Object and action naming in Russian individuals with epilepsy
Naming difficulties are one of the most common language deficits in aphasia. The aim of the present study was to develop a psycholinguistic test for object and action naming in aphasia. Data collected during standardization of the subtest for naming objects (116 stimuli) and actions (197 stimuli) demonstrated, that the proposed test is sensitive to anomia in different types and severity of aphasia. Criterion and concurrent validity of the subtest were established as well. Based on collected data more compact subtests for use in the clinic with items of varying difficulty taking into account relevant psycholinguistic properties will be constructed.
Special issue of Epilepsia dedicated to the 31stInternational Epilepsy Congress Istanbul, Turkey 5th–9th September, 2015
The retrieval of low frequency words is usually slower than that of high frequency words. Neuroimaging research on the role of word frequency in linguistic tasks suggests candidate brain areas for the neural substrates of this effect. The only previous fMRI study of word frequency in Russian (Malutina et al., 2012) used an action naming task and obtained data that were highly inconsistent with results for other languages, findings which were mainly obtained using noun-retrieval tasks. In order to verify whether the reasons for such inconsistency were methodological or cross-linguistic, we examined the fMRI correlates of word frequency in Russian using a covert object naming task. We found that the retrieval of low frequency and high frequency nouns activated the same general pattern of brain areas typical for object naming tasks in many languages. Several brain regions were more activated in the low frequency but not the high frequency condition, including the areas and structures usually associated with linguistic processing (the inferior frontal gyrus bilaterally, the left thalamus, the left insula), visual perception (the fusiform gyrus, the inferior occipital gyrus, the middle occipital gyrus bilaterally) and cognitive and motor control (the supplementary motor area and the right cingulate gyrus). The right cingulate gyrus was the only area that responded only to the low frequency stimuli but not the high frequency items, when compared to the baseline. At the same time, we found no brain areas that responded more to high versus low word frequency. These results are generally consistent with previous fMRI studies in English, German and Chinese and therefore suggest that the inconsistency between the previous research in Russian and other languages was due to the possible interaction of the part of speech (verb or noun) and word frequency in brain mechanisms for word retrieval, rather than cross-linguistic differences.
Abstracts of the 12th European Congress on Epileptology
Pharmacoresistant epilepsy is a chronic neurological condition in which a basal brain hyperexcitability results in paroxysmal hypersynchronous neuronal discharges. Human temporal lobe epilepsy has been associated with dysfunction or loss of the potassium-chloride cotransporter KCC2 in a subset of pyramidal cells in the subiculum, a key structure generating epileptic activities. KCC2 regulates intraneuronal chloride and extracellular potassium levels by extruding both ions. Absence of effective KCC2 may alter the dynamics of chloride and potassium levels during repeated activation of GABAergic synapses due to interneuron activity. In turn, such GABAergic stress may itself affect Cl− regulation. Such changes in ionic homeostasis may switch GABAergic signaling from inhibitory to excitatory in affected pyramidal cells and also increase neuronal excitability. Possibly these changes contribute to periodic bursting in pyramidal cells, an essential component in the onset of ictal epileptic events. We tested this hypothesis with a computational model of a subicular network with realistic connectivity. The pyramidal cell model explicitly incorporated the cotransporter KCC2 and its effects on the internal/external chloride and potassium levels. Our network model suggested the loss of KCC2 in a critical number of pyramidal cells increased external potassium and intracellular chloride concentrations leading to seizure-like field potential oscillations. These oscillations included transient discharges leading to ictal-like field events with frequency spectra as in vitro. Restoration of KCC2 function suppressed seizure activity and thus may present a useful therapeutic option. These simulations therefore suggest that reduced KCC2 cotransporter activity alone may underlie the generation of ictal discharges.
Research on comparative efficаcy and tolerability of monotherapy with Depakine chronosphere, drugs of Carbamazepine group with ex- tended release and oxcarbazepine in symptomatic and cryptogenic focal epilepsy has been conducted at Svt. Luka’s Institute of Child Neurol- ogy and Epilepsy (ICNE) (Moscow). This retrospective study covers a random sample of patients treated in ICNE in the period from Decem- ber 1, 2013 to September 1, 2014. The study included 131 patients aged 1 to 18 years with symptomatic and cryptogenic focal epilepsy receiving treatment with one of the study drugs in monotherapy: group 1 - monotherapy with Depakine chronosphere (n = 56); group 2 - monotherapy with drugs of carbamazepine group with extended release (n = 55); group 3 - monotherapy with oxcarbazepine (trileptal) (n = 20).The obtained results allow us to conclude that the effectiveness of Depakin chronosphere, carbamazepine with extended release and oxcar- bazepine in monotherapy of symptomatic and cryptogenic focal epilepsy was comparable (statistically significant differences in efficacy were not found). However, carbamazepine was awarded the highest frequency of seizures aggravation.Drugs showed approximately same tolerability (statistically significant differences in tolerability were not found). However, withdrawal of the drug due to side effects was the rarest in Depakine (3.5 %), and withdrawal due to intolerance was higher in carbamazepine and oxcarbazepine (5 and 10 % respectively).Depakinum and oxcarbazepine had the best results in the blocking of pathological activity on the electroencephalogram, whereas carbam- azepine was clearly inferior to them. In this regard, complete clinical-electroencephalographic remission (lasting 12 months or more) was achieved under treatment of Depakine chromosphere in 21.5 % of cases, oxcarbazepine - 20 %, and carbamazepine - only 11 %. Holding on therapy for 12 months was similar in all study drugs.Considering that the objective of epilepsy treatment is to achieve complete control over seizures, or at least substantially reduce and weaken them in the absence of significant side effects that disturb the patient’s quality of life, it can be concluded that the best treatment results were obtained in group of depakine chronosphere therapy.