishi
- Department of Emergency Medicine, Osaka Medical College, Takatsuki, Japan
| | - Kanna Ota
- Department of Emergency Medicine, Osaka Medical College, Takatsuki, Japan
| | - Hiroki Yokoyama
- Department of Emergency Medicine, Osaka Medical College, Takatsuki, Japan
| | - Akira Takasu
- Department of Emergency Medicine, Osaka Medical College, Takatsuki, Japan
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Nani A, Manuello J, Mancuso L, Liloia D, Costa T, Cauda F. The Neural Correlates of Consciousness and Attention: Two Sister Processes of the Brain. Front Neurosci 2019; 13:1169. [PMID: 31749675 PMCID: PMC6842945 DOI: 10.3389/fnins.2019.01169] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 10/16/2019] [Indexed: 12/30/2022] Open
Abstract
During the last three decades our understanding of the brain processes underlying consciousness and attention has significantly improved, mainly because of the advances in functional neuroimaging techniques. Still, caution is needed for the correct interpretation of these empirical findings, as both research and theoretical proposals are hampered by a number of conceptual difficulties. We review some of the most significant theoretical issues concerning the concepts of consciousness and attention in the neuroscientific literature, and put forward the implications of these reflections for a coherent model of the neural correlates of these brain functions. Even though consciousness and attention have an overlapping pattern of neural activity, they should be considered as essentially separate brain processes. The contents of phenomenal consciousness are supposed to be associated with the activity of multiple synchronized networks in the temporo-parietal-occipital areas. Only subsequently, attention, supported by fronto-parietal networks, enters the process of consciousness to provide focal awareness of specific features of reality.
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Affiliation(s)
- Andrea Nani
- Focus Lab, Department of Psychology, University of Turin, Turin, Italy
- GCS-FMRI, Koelliker Hospital and Department of Psychology, University of Turin, Turin, Italy
| | - Jordi Manuello
- Focus Lab, Department of Psychology, University of Turin, Turin, Italy
- GCS-FMRI, Koelliker Hospital and Department of Psychology, University of Turin, Turin, Italy
| | - Lorenzo Mancuso
- Focus Lab, Department of Psychology, University of Turin, Turin, Italy
- GCS-FMRI, Koelliker Hospital and Department of Psychology, University of Turin, Turin, Italy
| | - Donato Liloia
- Focus Lab, Department of Psychology, University of Turin, Turin, Italy
- GCS-FMRI, Koelliker Hospital and Department of Psychology, University of Turin, Turin, Italy
| | - Tommaso Costa
- Focus Lab, Department of Psychology, University of Turin, Turin, Italy
- GCS-FMRI, Koelliker Hospital and Department of Psychology, University of Turin, Turin, Italy
- Neuroscience Institute of Turin, University of Turin, Turin, Italy
| | - Franco Cauda
- Focus Lab, Department of Psychology, University of Turin, Turin, Italy
- GCS-FMRI, Koelliker Hospital and Department of Psychology, University of Turin, Turin, Italy
- Neuroscience Institute of Turin, University of Turin, Turin, Italy
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Kinney MO, Kovac S, Diehl B. Structured testing during seizures: A practical guide for assessing and interpreting ictal and postictal signs during video EEG long term monitoring. Seizure 2019; 72:13-22. [PMID: 31546090 DOI: 10.1016/j.seizure.2019.08.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Revised: 08/01/2019] [Accepted: 08/17/2019] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Ictal and postictal testing carried out in long-term epilepsy monitoring units is often sub-optimal. Recently, a European consensus protocol for testing patients during and after seizures was developed by a joint taskforce of the International League Against Epilepsy - Commission on European Affairs and the European Epilepsy Monitoring Unit Association. AIM Using this recently developed standardised assessment battery as a framework, the goal of this narrative review is to outline the proposed testing procedure in detail and explain the rationale for each individual component, focusing on the underlying neurobiology. This is intended to serve as an educational resource for staff working in epilepsy monitoring units. METHODS A literature review of PubMed was performed; using the search terms "seizure", "ictal", "postictal", "testing", "examination", and "interview". Relevant literature was reviewed and relevant references were chosen. The work is presented as a narrative review. RESULTS The proposed standardised assessment battery provides a comprehensive and user-friendly format for ictal-postictal testing, and examines consciousness, language, motor, sensory, and visual function. CONCLUSION The standardised approach proposed has the potential to make full use of data recorded during video EEG increasing the diagnostic yield with regards to lateralisation and localisation, aiding both presurgical and diagnostic studies.
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Affiliation(s)
- Michael Owen Kinney
- Department of Clinical Neurophysiology, National Hospital for Neurology and Neurosurgery, Queen Square, London, UK.
| | - Stjepana Kovac
- Department of Neurology, University of Münster, Münster, Germany
| | - Beate Diehl
- Department of Clinical Neurophysiology, National Hospital for Neurology and Neurosurgery, Queen Square, London, UK; Department of Clinical and Experimental Epilepsy, National Hospital for Neurology and Neurosurgery, Queen Square, London, UK
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Xie F, Xing W, Wang X, Liao W, Shi W. Altered states of consciousness in epilepsy: a DTI study of the brain. Int J Neurosci 2016; 127:667-672. [PMID: 27575403 DOI: 10.1080/00207454.2016.1229668] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Fangfang Xie
- Department of Radiology, Xiangya Hospital Central South University, Changsha, China
| | - Wu Xing
- Department of Radiology, Xiangya Hospital Central South University, Changsha, China
| | - Xiaoyi Wang
- Department of Radiology, Xiangya Hospital Central South University, Changsha, China
| | - Weihua Liao
- Department of Radiology, Xiangya Hospital Central South University, Changsha, China
| | - Wei Shi
- Department of Radiology, Xiangya Hospital Central South University, Changsha, China
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Campora N, Kochen S. Subjective and objective characteristics of altered consciousness during epileptic seizures. Epilepsy Behav 2016; 55:128-32. [PMID: 26773683 DOI: 10.1016/j.yebeh.2015.12.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 11/28/2015] [Accepted: 12/02/2015] [Indexed: 11/27/2022]
Abstract
BACKGROUND Conscious states are inner states and processes of awareness. These states are by definition subjective. METHODS We analyzed subjective and objective characteristics of alteration of consciousness (AOC) during epileptic seizures, including its involvement in both the level of awareness and subjective content of consciousness. We evaluated AOC using the Consciousness Seizure Scale, the Ictal Consciousness Inventory, and a new structured survey developed by our group: the Seizure Perception Survey, which incorporates patients' subjective experiences before and after they watch a video-electroencephalographic recording of their own seizure. RESULTS We included 35 patients (105 seizures) with drug-resistant epilepsy. Most seizures caused profound AOC. The content of consciousness was lower during temporal seizures with profound AOC. We uncovered a correlation between the subjective perception and objective duration of a seizure using the Seizure Perception Survey regarding memory; the patients had a better recall of ictal onset during wakefulness regardless of the epileptogenic zone, laterality, or magnitude of AOC. Nonetheless, the recovery of memory at the end of a seizure took more time in patients who showed greater AOC, less vivid content of consciousness, or a longer seizure. For 85% of the patients, this was the first time they were able to view their own seizures. The majority of the patients requested to view them again because this procedure allowed them to compare the recordings with their own memories and emotions during a seizure and to verify the real duration of the seizure. DISCUSSION Alteration of consciousness is one of the most dramatic clinical manifestations of epilepsy. Usually, practitioners or relatives assume that the patients with AOC may not have any knowledge on their seizures. In this study, however, we found that most patients with AOC had a fairly accurate perception of the duration of a seizure and retained their memory of ictal onset. In contrast, for the majority of the patients, watching their own seizure was an extremely positive experience, and most patients stated that they were surprised as well as glad to view what really happened, without expressing negative opinions. Inclusion of subjective characteristics of AOC into the analysis yielded complete assessment of various dimensions of consciousness and therefore allowed us to gain a more detailed understanding of consciousness.
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Affiliation(s)
- Nuria Campora
- Epilepsy Center, Ramos Mejía Hospital, Buenos Aires, Argentina; IBCN, CONICET, Buenos Aires University, Argentina; Epilepsy Center, El Cruce Hospital, Florencio Varela, Argentina.
| | - Silvia Kochen
- Epilepsy Center, Ramos Mejía Hospital, Buenos Aires, Argentina; IBCN, CONICET, Buenos Aires University, Argentina; Epilepsy Center, El Cruce Hospital, Florencio Varela, Argentina
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Chen WC, Chen EY, Gebre RZ, Johnson MR, Li N, Vitkovskiy P, Blumenfeld H. Epilepsy and driving: potential impact of transient impaired consciousness. Epilepsy Behav 2014; 30:50-7. [PMID: 24436967 PMCID: PMC4098969 DOI: 10.1016/j.yebeh.2013.09.024] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Driving is an important part of everyday life for most adults, and restrictions on driving can place a significant burden on individuals diagnosed with epilepsy. Although sensorimotor deficits during seizures may impair driving, decreased level of consciousness often has a more global effect on patients' ability to respond appropriately to the environment. Better understanding of the mechanisms underlying alteration of consciousness in epilepsy is important for decision-making by people with epilepsy, their physicians, and regulators in regard to the question of fitness to drive. Retrospective cohort and cross-sectional studies based on surveys or crash records can provide valuable information about driving in epilepsy. However, prospective objective testing of ictal driving ability during different types of seizures is needed to more fully understand the role of impaired consciousness and other deficits in disrupting driving. Driving simulators adapted for use in the epilepsy video-EEG monitoring unit may be well suited to provide both ictal and interictal data in patients with epilepsy. Objective information about impaired driving in specific types of epilepsy and seizures can provide better informed recommendations regarding fitness to drive, potentially improving the quality of life of people living with epilepsy.
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Affiliation(s)
- William C. Chen
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Eric Y. Chen
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Rahiwa Z. Gebre
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Michelle R. Johnson
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Ningcheng Li
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Petr Vitkovskiy
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Hal Blumenfeld
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA,Department of Neurobiology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA,Department of Neurosurgery, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
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Hanoğlu L, Özkara Ç, Yalçiner B, Nani A, Cavanna AE. Epileptic qualia and self-awareness: a third dimension for consciousness. Epilepsy Behav 2014; 30:62-5. [PMID: 24100248 DOI: 10.1016/j.yebeh.2013.09.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Accepted: 09/05/2013] [Indexed: 11/18/2022]
Abstract
Over the last few decades, there has been increasing awareness among epileptologists about the need to refine our understanding and assessment of ictal consciousness, focusing on both subjective and behavioral aspects of seizures. Specifically, there have been suggestions that both the internal and external milieux - the former related to the phenomenal qualia of experience, the latter related to behavior - must be taken into account for a better understanding of altered states of consciousness in epilepsy. It has been proposed that clinical and experimental data from patients experiencing alterations of consciousness during epileptic seizures could be better understood within a bidimensional model, in which any manifestation of conscious experience can be plotted according to the level and contents of consciousness. The 'level' axis measures the degree of alertness/arousal, whereas the 'contents' axis measures the vividness of specific experiential phenomena reported by the patient. We argue that certain seizure types might require more rigorous conceptual models for their characterization, and we highlight the potential usefulness of a more refined framework which includes a further dimension related to the 'self', in addition to those of 'level' and 'contents'. This model could be visualized in a three-dimensional space to allow fine-grained distinctions between epileptic seizures.
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Affiliation(s)
- Lütfü Hanoğlu
- Department of Neurology, Medical Faculty, Medipol University, Istanbul, Turkey
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Video-electroencephalography investigation of ictal alterations of consciousness in epilepsy and nonepileptic attack disorder: practical considerations. Epilepsy Behav 2014; 30:24-7. [PMID: 24113568 DOI: 10.1016/j.yebeh.2013.09.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2013] [Accepted: 09/04/2013] [Indexed: 11/24/2022]
Abstract
The ictal assessment of consciousness is of central importance in the differential diagnosis of epilepsy and nonepileptic attack disorder (NEAD). Long-term video-electroencephalography (video-EEG) is currently considered the gold standard investigative technique for the evaluation of patients with recurrent attacks associated with transient alterations of arousal (responsiveness) and/or awareness (experiential states). This paper offers a concise review focusing on the practical aspects of clinical relevance in the video-EEG diagnostic workout of inpatients with suspected epilepsy or NEAD, as outlined in existing guidelines and recommendations. The reviewed literature implies that both implementation of specific procedures (e.g., activation maneuvers) and interpersonal approach (e.g., monitoring protocols) during video-EEG should be tailored to the individual patient's presentation.
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Nani A, Cavanna AE. The quantitative measurement of consciousness during epileptic seizures. Epilepsy Behav 2014; 30:2-5. [PMID: 24113569 DOI: 10.1016/j.yebeh.2013.09.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2013] [Accepted: 09/04/2013] [Indexed: 11/16/2022]
Abstract
The assessment of consciousness is a fundamental element in the classification of epileptic seizures. It is, therefore, of great importance for clinical practice to develop instruments that enable an accurate and reliable measurement of the alteration of consciousness during seizures. Over the last few years, three psychometric scales have been specifically proposed to measure ictal consciousness: the Ictal Consciousness Inventory (ICI), the Consciousness Seizure Scale (CSS), and the Responsiveness in Epilepsy Scale--versions I and II (RES-I and RES-II). The ICI is a self-report psychometric instrument which retrospectively assesses ictal consciousness along the dimensions of the level/arousal and contents/awareness. The CSS has been used by clinicians to quantify the impairment of consciousness in order to establish correlations with the brain mechanisms underlying alterations of consciousness during temporal lobe seizures. The most recently developed observer-rated instrument is the RES-I, which has been used to assess responsiveness during epileptic seizures in patients undergoing video-EEG. The implementation of standardized psychometric tools for the assessment of ictal consciousness can complement clinical observations and contribute to improve accuracy in seizure classification.
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Affiliation(s)
- Andrea Nani
- Michael Trimble Neuropsychiatry Research Group, BSMHFT, UK; Section of Neuropharmacology and Neurobiology, School of Clinical and Experimental Medicine, University of Birmingham, UK
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Rektor I, Schachter SC, Arzy S, Baloyannis SJ, Bazil C, Brázdil M, Engel J, Helmstaedter G, Hesdorffer DC, Jones-Gotman M, Kesner L, Komárek V, Krämer G, Leppik IE, Mann MW, Mula M, Risse GL, Stoker GW, Kasteleijn-Nolst Trenité DGA, Trimble M, Tyrliková I, Korczyn AD. Epilepsy, behavior, and art (Epilepsy, Brain, and Mind, part 1). Epilepsy Behav 2013; 28:261-82. [PMID: 23764495 DOI: 10.1016/j.yebeh.2013.03.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/28/2013] [Indexed: 01/22/2023]
Abstract
Epilepsy is both a disease of the brain and the mind. Brain diseases, structural and/or functional, underlie the appearance of epilepsy, but the notion of epilepsy is larger and cannot be reduced exclusively to the brain. We can therefore look at epilepsy from two angles. The first perspective is intrinsic: the etiology and pathophysiology, problems of therapy, impact on the brain networks, and the "mind" aspects of brain functions - cognitive, emotional, and affective. The second perspective is extrinsic: the social interactions of the person with epilepsy, the influence of the surrounding environment, and the influences of epilepsy on society. All these aspects reaching far beyond the pure biological nature of epilepsy have been the topics of two International Congresses of Epilepsy, Brain, and Mind that were held in Prague, Czech Republic, in 2010 and 2012 (the third Congress will be held in Brno, Czech Republic on April 3-5, 2014; www.epilepsy-brain-mind2014.eu). Here, we present the first of two papers with extended summaries of selected presentations of the 2012 Congress that focused on epilepsy, behavior, and art.
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Affiliation(s)
- Ivan Rektor
- Masaryk University, Brno Epilepsy Center, St. Anne's Hospital and School of Medicine, and Central European Institute of Technology (CEITEC), Brno, Czech Republic
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De Sousa A. Towards an integrative theory of consciousness: part 1 (neurobiological and cognitive models). Mens Sana Monogr 2013; 11:100-50. [PMID: 23678241 PMCID: PMC3653219 DOI: 10.4103/0973-1229.109335] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 12/13/2012] [Accepted: 12/15/2012] [Indexed: 12/22/2022] Open
Abstract
The study of consciousness is poised today at interesting crossroads. There has been a surge of research into various neurobiological underpinnings of consciousness in the past decade. The present article looks at the theories regarding this complex phenomenon, especially the ones that neurobiology, cognitive neuroscience and cognitive psychology have to offer. We will first discuss the origin and etymology of word consciousness and its usage. Neurobiological correlates of consciousness are discussed with structures like the ascending reticular activating system, the amygdala, the cerebellum, the thalamus, the frontoparietal circuits, the prefrontal cortex and the precuneus. The cellular and microlevel theories of consciousness and cerebral activity at the neuronal level contributing to consciousness are highlighted, along with the various theories posited in this area. The role of neuronal assemblies and circuits along with firing patterns and their ramifications for the understanding of consciousness are discussed. A section on the role of anaesthesia and its links to consciousness is presented, along with details of split-brain studies in consciousness and altered states of awareness, including the vegetative states. The article finally discusses the progress cognitive psychology has made in identifying and theorising various perspectives of consciousness, perceptual awareness and conscious processing. Both recent and past researches are highlighted. The importance and salient features of each theory are discussed along with the pitfalls, if present. A need for integration of various theories to understand consciousness from a holistic perspective is stressed, to enable one to reach a theory that explains the ultimate neurobiology of consciousness.
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Bagshaw AP, Cavanna AE. Resting state networks in paroxysmal disorders of consciousness. Epilepsy Behav 2013; 26:290-4. [PMID: 23089152 DOI: 10.1016/j.yebeh.2012.09.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Accepted: 09/06/2012] [Indexed: 10/27/2022]
Abstract
Functional MRI (fMRI) has transformed academic neuroscience in the last decade and is now the most widely used non-invasive functional brain imaging technique. However, it has had much less of an impact in clinical neuroscience. While a majority of fMRI applications examine brain function in response to an externally driven task, an alternative approach characterizes the brain's intrinsic functional architecture. This involves fMRI scanning in the absence of an explicit task (i.e., in the resting state) and is, therefore, much more easily performed and tolerated by neurological and neuropsychiatric patient groups. The data are easily acquired, and the functional networks extracted are reproducible and reliable. However, quantifying networks of distributed brain activity and identifying the most informative features in a particular disorder remain a challenge. Progress has been made in this direction in recent years, with the adoption of mathematical tools from communications engineering. Specific alterations to the brain's functional connectivity at rest have been observed in generalized and focal epilepsies, as well as in non-epileptic attack disorder. The challenge for the future is to exploit knowledge of how the brain works as a complex system in order to develop more accurate and sensitive diagnostic tests for neurological and neuropsychiatric disorders.
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Alvarez-Silva S, Alvarez-Rodriguez J, Cavanna AE. Epileptic aura and qualitative alterations of consciousness in focal seizures: a neuropsychiatric approach. Epilepsy Behav 2012; 23:512-3. [PMID: 22405861 DOI: 10.1016/j.yebeh.2011.11.031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2011] [Accepted: 11/25/2011] [Indexed: 11/20/2022]
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Cavanna AE, Rickards H, Ali F. What makes a simple partial seizure complex? Epilepsy Behav 2011; 22:651-8. [PMID: 22079438 DOI: 10.1016/j.yebeh.2011.10.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Accepted: 10/02/2011] [Indexed: 11/24/2022]
Abstract
The assessment of ictal consciousness has been the landmark criterion for the differentiation between simple and complex partial seizures over the last three decades. After review of the historical development of the concept of "complex partial seizure," the difficulties surrounding the simple versus complex dichotomy are addressed from theoretical, phenomenological, and neurophysiological standpoints. With respect to consciousness, careful analysis of ictal semiology shows that both the general level of vigilance and the specific contents of the conscious state can be selectively involved during partial seizures. Moreover, recent neuroimaging findings, coupled with classic electrophysiological studies, suggest that the neural substrate of ictal alterations of consciousness is twofold: focal hyperactivity in the limbic structures generates the complex psychic phenomena responsible for the altered contents of consciousness, and secondary disruption of the network involving the thalamus and the frontoparietal association cortices affects the level of awareness. These data, along with the localization information they provide, should be taken into account in the formulation of new criteria for the classification of seizures with focal onset.
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Affiliation(s)
- Andrea E Cavanna
- The Michael Trimble Neuropsychiatry Research Group, Department of Neuropsychiatry, University of Birmingham and BSMHFT, Birmingham, UK.
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Abstract
Monaco F, Mula M, Cavanna AE. The neurophilosophy of epileptic experiences.Background:Specific alterations of consciousness have a central role in the phenomenological description of epileptic seizures and in the patient's subjective reports.Methods:This article discusses the use of philosophical methodology within a neurological framework to understand consciousness.Results:How the alterations in consciousness are experienced by patients with epilepsy depends largely on the localization of the underlying neurophysiological dysfuntion.Discussion:Rigorous conceptual analysis of ictal experience reports can help to illuminate the study of consciousness.
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Affiliation(s)
- Francesco Monaco
- Department of Neurology, Amedeo Avogadro University, Novara, Italy
| | - Marco Mula
- Department of Neurology, Amedeo Avogadro University, Novara, Italy
| | - Andrea E Cavanna
- Department of Neuropsychiatry, Birmingham and Solihull Mental Health NHS Foundation Trust, University of Birmingham, Birmingham, UK
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Monaco F, Mula M. Cesare Lombroso and epilepsy 100 years later: An unabridged report of his original transactions. Epilepsia 2011; 52:679-88. [DOI: 10.1111/j.1528-1167.2010.02959.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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21
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Monaco F, Servo S, Cavanna AE. Famous people with Gilles de la Tourette syndrome? J Psychosom Res 2009; 67:485-90. [PMID: 19913652 DOI: 10.1016/j.jpsychores.2009.07.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 06/27/2009] [Accepted: 07/07/2009] [Indexed: 11/26/2022]
Abstract
Virtually no neurologist nor psychiatrist today can be unaware of the diagnosis of Gilles de la Tourette syndrome (GTS). Although the eponymous description by Dr. Georges Gilles de la Tourette was published in 1885, familiarity with this syndrome has been achieved only recently. In this article, the two most renown accounts of exceptional individuals retrospectively diagnosed with GTS are critically analyzed: British lexicographer Samuel Johnson and Austrian musician Wolfgang Amadeus Mozart. In both cases, clinical descriptions have been retrieved from written documents predating Gilles de la Tourette's original publication. The case for Samuel Johnson having GTS is strong, mainly based on Boswell's extensive biographical account. Johnson was reported to have a great range of tics and compulsions, including involuntary utterances, repetitive ejaculations, and echo-phenomena. On the other hand, there is circumstantial evidence that Mozart may have had hyperactivity, restlessness, sudden impulses, odd motor behaviors, echo/palilalia, love of nonsense words, and scatology, the latter being documented in autograph letters ("coprographia"). However, the evidence supporting the core features of GTS, i.e., motor and vocal tics, is rather inconsistent. Thus, GTS seems to be an implausible diagnosis in Mozart's medical history and completely unrelated to his undisputed musical genius.
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Affiliation(s)
- Francesco Monaco
- Department of Neurology, Amedeo Avogadro University, Novara, Italy
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Long JJ, Shen B, Luo T, Stewart L, McMurran TJ, Leung LS. Pilocarpine model of temporal lobe epilepsy shows enhanced response to general anesthetics. Exp Neurol 2009; 219:308-18. [DOI: 10.1016/j.expneurol.2009.05.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Revised: 05/23/2009] [Accepted: 05/28/2009] [Indexed: 10/20/2022]
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Arthuis M, Valton L, Régis J, Chauvel P, Wendling F, Naccache L, Bernard C, Bartolomei F. Impaired consciousness during temporal lobe seizures is related to increased long-distance cortical-subcortical synchronization. ACTA ACUST UNITED AC 2009; 132:2091-101. [PMID: 19416952 DOI: 10.1093/brain/awp086] [Citation(s) in RCA: 148] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Loss of consciousness (LOC) is a dramatic clinical manifestation of temporal lobe seizures. Its underlying mechanism could involve altered coordinated neuronal activity between the brain regions that support conscious information processing. The consciousness access hypothesis assumes the existence of a global workspace in which information becomes available via synchronized activity within neuronal modules, often widely distributed throughout the brain. Re-entry loops and, in particular, thalamo-cortical communication would be crucial to functionally bind different modules together. In the present investigation, we used intracranial recordings of cortical and subcortical structures in 12 patients, with intractable temporal lobe epilepsy (TLE), as part of their presurgical evaluation to investigate the relationship between states of consciousness and neuronal activity within the brain. The synchronization of electroencephalography signals between distant regions was estimated as a function of time by using non-linear regression analysis. We report that LOC occurring during temporal lobe seizures is characterized by increased long-distance synchronization between structures that are critical in processing awareness, including thalamus (Th) and parietal cortices. The degree of LOC was found to correlate with the amount of synchronization in thalamo-cortical systems. We suggest that excessive synchronization overloads the structures involved in consciousness processing, preventing them from treating incoming information, thus resulting in LOC.
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Affiliation(s)
- Marie Arthuis
- INSERM, U751, Laboratoire de Neurophysiologie et Neuropsychologie, Marseille, F-13005, France
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Alterations in the contents of consciousness in partial epileptic seizures. Epilepsy Behav 2008; 13:366-71. [PMID: 18522873 DOI: 10.1016/j.yebeh.2008.04.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2008] [Revised: 04/15/2008] [Accepted: 04/18/2008] [Indexed: 11/20/2022]
Abstract
Epilepsy research suffers from a deficiency of systematic studies concerning the phenomenology of the contents of consciousness during seizures, partially because of the lack of suitable research methods. The Phenomenology of Consciousness Inventory (PCI), a standardized, valid, and reliable questionnaire, was used here to study which dimensions of the contents of consciousness are distorted during partial epileptic seizures compared with baseline. Further, the similarity of the altered pattern of subjective experiences across recurring seizures was also explored. Our results indicate that patients with epilepsy report alterations on most dimensions of the contents of consciousness in conjunction with seizures, but individual seizure experiences remain similar from one seizure to another. The PCI was found suitable for the assessment of subjective experiences during epileptic seizures and could be a valuable tool in providing new information about phenomenal consciousness in epilepsy in both the research and clinical settings.
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Cavanna AE, Mula M, Servo S, Strigaro G, Tota G, Barbagli D, Collimedaglia L, Viana M, Cantello R, Monaco F. Measuring the level and content of consciousness during epileptic seizures: the Ictal Consciousness Inventory. Epilepsy Behav 2008; 13:184-8. [PMID: 18353730 DOI: 10.1016/j.yebeh.2008.01.009] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2007] [Revised: 01/14/2008] [Accepted: 01/15/2008] [Indexed: 01/21/2023]
Abstract
Ictal alterations of the level of general awareness and subjective content of consciousness play a pivotal role in the clinical phenomenology of epilepsy, and reflect the pathological involvement of different neurobiological substrates. However, no self-reported measures have been proposed for patients experiencing altered conscious states during seizures. This study describes the development and validation of a new scale for the quantitative assessment of the level and content of ictal consciousness, the Ictal Consciousness Inventory (ICI). The ICI is a 20-item questionnaire generated on the basis of interviews with patients, literature review, and consultation with experts. It was tested on a sample of 110 patients attending three different epilepsy clinics in Northern Italy, who also completed standardized clinical scales. Standard psychometric methods were used to demonstrate that this scale satisfies criteria for acceptability, reliability, and validity. The ICI is proposed as a user-friendly and clinically sound instrument for the measurement of ictal alterations of consciousness in patients with epilepsy.
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Affiliation(s)
- A E Cavanna
- Department of Neurology, Amedeo Avogadro University, Novara, Italy.
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LaFrance WC, Gates JR, Trimble MR. Psychogenic unresponsiveness and nonepileptic seizures. HANDBOOK OF CLINICAL NEUROLOGY 2008; 90:317-328. [PMID: 18631831 DOI: 10.1016/s0072-9752(07)01718-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Affiliation(s)
- W Curt LaFrance
- Brown Medical School and Rhode Island Hospital, Providence, RI, USA.
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Johanson M, Valli K, Revonsuo A, Wedlund JE. Content analysis of subjective experiences in partial epileptic seizures. Epilepsy Behav 2008; 12:170-82. [PMID: 18086461 DOI: 10.1016/j.yebeh.2007.10.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2007] [Revised: 10/02/2007] [Accepted: 10/03/2007] [Indexed: 11/30/2022]
Abstract
A new content analysis method for systematically describing the phenomenology of subjective experiences in connection with partial epileptic seizures is described. Forty patients provided 262 descriptions of subjective experience relative to their partial epileptic seizures. The results revealed that subjective experiences during seizures consist mostly of sensory and bodily sensations, hallucinatory experiences, and thinking. The majority of subjective experiences during seizures are bizarre and distorted; nevertheless, the patients are able to engage in adequate behavior. To the best of our knowledge, this is the first study for which detailed subjective seizure descriptions were collected immediately after each seizure and the first study in which the content of verbal reports of subjective experiences during seizures, including both the ictal and postictal experiences, has been analyzed in detail.
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Affiliation(s)
- Mirja Johanson
- Neurological Rehabilitation Clinic, Stora Sköndal Foundation, 128 85 Sköndal, Sweden.
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Abstract
This article reviews the rapidly growing literature on the functional anatomy and behavioral correlates of the precuneus, with special reference to imaging neuroscience studies using hamodynamic techniques. The precuneus, along with adjacent areas within the posteromedial parietal cortex, is among the most active cortical regions according to the "default mode" of brain function during the conscious resting state, whereas it selectively deactivates in a number of pathophysiological conditions (ie, sleep, vegetative state, drug-induced anesthesia), and neuropsychiatric disorders (ie, epilepsy, Alzheimer's disease, and schizophrenia) characterized by impaired consciousness. These findings, along with the widespread connectivity pattern, suggest that the precuneus may play a central role in the neural network correlates of consciousness. Specifically, its activity seems to correlate with self-reflection processes, possibly involving mental imagery and episodic/autobiographical memory retrieval.
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Alvarez-Silva S, Alvarez-Silva I, Alvarez-Rodriguez J, Perez-Echeverria MJ, Campayo-Martinez A, Rodriguez-Fernandez FL. Epileptic consciousness: concept and meaning of aura. Epilepsy Behav 2006; 8:527-33. [PMID: 16510316 DOI: 10.1016/j.yebeh.2005.12.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2005] [Revised: 12/15/2005] [Accepted: 12/21/2005] [Indexed: 10/25/2022]
Abstract
This research is based on previous publications that have analyzed certain neuropsychological phenomena that always have the same characteristic clinical features: a vivid experience of sudden onset and automatic development, accompanied by an intense sensation of strangeness. When these automatisms are accompanied by only mental symptoms, the designation paroxysmal psychic automatisms (PPAs) is proposed, and they should be interpreted as partial seizures (PSs) with a psychic content whenever they clearly exhibit the four features of suddenness, passivity, intensity, and strangeness. This interpretation is based on the existence of a wealth of scientific literature indicating an overlap between PPAs and PSs; moreover, bibliographic reviews indicate that the clinical signs just defined as characterizing PPAs are precisely those defining the epileptic consciousness.
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