Track topics on Twitter Track topics that are important to you
It has been proposed that the underlying epileptic process is mediated by changes in both excitatory and inhibitory circuits leading to the formation of hyper-excitable seizure networks. In this review we aim to shed light on the many physiological factors that modulate excitability within these networks. These factors have been discussed extensively in many reviews each as a separate entity and cannot be extensively covered in a single manuscript. Thus for the purpose of this work in which we aim to bring those factors together to explain how they interact with epilepsy, we only provide brief descriptions. We present reported evidence supporting the existence of the epileptic brain in several states; interictal, peri-ictal and ictal, each with distinct excitability features. We then provide an overview of how many physiological factors influence the excitatory/inhibitory balance within the interictal state, where the networks are presumed to be functioning normally. We conclude that these changes result in constantly changing states of cortical excitability in patients with epilepsy.
Department of Clinical Neurosciences, St Vincent's Hospital, Fitzroy, Australia; Department of Medicine, The University of Melbourne, Parkville, Australia; Department of Electrical and Electronic Engineering, The University of Melbourne, Parkville, Austra
This article was published in the following journal.
Transcranial magnetic stimulation (TMS) has been used to elucidate the altered balance between excitatory and inhibitory circuits in the motor cortex in epilepsy; however, TMS could not well assess ex...
Chronic pain and epilepsy together affect hundreds of millions of people worldwide. While traditional pharmacotherapy provides essential relief to the majority of patients, a large proportion remains ...
Over the past decade enhanced activation of the mammalian target of rapamycin (mTOR)-signaling cascade has been identified in focal malformations of cortical development (MCD) subtypes, which have bee...
The amplitudes of mu and beta (7-26 Hz) oscillations measured by electroencephalography over the sensorimotor areas are suppressed during motor imagery as well as during voluntary movements. This phen...
Unverricht-Lundborg disease (EPM1) is characterized by stimulus-sensitive and action-activated myoclonus, tonic-clonic seizures and ataxia. Several disease-related alterations in cortical structure an...
The identification of the epileptogenic zone (EZ) during pharmacoresistant focal epilepsy presurgical assessment frequently requires intracranial recordings like stereo-electroencephalogra...
Epileptic disease is characterised by enhanced brain excitability. Low frequency repetitive transcranial magnetic stimulation (rTMS) can be an effective treatment for refractory frontal ep...
The aim of the study is to evaluate the cortical excitability in the severe brain injured patients. We hypothesize that: 1. There is a continuous decrease in intracortical inhibition fr...
Focal cortical dysplasia (FCD) is a common finding in epilepsy surgery in pediatric patients. Children with intractable epilepsy would have extensive tests to identify the cause of epilep...
The purpose of this research is to determine whether athletes with concussion have changes in cortical excitability. Single and paired transcranial magnetic stimulation (TMS) can be used ...
A neurosurgical procedure that removes or disconnects the epileptogenic CEREBRAL CORTEX of a hemisphere. Hemispherectomy is usually performed for patients with intractable unilateral EPILEPSY due to malformations of cortical development or brain lesions. Depending on the epileptogenic area in the hemisphere, cortical removal can be total or partial.
A disorder characterized by recurrent partial seizures marked by impairment of cognition. During the seizure the individual may experience a wide variety of psychic phenomenon including formed hallucinations, illusions, deja vu, intense emotional feelings, confusion, and spatial disorientation. Focal motor activity, sensory alterations and AUTOMATISM may also occur. Complex partial seizures often originate from foci in one or both temporal lobes. The etiology may be idiopathic (cryptogenic partial complex epilepsy) or occur as a secondary manifestation of a focal cortical lesion (symptomatic partial complex epilepsy). (From Adams et al., Principles of Neurology, 6th ed, pp317-8)
A localization-related (focal) form of epilepsy characterized by recurrent seizures that arise from foci within the temporal lobe, most commonly from its mesial aspect. A wide variety of psychic phenomena may be associated, including illusions, hallucinations, dyscognitive states, and affective experiences. The majority of complex partial seizures (see EPILEPSY, COMPLEX PARTIAL) originate from the temporal lobes. Temporal lobe seizures may be classified by etiology as cryptogenic, familial, or symptomatic (i.e., related to an identified disease process or lesion). (From Adams et al., Principles of Neurology, 6th ed, p321)
Abnormalities in the development of the CEREBRAL CORTEX. These include malformations arising from abnormal neuronal CELL PROLIFERATION or APOPTOSIS; abnormal neuronal migration; and abnormal establishment of cortical organization via neurite extension, synaptogenesis, or neuronal maturation. As well as mutations effecting these developmental processes directly, there are a variety of inborn metabolic errors, such as PEROXISOMAL DISORDERS and mitochondrial and pyruvate metabolic disorders which effect them secondarily and also exhibit these malformations. They are common causes of EPILEPSY and developmental delay and are often a component of multiple congenital anomalies.
A technique that involves the use of electrical coils on the head to generate a brief magnetic field which reaches the CEREBRAL CORTEX. It is coupled with ELECTROMYOGRAPHY response detection to assess cortical excitability by the threshold required to induce MOTOR EVOKED POTENTIALS. This method is also used for BRAIN MAPPING, to study NEUROPHYSIOLOGY, and as a substitute for ELECTROCONVULSIVE THERAPY for treating DEPRESSION. Induction of SEIZURES limits its clinical usage.
Latest News Clinical Trials Research Drugs Reports Corporate
Epilepsy is defined as a disorder of brain function characterized by recurrent seizures that have a sudden onset. (Oxford Medical Dictionary). A seizure is caused by a sudden burst of excess electrical activity in the brain, causing a tempora...
Latest News Clinical Trials Research Drugs Reports Corporate
Of all the types of Dementia, Alzheimer's disease is the most common, affecting around 465,000 people in the UK. Neurons in the brain die, becuase 'plaques' and 'tangles' (mis-folded proteins) form in the brain. People with Al...