First seizures associated with playing electronic screen games: a community-based study in Great Britain

Video game exposure in children with epilepsy: EEG and clinical findings

OBJECTIVE

To investigate the effects of video game exposure on pediatric epilepsy patients, focusing on electroencephalography (EEG) and clinical outcomes.

METHODS

A total of 94 pediatric epilepsy patients aged 6-18 years (juvenile idiopathic generalized epilepsy, childhood absence epilepsy, self-limited idiopathic focal epilepsy [SeLEAS and SeLECTS]) and 57 non-epileptic controls were enrolled. EEG recordings were obtained while patients were awake, asleep, and during video game play. The impact of video games was analyzed across different epilepsy subgroups and according to epilepsy control status.

RESULTS

Twenty-five patients with EEG deterioration in the entire group, three of whom were from the control group (p = 0.032). Among juvenile idiopathic generalized epilepsy patients, 2 of 21 controlled and 6 of 11 uncontrolled patients were adversely affected by video games (p = 0.01). In the SeLECTS group, none of the controlled patients and 3 of 11 uncontrolled patients showed adverse effects (p = 0.063). In the absence epilepsy and SeLEAS groups, epilepsy status did not significantly affect video game response (p = 0.250, p = 0.603). Patients with pattern sensitivity and photosensitivity had a higher risk of EEG deterioration during video game play than those without these sensitivities.

CONCLUSIONS

Playing selected video games is safer for patients with juvenile idiopathic generalized epilepsies and the SeLECTS group when precautions are taken, and both EEG and clinical conditions are under control. However, video games pose a risk for patients with absence epilepsy and SeLEAS, regardless of epilepsy control status. These findings underscore the need for individualized assessments and tailored recommendations for video game exposure in pediatric epilepsy patients.

Bromodomain-containing protein 2 gene polymorphism among patients with photosensitive epilepsy in Indonesia

OBJECTIVES

Genetic-associated epilepsy in the Indonesian population is rarely discussed, and no study was specifically studied about photosensitive epilepsy. The fundamental goal of this research endeavor was to evaluate whether the single nucleotide polymorphism (SNP) of the Bromodomain-Containing Protein 2 (BRD2) gene gives vulnerability to photosensitive epilepsy among Indonesian descent.

METHODS

This observational case-control study includes patients of Indonesian descent with Javanese ancestry. Clinical and neurophysiological data, along with electroencephalographic (EEG) recordings, were used to diagnose epilepsy and photosensitive epilepsy. Blood samples were collected and analyzed for BRD2 gene SNPs (rs206781, rs188245, and rs15912) using polymerase chain reaction (PCR), electrophoresis, and the Sanger sequencing method.

RESULTS

This study included 27 participants, consisting of 17 patients in the epilepsy group (nine patients with photosensitive epilepsy and eight patients without photosensitive epilepsy) and 10 patients in the non-epilepsy group. Significant statistical differences were found in genotype (rs206781, p = 0.008 and rs188245, p = 0.004) and allele frequencies (rs206781, p < 0.001 and rs188245, p < 0.001) of the BRD2 gene in Indonesian descent with Javanese race patients diagnosed with photosensitive epilepsy and in those without this condition.

SIGNIFICANCE

Our study corroborates the observation that genetic diversity within the BRD2 locus (rs206781 and rs188245) is associated with PE in Indonesian descendants of the Javanese race. To acquire a complete knowledge of the development of photosensitive epilepsy, further polymorphism studies at other SNP locations or genes are necessary.

PLAIN LANGUAGE SUMMARY

This study investigated whether genetic differences in the BRD2 gene were linked to photosensitive epilepsy (a type of epilepsy triggered by visual stimuli like flashing lights) in individuals of Indonesian Javanese descent. We analyzed deoxyribonucleic acid (DNA) samples from patients with epilepsy, including those with photosensitive epilepsy, and found that certain variations in the BRD2 gene were significantly more common in people with photosensitive epilepsy. These findings imply that genetic factors, specifically variations in the BRD2 gene, could elevate the risk of individuals in this population experiencing photosensitive epilepsy.

Clinical profiles and prognostic factors in reflex epilepsy: Insights from a Taiwanese cohort

PURPOSE

To investigate the clinical characteristics, treatment, and prognosis of patients with reflex epilepsies in Taiwan.

METHODS

Patients with reflex epilepsies (RE) induced by specific trigger factors from July 2000 to May 2024, were recruited at Chang Gung Memorial Hospital, Linkou, Taiwan. All patients had at least 12 months of follow-up. Demographic data, antiseizure medication (ASM) treatment, stimulus avoidance, and seizure outcome were analyzed. We further divided the patients into extrinsic and intrinsic RE groups based on the nature of stimuli. We also categorized them into ongoing seizure and seizure-free groups based on their seizure control. Fisher's exact test and Independent-Samples Mann-Whitney U Test were used to evaluate associations between clinical factors and prognosis. Multivariate logistic regression analysis was further carried out to determine the predictors of seizure outcomes.

RESULTS

In this study, 81 patients with reflex epilepsies (RE) were analyzed, focusing on those with extrinsic (photosensitive) and intrinsic (Mah-Jong-related) seizure triggers. Patients with extrinsic RE were significantly younger (mean age 40.4 years) than those with intrinsic RE (mean age 64.4 years, p < 0.001) and had a notably earlier onset of reflex seizures (21.9 years vs. 49.7 years, p < 0.001). A higher proportion of extrinsic RE patients experienced spontaneous seizures (98 %) compared to intrinsic RE (40 %). Abnormal EEG findings were more prevalent in the extrinsic group (94.1 %) than in the intrinsic group (66.7 %). Ninety-eight percent of patients with extrinsic RE were treated with antiseizure medications (ASMs), with an average of 2.2 ASMs per patient, compared to 73.3 % and 1.2 ASMs in patients with intrinsic RE. Furthermore, the rate of stimulus avoidance was significantly higher among those with intrinsic RE, at 43.3 % compared to 3.9 % in the extrinsic group (p < 0.001). Both groups achieved similar seizure-free outcomes (68.6 % in extrinsic vs. 63.3 % in intrinsic RE), but stimulus avoidance is independently associated with a reduced likelihood of ongoing seizures (p = 0.038), with an odds ratio (OR) of 0.110.

CONCLUSION

Intrinsic RE exhibited a later onset of spontaneous and reflex seizures than extrinsic RE. Avoidance of seizure triggers was more frequent in intrinsic RE and among seizure-free patients, suggesting that stimulus avoidance is crucial for better seizure control and prognosis. On the other hand, patients with extrinsic RE had a lower rate of trigger avoidance but were more likely to receive ASM treatment, suggesting ASM is crucial for managing seizures due to challenges in avoiding environmental triggers. Despite these differences, both groups achieved similar seizure-free outcomes, underscoring the necessity for tailored management strategies based on the type of reflex seizures.

Photo-Dependent Reflex Seizures-A Scoping Review with Proposal of Classification

Children and adolescents are the largest at-risk group for the appearance of reflex seizures or epilepsy syndromes with a photoparoxysmal response. The aim of this study was to present an overview of the literature regarding photo-dependent reflex seizures. Epilepsy with seizures provoked by intermittent light stimulation is a distinct group of epilepsies; therefore, we focused on reflex seizures provoked by different factors whose common feature is the patient's response to intermittent photic stimulation. A qualitative search of PubMed/MEDLINE, Scopus, EBSCO, and Cochrane Library electronic databases for selected terms was carried out for scientific articles published up to May 2020 outlining the outcomes of control, observational, and case studies. This scoping review was developed and followed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. The review of the qualitative evidence for the synthesis of photosensitive epilepsy allowed us to distinguish the following categories: light-induced seizures and light-deprived seizures. Differentiating between intermittent photic stimulation-related epilepsy syndromes and seizures is essential in order to determine the length of appropriate treatment. Photo-dependent reflex seizures make up the majority of this type of disorder among reflex seizures. Since there are many seizures provoking factors in the world around us, it is important to distinguish amongst them in order to be able to protect the patient exposed to this factor. It is recommended that the photostimulation procedure be performed during a routine electroencephalogram study.

Visually sensitive seizures: An updated review by the Epilepsy Foundation

Light flashes, patterns, or color changes can provoke seizures in up to 1 in 4000 persons. Prevalence may be higher because of selection bias. The Epilepsy Foundation reviewed light-induced seizures in 2005. Since then, images on social media, virtual reality, three-dimensional (3D) movies, and the Internet have proliferated. Hundreds of studies have explored the mechanisms and presentations of photosensitive seizures, justifying an updated review. This literature summary derives from a nonsystematic literature review via PubMed using the terms "photosensitive" and "epilepsy." The photoparoxysmal response (PPR) is an electroencephalography (EEG) phenomenon, and photosensitive seizures (PS) are seizures provoked by visual stimulation. Photosensitivity is more common in the young and in specific forms of generalized epilepsy. PS can coexist with spontaneous seizures. PS are hereditable and linked to recently identified genes. Brain imaging usually is normal, but special studies imaging white matter tracts demonstrate abnormal connectivity. Occipital cortex and connected regions are hyperexcitable in subjects with light-provoked seizures. Mechanisms remain unclear. Video games, social media clips, occasional movies, and natural stimuli can provoke PS. Virtual reality and 3D images so far appear benign unless they contain specific provocative content, for example, flashes. Images with flashes brighter than 20 candelas/m2 at 3-60 (particularly 15-20) Hz occupying at least 10 to 25% of the visual field are a risk, as are red color flashes or oscillating stripes. Equipment to assay for these characteristics is probably underutilized. Prevention of seizures includes avoiding provocative stimuli, covering one eye, wearing dark glasses, sitting at least two meters from screens, reducing contrast, and taking certain antiseizure drugs. Measurement of PPR suppression in a photosensitivity model can screen putative antiseizure drugs. Some countries regulate media to reduce risk. Visually-induced seizures remain significant public health hazards so they warrant ongoing scientific and regulatory efforts and public education.

Case report: A relevant misdiagnosis: Photosensitive epilepsy mimicking a blinking tic

Blinking in children is most frequently a functional and transient symptom. Nonetheless, sometimes it is the first clinical manifestation of a neurological disorder. The differential diagnosis between voluntary actions, tics and other neurological disorders among which seizures may be challenging and misdiagnosis is common. A 6-year-old girl in good health was admitted for a recent history of bilateral eye blinking. Blinking did not interfere with the girl's activities. The patients reported that blinking seemed to be triggered by sunlight exposure and that girl sometimes seemed to be attracted by the sunlight. Ophthalmological diseases had been already excluded. The girl was addressed to our hospital for neurological consultation, as tic disease was considered the most probable hypothesis. Neurological examination was negative. In the field of differential diagnosis of photosensitive abnormal eyelid movements, the hypothesis of seizures was explored and further investigated with a video-EEG recording with light stimulation. This exam demonstrated a photoparoxysmal response (PPR) to intermittent photic stimulation with appearance on EEG of bilateral spike and polyspike waves associated with eyelid jerks. This girl suffers from generalized epilepsy with photosensitivity. Photosensitivity is a common feature of many epilepsy syndromes, mainly occurring in children and adolescents. To control the seizures, it is essential to avoid the triggering stimulus, by wearing specific glasses. Additional antiseizures treatment is often necessary, at first with valproate and levetiracetam, and ethosuximide, lamotrigine, and benzodiazepines as the second choice. Overlapping phenomenology of seizures and movement disorders is well known in paediatric clinical practice. Moreover, epilepsy and movement disorder may coexist, mainly in children. Seizures with semeiology limited to eye motor manifestations may mimic functional blinking, tics, and other motor events frequently observed in childhood. Differentiating seizures from other non-epileptic paroxysmal movements may be challenging and specialist evaluation is needed for proper treatment and prognostic counselling.

Contribution of intermittent photic stimulation to routine EEG

OBJECTIVE

Intermittent photic stimulation (IPS) is an activation procedure performed during electroencephalography (EEG) to detect photosensitive patients. This procedure is recommended in routine EEGs but the benefit of IPS in the general population is not clearly ascertained.

METHODS

We retrospectively analyzed 7683 EEGs of patients referred for a routine EEG to the Clinical Physiology Department of Lariboisière hospital, mainly from the emergency ward and the department of neurology, not specifically involved in epilepsy. All EEGs were performed with a standardized protocol. Photic driving response, photomyoclonic response and photoparoxysmal response (PPR) were specifically collected. A correlation analysis was performed between the response induced by IPS, demographical and clinical data, and current treatment or recreational drug use.

RESULTS

Median age was 56.4 years (41.7-71.2); 3,042 (39.6%) of patients were female; 1,208 patients (15.7%) had a past medical history of epilepsy. Photic driving response occurred in 67 EEGs (0.9%), and PPR in 6 EEGs (0.1%), all with a known history of epilepsy. Thus 0.5% (6/1,208) of epilepsy patients had a PPR. Photomyoclonic responses were not observed. Juvenile myoclonic epilepsy was the only factor associated with the presence of PPR (RR=75.26 [11.82-479.21]). PPR was not associated with clinical symptoms or seizures. There was no correlation with the type of treatment or recreational drug use.

CONCLUSIONS

Our results confirm that responses to IPS are rare in adult patients and especially PPR. Moreover, all patients with a PPR had a known previous history of epilepsy. These results question the benefit of IPS in adult patients with no history of epilepsy.

Reflex Epilepsy

Reflex seizures (RS) are epileptic events that are objectively and consistently elicited in response to a specific afferent stimulus or by an activity of the patient. The specific stimulus can be a variety of heterogenous intrinsic or extrinsic factors, ranging from the simple to the complex, such as flashing lights or reading a book. These seizures can take a variety of forms, comprising either general or focal onset, with or without secondary generalization. Reflex epilepsies (RE) are classified as a specific syndrome in which all epileptic seizures are precipitated by sensory stimuli. The few designated RE include idiopathic photosensitive occipital lobe epilepsy, other visual sensitive epilepsies, primary reading epilepsy, and startle epilepsy. RS that occurs within other focal or generalized epilepsy syndromes that are associated with distinct spontaneous seizures are classified by the overarching seizure type. Most patients experience spontaneous seizures along with their provoked events. RS originate from stimulation of functional anatomic networks normally functioning for physiological activities, that overlap or coincide with regions of cortical hyperexcitability. Generalized RS typically occur within the setting of IGEs and should be considered as focal seizures with quick secondary generalization via cortico-cortical or cortico-reticular pathways. In aggregate, activation of a critical neuronal mass, supported and sustained by cortico-subcortical and thalamocortical pathways eventually result in a seizure. Treatment includes antiseizure medication, commonly valproate or levetiracetam, along with lifestyle modifications, and when amenable, surgical intervention. High clinical suspicion and careful history taking must be employed in all epilepsy patients to identify reflex triggers.

Photoparoxysmal response and its characteristics in a large EEG database using the SCORE system

OBJECTIVE

To characterize photoparoxysmal EEG response (PPR) using a standardized protocol of intermittent photic stimulation (IPS) and standardized definitions for PPR, classified into six types.

METHODS

Using the SCORE system (Standardized Computer-Based Organized Reporting of EEG) we prospectively built a large database of standardized EEG annotations. In this study, we extracted the features related to PPR from the structured dataset consisting of 10,671 EEG recordings with IPS, from 7,188 patients.

RESULTS

The standardized IPS protocol elicited PPR in 375 recordings (3.5%), in 288 patients (4%), with a preponderance among young (11-20 years) and female patients (67%). PPR was persistent in patients with multiple recordings. The most frequent type of PPR was activation of preexisting epileptogenic area (58%), followed by generalized-PPR limited to the stimulus train (22%). We could not find any recording with self-sustained posterior response. Seizures were elicited in 27% of patients with PPR, most often myoclonic seizures and absences, in patients with self-sustained generalized PPR.

CONCLUSIONS

The most common type of PPR was accentuation of preexisting epileptogenic area. Self-sustained posterior response could not be documented. Self-sustained generalized-PPR had the highest association with seizures.

SIGNIFICANCE

Using standardized stimulation protocol and definitions for PPR types, IPS provides high diagnostic yield.

Seizure triggered by flicker electroretinogram in a patient with no history of epilepsy

Purpose

It is well known that repetitive flash stimulation may trigger seizures in susceptible individuals. Nevertheless, reports of such incidents occurring during recording of a flash electroretinogram (ERG) are extremely rare. Here, we describe the case of a photic-induced seizure triggered during an ERG recording in the absence of a history of epilepsy or other paroxysmal events.

Methods

A 14-year-old male patient presented with reduced visual acuity and impaired mesopic vision. Ophthalmological exams confirmed the patient’s complaints but were inconclusive as to the underlying pathophysiology. An ERG recording was performed, during which the 30-Hz flicker stimulus triggered a seizure.

Results

The ERG was essentially normal, with the exception of a 7-Hz rhythm superimposed onto the flicker ERG response that was recorded when the seizure developed.

Conclusions

The present case highlights the possibility that the 30-Hz ERG flash stimulus triggers a seizure in patients with no previous paroxysmal events. Literature evidence suggests that the likelihood of such an incident could be reduced by stimulating monocularly.

Light-emitting-diode and Grass PS 33 xenon lamp photic stimulators are equivalent in the assessment of photosensitivity: Clinical and research implications

The assessment of the effect of photic stimulation is an integral component of an EEG exam and is especially important in patients referred for ascertained or suspected photosensitivity with or without a diagnosis of epilepsy. A positive test result relies on eliciting a specific abnormality defined as the "photoparoxysmal response". Reliability of this assessment is strongly influenced by technical and procedural variables, a critical one represented by the physical properties of the stimulators used. Established clinical norms are based on data acquired with the "gold-standard" Grass PS stimulators. These are no longer commercially available and have been replaced by stimulators using light emitting diode (LED) technology. To our knowledge no comparative study on their efficacy has been conducted. To address this gap, we recruited 39 patients aged 5-54 years, referred to two specialized centers with confirmed of suspected diagnosis of photosensitive epilepsy or generalized epilepsy with photosensitivity in a prospective randomized single-blind cross-over study to compare two commercially available LED-bases stimulation systems (FSA 10® and Lifeline® stimulators) against the Grass PS 33 xenon lamp device. Our findings indicate that the LED systems tested are equivalent to the Grass stimulator both in identifying the PPR in affected individuals.

Concern of Photosensitive Seizures Evoked by 3D Video Displays or Virtual Reality Headsets in Children: Current Perspective

This review assesses the risk of a photic-induced seizure in a child during viewing of 3D (binocular 3 dimensional, stereoscopic) movies or games, either on standard video displays or when wearing a virtual reality (VR) headset. Studies published by pediatric epilepsy experts emphasize the low risk of 3D viewing even for children with known photosensitive epilepsy (PSE). The low incidence of PSE is noteworthy because the number of hours devoted to 2D or 3D screen viewing and/or VR headset use by children worldwide has increased markedly over the last decade. The medical literature does not support the notion that VR headset use poses a risk for PSE.

Reflex epileptic features in patients with focal epilepsy of unknown cause

OBJECTIVES

There is a gap of knowledge regarding reflex seizures in patients with focal epilepsy of unknown cause (FEUC). We aimed to evaluate the prevalence, demographic and clinical characteristics of reflex seizures in patients with FEUC to provide an insight to the underlying ictogenic mechanisms and to draw attention to this important but under-investigated topic.

PATIENTS AND METHODS

After carefully questioning for reflex triggers, 186 patients diagnosed according to ILAE criteria and followed-up for a minimum of 5 years were included. The demographic and clinical properties as well as electrophysiological and neuroimaging data of these patients were reevaluated and compared to the patients without reflex seizures.

RESULTS

The reflex seizure rate was 6.5 % in patients with FEUC. Patients with reflex features had lower monotherapy rates (p = 0.005) and higher major depression rates (p = 0.001) than patients without reflex features. The distribution of the patients according to their reflex triggers were as follows: hot-water induced (n = 3, 25 %), photosensitive (n = 2, 16.7 %), eating- induced (n = 2, 16.7 %), musicogenic (n = 2, 16.7 %), startle induced (n = 2, 16.7 %) and both musicogenic and startle type (n = 1, 8.3 %) respectively. The drug resistance rate of patients with reflex seizures was 25 % (n = 3). One patient with drug resistant reflex seizures showed benefit from epilepsy surgery and became seizure-free during last 3 years of follow-up.

CONCLUSION

A careful and thoroughly history taking specifically questioning and focusing on seizure inducing factors in patients with FEUC is needed to confirm the presence of reflex seizures in patients with FEUC, who had higher rates of polytherapy and major depression. Elaborative evaluation of reflex features in FEUC might contribute to effective seizure control, ensure new therapeutic approaches, enlighten the obscurity and the resulting anxiety of having a diagnosis of FEUC in epilepsy patients.

Photosensitive epilepsy and photosensitivity of patients with possible epilepsy in Chinese Han race: A prospective multicenter study

Photosensitive is probably caused by multiple factors including gender, familiar, etc. We aim to study the clinical and EEG features of Chinese Han patients with photosensitivity. A total of 5482 consecutive patients with possible epilepsy from 3 center in China. Of the 73 patients with PPR to IPS, 48 were female. 69.9% patients were evoked by frequency ranged 8 Hz-25 Hz, with accompanying seizures in 13 patients. 6 of 9 patients with eyes closure sensitivity experienced epileptic seizures during IPS. We found some new features: 1) The patients with eyes closure sensitivity apt to experience electro-clinical seizures provoked by IPS; 2) Female epilepsy patients with PPR and ECS maybe difficult to be seizure free. Preventive measures for related seizures should be performed to the patients with generalized PPR, upper threshold evoking frequency, and eyes closure sensitivity when they received the IPS.

Reflex epilepsy: triggers and management strategies

Reflex epilepsies (REs) are identified as epileptic seizures that are consistently induced by identifiable and objective-specific triggers, which may be an afferent stimulus or by the patient's own activity. RE may have different subtypes depending on the stimulus characteristic. There are significant clinical and electrophysiologic differences between different RE types. Visual stimuli-sensitive or photosensitive epilepsies constitute a large proportion of the RE and are mainly related to genetic causes. Reflex epilepsies may present with focal or generalized seizures due to specific triggers, and sometimes seizures may occur spontaneously. The stimuli can be external (light flashes, hot water), internal (emotion, thinking), or both and should be distinguished from triggering precipitants, which most epileptic patients could report such as emotional stress, sleep deprivation, alcohol, and menstrual cycle. Different genetic and acquired factors may play a role in etiology of RE. This review will provide a current overview of the triggering factors and management of reflex seizures.

Genetic and neurodevelopmental spectrum of SYNGAP1-associated intellectual disability and epilepsy

OBJECTIVE

We aimed to delineate the neurodevelopmental spectrum associated with SYNGAP1 mutations and to investigate genotype-phenotype correlations.

METHODS

We sequenced the exome or screened the exons of SYNGAP1 in a total of 251 patients with neurodevelopmental disorders. Molecular and clinical data from patients with SYNGAP1 mutations from other centres were also collected, focusing on developmental aspects and the associated epilepsy phenotype. A review of SYNGAP1 mutations published in the literature was also performed.

RESULTS

We describe 17 unrelated affected individuals carrying 13 different novel loss-of-function SYNGAP1 mutations. Developmental delay was the first manifestation of SYNGAP1-related encephalopathy; intellectual disability became progressively obvious and was associated with autistic behaviours in eight patients. Hypotonia and unstable gait were frequent associated neurological features. With the exception of one patient who experienced a single seizure, all patients had epilepsy, characterised by falls or head drops due to atonic or myoclonic seizures, (myoclonic) absences and/or eyelid myoclonia. Triggers of seizures were frequent (n=7). Seizures were pharmacoresistant in half of the patients. The severity of the epilepsy did not correlate with the presence of autistic features or with the severity of cognitive impairment. Mutations were distributed throughout the gene, but spared spliced 3' and 5' exons. Seizures in patients with mutations in exons 4-5 were more pharmacoresponsive than in patients with mutations in exons 8-15.

CONCLUSIONS

SYNGAP1 encephalopathy is characterised by early neurodevelopmental delay typically preceding the onset of a relatively recognisable epilepsy comprising generalised seizures (absences, myoclonic jerks) and frequent triggers.

Photic stimulation during electroencephalography: Efficacy and safety in an unselected cohort of patients referred to UK neurophysiology departments

PURPOSE

To determine efficacy and safety of photic stimulation (PS) during electroencephalography (EEG) in a large group of adult and paediatric patients.

METHODS

A prospective multicentre National Service Evaluation was performed organised by the joint audit committee of the two UK professional organisations (Association of Neurophysiological Scientists and British Society for Clinical Neurophysiology). Questionnaires about every EEG performed in the two-month study period were completed contemporaneously by physiologists at the time of the recording-reporting. The occurrence during PS of photoparoxysmal responses (PPRs), seizures and psychogenic non-epileptic attacks was noted from the EEG trace and contemporary clinical observation backed up by the video that was synchronised with the EEG. 5383 patients investigated with EEG and PS, mostly for possible epilepsy, were included in the study.

RESULTS

Seventy nine patients (1.5%) had a generalised PPR elicited by PS having had no generalised epileptiform discharges previously in the EEG. Thirty nine patients (0.7%) had seizures provoked by PS including two (0.04%) who had a generalised tonic clonic seizure (GTCS). Forty nine patients (0.9%) had non-epileptic attacks provoked by PS. Thus PS yielded potentially useful information (PPRs, seizures or non-epileptic attacks) in 167/5383 (3.1%) of patients. In a subset of 122/5383 (2.3%), PS provided the only useful information captured within the EEG.

CONCLUSION

PS contributes to the diagnosis of epilepsy and non-epileptic attack disorder in 3.1% of patients. It is a safe technique which produces GTCSs in only 0.04% patients. We conclude that PS is a moderately useful activation technique in diagnostic EEG, where the potential benefits out-weigh the risks; this information may assist the informed consent process.

Visual-Sensitive Epilepsies: Classification and Review

Photosensitivity, photosensitive seizures, and photosensitive epilepsy are discussed. The International League against Epilepsy has suggested the term “visual-sensitive” replace “photosensitive”. Visual-sensitive seizures may be more common than is realized. A classification for visual-sensitive epilepsies is presented. Chromosomal and DNA testing may help to refine the classification further. A standardized approach for neurophysiologic testing, such as that proposed by European experts, is recommended. These steps should promote evidenced-based management for this group of disorders.

Generalized versus partial reflex seizures: a review

In this review we assess our currently available knowledge about reflex seizures with special emphasis on the difference between "generalized" reflex seizures induced by visual stimuli, thinking, praxis and language tasks, and "focal" seizures induced by startle, eating, music, hot water, somatosensory stimuli and orgasm. We discuss in particular evidence from animal, clinical, neurophysiological and neuroimaging studies supporting the concept that "generalized" reflex seizures, usually occurring in the setting of IGE, should be considered as focal seizures with quick secondary generalization. We also review recent advances in genetic and therapeutic approach of reflex seizures.

Pattern sensitivity: a missed part of the diagnosis

RATIONALE

Pattern sensitivity can be diagnosed by presenting a series of visual patterns to the subject in the electroencephalography (EEG) laboratory; however, testing for pattern sensitivity is not routinely done during EEG recording. This work aimed to highlight the incidence of pattern sensitivity among patients referred for routine EEG recording during a 1-year period, identifying the cause of referral, diagnosis, and the characteristics of pattern-sensitive patients.

METHODS

All patients aged 4 years and older who were referred for routine EEG during a 12-month period and had no motor or visual impairment were enrolled in the study. Intermittent photic stimulation and pattern sensitivity were tested for each case. Pattern sensitivity was tested by scanning three different rhythmically moving patterns at reading distance with the patient seated in an illuminated room. A pattern evoking a paroxysmal response was reintroduced after exposure to a blank white card to confirm the findings.

RESULTS

Two hundred twenty-eight patients were studied; twelve patients (5.26%) had pattern sensitivity and their ages ranged from 5 to 12 years. Eight of these patients (66.7%) were referred for seizure disorders, two were referred with the diagnosis of migraine, one with headache and poor scholastic performance and one with recurrent attacks of dizziness for investigation. Seven of the twelve patients (58.3%) had a previous EEG done without testing for pattern sensitivity. Five patients (41.6%) had positive family history for epilepsy, three (25%) for migraine, and two (16.6%) for migraine and epilepsy. Two patients (16.6%) had pattern sensitivity without photosensitivity. Pattern stimulation provoked epileptiform discharges in eight patients (66.6%), focal discharges in one, and unilateral build-up of posterior discharge in three.

CONCLUSION

Diagnosis of pattern sensitivity is often missed as it is not routinely tested for during EEG recording. The result of the study challenges the concept of a consistent association between photosensitivity and pattern sensitivity; it also raises questions about the incidence of pattern sensitivity among children who do not suffer from epilepsy and in particular those with migraine, headache and scholastic difficulties. Further studies are therefore needed to clarify the phenotypic spectrum of this EEG trait.

The photoparoxysmal response: the probable cause of attacks during video games

Photic stimulation is part of a typical EEG in most countries, especially to check on the photoparoxysmal response (PPR). Interest in this response was enhanced in 1997 when hundreds of Japanese children had attacks while viewing a TV cartoon called "Pokemon." The overall prevalence of the PPR among patients requiring an EEG is approximately 0.8%, but 1.7% in children and 8.87% in patients with epilepsy, more often in Caucasians and females. Autosomal dominant inheritance is indicated, and this response is seen especially at the wavelength of 700 nm or at the flicker frequency of 15-18 Hz. The PPR extending beyond the stimulus carries no increased risk of seizures. Prognosis is generally good, especially after 20 years of age. Attention to PPR has been increased with the advent of video games, and the evoked seizures from these games are likely a manifestation of photosensitive epilepsy. Drug therapy has emphasized valproic acid, but Levetiracetam has also been successful in eliminating the PPR.

Epilepsy and videogames

Since the first case of videogame (VG) epilepsy was reported in 1981, many cases of seizures triggered by VGs were reported, not only in photosensitive, but also in non-photosensitive children and adolescents with epilepsy. We provide an overview of the literature with overall conclusions and recommendations regarding VG playing. Specific preventive measures concerning the physical characteristics of images included in commercially available VGs (flash rate, choice of colors, patterns, and contrast) can lead in the future to a clear decrease of this problem. In addition to the positive effect of such measures, the collaborative studies performed in France and in the rest of Europe have stressed the importance of a safe distance to the screen of > or = 2 m, and the less provocative role of 100-Hz screens.

Photosensitivity: the magnitude of the problem

Very few studies of photosensitivity or visual sensitive epilepsy could be called epidemiologic in the strict sense, that is, giving well-based incidence and prevalence rates of a well-defined clinical and electroencephalographic syndrome or group of syndromes. The available data suggest that photosensitivity is rare in the population as a whole, with an annual incidence rate around one case per 100,000 population. The incidence goes up to almost six per 100,000 in the late adolescent period, the age group at the highest risk. Well-established concepts, such as statements that one in 4,000 of the general population or that 10% of all epilepsy patients would be photosensitive, should be reevaluated. The more likely figures are a lifetime prevalence of one in 10,000 in the general population, perhaps as low as 2%, of the epilepsy population. Further epidemiologic studies, sensu strictu, are warranted to settle the basic question of the real incidence and prevalence of photoparoxysmal responses (PPRs) and epilepsy with seizures provoked by visual stimuli in the community.

Photosensitivity in Idiopathic Generalized Epilepsies

Photosensitivity is an abnormal visual sensitivity of the brain in reaction to flickering light sources or patterns and is expressed in the electroencephalogram as generalized spike-and-wave discharge and in more susceptible individuals as clinical seizures. The most common types of seizures are generalized tonic-clonic, followed by myoclonic and absence. The photosensitive epilepsies are classified as pure photosensitive, where seizures occur only with the flickering light source/pattern or during intermittent photic stimulation (IPS) in the laboratory, and epilepsy with photosensitivity, where spontaneous seizures also occur. Positive response to IPS in idiopathic epilepsy syndromes, which are included in the International Classification or are in development, is reported to range from 7.5% in juvenile absence epilepsy to 100% in pure photosensitive epilepsy. The treatment of photosensitivity and pure photosensitive epilepsy with rare seizures includes general and specific protective measures. For most patients, however, combination treatment with antiepileptic drugs is necessary. Valproic acid monotherapy has a success rate of 73-86%. Levetiracetam appears to be a new alternative therapeutic option. Clobazam, lamotrigine, ethosuximide, and topiramate also have been recommended as second-choice therapies.

Human photosensitivity: from pathophysiology to treatment

Photosensitivity is a condition detected on the electroencephalography (EEG) as a paroxysmal reaction to Intermittent Photic Stimulation (IPS). This EEG response, elicited by IPS or by other visual stimuli of daily life, is called Photo Paroxysmal Response (PPR). PPRs are well documented in epileptic and non-epileptic subjects. Photosensitivity rarely in normal individuals evolves into epilepsy. Photosensitive epilepsy is a rare refex epilepsy characterized by seizures in photosensitive individuals. The development of modern technology has increased the exposition to potential seizure precipitants in people of all ages, but especially in children and adolescents. Actually, videogames, computers and televisions are the most common triggers in daily life of susceptible persons. The mechanisms of generation of PPR are poorly understood, but genetic factors play an important rule. The control of visually induced seizures has, generally a good prognosis. In patients known to be visually sensitive, avoidance of obvious source and stimulus modifications are very important and useful to seizure prevention, but in the large majority of patients with epilepsy and photosensitivity antiepileptic drugs are needed.

Photic- and pattern-induced seizures: a review for the Epilepsy Foundation of America Working Group

PURPOSE

This report summarizes background material presented to a consensus conference on visually provoked seizures, convened by the Epilepsy Foundation of America.

METHODS

A comprehensive review of literature was performed.

RESULTS

Photosensitivity, an abnormal EEG response to light or pattern stimulation, occurs in approximately 0.3-3% of the population. The estimated prevalence of seizures from light stimuli is approximately 1 per 10,000, or 1 per 4,000 individuals age 5-24 years. People with epilepsy have a 2-14% chance of having seizures precipitated by light or pattern. In the Pokemon cartoon incident in Japan, 685 children visited a hospital in reaction to red-blue flashes on broadcast television (TV). Only 24% who had a seizure during the cartoon had previously experienced a seizure. Photic or pattern stimulation can provoke seizures in predisposed individuals, but such stimulation is not known to increase the chance of subsequent epilepsy. Intensities of 0.2-1.5 million candlepower are in the range to trigger seizures. Frequencies of 15-25 Hz are most provocative, but the range is 1-65 Hz. Light-dark borders can induce pattern-sensitive seizures, and red color also is a factor. Seizures can be provoked by certain TV shows, movie screen images, video games, natural stimuli (e.g, sun on water), public displays, and many other sources.

CONCLUSIONS

Recommendations on reducing risk of seizures have been developed by agencies in the United Kingdom, Japan, and the International Telecommunications Union, affiliated with the United Nations. The Epilepsy Foundation of America has developed a consensus of medical experts and scientists on this subject, reported in an accompanying work.

Intermittent photic stimulation as an activation method for electroencephalographic screening of aircrew applicants

Disqualifying criteria for aircrew in Europe (JAR-FCL 3) are, besides a diagnosis of epilepsy after the age of 5 and a history of episode(s) of disturbance of consciousness, epileptiform paroxysmal electroencephalographic abnormalities and focal slow waves. Intermittent photic stimulation (IPS) provokes in about 0.5% of healthy subjects (range 0-2%) a photoparoxysmal response and is most often the only abnormality (70-90%). The literature is scarce and shows great diversity in methodology. Standardized IPS with simultaneous video will not only allow collection of sufficient data for proper epidemiological studies, but can also reveal clinical and often unnoticed or misinterpreted signs and symptoms like myoclonia, loss of consciousness, and occipital seizures with visual auras. The pilot (sleep deprivation, strong sunlight) and the traffic controller (stress, monitors) are more prone to visually induced seizures. Furthermore, the increasing exposure to potentially seizure-triggering visual stimuli might have its impact in a more indirect or cumulative way.

The acute effect of music on interictal epileptiform discharges

This study was a prospective, randomized, single-blinded, crossover, placebo-controlled, pilot clinical trial investigating the effect of Mozart's Sonata for Two Pianos (K448) on the frequency of interictal epileptiform discharges (IEDs) from the EEGs of children with benign childhood epilepsy with centrotemporal spikes, or "rolandic" epilepsy. The goal was to demonstrate decreased frequency of IEDs with exposure to K448. Four subjects were recruited and 4-hour awake EEG recordings performed. IED frequency per minute was averaged over each of three epochs per hour. Mean IED count per epoch, standard deviations, and variance were calculated. Only complete waking epochs were analyzed. Two subjects demonstrated sufficient waking IEDs for statistical analysis, consisting of three epochs of K448-related effects. Significant decreases in IEDs per minute (33.7, 50.6, and 33.9%) were demonstrated comparing baseline with exposure to K448, but not to control music (Beethoven's Für Elise).

Photosensitivity and epilepsy

Photosensitive epilepsy is a well-known condition characterized by seizures in patients who show photoparoxysmal responses on electroencephalography (EEG) elicited by intermittent photic stimulation. Photoparoxysmal responses can be defined as epileptiform EEG responses to intermittent photic stimulation or to other visual stimuli of everyday life and are frequently found in nonepileptic children. The modern technologic environment has led to a dramatic increase in exposure to potential trigger stimuli; nowadays, television and video games are among the most common triggers in daily life. There is ample evidence for genetic transmission of photoparoxysmal responses; systematic family studies have provided data for an autosomal dominant mode of inheritance with age-dependent penetrance for photosensitivity. The age of maximum penetrance is between 5 and 15 years. The prognosis for control of seizures induced by visual stimulation is generally very good. The large majority of patients do not need anticonvulsant therapy, but, when needed, the drug of choice is valproate. Stimulus avoidance and stimulus modification can be an effective treatment in some patients and can sometimes be combined with antiepileptic drug treatment.

Risk factors in adolescence: the case of gambling, videogame playing, and the internet

It has been noted that adolescents may be more susceptible to pathological gambling. Not only is it usually illegal, but it appears to be related to high levels of problem gambling and other delinquent activities such as illicit drug taking and alcohol abuse. This paper examines risk factors not only in adolescent gambling but also in videogame playing (which shares many similarities with gambling). There appear to be three main forms of adolescent gambling that have been widely researched. Adolescent gambling activities and general risk factors in adolescent gambling are provided. As well, the influence of technology on adolescents in the form of both videogames and the Internet are examined. It is argued that technologically advanced forms of gambling may be highly appealing to adolescents.

Physiology of Human Photosensitivity

Human epileptic photosensitivity has been studied in several ways. (a) Visual stimulation that resembles the stimulation normally responsible for seizures, such as that from televisions or videogames, both of which typically use cathode ray tubes in which the display is created in a flickering pattern. Such stimulation is often rendered yet more epileptogenic by programmes with content that also involves flashing or patterned material. (b) Elementary visual stimuli that enable inferences to be drawn concerning the physiological trigger mechanisms. The topographic distribution of epileptiform EEG activity in response to such stimuli has complemented this approach, leading to the inference that the trigger is cortical and requires sychronised mass action of neurons. (c) Stimuli that avoid paroxysmal EEG activity and permit an investigation of the subepileptic response to visual stimuli, using the evoked potential. This has revealed abnormalities in the cortical mechanisms that control the response to strong visual stimulation.

Can police car colored flash light induce electroencephalographic discharges and seizures?

AIM

To explore the epileptogenic potential of a newly introduced police car flash light device (930 Heliobe Lightbar).

METHODS

A 930 Heliobe Lightbar was installed in the EEG laboratory. Thirty patients with known epilepsy, 30 subjects with chronic headache who were otherwise healthy and 15 healthy volunteers were examined.

RESULTS

All the subjects signed an informed consent and underwent an EEG during which photostimulation was performed with the standard stroboscope and later with the Police lightbar. In all 75 examined the lightbar did not induce clinical or electrographic seizures. In a single patient with epilepsy the lightbar enhanced epileptiform activity induced by standard photic stimulation.

CONCLUSION

In this study the new Police lightbar was found to be non-epileptogenic.

Study on photo-pattern sensitivity in patients with electronic screen game-induced seizures (ESGS): effects of spatial resolution, brightness, and pattern movement

PURPOSE

With the ever-increasing popularity of computers, electronic screen game-induced seizure (ESGS) is beginning to pose a serious social problem. To elucidate the pathophysiology of ESGS, with the ultimate goal of prevention, we have been studying photo-pattern sensitivity in detail with a pattern-stimulation test using a CRT (cathode ray tube) display. This method is referred to as the "CRT-pattern test."

METHODS

We studied 17 patients brought to our department for evaluation of ESGS. EEG responses were recorded during exposure to various patterns consisting of three elements: spatial resolution, brightness perception, and pattern-movement recognition displayed on a CRT monitor. Photo-paroxysmal response (PPR) frequencies were compiled for each stimulation.

RESULTS

PPR was induced by the CRT-pattern test in nine of the 17 cases. In four cases, PPR induction was obtained only after introducing CRT-pattern tests in addition to standard intermittent photic stimulation (IPS). The rate of PPR induction differed according to the type of pattern, spatial frequency, and pattern-reversal frequency. However, neither the clarity of the edges of a pattern nor changes in the brightness of a pattern element had any effect on the rate of PPR induction. With the exception of a few subjects, the stimulation caused by pattern movement was not effective in eliciting PPR. Six cases in whom spatial resolution was involved showed occipital dominance in PPR provocation, and three in whom brightness perception and pattern movement recognition was involved showed frontal dominance.

CONCLUSIONS

The CRT-pattern test is useful for identifying patients with photosensitivity among patients considered to have incidental or nonphotosensitive seizures unresponsive to standard IPS. Patients with ESGS caused by photosensitivity can be divided into two groups: those with occipital dominance for PPR provocation, in whom spatial resolution is involved; and another group with frontal dominance, in whom brightness perception and pattern-movement recognition (or possibly perception of colors) are involved.

Photogenic partial seizures

PURPOSE

To establish the incidence and symptoms of partial seizures in a cohort of patients investigated on account of known sensitivity to intermittent photic stimulation and/or precipitation of seizures by environmental visual stimuli such as television (TV) screens or computer monitors.

METHODS

We report 43 consecutive patients with epilepsy, who had exhibited a significant EEG photoparoxysmal response or who had seizures precipitated by environmental visual stimuli and underwent detailed assessment of their photosensitivity in the EEG laboratory, during which all were questioned concerning their ictal symptoms.

RESULTS

All patients were considered on clinical grounds to have an idiopathic epilepsy syndrome. Twenty-eight (65%) patients reported visually precipitated attacks occurring initially with maintained consciousness, in some instances evolving to a period of confusion or to a secondarily generalized seizure. Visual symptoms were most commonly reported and included positive symptoms such as coloured circles or spots, but also blindness and subjective symptoms such as "eyes going funny." Other symptoms described included nonspecific cephalic sensations, deja-vu, auditory hallucinations, nausea, and vomiting. No patient reported any clear spontaneous partial seizures, and there were no grounds for supposing that any had partial epilepsy excepting the ictal phenomenology of some or all of the visually induced attacks.

CONCLUSIONS

These findings provide clinical support for the physiological studies that indicate that the trigger mechanism for human photosensitivity involves binocularly innervated cells located in the visual cortex. Thus the visual cortex is the seat of the primary epileptogenic process, and the photically triggered discharges and seizures may be regarded as partial with secondary generalization.

[Photosensitive epilepsy and television epilepsy]

Photosensitivity is defined by the appearance of occipital or more diffuse electroencephalographic spikes and waves induced by intermittent light stimulation (ILS), particular patterns, TV-watching, and video games. Photosensitivity is a genetic characteristic. Only the diffuse spikes and waves induced by ILS are correlated with epilepsy. Pure photogenic epilepsy is characterized by seizures which are only visually induced, usually by watching TV. Video games sometimes add a trigger effect due to slowly moving patterns or intense brightness. Several epileptic syndromes are associated with a photosensitivity with or without visually-induced seizures, mainly generalized idiopathic epilepsy.

Brain activation during intermittent photic stimulation: a [15O]-water PET study on photosensitive epilepsy

PURPOSE

Intermittent photic stimulation (IPS) is an activation procedure used during electroencephalogram (EEG) recording to elicit paroxysmal discharges in individuals with photosensitivity. Specific responses on EEG recording may be provoked by IPS at different frequencies of flickering in normal individuals and in patients with photosensitive epilepsy.

METHODS

Changes in regional cerebral blood flow (rCBF) were studied during IPS in two groups of subjects by using [15O]-water positron emission tomography (PET): a control group consisting of eight healthy adults with photic driving response during IPS on EEG recording (mean age, 25 +/- 10.5 years) without history of neurologic or psychiatric abnormalities and a patient group consisting of four adults (mean age, 33 +/- 7.5 years) with history of photosensitive epilepsy. [15O]-water PET scanning with concomitant EEG monitoring was performed during baseline and IPS at 4-, 14-, and 30-Hz frequencies.

RESULTS

The control group showed photic driving response at 14-Hz IPS frequency. The patient group showed photoparoxysmal response at 14 and 30 Hz, but not at 4 Hz. Changes in rCBF were determined by means of statistical parametric mapping. Increases in rCBF in occipital cortex (Brodmann's areas 17, 18, and 19) were observed in both groups. In addition, during photic driving responses, the control group showed rCBF increases in the insula and in the thalamus, on the right side. The patient group showed a significant rCBF increase in the hypothalamic region inferior to the left caudate nucleus during photoparoxysmal response. This activation was not found in the control group. Increased rCBF also was observed in the patient group in the head of the left caudate nucleus, in the left hippocampus, and in left insula during IPS without photoparoxysmal response. No activations in these regions were observed during photoparoxysmal response.

CONCLUSIONS

These data may indicate involvement of the hypothalamus in photosensitive epilepsy and may suggest a modulatory function of the caudate nucleus, which might be associated with an inhibition of epileptic discharges during IPS in patients with photosensitive epilepsy.

Low-luminance visual stimuli compared with stroboscopic IPS in eliciting PPR in photosensitive patients

PURPOSE

Photosensitivity is thought to play the most important role in the genesis of electronic screen games induced seizures (ESGIS). To elicit photoparoxysmal response (PPR) effectively, we performed EEG activation by low-luminance visual stimuli: 20 cd/m2 deep-red flicker and flickering 2 c/deg geometric pattern stimuli produced by strobofilters. We investigated efficacy of eliciting PPR by use of Grass PS33-plus stroboscopic 18-Hz intermittent photic stimulation (IPS) and low-luminance 18-Hz visual stimuli.

METHODS

We studied 31 photosensitive patients. We gave stroboscopic IPS (eyes closed and eyes open); after deep-red flicker stimulation (eyes open), we gave flickering geometric-pattern stimuli by using dot, vertical grating, and horizontal grating patterns.

RESULTS

Stroboscopic IPS elicited PPR in 14 patients, whereas absence of PPR provocation was found in 17 patients. Low-luminance visual stimuli elicited PPR in 30 patients, whereas absence of PPR provocation was found in only one patient. These PPR provocation differences in both stimuli were statistically significant (p < 0.001).

CONCLUSIONS

The data suggest that low-luminance visual stimuli as described are useful for EEG diagnosis of ESGIS when seizures are thought to be due to photosensitivity.

Photosensitive and nonphotosensitive electronic screen game-induced seizures

PURPOSE

To disclose possible epileptologic differences between photosensitive and nonphotosensitive patients with seizures induced by electronic screen games (ESGs).

METHODS

In patients with ESG-induced seizures who showed photo- and pattern sensitivity, magnetoencephalography (MEG) and EEG were performed simultaneously during ESG play, and equivalent current dipoles (ECDs) of the MEG spikes were estimated. In patients without ESG-induced seizures, who were surgical candidates, the intracranial EEG was analyzed for changes in epileptiform spike frequency.

RESULTS

Fifteen of 29 patients were photo- or pattern sensitive, and they had a posterior predominance of ECDs of the MEG spikes. In contrast, nonphotosensitive patients had an anterior predominance of ECDs. Other seizure-precipitating factors in the nonphotosensitive patients included hand manipulation or spatial processing. In patients without a history of ESG-induced seizures who underwent intracranial EEG monitoring for surgical evaluation, ESG playing induced changes in spike frequency in the supplementary motor area, perisylvian region, and medial temporal lobe.

CONCLUSIONS

In photosensitive patients, interictal MEG spikes arise predominantly from the posterior region of the brain. In nonphotosensitive patients, epileptiform spikes tend to originate in the anterior part of the brain. Thus factors involving functions of the anterior part of the brain other than photo- or pattern sensitivity may play a role in the induction of seizures during ESG play. Furthermore, the changes in spike frequency in specific brain areas may correspond to their involvement in praxic activity and emotional changes during ESG play. A chance occurrence of seizures during ESG play also was observed.

The effect of video-game software in video-game epilepsy

PURPOSE

The individual role of video-game (VG) programs in VG activation is still unclear. Strict relations between VG seizures and photo- and pattern sensitivity suggest that programs per se may have a role in seizure activation.

METHODS

We tested a series of 12 commercially available VG programs in 30 subjects aged 7-28 years; test protocol comprised intermittent photic stimulation (IPS), pattern stimulation, and a game session with 12 programs, each played for 5 min, delivered from a 50-Hz screen.

RESULTS

Activation was observed in 17 subjects; marked differences were observed between different games: two programs activated 13 subjects; one program did not provoke activation. High variability between scenes makes it impossible to define mean brightness for the whole program. Activation correlated with "steady maximal brightness" (SMB) within a program; SMB is defined as the brightness in lux of the brightest scene steadily present in a program. SMB varied between 6 and 305 lux in tested programs. Difference in activation between different games was statistically significant (p < 0.001). Pattern sensitivity is strictly correlated with the probability of VG activation (p < 0.001).

CONCLUSIONS

Our study demonstrates a strong variation in activation between different game programs and a strict relation between VG activation and pattern sensitivity. Programs with SMB >100 lux should be regarded as potentially dangerous: programs with SMB <50 lux may be considered relatively safe.

Epilepsies and video games: results of a multicentric study

OBJECTIVES

The purpose of this study was to research whether or not video games may induce paroxysmal discharges (PD) in different groups of patients.

METHODS

One hundred and fifteen subjects from 5 different French laboratories were studied: 33 had seizures exclusively under visual stimuli, 42 had both photogenic seizures and spontaneous seizures occuring independently, and 40 had non-photogenic seizures. The same protocol which included one TV sequence, 3 sequences of video games selected on particular criteria (pattern, luminosity and nature of the scene), were presented at different distances from the TV screen at 50 and 100 Hz.

RESULTS

Among the factors provoking paroxysmal discharges (PD) some seem crucial: the frequency of the TV screen (the 100 Hz screen was significantly safer than 50 Hz), the distance from the screen (1 m safer than 50 cm), and, particularly for the 50 Hz screen, the specific pattern of the images and the act of playing.

CONCLUSIONS

Video games are ineffective for subjects known as having a non-photosensitive epilepsy, but may induce PD on subjects known as photosensitive even when intermittent light stimulation (ILS) is not effective. These results based on a different approach than in other publications confirm data which were suggested by the literature, and suggest that 100 Hz TV screens should be recommended to patients with TV-induced attacks.

Patient background of the Pokemon phenomenon: questionnaire studies in multiple pediatric clinics

Many children in Japan developed various neuropsychological problems, including seizures, while watching the program Pocket Monster, televised on 16 December 1997. To examine the basis for this incident, we have performed a survey of volunteering children and their parents who visited our pediatric clinics for other reasons from 8 January to 28 February 1998. Children and their parents filled out questionnaires. Among the total of 662 children surveyed, the great majority (603, 91.1%) was found to have watched the Pocket Monster program and 30 individuals (5.0% of viewers) complained of variable degrees of neuropsychological abnormalities. These included seizures (two cases), headache (nine cases), nausea (eight cases), blurred vision (four cases), vertigo (two cases), dysthymia (two cases) and vomiting (one case). Nearly half (14) of these children developed symptoms during or immediately after watching the program, while the remainder did so later. Representative cases are reported and other statistical aspects are discussed.