Modulation of epileptiform EEG discharges in juvenile myoclonic epilepsy: An investigation of reflex epileptic traits (original) (raw)

Provocative and inhibitory effects of a video-EEG neuropsychologic protocol in juvenile myoclonic epilepsy

Epilepsia, 2009

Purpose: Studies suggest that higher cognitive functions could precipitate seizures in juvenile myoclonic epilepsy (JME). The present study aimed to analyze the effects of higher mental activity on epileptiform discharges and seizures in patients with JME and compare them to those of habitual methods of activation. Methods: Seventy-six patients with JME (41 female) underwent a video-EEG (electroencephalography) neuropsychologic protocol (VNPP) and habitual methods of activation for 4-6 h. Results: Twenty-nine of the 76 (38.2%) presented provocative effect, and inhibition was seen in 28 of 31 (90.3%). A mixed effect was observed in 11 (35.5%), and 30 patients (39.5%) suffered no effect of VNPP. Action-programming tasks were more effective than thinking in provoking epileptiform discharges (23.7% and 11.0% of patients, respectively, p = 0.03). Inhibitory effect was observed

The Effect of Cognitive Functions on EEG in Patients with Juvenile Myoclonic Epilepsy

Journal of the Turkish Epilepsi Society, 2013

Objectives: In this study, we aimed to show any effect of different types of cognitive activities on the electroencephalography (EEG) of patients with juvenile myoclonic epilepsy (JME). Methods: 30 patients with JME who stated that their seizures are not effected by any mental activity were submitted to a 30-minute standard awake video EEG. A neuropsychological activation battery (NPA) was performed during the ongoing video EEG. Results: The provocative effect of at least one test of NPA was observed in seven of 30 patients (23.3%) and the inhibitory effect of NPA was observed in nine of 30 patients (30.0%). Conclusion: We demonstrated that increased attention, concentration, and the tests associated generally with the frontal lobe functions were crucial for provocating the EEG discharges. This may support the studies with neuropsychological tests and structural neuroimaging techniques showing focal cortical abnormalities mainly associated with frontal lobe in JME.

The long-term course of seizure susceptibility in two patients with juvenile myoclonic epilepsy

Seizure, 2002

We have observed epileptic seizures of juvenile myoclonic epilepsy (JME) to be surprisingly sensitive to higher mental activity. The purpose of the present study was to examine changes over time in seizure susceptibility in two patients with JME who we followed-up for over 20 years. During the period, they were repeatedly subjected to provocative cognitive tasking, that is, to 'neuropsychological EEG activation'. Tasks included reading, speaking, writing, written arithmetic, mental calculation, and spatial construction. During the first 15 years after the onset of symptoms, higher mental activities, mainly associated with use of the hands, i.e. writing, written calculation, and spatial construction, as well as physiological factors, such as sleep deprivation, awakening, and fatigue, precipitated the seizures. Generalized tonic-clonic and absence seizures but not myoclonic seizures disappeared almost completely after antiepileptic treatment. After age 30, the provocative effe...

Neurophysiology of juvenile myoclonic epilepsy

Epilepsy & Behavior, 2013

Juvenile myclonic epilepsy (JME) can be firmly diagnosed by a careful interview of the patient focusing on the seizures and by the EEG with the help, if necessary, of long-term video-EEG monitoring using sleep and/or sleep deprivation. Background activity is normal. The interictal EEG shows diffuse or generalized spike-wave (SW) and polyspike-wave (PSW) discharges. In some patients, non-specific changes or misleading features such as focal changes are found. Changes are mostly seen at sleep onset and at awakening. Provoked awakenings are more likely to activate interictal paroxysmal abnormalities than spontaneous awakenings. The presence of a photoparoxysmal response with or without myoclonic jerks (MJ) is common (30% of the cases). Myoclonic jerks are associated with a discharge of fast, irregular, generalized PSWs that predominate anteriorly. Myoclonic jerks appear to be associated with rhythmic EEG (spike) potentials at around 20 Hz. These frequencies are in the range of movement-related fast sensorimotor cortex physiological rhythms. The application of jerk-locked averaging technique has provided findings consistent with a cortical origin of MJ. Paired TMS (transcranial magnetic stimulation) studies showed a defective intracortical inhibition, due to impaired GABA-A mediated mechanisms. In this review, we present the EEG characteristics of JME with particular emphasis on the pathophysiology of MJ and on the role of sleep deprivation on interictal and ictal changes.

Clinical and EEG characteristics of Juvenile Myoclonic Epilepsy

Pakistan Journal of Medical Sciences, 1969

Objective: To determine the clinical and electroencephalographic characteristics of patients with Juvenile Myoclonic Epilepsy (JME). Methods: In this descriptive case series study, 60 patients of Juvenile myoclonic epilepsy (JME) were included. After detailed history clinical examination, Electroencephalography (EEG) with standard protocol was performed in all patients and was analyzed by a neurologist. Results: Out of 60 patients, 26 (43.3%) were males and 34 (56.6%) were females. Mean age at the onset of myoclonic jerks (MJ) and generalized tonic clonic seizures (GTCS) was 13.7 ± 2.12 years and 14.15 ± 1.79 years respectively. Average delay in the diagnosis was 5.2 years. Myoclonic jerks (MJ) were present in all patients, GTCS in 52 (86.6%), and absence seizures in 8 (13.33%) patients. 6 (10%) had only Myoclonic Jerks. First seizure type was MJ in 52 (86.6%) and absence in 8 (13.3%). Most common precipitating factors were sleep deprivation in 80% and fatigue in 66.6%. Family history for epilepsy was positive in 20%. Diagnosis by referring physicians was JME in only 6 (10%) patients. EEG was abnormal in 42 patients (70%) showing generalized , 4-to 6-Hz polyspike and wave in 27 (45%), generalized single spike/ sharp waves in 7 patients (11.6%), 8 (13.3%) patients had 3-Hz spike-and-wave (SW) activity in addition to the polyspike-and-wave (PSW) pattern. Independent focal EEG abnormalities were noted in 12 patients (20%). Conclusion: Many of our patients were misdiagnosed by the referring physicians and were prescribed inappropriate antiepileptic drugs. Factors causing misdiagnosis were failure to elicit history of myoclonic jerks, misinterpreting myoclonic jerks as partial seizures and misinterpretation of EEG abnormalities.

Abnormal response to photic stimulation in Juvenile Myoclonic Epilepsy: An EEG-fMRI study

Epilepsia, 2014

Objective: Juvenile myoclonic epilepsy (JME) is a young-onset electroclinical syndrome, characterized by myoclonic, generalized tonic-clonic, and possibly typical absence seizures. Interictal electroencephalography (EEG) displays 3-6 Hz spike/ polyspike and wave pattern. Photosensitivity is common. Our aim was to explore the blood oxygen level-dependent (BOLD) response evoked by a highly provocative photic stimulus in a cohort of people with JME compared to a group of nonphotosensitive healthy controls, and to investigate the hemodynamic phenomena seen in patients with photosensitive JME. Methods: We studied 13 JME patients and 18 healthy controls using EEG-functional magnetic resonance imaging (fMRI) performed during low luminance intermittent photic stimulation (IPS). The BOLD response to IPS was investigated both in JME and control groups. In photosensitive JME subjects, we also performed a dynamic evaluation of BOLD signal changes evoked by the photoparoxysmal response (PPR) in a time frame ranging from 10 s before the onset of the EEG paroxysm up until 10 s afterward. Results: The IPS evoked a positive BOLD response in striate and extrastriate visual areas, which was less in JME patients than in controls. Moreover, people with JME had a reduced positive BOLD response in the frontoparietal areas and putamen but a stronger negative BOLD response in the primary sensorimotor cortex (SM1) and in cortical regions belonging to the default mode network (DMN). In JME, the dynamic evaluation of BOLD signal changes related to PPR revealed an early positive response in the putamen and SM1, followed by BOLD signal decrements in the putamen, caudate nuclei, thalami, and SM1. Significance: Our results confirm the hypothesis that people with JME might have an altered interaction between the motor circuit and other neuronal networks, with prominent involvement of basal ganglia circuitry. The PPR could be a final expression of pathogenic phenomena occurring in the striato-thalamocortical system, possibly a core feature of system epilepsy JME.

The cognitive effects of interictal epileptiform EEG discharges and short nonconvulsive epileptic seizures

Epilepsia, 2012

Purpose: Educational difficulties or even severe cognitive deterioration is seen in many childhood epilepsy syndromes. Many of those cognitive deficits are related directly to the brain disorder underlying the epilepsy syndrome. However, in other types of epilepsy, the epileptic seizures and/or epileptiform activity can be the dominant factor. This is especially unknown for the more ''subtle'' short nonconvulsive seizure types. For this reason, we analyzed a new cohort of children. Methods: A cross-sectional study of 188 children with epilepsy. Electroencephalography (EEG)-video recordings and cognitive testing were performed simultaneously. The results of children with short nonconvulsive seizures during a 2-h testing session were compared with all children with epilepsy without seizures during the 2-h cognitive testing session and with controls without epilepsy. In a second analysis the cognitive effects of frequency of epileptiform EEG discharges were analyzed. Key Findings: The cognitive effects of short nonconvulsive seizures were large, ranging from 0.5 to 1 standard deviation and concerned global cognitive function, speed of central information processing, and memory function. In children without seizures during cognitive testing, the occurrence of frequent epileptiform discharges showed more subtle effects. These effects were independent from the occurrence of short nonconvulsive seizures. Significance: We concluded that although the effect is less pronounced in number of areas involved and magnitude, the type of association between frequent epileptiform activity (>1% of the time) and cognitive function in children with epilepsy is comparable to the association between short nonconvulsive seizures and cognitive function.

Phenotyping juvenile myoclonic epilepsy. Praxis induction as a biomarker of unfavorable prognosis

Seizure, 2015

Juvenile myoclonic epilepsy (JME) is the most common type of idiopathic generalized epilepsy (IGE); comprising 5-10% of all epilepsies [1]. The cardinal symptoms are myoclonic jerks of upper extremities; often precipitated by sleep deprivation [2,3]. Chronosensitivity is necessary for diagnosis. Occurrence of myoclonia exclusively on or after awakening and age of onset between 10 and 25 years are considered Class I diagnostic criteria while Class II comprises myoclonia occurring predominantly on or after awakening; sensitivity to visual stimuli; praxis induction (PI) and a wider 6-25 years range for onset of epilepsy [4]. Generalized tonic-clonic seizures (GTCS) are present in approximately 80-95% of patients and one third has absences [2]. Recently; data regarding long term prognosis of JME have been published [5-10]. Despite the recognition of some prognostic predictors such as presence of all three types of seizures; psychiatric comorbidity and drug resistance [10-13]; clinical diversity of JME is remarkable and the severity of the disorder itself has only rarely been analyzed [14-16]. PI, one of the four reflex epileptic traits that occur in JME, is defined as precipitation of seizures or epileptiform discharges (ED)

Neuropsychology of Epilepsy

Epilepsia, 2008

The neuropsychological approach to epilepsy is indispensable for assessment of cognitive function in an interictal period including pre-and postsurgical evaluation, and for disclosing the semiology of nonconvulsive status epilepticus. Another use of the neuropsychological approach is to identify a seizure-precipitating factor by loading systematic cognitive tasking, termed "neuropsychological EEG activation" (NPA), during standard EEG recordings. Methods: In this study, NPA tasks consisted of reading, speaking, writing, written arithmetic calculation, mental arithmetic calculation, and spatial construction. Results: The NPA tasks provoked epileptic discharges in 7.9% of the 480 epileptic patients and were often accompanied by myoclonic seizures. Among the cognitive tasks, mental activities mainly associated with use of the hands [i.e., writing (68.4%), written calculation (55.3%), and spatial construction (63.2%)] provoked the most discharges. Seizure-precipitating mental activities were found to be almost exclusively related to idiopathic generalized epilepsies (IGEs). Conclusions: These results suggest that NPA is a useful tool for examining the relationship between cognitive function and epileptic seizures, and that the IGE patients with myoclonic seizures are vulnerable to higher mental activity.