Clinical Neuroscience

[Event-related potentials and clinical symptoms in schizophrenia]

DOMJÁN Nóra1, CSIFCSÁK Gábor2, JANKA Zoltán1

JANUARY 30, 2016

Clinical Neuroscience - 2016;69(01-02)

DOI: https://doi.org/10.18071/isz.69.0013

[The investigation of schizophrenia’s aetiology and pathomechanism is of high importance in neurosciences. In the recent decades, analyzing event-related potentials have proven to be useful to reveal the neuropsychological dysfunctions in schizophrenia. Even the very early stages of auditory stimulus processing are impaired in this disorder; this might contribute to the experience of auditory hallucinations. The present review summarizes the recent literature on the relationship between auditory hallucinations and event-related potentials. Due to the dysfunction of early auditory sensory processing, patients with schizophrenia are not able to locate the source of stimuli and to allocate their attention appropriately. These deficits might lead to auditory hallucinations and problems with daily functioning. Studies involving high risk groups may provide tools for screening and early interventions; thus improving the prognosis of schizophrenia. ]

AFFILIATIONS

  1. Szegedi Tudományegyetem, Általános Orvostudományi Kar, Pszichiátriai Klinika, Szeged
  2. Szegedi Tudományegyetem, Bölcsészettudományi Kar, Pszichológiai Intézet, Szeged

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[Financing of medicines for treatment of rare diseases of the nervous system. orphan drugs in rare neurological diseases]

SZEGEDI Márta, KOSZTOLÁNYI György, BONCZ Imre, MOLNÁR Mária Judit

[Objectives – Nervous system involvement is expected up to 60-70% in case of rare diseases. This article aims to present the financial methods and expenditures of rare neurological diseases’ orphan medicinal products being financed in the frame of Hungarian social insurance system in 2012. Methods – The subsidized orphan medicines were selected on the Orphanet portal 2012 while orphans financed by compessionate use were provided by the Hungarian National Insurance Fund Administration (OEP) database. Three products exist without orphan designation, however those are intended for the treatment of rare neurological ailments. The medicines were categorized by financial methods and determined by costs. Results – Numerically, out of 36 pieces of subsidized orphan or orphan criteria fulfilled medicines 17 were authorized for the treatments of rare neurological diseases in the year of 2012. Most of the drugs (14 pieces) were to be financed in the frame of compassionate use by the reimbursement system. The cost amount of social insurance for 387 rare neurological disease patients reached more than 4.5 billion HUF (1.4% of the total pharmaceutical budget in outpatient care). Conclusions – In Hungary half of the subsidized orphans are intended for the treatments of rare neurological ailments. 30% of the total amount of social insurance for rare diseases’ medicinal treatments were used to subsidizing rare neurological disease patients in 2012. Most of the orphan medicines were to be financed in the frame of compassionate use by the reimbursement system for outpatient care. Consequently, a great deal of crucial problems occurred in relation with the unconventional subsidizing method. At the end of 2012 new financial methods have been elaborated and introduced in a pilot phase from 1 January 2013. In spite of the high cost commitment, nearly the entire diagnosed rare disease subpopulation have been provided with subsidized treatments in Hungary. In order to facilitate the acces to orphan medicines, collaboration shall be achieved by financing authority and professionals for identificating the descently sustainable, affordable and viable financial method. ]

Clinical Neuroscience

Unanswered questions in the transcranial magnetic stimulation treatment of patients with depression

MORVAI Szabolcs, NAGY Attila, KOVÁCS Attila, MÓRÉ Csaba, BERECZ Roland, FRECSKA Ede

According to the WHO fact sheet depression is a common mental disorder affecting 350 million people of all ages worldwide. Transcranial Magnetic Stimulation (TMS) is a technique which allows the investigator to stimulate and study cortical functions in healthy subjects and patients suffering from various mental and neurological disorders. In the early 1990s, studies revealed that it is possible to evoke long term mood changes in healthy volunteers by rapid rate repetitive, TMS (rTMS) over the frontal cortex. Subsequent studies involving depressed patients found frontal cortical rTMS administered daily to be clinically effective. In the past two decades, numerous trials examined the therapeutic potential of rTMS application in the treatment of mood disorders with constantly evolving treatment protocols. The aim of this paper is to review the literature of the past two decades, focusing on trials addressing the efficacy and safety of rTMS in depressed patients. Our primary goal is to evaluate the results in order to direct future studies which may help investigators in the development of treatment protocols suitable in hospital settings. The time is not far when TMS devices will be used routinely by practitioners primarily for therapeutic purpose rather than clinical research. To our knowledge, a widely accepted “gold standard" that would offer the highest efficacy, with the best tolerability has not been established yet. In order to approach this goal, the most important factors to be addressed by further studies are: localization, frequency, intensity, concurrent medication, maintenance treatments, number of pulses, trains, unilateral, or bilateral mode of application.

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Objectives – A retrospective study has been done at the Bethesda Children’s Hospital Epilepsy Center with those patients whose EEG records fulfilled in one or more records the criteria of electrical status epilepticus in slow wave sleep (ESES) pattern, occupying at least 75% of NREM sleep with bilateral discharges, and had detailed disease history and long term follow-up data, between 2000 and 2012. Patients and methods – Thirty-three patients (mean 11.1±4.2 years of age) were studied by 171 sleep EEG records. Sleep was recorded after sleep deprivation or during spontaneous sleep at least for one hour length of NREM. From the 492 EEGs, 171 sleep records were performed (average five/patient). Average follow-up time was 7.5 years. Eighty-two ESES records have been analyzed in 15 non-lesional and 18 lesional (11 with dysgenetic and seven with perinatal - asphyxic or vascular origin) patients. Variability of seizure types, seizure frequency and frequency of status epilepticus was higher in the lesional group. Impairment of the cognitive functions was moderate and partial in the non-lesional, while severely damaged in the lesional group. Results – EEG records of 29 patients showed unihemispherial spike fields with a perpendicular axis (in anterior, medial and posterior variants) to the Sylvian fissure, regardless their lesional or non-lesional origin. Only three (1one non-lesional and two lesional) patients had bilateral synchronous spike-wave discharges with bilateral symmetric frontocentral spike fields. The individual discharges of the sleep EEG pattern were very similar to the awake interictal records except their extension in time and field, their increased number, amplitude, and continuity of them and furthermore in the increased trans-hemispheral propagation and their synchronity. Conclusions – Assumed circuits involved in the pathomechanism of discharges during NREM sleep in ESES are discussed based on our findings.

Clinical Neuroscience

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Clinical Neuroscience

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