Biomaterial Database

Subcortical structures and pathways involved in convulsive seizure generation. 1992

K Gale

Department of Pharmacology, Georgetown University Medical Center, Washington, DC 20007.

Convulsive seizures in animal models usually involve one or more of the following components: (1) limbic motor seizures, (2) explosive running-bouncing clonic seizures, and (3) tonic extensor seizures. Each of these components depends on specific and experimentally separable anatomic substrates. Limbic motor seizures depend on forebrain structures for their initiation and propagation, with the prepiriform, piriform, and entorhinal cortices playing a prominent role in conjunction with hippocampus, amygdala, substantia innominata, and mediodorsal thalamus. In contrast, seizures involving running-bouncing clonus or tonic extension depend on neural substrates in the brainstem and do not appear to require the integrity of the forebrain for their development or expression. The inferior colliculus is a region from which running-bouncing seizures can be elicited by chemical or electrical stimulation. Tonic extensor seizures depend on the integrity of the nucleus reticularis pontis oralis, but a specific locus responsible for triggering these seizures has yet to be identified. Under conditions of chronic or repeated seizure activity over prolonged time periods, seizures evoked from the hindbrain can recruit forebrain circuits; conversely, repeated stimulation of forebrain limbic circuits (e.g., kindling) can modify susceptibility to brainstem convulsions. These long-term alterations may result from changes in the activity of seizure "gating" pathways, which are circuits that influence seizure susceptibility by modulating the threshold for the initiation and/or propagation of the seizures. In general, these pathways are not part of any core seizure propagation pathway per se. In many cases, the gating substrates are relatively nonselective as to the type of seizure they can influence. In this category, the substantia nigra and its related circuits within the basal ganglia serve a prominent role. In addition, ascending noradrenergic projections have been implicated in the regulation of seizure threshold. Other gating mechanisms involve thalamic circuitry and pathways originating in cerebellum.

UI	MeSH Term	Description	Entries
D009434	Neural Pathways	Neural tracts connecting one part of the nervous system with another.	Neural Interconnections,Interconnection, Neural,Interconnections, Neural,Neural Interconnection,Neural Pathway,Pathway, Neural,Pathways, Neural
D001921	Brain	The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.	Encephalon
D001931	Brain Mapping	Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.	Brain Electrical Activity Mapping,Functional Cerebral Localization,Topographic Brain Mapping,Brain Mapping, Topographic,Functional Cerebral Localizations,Mapping, Brain,Mapping, Topographic Brain
D002540	Cerebral Cortex	The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulci. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.	Allocortex,Archipallium,Cortex Cerebri,Cortical Plate,Paleocortex,Periallocortex,Allocortices,Archipalliums,Cerebral Cortices,Cortex Cerebrus,Cortex, Cerebral,Cortical Plates,Paleocortices,Periallocortices,Plate, Cortical
D004569	Electroencephalography	Recording of electric currents developed in the brain by means of electrodes applied to the scalp, to the surface of the brain, or placed within the substance of the brain.	EEG,Electroencephalogram,Electroencephalograms
D004827	Epilepsy	A disorder characterized by recurrent episodes of paroxysmal brain dysfunction due to a sudden, disorderly, and excessive neuronal discharge. Epilepsy classification systems are generally based upon: (1) clinical features of the seizure episodes (e.g., motor seizure), (2) etiology (e.g., post-traumatic), (3) anatomic site of seizure origin (e.g., frontal lobe seizure), (4) tendency to spread to other structures in the brain, and (5) temporal patterns (e.g., nocturnal epilepsy). (From Adams et al., Principles of Neurology, 6th ed, p313)	Aura,Awakening Epilepsy,Seizure Disorder,Epilepsy, Cryptogenic,Auras,Cryptogenic Epilepsies,Cryptogenic Epilepsy,Epilepsies,Epilepsies, Cryptogenic,Epilepsy, Awakening,Seizure Disorders
D005071	Evoked Potentials	Electrical responses recorded from nerve, muscle, SENSORY RECEPTOR, or area of the CENTRAL NERVOUS SYSTEM following stimulation. They range from less than a microvolt to several microvolts. The evoked potential can be auditory (EVOKED POTENTIALS, AUDITORY), somatosensory (EVOKED POTENTIALS, SOMATOSENSORY), visual (EVOKED POTENTIALS, VISUAL), or motor (EVOKED POTENTIALS, MOTOR), or other modalities that have been reported.	Event Related Potential,Event-Related Potentials,Evoked Potential,N100 Evoked Potential,P50 Evoked Potential,N1 Wave,N100 Evoked Potentials,N2 Wave,N200 Evoked Potentials,N3 Wave,N300 Evoked Potentials,N4 Wave,N400 Evoked Potentials,P2 Wave,P200 Evoked Potentials,P50 Evoked Potentials,P50 Wave,P600 Evoked Potentials,Potentials, Event-Related,Event Related Potentials,Event-Related Potential,Evoked Potential, N100,Evoked Potential, N200,Evoked Potential, N300,Evoked Potential, N400,Evoked Potential, P200,Evoked Potential, P50,Evoked Potential, P600,Evoked Potentials, N100,Evoked Potentials, N200,Evoked Potentials, N300,Evoked Potentials, N400,Evoked Potentials, P200,Evoked Potentials, P50,Evoked Potentials, P600,N1 Waves,N2 Waves,N200 Evoked Potential,N3 Waves,N300 Evoked Potential,N4 Waves,N400 Evoked Potential,P2 Waves,P200 Evoked Potential,P50 Waves,P600 Evoked Potential,Potential, Event Related,Potential, Event-Related,Potential, Evoked,Potentials, Event Related,Potentials, Evoked,Potentials, N400 Evoked,Related Potential, Event,Related Potentials, Event,Wave, N1,Wave, N2,Wave, N3,Wave, N4,Wave, P2,Wave, P50,Waves, N1,Waves, N2,Waves, N3,Waves, N4,Waves, P2,Waves, P50
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012640	Seizures	Clinical or subclinical disturbances of cortical function due to a sudden, abnormal, excessive, and disorganized discharge of brain cells. Clinical manifestations include abnormal motor, sensory and psychic phenomena. Recurrent seizures are usually referred to as EPILEPSY or "seizure disorder."	Absence Seizure,Absence Seizures,Atonic Absence Seizure,Atonic Seizure,Clonic Seizure,Complex Partial Seizure,Convulsion,Convulsions,Convulsive Seizure,Convulsive Seizures,Epileptic Seizure,Epileptic Seizures,Generalized Absence Seizure,Generalized Tonic-Clonic Seizures,Jacksonian Seizure,Myoclonic Seizure,Non-Epileptic Seizure,Nonepileptic Seizure,Partial Seizure,Seizure,Seizures, Convulsive,Seizures, Focal,Seizures, Generalized,Seizures, Motor,Seizures, Sensory,Tonic Clonic Seizure,Tonic Seizure,Tonic-Clonic Seizure,Atonic Absence Seizures,Atonic Seizures,Clonic Seizures,Complex Partial Seizures,Convulsion, Non-Epileptic,Generalized Absence Seizures,Myoclonic Seizures,Non-Epileptic Seizures,Nonepileptic Seizures,Partial Seizures,Petit Mal Convulsion,Seizures, Auditory,Seizures, Clonic,Seizures, Epileptic,Seizures, Gustatory,Seizures, Olfactory,Seizures, Somatosensory,Seizures, Tonic,Seizures, Tonic-Clonic,Seizures, Vertiginous,Seizures, Vestibular,Seizures, Visual,Single Seizure,Tonic Seizures,Tonic-Clonic Seizures,Absence Seizure, Atonic,Absence Seizure, Generalized,Absence Seizures, Atonic,Absence Seizures, Generalized,Auditory Seizure,Auditory Seizures,Clonic Seizure, Tonic,Clonic Seizures, Tonic,Convulsion, Non Epileptic,Convulsion, Petit Mal,Convulsions, Non-Epileptic,Focal Seizure,Focal Seizures,Generalized Seizure,Generalized Seizures,Generalized Tonic Clonic Seizures,Generalized Tonic-Clonic Seizure,Gustatory Seizure,Gustatory Seizures,Motor Seizure,Motor Seizures,Non Epileptic Seizure,Non Epileptic Seizures,Non-Epileptic Convulsion,Non-Epileptic Convulsions,Olfactory Seizure,Olfactory Seizures,Partial Seizure, Complex,Partial Seizures, Complex,Seizure, Absence,Seizure, Atonic,Seizure, Atonic Absence,Seizure, Auditory,Seizure, Clonic,Seizure, Complex Partial,Seizure, Convulsive,Seizure, Epileptic,Seizure, Focal,Seizure, Generalized,Seizure, Generalized Absence,Seizure, Generalized Tonic-Clonic,Seizure, Gustatory,Seizure, Jacksonian,Seizure, Motor,Seizure, Myoclonic,Seizure, Non-Epileptic,Seizure, Nonepileptic,Seizure, Olfactory,Seizure, Partial,Seizure, Sensory,Seizure, Single,Seizure, Somatosensory,Seizure, Tonic,Seizure, Tonic Clonic,Seizure, Tonic-Clonic,Seizure, Vertiginous,Seizure, Vestibular,Seizure, Visual,Seizures, Generalized Tonic-Clonic,Seizures, Nonepileptic,Sensory Seizure,Sensory Seizures,Single Seizures,Somatosensory Seizure,Somatosensory Seizures,Tonic Clonic Seizures,Tonic-Clonic Seizure, Generalized,Tonic-Clonic Seizures, Generalized,Vertiginous Seizure,Vertiginous Seizures,Vestibular Seizure,Vestibular Seizures,Visual Seizure,Visual Seizures