Reflex Seizures and Reflex Epilepsy

Neuroelectric Correlates of Human Sexuality: A Review and Meta-Analysis

Many reviews on sexual arousal in humans focus on different brain imaging methods and behavioral observations. Although neurotransmission in the brain is mainly performed through electrochemical signals, there are no systematic reviews of the electrophysiological correlates of sexual arousal. We performed a systematic search on this subject and reviewed 255 studies including various electrophysiological methods. Our results show how neuroelectric signals have been used to investigate genital somatotopy as well as basic genital physiology during sexual arousal and how cortical electric signals have been recorded during orgasm. Moreover, experiments on the interactions of cognition and sexual arousal in healthy subjects and in individuals with abnormal sexual preferences were analyzed as well as case studies on sexual disturbances associated with diseases of the nervous system. In addition, 25 studies focusing on brain potentials during the interaction of cognition and sexual arousal were eligible for meta-analysis. The results showed significant effect sizes for specific brain potentials during sexual stimulation (P3: Cohen's d = 1.82, N = 300, LPP: Cohen's d = 2.30, N = 510) with high heterogeneity between the combined studies. Taken together, our review shows how neuroelectric methods can consistently differentiate sexual arousal from other emotional states.

Transcriptome of the Krushinsky-Molodkina Audiogenic Rat Strain and Identification of Possible Audiogenic Epilepsy-Associated Genes

Audiogenic epilepsy (AE), inherent to several rodent strains is widely studied as a model of generalized convulsive epilepsy. The molecular mechanisms that determine the manifestation of AE are not well understood. In the present work, we compared transcriptomes from the corpora quadrigemina in the midbrain zone, which are crucial for AE development, to identify genes associated with the AE phenotype. Three rat strains without sound exposure were compared: Krushinsky-Molodkina (KM) strain (100% AE-prone); Wistar outbred rat strain (non-AE prone) and “0” strain (partially AE-prone), selected from F2 KM × Wistar hybrids for their lack of AE. The findings showed that the KM strain gene expression profile exhibited a number of characteristics that differed from those of the Wistar and “0” strain profiles. In particular, the KM rats showed increased expression of a number of genes involved in the positive regulation of the MAPK signaling cascade and genes involved in the positive regulation of apoptotic processes. Another characteristic of the KM strain which differed from that of the Wistar and “0” rats was a multi-fold increase in the expression level of the Ttr gene and a significant decrease in the expression of the Msh3 gene. Decreased expression of a number of oxidative phosphorylation-related genes and a few other genes was also identified in the KM strain. Our data confirm the complex multigenic nature of AE inheritance in rodents. A comparison with data obtained from other independently selected AE-prone rodent strains suggests some common causes for the formation of the audiogenic phenotype.

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.

Assessing various sensorimotor and cognitive functions in people with epilepsy is feasible with robotics

BACKGROUND

Epilepsy is a common neurological disorder characterized by recurrent seizures, along with comorbid cognitive and psychosocial impairment. Current gold standards of assessment can quantify cognitive and motor performance, but may not capture all subtleties of behavior. Here, we study the feasibility of assessing various upper limb sensorimotor and cognition functions in people with epilepsy using the Kinarm robotic assessment system. We quantify performance across multiple behavioral domains and additionally consider the possible effects of epilepsy subtype and medication.

METHODS

We recruited individuals with a variety of epilepsy subtypes. Participants performed 8 behavioral tasks that tested motor, cognitive, and sensory domains. We collected data on the same tasks from a group of control participants that had no known neurological impairments. We quantified performance using Task Scores, which provide a composite measure of overall performance on a given task and are adjusted for age, sex, and handedness.

RESULTS

We collected data from 46 individuals with epilepsy and 92 control participants. The assessment was well-tolerated, with no adverse events recorded. Cognitive tasks testing spatial working memory, executive function, and motor response inhibition were the most frequently impaired in the epilepsy cohort, with 33/46 (72%) being outside the normal range on at least one of these tasks. Additionally, 29/46 (63%) were impaired on at least one task testing primarily motor skill, and 14/46 (30%) were impaired on a proprioceptive sensory task. People with either focal epilepsy or generalized epilepsy performed significantly worse on both motor and cognitive tasks than control participants after correcting for multiple comparisons. There were no statistical differences between generalized and focal epilepsy groups on Task Scores. Finally, individuals taking topiramate trended toward having worse performance on a spatial working memory task than other individuals with epilepsy who were not taking topiramate.

CONCLUSIONS

Kinarm robotic assessment is feasible in individuals with epilepsy and is well-tolerated. Our robotic paradigm can detect impairments in various sensorimotor and cognitive functions across the population with epilepsy. Future studies will explore the role of epilepsy subtype and medications.

Clinical and electrophysiological findings in patients with phenylketonuria and epilepsy: Reflex features

OBJECTIVE

Phenylketonuria (PKU) is the most common form of amino acid metabolism disorders with autosomal recessive inheritance. The brain damage can be prevented by early diagnosis and a phenylalanine-restricted diet. Untreated or late-treated patients may show mental retardation and other cognitive dysfunctions, as well as motor disability and/or epilepsy.

METHODS

Three patients with PKU and epilepsy were recognized to have reflex epileptic features, and there were ten consecutive adult patients with PKU and epilepsy who were evaluated retrospectively. Medical history, ages at diagnosis and therapy onset, age at seizure onset, seizure types and reflex features, neurological findings, cranial imaging, electroencephalography (EEG) findings, and final clinical condition were evaluated. Reflex epilepsy features were examined in detail.

RESULTS

The cases (6 females, 4 males) were diagnosed at ages between 3.5months and 12years. All patients had various degrees of mental-motor retardation and focal or generalized seizures with age at seizure onset varied between neonatal period and 15years. Three patients had febrile seizure, 3 patients had myoclonia, and 3 patients had status epilepticus. All patients had abnormal EEG findings except one. There was a slowing of background activity, and generalized discharges were observed in 7 patients; 3 of them had asymmetrical discharges. One patient had right hippocampal sclerosis (HS), and another patient had hypointensities in the basal ganglia and corpus callosum. Reflex features were clinically observed in 3 of the patients; however, EEG results did not show any related findings. One patient had reflex seizures triggered by photic stimuli, hot water, and startling; one by photic stimuli; and the other one by startling.

CONCLUSION

Reports on the clinical and electrophysiological features of adult patients with PKU were scant. We emphasized that reflex clinical features may be observed in this metabolic disease, and focal epileptiform abnormalities and asymmetry may be present in electrophysiological evaluation besides the rare association with HS.

Emotional stimuli-provoked seizures potentially misdiagnosed as psychogenic non-epileptic attacks: A case of temporal lobe epilepsy with amygdala enlargement

The association between emotional stimuli and temporal lobe epilepsy (TLE) is largely unknown. Here, we report the case of a depressed, 50-year-old female complaining of episodes of a “spaced out” experience precipitated by emotional stimuli. Psychogenic non-epileptic attacks were suspected. However, video-EEG coupled with emotional stimuli-provoked procedures and MRI findings of amygdala enlargement, led to the diagnosis of left TLE. Accurate diagnosis and explanation improved her subjective depression and seizure frequency. This case demonstrated that emotional stimuli can provoke seizures in TLE and suggested the involvement of the enlarged amygdala and the modulation of emotion-related neural circuits.

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Emotional stimuli provoked seizures in TLE with amygdala enlargement.

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Amygdala enlargement may be associated with the mechanism that elicits seizures.

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Optimizing anti-seizure drugs and emotional stimuli management were crucial.

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A correct diagnosis may resolve the distress of patients with PNEA and/or TLE.

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Thorough investigation is needed before the diagnosis of PNEA is confirmed.

Worldwide policies on epilepsy and blood donation: a survey among blood services

BACKGROUND AND OBJECTIVES

Epilepsy is a common neurological disorder characterized by the appearance of seizures. Often, epilepsy patients are temporarily or permanently excluded from blood donation. To gain a better understanding of the policies that are currently applied, we performed a survey among blood services.

METHODS

A cross-sectional, Web-based questionnaire using the online Questback tool was developed and distributed to 46 representatives of blood services worldwide. The questionnaire was composed of nine questions.

RESULTS

A total of 27 respondents, representing blood services in 26 countries on five continents, participated in the survey. Current policies range from permanent acceptance over temporary exclusion to permanent exclusion. Rationales for these different policies are diverse. The majority of blood services (59·3%) apply temporary exclusion as their policy, though no consensus exists on the length of time that epilepsy patients have to be medication-free or seizure-free. None of the respondents could provide data about adverse events in epilepsy patients during the blood donation process.

CONCLUSIONS

The results of this survey indicate a large discrepancy in policies applied worldwide. A lack of scientific evidence could be one of the underlying reasons. Therefore, it is of paramount importance to further research the potential risks for donors and recipients regarding blood donation by people with epilepsy. This can then serve as a base for evidence-based policymaking and lead to safer and more effective blood transfusion programmes.

What is orgasm? A model of sexual trance and climax via rhythmic entrainment

Orgasm is one of the most intense pleasures attainable to an organism, yet its underlying mechanisms remain poorly understood. On the basis of existing literatures, this article introduces a novel mechanistic model of sexual stimulation and orgasm. In doing so, it characterizes the neurophenomenology of sexual trance and climax, describes parallels in dynamics between orgasms and seizures, speculates on possible evolutionary origins of sex differences in orgasmic responding, and proposes avenues for future experimentation. Here, a model is introduced wherein sexual stimulation induces entrainment of coupling mechanical and neuronal oscillatory systems, thus creating synchronized functional networks within which multiple positive feedback processes intersect synergistically to contribute to sexual experience. These processes generate states of deepening sensory absorption and trance, potentially culminating in climax if critical thresholds are surpassed. The centrality of rhythmic stimulation (and its modulation by salience) for surpassing these thresholds suggests ways in which differential orgasmic responding between individuals-or with different partners-may serve as a mechanism for ensuring adaptive mate choice. Because the production of rhythmic stimulation combines honest indicators of fitness with cues relating to potential for investment, differential orgasmic response may serve to influence the probability of continued sexual encounters with specific mates.

Micturition-induced seizures: a rare form of reflex epilepsy

BACKGROUND

Reflex seizures are referred to as epileptic seizures that are consistently precipitated by a specific sensory stimulus. Reflex seizures induced by micturition are very rare, and few cases have been described.

METHODS

This study reports a case of an 11-year-old girl with seizures provoked by micturition with reference made to previously reported cases in the literature. Seizures were characterized by head and eye deviation to the right, flexed dystonic posturing of the left upper limb, extension of the right upper limb, and eventual generalized tonic-clonic seizure. Ictal electroencephalogram revealed clear electrographic evolution from the midcentral region with secondary generalization. Magnetic resonance imaging of the head was normal. Seizures were treated with a combination of lacosamide and clobazam.

CONCLUSIONS

A midcentral ictal focus is in keeping with previous reports of this area as a potential epileptogenic center for micturition-induced seizures.

Clinical, neurological, and electrophysiological features of nodding syndrome in Kitgum, Uganda: an observational case series

BACKGROUND

Nodding syndrome is an unexplained illness characterised by head-bobbing spells. The clinical and epidemiological features are incompletely described, and the explanation for the nodding and the underlying cause of nodding syndrome are unknown. We aimed to describe the clinical and neurological diagnostic features of this illness.

METHODS

In December, 2009, we did a multifaceted investigation to assess epidemiological and clinical illness features in 13 parishes in Kitgum District, Uganda. We defined a case as a previously healthy child aged 5-15 years with reported nodding and at least one other neurological deficit. Children from a systematic sample of a case-control investigation were enrolled in a clinical case series which included history, physical assessment, and neurological examinations; a subset had electroencephalography (EEG), electromyography, brain MRI, CSF analysis, or a combination of these analyses. We reassessed the available children 8 months later.

FINDINGS

We enrolled 23 children (median age 12 years, range 7-15 years) in the case-series investigation, all of whom reported at least daily head nodding. 14 children had reported seizures. Seven (30%) children had gross cognitive impairment, and children with nodding did worse on cognitive tasks than did age-matched controls, with significantly lower scores on tests of short-term recall and attention, semantic fluency and fund of knowledge, and motor praxis. We obtained CSF samples from 16 children, all of which had normal glucose and protein concentrations. EEG of 12 children with nodding syndrome showed disorganised, slow background (n=10), and interictal generalised 2·5-3·0 Hz spike and slow waves (n=10). Two children had nodding episodes during EEG, which showed generalised electrodecrement and paraspinal electromyography dropout consistent with atonic seizures. MRI in four of five children showed generalised cerebral and cerebellar atrophy. Reassessment of 12 children found that six worsened in their clinical condition between the first evaluation and the follow-up evaluation interval, as indicated by more frequent head nodding or seizure episodes, and none had cessation or decrease in frequency of these episodes.

INTERPRETATION

Nodding syndrome is an epidemic epilepsy associated with encephalopathy, with head nodding caused by atonic seizures. The natural history, cause, and management of the disorder remain to be determined.

FUNDING

Division of Global Disease Detection and Emergency Response, US Centers for Disease Control and Prevention.

Seizure-free after surgery in a patient with non-lesional startle epilepsy: a case report

We present the case of a patient with startle epilepsy provoked by auditory, somatosensory and visual stimuli during video-electrocorticography (ECoG) recording. Ictal ECoG of all types of seizures triggered by the three kinds of stimuli showed that seizure onset originated from the left supplementary sensorimotor area (SSMA). The patient has been seizure-free after the cortex around the left SSMA only had been resected. Therefore, we speculate that left SSMA is the epileptogenic zone of startle epilepsy in this patient and perhaps the primary cortex to modulate the startle reflex in healthy persons.

Brain and Psyche in Early Christian Asceticism

This study is an 11-part investigation of the psychology and neuropsychology of early Christian asceticism as represented by Evagrius Ponticus (AD 345–399), the tradition's first ascetical theologian and possibly its most influential. Evagrius's biography is reviewed in the first section. The living circumstances and perceptual consequences of desert asceticism are considered in the second. Penitence, dispassion, and the mysticism of “pure prayer” are discussed in the third. Austerities are addressed in the fourth section, particularly fasting, prostrations, and prolonged standing. Ascetical perspectives on sleep, dreams, and the hypnogogic state are analyzed in the fifth. The depressive syndrome of acedia is discussed in the sixth. Evagrius's reports of auditory, olfactory, and visual hallucinations are analyzed in the seventh. Multiple complementary interpretations of demonic phenomena are developed in the eighth section. Evagrius's psychotherapy for anger is reviewed in the ninth. Interpersonal relations among ascetics are considered in the tenth section. The study concludes with a summary.

The classification of seizures and epilepsy syndromes

This chapter focuses on the classification of seizures and epilepsy syndromes based on the International League Against Epilepsy's classification systems from 1981 and 1989, respectively, which are still used today in clinical practice and have formed the basis for a worldwide standardized approach to diagnosing, treating, and studying seizure disorders. This classification system is based on clinical seizure semiology and EEG correlation and makes a distinction between focal and generalized seizures. The clinical semiology and localization of simple partial, complex partial, and generalized seizures are discussed. Some common partial and generalized epilepsy syndromes are also highlighted.

Vagus nerve stimulation might have a unique effect in reflex eating seizures

We studied the effects of vagus nerve stimulation (VNS) on eating seizures, which theoretically would be triggered by neural activity and signaling from organs innervated by the vagus nerve. Three adult patients with daily nonreflex and reflex eating seizures were studied; one patient also had hot-water seizures. One patient had bilateral polymicrogyria and two had normal magnetic resonance imaging (MRI) findings. All patients were submitted to VNS implantation and had at least 2 years of postimplantation follow-up. Final stimulation parameters were 2.0-2.5 mA, 500 micros, and 30 Hz. Eating seizures decreased 70-95% and nonreflex seizures decreased 0-40% after VNS. There was no improvement in hot-water seizures. VNS seems to be an especially useful treatment modality in patients with reflex eating seizures not amenable to resective surgery.

Epileptic seizures and hippocampal damage after cuprizone-induced demyelination in C57BL/6 mice

Epileptic seizures are known to occur in different animal models of demyelination and have also been described in demyelinating diseases of the central nervous system (CNS) such as multiple sclerosis. How myelin deficiency might cause seizures is unknown, but may involve axonal pathology and resultant alterations in neuronal excitability. The cause of seizures occurring in rodent demyelination models is unknown. In the present study, we used EEG/video monitoring to record seizures occurring during chronic demyelination of C57BL/6 mice fed for 12 weeks with 0.2% cuprizone. Furthermore, in the search for a morphological correlate of the seizures, the hippocampal formation was examined histologically. Epileptiform spikes resembling interictal spikes known from chronic epilepsy were recorded in all cuprizone-treated mice, but not in controls. Most cuprizone-treated animals exhibited generalized tonic-clonic seizures upon stress-inducing stimuli. In addition to the known demyelination of the corpus callosum, massive demyelination was found in the hippocampal formation. This was associated with neuronal alterations, including a loss of neurons in the hilus of the dentate gyrus. In view of the role of the dentate gyrus in epileptogenesis, demyelination leading to axonal pathology and thus neuronal damage as observed in the hilus may be causally involved in the paroxysmal alterations observed after prolonged treatment with cuprizone. The present data suggest a potential role of the hippocampal formation for seizures occurring as a consequence of neuronal damage secondary to CNS demyelination.