Investigating neuromagnetic brain responses against chromatic flickering stimuli by wavelet entropies

BACKGROUND: Photosensitive epilepsy is a type of reflexive epilepsy triggered by various visual stimuli including colourful ones. Despite the ubiquitous presence of colorful displays, brain responses against different colour combinations are not properly studied. METHODOLOGY/PRINCIPAL FINDINGS: Here, we studied the photosensitivity of the human brain against three types of chromatic flickering stimuli by recording neuromagnetic brain responses (magnetoencephalogram, MEG) from nine adult controls, an unmedicated patient, a medicated patient, and two controls age-matched with patients. Dynamical complexities of MEG signals were investigated by a family of wavelet entropies. Wavelet entropy is a newly proposed measure to characterize large scale brain responses, which quantifies the degree of order/disorder associated with a multi-frequency signal response. In particular, we found that as compared to the unmedicated patient, controls showed significantly larger wavelet entropy values. We also found that Renyi entropy is the most powerful feature for the participant classification. Finally, we also demonstrated the effect of combinational chromatic sensitivity on the underlying order/disorder in MEG signals. CONCLUSIONS/SIGNIFICANCE: Our results suggest that when perturbed by potentially epileptic-triggering stimulus, healthy human brain manages to maintain a non-deterministic, possibly nonlinear state, with high degree of disorder, but an epileptic brain represents a highly ordered state which making it prone to hyper-excitation. Further, certain colour combination was found to be more threatening than other combinations

Epilepsy Caused by an Abnormal Alternative Splicing with Dosage Effect of the SV2A Gene in a Chicken Model

Photosensitive reflex epilepsy is caused by the combination of an individual's enhanced sensitivity with relevant light stimuli, such as stroboscopic lights or video games. This is the most common reflex epilepsy in humans; it is characterized by the photoparoxysmal response, which is an abnormal electroencephalographic reaction, and seizures triggered by intermittent light stimulation. Here, by using genetic mapping, sequencing and functional analyses, we report that a mutation in the acceptor site of the second intron of SV2A (the gene encoding synaptic vesicle glycoprotein 2A) is causing photosensitive reflex epilepsy in a unique vertebrate model, the Fepi chicken strain, a spontaneous model where the neurological disorder is inherited as an autosomal recessive mutation. This mutation causes an aberrant splicing event and significantly reduces the level of SV2A mRNA in homozygous carriers. Levetiracetam, a second generation antiepileptic drug, is known to bind SV2A, and SV2A knock-out mice develop seizures soon after birth and usually die within three weeks. The Fepi chicken survives to adulthood and responds to levetiracetam, suggesting that the low-level expression of SV2A in these animals is sufficient to allow survival, but does not protect against seizures. Thus, the Fepi chicken model shows that the role of the SV2A pathway in the brain is conserved between birds and mammals, in spite of a large phylogenetic distance. The Fepi model appears particularly useful for further studies of physiopathology of reflex epilepsy, in comparison with induced models of epilepsy in rodents. Consequently, SV2A is a very attractive candidate gene for analysis in the context of both mono- and polygenic generalized epilepsies in humans

Revisiting the Twentieth Century Through the Lens of Generation X and Digital Games: A Scoping Review

Video games have been around since the 1960s and have impacted upon society in a myriad of different ways. The purpose of this scoping review is to identify existing literature within the domain of video games which recruited participants from the Generation X (1965–1980) cohort. Six databases were searched (ACM, CINHAL Google Scholar, PubMed, Scopus, and Web of Science) focusing on published journal papers between 1970 and 2000. Search results identified 3186 articles guided by the PRISMA Extension for Scoping Reviews (PRISMA-ScR); 4 papers were irretrievable, 138 duplicated papers were removed, leaving 3048 were assessed for eligibility and 3026 were excluded. Articles (n = 22) were included into this review, with four papers primarily published in 1997 and in 1999. Thematic analysis identified five primary themes: purpose and objectives, respective authors’ reporting, technology, ethics and environment) and seven secondary themes: populations, type of participants (e.g. children, students), ethical approval, study design, reimbursement, language, type of assessments. This scoping review is distinctive because it primarily focuses on Generation X, who have experienced and grown-up with videogames, and contributes to several disciplines including: game studies, gerontology and health, and has wider implications from a societal, design and development perspective of video games

Migraine in the borderland of epilepsy. ‘‘Migralepsy’’ an overlapping syndrome of children and adults?

Gowers gave migraine a place in the borderland of epilepsy, justified by many relations and the fact that distinction of these two diseases is difficult. Gowers based his ideas on clinical histories from his patients, and he concluded that in extremely rare instances one may develop while the other goes on. In modern times, patient testimonies of the problem of differentiating migraine from epilepsy are given in health-chat Websites. It shows clearly that distinction between the two conditions is still problematic and that migralepsy is either nonexisting or extremely rare as Gowers noticed

GWAS meta-analysis of over 29,000 people with epilepsy identifies 26 risk loci and subtype-specific genetic architecture

Epilepsy is a highly heritable disorder affecting over 50 million people worldwide, of which about one-third are resistant to current treatments. Here we report a multi-ancestry genome-wide association study including 29,944 cases, stratified into three broad categories and seven subtypes of epilepsy, and 52,538 controls. We identify 26 genome-wide significant loci, 19 of which are specific to genetic generalized epilepsy (GGE). We implicate 29 likely causal genes underlying these 26 loci. SNP-based heritability analyses show that common variants explain between 39.6% and 90% of genetic risk for GGE and its subtypes. Subtype analysis revealed markedly different genetic architectures between focal and generalized epilepsies. Gene-set analyses of GGE signals implicate synaptic processes in both excitatory and inhibitory neurons in the brain. Prioritized candidate genes overlap with monogenic epilepsy genes and with targets of current antiseizure medications. Finally, we leverage our results to identify alternate drugs with predicted efficacy if repurposed for epilepsy treatment

Comorbidity of migraine in children presenting with epilepsy to a tertiary care center

Not available

\u201cIctal epileptic headache\u201d and the revised International Headache Classification (ICHD-3) published in Cephalalgia 2018, vol. 38(1) 1\u2013211: Not just a matter of definition!

No abstract available