Epilepsy Excitation-Inhibition Imbalance Module

Neuroscience Module epilepsy_excitation_inhibition_imbalance 85 disorders Pathograph 5

A conserved network-hyperexcitability module representing the final common pathway of the epilepsies: a primary lesion in ion-channel function, synaptic transmission, or inhibitory circuitry shifts the balance of excitation and inhibition toward excitation, producing neuronal hyperexcitability and hypersynchronous firing that generate recurrent seizures. Genetic (channelopathy/synaptopathy), structural, metabolic, and acquired epilepsies differ in the upstream lesion but converge on excitation/inhibition (E/I) imbalance. Individual disorder entries declare conformance via conforms_to on their pathophysiology nodes, substituting the disorder-specific lesion (e.g., SCN1A loss in Dravet syndrome, GABA-receptor variant, mTOR-pathway malformation) while preserving the conserved E/I-imbalance-to-seizure chain.

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Pathophysiology Nodes

5 shared nodes are defined in this module.

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Cell Types

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Biological Processes

Notes

This is a mechanism module, not a specific disease. Disorder entries reference individual nodes via conforms_to (e.g., "epilepsy_excitation_inhibition_imbalance#Neuronal Hyperexcitability and Hypersynchrony"). Conforming nodes should substitute the disorder-specific driver of E/I imbalance: sodium/potassium/calcium channel variants in genetic channelopathies, GABAergic interneuron dysfunction, mTOR-pathway cortical malformations, or acquired network reorganization after injury. The E/I-balance framework is a useful paradigm but is acknowledged in the literature to be an incomplete account of all epilepsy mechanisms.

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Used By Disorder Entries

Alpers-Huttenlocher Syndrome via Selective Interneuron and Pyramidal Neuron Loss in Occipital Cortex → Excitation-Inhibition Imbalance , Intractable Focal Epilepsy and Epilepsia Partialis Continua → Recurrent Unprovoked Seizures

Autosomal Dominant Epilepsy with Auditory Features via Disrupted LGI1-ADAM22 Trans-Synaptic Complex → Ion Channel and Synaptic Dysfunction , Dysregulated AMPA Receptor Clustering and Synaptic Excitability → Excitation-Inhibition Imbalance , Lateral Temporal Cortical Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Focal Seizures with Auditory Features → Recurrent Unprovoked Seizures

Benign Neonatal Seizures via Kv7.2/Kv7.3 M-Channel Dysfunction → Ion Channel and Synaptic Dysfunction , Neonatal Neuronal Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Neonatal Focal Seizure Generation → Seizure Generation and Epileptogenesis

CACNA1E-Related Developmental and Epileptic Encephalopathy via Neuronal Hyperexcitability and Excitation-Inhibition Imbalance → Neuronal Hyperexcitability and Hypersynchrony

CDKL5 Deficiency Disorder via Disrupted Cortical Excitation-Inhibition Balance → Excitation-Inhibition Imbalance , Neuronal Network Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Early-Onset Intractable Epilepsy → Recurrent Unprovoked Seizures

CHD2-Related Developmental and Epileptic Encephalopathy via Cortical Network Hyperexcitability → Excitation-Inhibition Imbalance

Childhood Absence Epilepsy via Enhanced Thalamic T-type Calcium Current → Ion Channel and Synaptic Dysfunction , Abnormal Thalamocortical Oscillation and Hypersynchrony → Neuronal Hyperexcitability and Hypersynchrony , Absence Seizures → Recurrent Unprovoked Seizures

Childhood Occipital Visual Epilepsy via Occipital Interictal and Ictal Paroxysmal Discharges → Neuronal Hyperexcitability and Hypersynchrony , Recurrent Brief Diurnal Visual Seizures → Recurrent Unprovoked Seizures

CPLX1-Related Developmental and Epileptic Encephalopathy via Cortical Hyperexcitability and Seizures → Neuronal Hyperexcitability and Hypersynchrony

CYFIP2-Related Developmental and Epileptic Encephalopathy via Disrupted Synaptic and Dendritic Spine Remodeling → Ion Channel and Synaptic Dysfunction , Neuronal Network Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Drug-Resistant Epilepsy → Recurrent Unprovoked Seizures

DENND5A-Related Developmental and Epileptic Encephalopathy via Seizure Generation and Developmental and Epileptic Encephalopathy → Recurrent Unprovoked Seizures

DEPDC5-Related Epilepsy via Focal Cortical Hyperexcitability and Focal-Onset Seizures → Neuronal Hyperexcitability and Hypersynchrony

Developmental and Epileptic Encephalopathy 89 via Excitation-Inhibition Imbalance , Neuronal Hyperexcitability and Hypersynchrony , Early-Onset Epileptic Seizures → Recurrent Unprovoked Seizures

Developmental and Epileptic Encephalopathy with Spike-Wave Activation in Sleep via Abnormal Frequency-Dependent Cortical Excitability → Neuronal Hyperexcitability and Hypersynchrony , Focal and Atypical Absence Seizures → Recurrent Unprovoked Seizures

DNM1 Encephalopathy via Reduced Neurotransmission and Cortical Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony

Dravet_syndrome via SCN1A Gene Mutation → Ion Channel and Synaptic Dysfunction , Neuronal Hyperexcitability → Excitation-Inhibition Imbalance

Early-Infantile Developmental and Epileptic Encephalopathy via Reduced Kv7.2/Kv7.3 M-Current → Ion Channel and Synaptic Dysfunction , Increased Persistent Sodium Current → Ion Channel and Synaptic Dysfunction , Impaired Synaptic Vesicle Release and Inhibitory Circuit Formation → Ion Channel and Synaptic Dysfunction , Excitation-Inhibition Imbalance in Immature Cortical Networks → Excitation-Inhibition Imbalance , Burst-Suppression and Hypersynchronous Cortical Discharge → Neuronal Hyperexcitability and Hypersynchrony , Recurrent Drug-Resistant Seizures → Recurrent Unprovoked Seizures

Epilepsy via Neuronal Hyperexcitability → Excitation-Inhibition Imbalance

Epilepsy of Infancy with Migrating Focal Seizures via Increased Slack Sodium-Activated Potassium Current → Ion Channel and Synaptic Dysfunction , Multifocal Cortical Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Migrating Focal Seizure Generation → Recurrent Unprovoked Seizures

Epilepsy with Generalized Tonic-Clonic Seizures Alone via Polygenic Susceptibility to Generalized Epilepsy → Ion Channel and Synaptic Dysfunction , Cortico-Thalamocortical Excitation-Inhibition Imbalance → Excitation-Inhibition Imbalance , Generalized Hypersynchronous Discharge → Neuronal Hyperexcitability and Hypersynchrony , Recruitment of Motor Systems into Tonic-Clonic Output → Seizure Generation and Epileptogenesis , Recurrent Unprovoked Generalized Tonic-Clonic Seizures → Recurrent Unprovoked Seizures

Epilepsy with Myoclonic Absences via Hypersynchronous Three-Hertz Thalamocortical Spike-Wave Oscillation → Neuronal Hyperexcitability and Hypersynchrony , Rhythmic Myoclonus with Progressive Tonic Contraction → Recurrent Unprovoked Seizures

Epilepsy with Myoclonic-Atonic Seizures via Impaired GABA Transporter (GAT-1) Function → Ion Channel and Synaptic Dysfunction , Thalamocortical Network Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Myoclonic-Atonic and Generalized Seizures → Recurrent Unprovoked Seizures

Febrile Infection-Related Epilepsy Syndrome via Cytokine-Driven Lowering of Seizure Threshold → Ion Channel and Synaptic Dysfunction , Cortical Excitation-Inhibition Imbalance → Excitation-Inhibition Imbalance , Super-Refractory Status Epilepticus → Seizure Generation and Epileptogenesis , Chronic Drug-Resistant Epilepsy and Neurocognitive Sequelae → Recurrent Unprovoked Seizures

FGF12-Related Developmental and Epileptic Encephalopathy via Depolarizing Shift in Nav1.6 Fast Inactivation → Ion Channel and Synaptic Dysfunction , Increased Intrinsic Neuronal Excitability → Neuronal Hyperexcitability and Hypersynchrony , Epileptiform Network Activity → Seizure Generation and Epileptogenesis , Early-Onset Refractory Seizures → Recurrent Unprovoked Seizures

Focal Cortical Dysplasia Type II via Drug-Resistant Focal Epilepsy → Recurrent Unprovoked Seizures

GABRB3-Related Developmental and Epileptic Encephalopathy via GABRB3 Variant and Beta-3 Subunit Dysfunction → Ion Channel and Synaptic Dysfunction , Disrupted Excitation-Inhibition Balance in Developing Networks → Excitation-Inhibition Imbalance , Neuronal Hyperexcitability and Thalamocortical Hypersynchrony → Neuronal Hyperexcitability and Hypersynchrony , Seizure Generation and Developmental Encephalopathy → Seizure Generation and Epileptogenesis , Drug-Resistant Epilepsy with Developmental Impairment → Recurrent Unprovoked Seizures

GABRG2-Related Epilepsy via GABRG2 Variant and Gamma-2 Subunit Dysfunction → Ion Channel and Synaptic Dysfunction , Excitation-Inhibition Imbalance , Neuronal Hyperexcitability and Hypersynchrony

Genetic Developmental and Epileptic Encephalopathy via Neuronal Excitation-Inhibition Imbalance → Excitation-Inhibition Imbalance , Hypersynchronous Network Activity and Seizures → Neuronal Hyperexcitability and Hypersynchrony

GLUT1 Deficiency Syndrome via Neuronal Hyperexcitability and Hypersynchrony , Recurrent Pharmacoresistant Seizures → Recurrent Unprovoked Seizures

GNAO1-Related Developmental and Epileptic Encephalopathy via Impaired Gbg Modulation of Presynaptic Calcium Channels → Ion Channel and Synaptic Dysfunction , Cortical Excitation-Inhibition Imbalance → Excitation-Inhibition Imbalance , Developmental and Epileptic Encephalopathy → Recurrent Unprovoked Seizures

GRIN1-Related Neurodevelopmental Disorder via Disrupted Excitatory Neurotransmission and E/I Imbalance → Excitation-Inhibition Imbalance

GRIN2A-Related Epileptic Encephalopathy and Intellectual Disability via Cortical Excitation-Inhibition Imbalance and Network Hyperexcitability → Excitation-Inhibition Imbalance

GRIN2B-Related Developmental and Epileptic Encephalopathy via Cortical Excitation-Inhibition Imbalance → Excitation-Inhibition Imbalance

HCN1-Related Developmental and Epileptic Encephalopathy via Cortical Network Hyperexcitability → Excitation-Inhibition Imbalance

Hemiconvulsion-Hemiplegia-Epilepsy Syndrome via Epileptogenic Reorganization of the Damaged Hemisphere → Seizure Generation and Epileptogenesis , Drug-Resistant Focal Epilepsy from the Affected Hemisphere → Recurrent Unprovoked Seizures

Hemimegalencephaly via Intrinsically Epileptogenic Dysplastic Cortex → Neuronal Hyperexcitability and Hypersynchrony , Drug-Resistant Epilepsy of Infantile Onset → Recurrent Unprovoked Seizures

HNRNPU-Related Developmental and Epileptic Encephalopathy via Impaired Synapse Formation and Circuit Maturation → Ion Channel and Synaptic Dysfunction , Cortical Network Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Recurrent Seizures → Recurrent Unprovoked Seizures

Hyperprolinemia Type 2 via Seizures and Metabolic Encephalopathy → Seizure Generation and Epileptogenesis

Infantile Spasms via Developing brain epileptic network hyperexcitability → Excitation-Inhibition Imbalance

Intellectual Disability Autosomal Dominant 52 via Cortical Excitation-Inhibition Imbalance → Excitation-Inhibition Imbalance , Pyramidal Neuron Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Seizures → Recurrent Unprovoked Seizures

Isolated Sulfite Oxidase Deficiency via Loss of GABAergic Inhibition → Excitation-Inhibition Imbalance

Juvenile Absence Epilepsy via Altered Thalamic Low-Threshold Calcium Bursting → Ion Channel and Synaptic Dysfunction , Aberrant GABAergic Inhibition in the Thalamic Reticular Nucleus → Excitation-Inhibition Imbalance , Hypersynchronous Thalamocortical Oscillation → Neuronal Hyperexcitability and Hypersynchrony , Generalized Spike-Wave Discharges → Seizure Generation and Epileptogenesis , Absence Seizures → Recurrent Unprovoked Seizures

Juvenile Myoclonic Epilepsy via Impaired GABAergic Cortical Inhibition → Ion Channel and Synaptic Dysfunction , Cortical and Thalamocortical Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Myoclonic and Generalized Seizures → Recurrent Unprovoked Seizures

KCNA2-Related Developmental and Epileptic Encephalopathy via Network Excitation-Inhibition Imbalance and Seizures → Neuronal Hyperexcitability and Hypersynchrony

KCNB1-Related Developmental and Epileptic Encephalopathy via KCNB1 Variant and Altered Kv2.1 Channel Function → Ion Channel and Synaptic Dysfunction , Excitation-Inhibition Imbalance , Neuronal Hyperexcitability and Hypersynchrony

KCNQ2 Developmental and Epileptic Encephalopathy via Neuronal M Channel Dysfunction → Ion Channel and Synaptic Dysfunction , Neuronal Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Neonatal-Onset Seizures with Burst-Suppression EEG → Recurrent Unprovoked Seizures

Lennox-Gastaut Syndrome via Cortical Excitation-Inhibition Imbalance → Excitation-Inhibition Imbalance , Multiple Drug-Resistant Seizure Types → Recurrent Unprovoked Seizures

MERRF Syndrome via Cortical Neuronal Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Progressive Myoclonic Epilepsy → Recurrent Unprovoked Seizures

Myoclonic Epilepsy in Infancy via Age-Restricted Generalized Cortical Hyperexcitability of Infancy → Neuronal Hyperexcitability and Hypersynchrony , Brief Generalized Myoclonic Seizures → Recurrent Unprovoked Seizures

NEUROD2-Related Developmental and Epileptic Encephalopathy via Neuronal Hyperactivity → Neuronal Hyperexcitability and Hypersynchrony , Seizures → Recurrent Unprovoked Seizures

PACS2-Related Developmental and Epileptic Encephalopathy via Cortical Network Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Neonatal-Onset Epilepsy with Age-Dependent Improvement → Recurrent Unprovoked Seizures

Paroxysmal Dyskinesia via Presynaptic Release Failure and Neuronal Hyperexcitability → Ion Channel and Synaptic Dysfunction

PCDH19 Clustering Epilepsy via Neuronal Network Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Fever-Sensitive Clustering Seizures → Recurrent Unprovoked Seizures

Photosensitive Epilepsy via Reduced Alpha-Rhythm Network Inhibition → Excitation-Inhibition Imbalance , Visual Cortical Hyperexcitability to Flickering Light and Pattern Stimulation → Neuronal Hyperexcitability and Hypersynchrony

Photosensitive Occipital Lobe Epilepsy via Abnormal Visual Cortical Response to Photic and Pattern Stimulation → Neuronal Hyperexcitability and Hypersynchrony

PNPO Deficiency via Impaired PLP-Dependent GABA Synthesis and Excitation-Inhibition Imbalance → Excitation-Inhibition Imbalance , Neuronal Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , B6-Vitamer-Responsive Neonatal Seizures → Recurrent Unprovoked Seizures

Post-Traumatic Epilepsy via GABAergic Interneuron Loss → Excitation-Inhibition Imbalance , Epileptogenesis During the Latent Period → Seizure Generation and Epileptogenesis , Late Unprovoked Seizures → Recurrent Unprovoked Seizures

Progressive Myoclonic Epilepsy Type 7 via KCNC1 (Kv3.1) Dominant-Negative Loss of Function → Ion Channel and Synaptic Dysfunction , Cortical Excitation-Inhibition Imbalance → Excitation-Inhibition Imbalance , Cortical Reflex Myoclonus and Seizures → Neuronal Hyperexcitability and Hypersynchrony

Progressive Myoclonic Epilepsy Type 8 via Progressive Myoclonus Epilepsy Syndrome → Recurrent Unprovoked Seizures

Pyridoxine-Dependent Epilepsy via Impaired PLP-Dependent GABA Synthesis and Excitation-Inhibition Imbalance → Excitation-Inhibition Imbalance , Neuronal Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Pyridoxine-Responsive Neonatal Seizures → Recurrent Unprovoked Seizures

Rasmussen Encephalitis via Unihemispheric Cortical Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Drug-Resistant Focal Seizures and Epilepsia Partialis Continua → Recurrent Unprovoked Seizures

RHOBTB2-Related Developmental and Epileptic Encephalopathy via Altered Neuronal Excitability → Neuronal Hyperexcitability and Hypersynchrony , Seizures and Developmental Encephalopathy → Recurrent Unprovoked Seizures

Ring Chromosome 20 Syndrome via Frontally Predominant Cortical Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Drug-Resistant Focal Epilepsy → Recurrent Unprovoked Seizures

SCN1B-Related Developmental and Epileptic Encephalopathy via Biallelic SCN1B Loss-of-Function Variant → Ion Channel and Synaptic Dysfunction , Regionally Restricted Network Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Refractory Multifocal and Generalized Seizures → Seizure Generation and Epileptogenesis

SCN2A-Related Developmental and Epileptic Encephalopathy via Increased Nav1.2 Sodium Current (Gain of Function) → Ion Channel and Synaptic Dysfunction , Decreased Nav1.2 Sodium Current (Loss of Function) → Ion Channel and Synaptic Dysfunction , Neuronal Hyperexcitability and Network Dysfunction → Neuronal Hyperexcitability and Hypersynchrony , Seizures and Developmental Encephalopathy → Recurrent Unprovoked Seizures

SCN8A-Related Developmental and Epileptic Encephalopathy via Increased Nav1.6 Sodium Current → Ion Channel and Synaptic Dysfunction , Neuronal Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Seizures and Developmental Encephalopathy → Recurrent Unprovoked Seizures

Self-Limited Epilepsy with Autonomic Seizures via Multifocal Cortical Epileptogenicity with Age-Shifting Foci → Neuronal Hyperexcitability and Hypersynchrony , Focal Autonomic Seizures → Recurrent Unprovoked Seizures

Self-Limited Epilepsy with Centrotemporal Spikes via Age-Dependent Perirolandic Cortical Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Focal Sensorimotor (Rolandic) Seizures → Recurrent Unprovoked Seizures

SETD1B-Related Neurodevelopmental Disorder via Generalized Spike-and-Wave Epileptiform Activity → Neuronal Hyperexcitability and Hypersynchrony

SLC12A5-Related Developmental and Epileptic Encephalopathy via Biallelic SLC12A5 Loss-of-Function Variant → Ion Channel and Synaptic Dysfunction , Failure of Fast Synaptic Inhibition → Excitation-Inhibition Imbalance , Neuronal Hyperexcitability and Hypersynchrony , Migrating Multifocal Seizure Activity → Seizure Generation and Epileptogenesis

SLC13A5 Citrate Transporter Disorder via Neuronal Excitability Dysregulation → Excitation-Inhibition Imbalance

SLC25A12-Related Developmental and Epileptic Encephalopathy via Neuronal Hyperexcitability and Seizure Generation → Neuronal Hyperexcitability and Hypersynchrony , Infantile-Onset Epilepsy → Recurrent Unprovoked Seizures

SLC6A1-Related Neurodevelopmental Disorder via Thalamocortical Excitation-Inhibition Imbalance and Generalized Seizures → Neuronal Hyperexcitability and Hypersynchrony

SNAP25-Related Developmental and Epileptic Encephalopathy via Cortical Excitation-Inhibition Imbalance and Seizures → Neuronal Hyperexcitability and Hypersynchrony

SPTAN1-Related Developmental and Epileptic Encephalopathy via Reduced Inhibitory Innervation → Ion Channel and Synaptic Dysfunction , Cortical Network Disinhibition → Excitation-Inhibition Imbalance , Infantile Spasms with Hypsarrhythmia → Recurrent Unprovoked Seizures

Sturge-Weber Syndrome via Neuronal Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Seizures → Recurrent Unprovoked Seizures

STX1B-Related Epilepsy via Temperature-Sensitive Cortical Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony

STXBP1 Encephalopathy via Cortical Excitation-Inhibition Imbalance and Seizures → Neuronal Hyperexcitability and Hypersynchrony

SYNGAP1-Related Developmental and Epileptic Encephalopathy via Cortical Excitation-Inhibition Imbalance → Excitation-Inhibition Imbalance , Neuronal Network Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Generalized Epilepsy → Recurrent Unprovoked Seizures

SZT2-Related Developmental and Epileptic Encephalopathy via Cortical Network Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony , Drug-Resistant Early-Onset Epilepsy → Recurrent Unprovoked Seizures

UBA5-Related Developmental and Epileptic Encephalopathy via Drug-Resistant Epilepsy → Recurrent Unprovoked Seizures

UNC13A-Related Congenital NDD with Epilepsy via Cortical Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony

UNC13A-Related NDD with Seizures and Movement Disorder via Gain-of-Function Neurotransmission → Ion Channel and Synaptic Dysfunction

Unverricht-Lundborg Disease via Cortical Hyperexcitability → Neuronal Hyperexcitability and Hypersynchrony

WWOX-Related Developmental and Epileptic Encephalopathy via Increased Excitatory Synaptic Drive → Ion Channel and Synaptic Dysfunction , Reduced Inhibitory Synaptic Drive → Ion Channel and Synaptic Dysfunction , Cortical Excitation-Inhibition Imbalance → Excitation-Inhibition Imbalance , Neocortical Network Hypersynchrony → Neuronal Hyperexcitability and Hypersynchrony , Early-Onset Drug-Resistant Seizures → Recurrent Unprovoked Seizures

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Pathograph

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Pathophysiology

Ion Channel and Synaptic Dysfunction

trigger

The conserved initiating lesion is an abnormality of neuronal ion channels or synaptic transmission that alters the intrinsic and synaptic excitability of neurons. This encompasses voltage-gated channel variants, neurotransmitter receptor defects, and synaptic-protein abnormalities across genetic and acquired epilepsies.

Neuron CL:0000540

Regulation of Membrane Potential GO:0042391 ABNORMAL Chemical Synaptic Transmission GO:0007268 ABNORMAL

Used by disorders

Autosomal Dominant Epilepsy with Auditory Features as Disrupted LGI1-ADAM22 Trans-Synaptic Complex

Benign Neonatal Seizures as Kv7.2/Kv7.3 M-Channel Dysfunction

Childhood Absence Epilepsy as Enhanced Thalamic T-type Calcium Current

CYFIP2-Related Developmental and Epileptic Encephalopathy as Disrupted Synaptic and Dendritic Spine Remodeling

Dravet_syndrome as SCN1A Gene Mutation

Early-Infantile Developmental and Epileptic Encephalopathy as Impaired Synaptic Vesicle Release and Inhibitory Circuit Formation

Early-Infantile Developmental and Epileptic Encephalopathy as Increased Persistent Sodium Current

Early-Infantile Developmental and Epileptic Encephalopathy as Reduced Kv7.2/Kv7.3 M-Current

Epilepsy of Infancy with Migrating Focal Seizures as Increased Slack Sodium-Activated Potassium Current

Epilepsy with Generalized Tonic-Clonic Seizures Alone as Polygenic Susceptibility to Generalized Epilepsy

Epilepsy with Myoclonic-Atonic Seizures as Impaired GABA Transporter (GAT-1) Function

Febrile Infection-Related Epilepsy Syndrome as Cytokine-Driven Lowering of Seizure Threshold

FGF12-Related Developmental and Epileptic Encephalopathy as Depolarizing Shift in Nav1.6 Fast Inactivation

GABRB3-Related Developmental and Epileptic Encephalopathy as GABRB3 Variant and Beta-3 Subunit Dysfunction

GABRG2-Related Epilepsy as GABRG2 Variant and Gamma-2 Subunit Dysfunction

GNAO1-Related Developmental and Epileptic Encephalopathy as Impaired Gbg Modulation of Presynaptic Calcium Channels

HNRNPU-Related Developmental and Epileptic Encephalopathy as Impaired Synapse Formation and Circuit Maturation

Juvenile Absence Epilepsy as Altered Thalamic Low-Threshold Calcium Bursting

Juvenile Myoclonic Epilepsy as Impaired GABAergic Cortical Inhibition

KCNB1-Related Developmental and Epileptic Encephalopathy as KCNB1 Variant and Altered Kv2.1 Channel Function

KCNQ2 Developmental and Epileptic Encephalopathy as Neuronal M Channel Dysfunction

Paroxysmal Dyskinesia as Presynaptic Release Failure and Neuronal Hyperexcitability

Progressive Myoclonic Epilepsy Type 7 as KCNC1 (Kv3.1) Dominant-Negative Loss of Function

SCN1B-Related Developmental and Epileptic Encephalopathy as Biallelic SCN1B Loss-of-Function Variant

SCN2A-Related Developmental and Epileptic Encephalopathy as Decreased Nav1.2 Sodium Current (Loss of Function)

SCN2A-Related Developmental and Epileptic Encephalopathy as Increased Nav1.2 Sodium Current (Gain of Function)

SCN8A-Related Developmental and Epileptic Encephalopathy as Increased Nav1.6 Sodium Current

SLC12A5-Related Developmental and Epileptic Encephalopathy as Biallelic SLC12A5 Loss-of-Function Variant

SPTAN1-Related Developmental and Epileptic Encephalopathy as Reduced Inhibitory Innervation

UNC13A-Related NDD with Seizures and Movement Disorder as Gain-of-Function Neurotransmission

WWOX-Related Developmental and Epileptic Encephalopathy as Increased Excitatory Synaptic Drive

WWOX-Related Developmental and Epileptic Encephalopathy as Reduced Inhibitory Synaptic Drive

Downstream

Excitation-Inhibition Imbalance

Excitation-Inhibition Imbalance

amplifier

Channel and synaptic dysfunction shift the balance between excitatory (glutamatergic) and inhibitory (GABAergic) signaling toward net excitation, through increased excitation, decreased inhibition, or both. Loss of GABAergic inhibitory tone is a recurrent contributor across epilepsy syndromes.

GABAergic Neuron CL:0000617

GABA Signaling Pathway GO:0007214 DECREASED

Used by disorders

Alpers-Huttenlocher Syndrome as Selective Interneuron and Pyramidal Neuron Loss in Occipital Cortex

Autosomal Dominant Epilepsy with Auditory Features as Dysregulated AMPA Receptor Clustering and Synaptic Excitability

CDKL5 Deficiency Disorder as Disrupted Cortical Excitation-Inhibition Balance

CHD2-Related Developmental and Epileptic Encephalopathy as Cortical Network Hyperexcitability

Developmental and Epileptic Encephalopathy 89

Dravet_syndrome as Neuronal Hyperexcitability

Early-Infantile Developmental and Epileptic Encephalopathy as Excitation-Inhibition Imbalance in Immature Cortical Networks

Epilepsy as Neuronal Hyperexcitability

Epilepsy with Generalized Tonic-Clonic Seizures Alone as Cortico-Thalamocortical Excitation-Inhibition Imbalance

Febrile Infection-Related Epilepsy Syndrome as Cortical Excitation-Inhibition Imbalance

GABRB3-Related Developmental and Epileptic Encephalopathy as Disrupted Excitation-Inhibition Balance in Developing Networks

GABRG2-Related Epilepsy

Genetic Developmental and Epileptic Encephalopathy as Neuronal Excitation-Inhibition Imbalance

GNAO1-Related Developmental and Epileptic Encephalopathy as Cortical Excitation-Inhibition Imbalance

GRIN1-Related Neurodevelopmental Disorder as Disrupted Excitatory Neurotransmission and E/I Imbalance

GRIN2A-Related Epileptic Encephalopathy and Intellectual Disability as Cortical Excitation-Inhibition Imbalance and Network Hyperexcitability

GRIN2B-Related Developmental and Epileptic Encephalopathy as Cortical Excitation-Inhibition Imbalance

HCN1-Related Developmental and Epileptic Encephalopathy as Cortical Network Hyperexcitability

Infantile Spasms as Developing brain epileptic network hyperexcitability

Intellectual Disability Autosomal Dominant 52 as Cortical Excitation-Inhibition Imbalance

Isolated Sulfite Oxidase Deficiency as Loss of GABAergic Inhibition

Juvenile Absence Epilepsy as Aberrant GABAergic Inhibition in the Thalamic Reticular Nucleus

KCNB1-Related Developmental and Epileptic Encephalopathy

Lennox-Gastaut Syndrome as Cortical Excitation-Inhibition Imbalance

Photosensitive Epilepsy as Reduced Alpha-Rhythm Network Inhibition

PNPO Deficiency as Impaired PLP-Dependent GABA Synthesis and Excitation-Inhibition Imbalance

Post-Traumatic Epilepsy as GABAergic Interneuron Loss

Progressive Myoclonic Epilepsy Type 7 as Cortical Excitation-Inhibition Imbalance

Pyridoxine-Dependent Epilepsy as Impaired PLP-Dependent GABA Synthesis and Excitation-Inhibition Imbalance

SLC12A5-Related Developmental and Epileptic Encephalopathy as Failure of Fast Synaptic Inhibition

SLC13A5 Citrate Transporter Disorder as Neuronal Excitability Dysregulation

SPTAN1-Related Developmental and Epileptic Encephalopathy as Cortical Network Disinhibition

SYNGAP1-Related Developmental and Epileptic Encephalopathy as Cortical Excitation-Inhibition Imbalance

WWOX-Related Developmental and Epileptic Encephalopathy as Cortical Excitation-Inhibition Imbalance

Downstream

Neuronal Hyperexcitability and Hypersynchrony

Neuronal Hyperexcitability and Hypersynchrony

central effector

Net excitatory bias produces a hyperexcitable neuronal state in which populations of neurons fire excessively and synchronously. This hypersynchrony is the central effector that converts altered excitability into paroxysmal network discharges.

neuron CL:0000540

Action Potential GO:0001508 INCREASED

Used by disorders

Autosomal Dominant Epilepsy with Auditory Features as Lateral Temporal Cortical Hyperexcitability

Benign Neonatal Seizures as Neonatal Neuronal Hyperexcitability

CACNA1E-Related Developmental and Epileptic Encephalopathy as Neuronal Hyperexcitability and Excitation-Inhibition Imbalance

CDKL5 Deficiency Disorder as Neuronal Network Hyperexcitability

Childhood Absence Epilepsy as Abnormal Thalamocortical Oscillation and Hypersynchrony

Childhood Occipital Visual Epilepsy as Occipital Interictal and Ictal Paroxysmal Discharges

CPLX1-Related Developmental and Epileptic Encephalopathy as Cortical Hyperexcitability and Seizures

CYFIP2-Related Developmental and Epileptic Encephalopathy as Neuronal Network Hyperexcitability

DEPDC5-Related Epilepsy as Focal Cortical Hyperexcitability and Focal-Onset Seizures

Developmental and Epileptic Encephalopathy 89

Developmental and Epileptic Encephalopathy with Spike-Wave Activation in Sleep as Abnormal Frequency-Dependent Cortical Excitability

DNM1 Encephalopathy as Reduced Neurotransmission and Cortical Hyperexcitability

Early-Infantile Developmental and Epileptic Encephalopathy as Burst-Suppression and Hypersynchronous Cortical Discharge

Epilepsy of Infancy with Migrating Focal Seizures as Multifocal Cortical Hyperexcitability

Epilepsy with Generalized Tonic-Clonic Seizures Alone as Generalized Hypersynchronous Discharge

Epilepsy with Myoclonic Absences as Hypersynchronous Three-Hertz Thalamocortical Spike-Wave Oscillation

Epilepsy with Myoclonic-Atonic Seizures as Thalamocortical Network Hyperexcitability

FGF12-Related Developmental and Epileptic Encephalopathy as Increased Intrinsic Neuronal Excitability

GABRB3-Related Developmental and Epileptic Encephalopathy as Neuronal Hyperexcitability and Thalamocortical Hypersynchrony

GABRG2-Related Epilepsy

Genetic Developmental and Epileptic Encephalopathy as Hypersynchronous Network Activity and Seizures

GLUT1 Deficiency Syndrome

Hemimegalencephaly as Intrinsically Epileptogenic Dysplastic Cortex

HNRNPU-Related Developmental and Epileptic Encephalopathy as Cortical Network Hyperexcitability

Intellectual Disability Autosomal Dominant 52 as Pyramidal Neuron Hyperexcitability

Juvenile Absence Epilepsy as Hypersynchronous Thalamocortical Oscillation

Juvenile Myoclonic Epilepsy as Cortical and Thalamocortical Hyperexcitability

KCNA2-Related Developmental and Epileptic Encephalopathy as Network Excitation-Inhibition Imbalance and Seizures

KCNB1-Related Developmental and Epileptic Encephalopathy

KCNQ2 Developmental and Epileptic Encephalopathy as Neuronal Hyperexcitability

MERRF Syndrome as Cortical Neuronal Hyperexcitability

Myoclonic Epilepsy in Infancy as Age-Restricted Generalized Cortical Hyperexcitability of Infancy

NEUROD2-Related Developmental and Epileptic Encephalopathy as Neuronal Hyperactivity

PACS2-Related Developmental and Epileptic Encephalopathy as Cortical Network Hyperexcitability

PCDH19 Clustering Epilepsy as Neuronal Network Hyperexcitability

Photosensitive Epilepsy as Visual Cortical Hyperexcitability to Flickering Light and Pattern Stimulation

Photosensitive Occipital Lobe Epilepsy as Abnormal Visual Cortical Response to Photic and Pattern Stimulation

PNPO Deficiency as Neuronal Hyperexcitability

Progressive Myoclonic Epilepsy Type 7 as Cortical Reflex Myoclonus and Seizures

Pyridoxine-Dependent Epilepsy as Neuronal Hyperexcitability

Rasmussen Encephalitis as Unihemispheric Cortical Hyperexcitability

RHOBTB2-Related Developmental and Epileptic Encephalopathy as Altered Neuronal Excitability

Ring Chromosome 20 Syndrome as Frontally Predominant Cortical Hyperexcitability

SCN1B-Related Developmental and Epileptic Encephalopathy as Regionally Restricted Network Hyperexcitability

SCN2A-Related Developmental and Epileptic Encephalopathy as Neuronal Hyperexcitability and Network Dysfunction

SCN8A-Related Developmental and Epileptic Encephalopathy as Neuronal Hyperexcitability

Self-Limited Epilepsy with Autonomic Seizures as Multifocal Cortical Epileptogenicity with Age-Shifting Foci

Self-Limited Epilepsy with Centrotemporal Spikes as Age-Dependent Perirolandic Cortical Hyperexcitability

SETD1B-Related Neurodevelopmental Disorder as Generalized Spike-and-Wave Epileptiform Activity

SLC12A5-Related Developmental and Epileptic Encephalopathy

SLC25A12-Related Developmental and Epileptic Encephalopathy as Neuronal Hyperexcitability and Seizure Generation

SLC6A1-Related Neurodevelopmental Disorder as Thalamocortical Excitation-Inhibition Imbalance and Generalized Seizures

SNAP25-Related Developmental and Epileptic Encephalopathy as Cortical Excitation-Inhibition Imbalance and Seizures

Sturge-Weber Syndrome as Neuronal Hyperexcitability

STX1B-Related Epilepsy as Temperature-Sensitive Cortical Hyperexcitability

STXBP1 Encephalopathy as Cortical Excitation-Inhibition Imbalance and Seizures

SYNGAP1-Related Developmental and Epileptic Encephalopathy as Neuronal Network Hyperexcitability

SZT2-Related Developmental and Epileptic Encephalopathy as Cortical Network Hyperexcitability

UNC13A-Related Congenital NDD with Epilepsy as Cortical Hyperexcitability

Unverricht-Lundborg Disease as Cortical Hyperexcitability

WWOX-Related Developmental and Epileptic Encephalopathy as Neocortical Network Hypersynchrony

Downstream

Seizure Generation and Epileptogenesis

Seizure Generation and Epileptogenesis

effector

Hypersynchronous discharges manifest as seizures. Over time, seizure-related and lesion-related processes drive epileptogenesis — network reorganization that lowers seizure threshold and renders the brain chronically prone to spontaneous seizures.

neuron CL:0000540

Used by disorders

Benign Neonatal Seizures as Neonatal Focal Seizure Generation

Epilepsy with Generalized Tonic-Clonic Seizures Alone as Recruitment of Motor Systems into Tonic-Clonic Output

Febrile Infection-Related Epilepsy Syndrome as Super-Refractory Status Epilepticus

FGF12-Related Developmental and Epileptic Encephalopathy as Epileptiform Network Activity

GABRB3-Related Developmental and Epileptic Encephalopathy as Seizure Generation and Developmental Encephalopathy

Hemiconvulsion-Hemiplegia-Epilepsy Syndrome as Epileptogenic Reorganization of the Damaged Hemisphere

Hyperprolinemia Type 2 as Seizures and Metabolic Encephalopathy

Juvenile Absence Epilepsy as Generalized Spike-Wave Discharges

Post-Traumatic Epilepsy as Epileptogenesis During the Latent Period

SCN1B-Related Developmental and Epileptic Encephalopathy as Refractory Multifocal and Generalized Seizures

SLC12A5-Related Developmental and Epileptic Encephalopathy as Migrating Multifocal Seizure Activity

Downstream

Recurrent Unprovoked Seizures

Recurrent Unprovoked Seizures

consequence

The clinical endpoint is the state of recurrent, unprovoked seizures that defines epilepsy. Seizures may continue to evolve over the lifespan as the underlying network continues to reorganize.

neuron CL:0000540

Used by disorders

Alpers-Huttenlocher Syndrome as Intractable Focal Epilepsy and Epilepsia Partialis Continua

Autosomal Dominant Epilepsy with Auditory Features as Focal Seizures with Auditory Features

CDKL5 Deficiency Disorder as Early-Onset Intractable Epilepsy

Childhood Absence Epilepsy as Absence Seizures

Childhood Occipital Visual Epilepsy as Recurrent Brief Diurnal Visual Seizures

CYFIP2-Related Developmental and Epileptic Encephalopathy as Drug-Resistant Epilepsy

DENND5A-Related Developmental and Epileptic Encephalopathy as Seizure Generation and Developmental and Epileptic Encephalopathy

Developmental and Epileptic Encephalopathy 89 as Early-Onset Epileptic Seizures

Developmental and Epileptic Encephalopathy with Spike-Wave Activation in Sleep as Focal and Atypical Absence Seizures

Early-Infantile Developmental and Epileptic Encephalopathy as Recurrent Drug-Resistant Seizures

Epilepsy of Infancy with Migrating Focal Seizures as Migrating Focal Seizure Generation

Epilepsy with Generalized Tonic-Clonic Seizures Alone as Recurrent Unprovoked Generalized Tonic-Clonic Seizures

Epilepsy with Myoclonic Absences as Rhythmic Myoclonus with Progressive Tonic Contraction

Epilepsy with Myoclonic-Atonic Seizures as Myoclonic-Atonic and Generalized Seizures

Febrile Infection-Related Epilepsy Syndrome as Chronic Drug-Resistant Epilepsy and Neurocognitive Sequelae

FGF12-Related Developmental and Epileptic Encephalopathy as Early-Onset Refractory Seizures

Focal Cortical Dysplasia Type II as Drug-Resistant Focal Epilepsy

GABRB3-Related Developmental and Epileptic Encephalopathy as Drug-Resistant Epilepsy with Developmental Impairment

GLUT1 Deficiency Syndrome as Recurrent Pharmacoresistant Seizures

GNAO1-Related Developmental and Epileptic Encephalopathy as Developmental and Epileptic Encephalopathy

Hemiconvulsion-Hemiplegia-Epilepsy Syndrome as Drug-Resistant Focal Epilepsy from the Affected Hemisphere

Hemimegalencephaly as Drug-Resistant Epilepsy of Infantile Onset

HNRNPU-Related Developmental and Epileptic Encephalopathy as Recurrent Seizures

Intellectual Disability Autosomal Dominant 52 as Seizures

Juvenile Absence Epilepsy as Absence Seizures

Juvenile Myoclonic Epilepsy as Myoclonic and Generalized Seizures

KCNQ2 Developmental and Epileptic Encephalopathy as Neonatal-Onset Seizures with Burst-Suppression EEG

Lennox-Gastaut Syndrome as Multiple Drug-Resistant Seizure Types

MERRF Syndrome as Progressive Myoclonic Epilepsy

Myoclonic Epilepsy in Infancy as Brief Generalized Myoclonic Seizures

NEUROD2-Related Developmental and Epileptic Encephalopathy as Seizures

PACS2-Related Developmental and Epileptic Encephalopathy as Neonatal-Onset Epilepsy with Age-Dependent Improvement

PCDH19 Clustering Epilepsy as Fever-Sensitive Clustering Seizures

PNPO Deficiency as B6-Vitamer-Responsive Neonatal Seizures

Post-Traumatic Epilepsy as Late Unprovoked Seizures

Progressive Myoclonic Epilepsy Type 8 as Progressive Myoclonus Epilepsy Syndrome

Pyridoxine-Dependent Epilepsy as Pyridoxine-Responsive Neonatal Seizures

Rasmussen Encephalitis as Drug-Resistant Focal Seizures and Epilepsia Partialis Continua

RHOBTB2-Related Developmental and Epileptic Encephalopathy as Seizures and Developmental Encephalopathy

Ring Chromosome 20 Syndrome as Drug-Resistant Focal Epilepsy

SCN2A-Related Developmental and Epileptic Encephalopathy as Seizures and Developmental Encephalopathy

SCN8A-Related Developmental and Epileptic Encephalopathy as Seizures and Developmental Encephalopathy

Self-Limited Epilepsy with Autonomic Seizures as Focal Autonomic Seizures

Self-Limited Epilepsy with Centrotemporal Spikes as Focal Sensorimotor (Rolandic) Seizures

SLC25A12-Related Developmental and Epileptic Encephalopathy as Infantile-Onset Epilepsy

SPTAN1-Related Developmental and Epileptic Encephalopathy as Infantile Spasms with Hypsarrhythmia

Sturge-Weber Syndrome as Seizures

SYNGAP1-Related Developmental and Epileptic Encephalopathy as Generalized Epilepsy

SZT2-Related Developmental and Epileptic Encephalopathy as Drug-Resistant Early-Onset Epilepsy

UBA5-Related Developmental and Epileptic Encephalopathy as Drug-Resistant Epilepsy

WWOX-Related Developmental and Epileptic Encephalopathy as Early-Onset Drug-Resistant Seizures