Long-term outcome after cognitive and behavioral regression in nonlesional epilepsy with continuous spike-waves during slow-wave sleep.

Purpose: To present the long-term follow-up of 10 adolescents and young adults with documented cognitive and behavioral regression as children due to nonlesional focal, mainly frontal, epilepsy with continuous spike-waves during slow wave sleep (CSWS).

Methods: Past medical and electroencephalography (EEG) data were reviewed and neuropsychological tests exploring main cognitive functions were administered.

Key Findings: After a mean duration of follow-up of 15.

Visemic processing in audiovisual discrimination of natural speech: a simultaneous fMRI-EEG study.

In a noisy environment, visual perception of articulatory movements improves natural speech intelligibility. Parallel to phonemic processing based on auditory signal, visemic processing constitutes a counterpart based on "visemes", the distinctive visual units of speech. Aiming at investigating the neural substrates of visemic processing in a disturbed environment, we carried out a simultaneous fMRI-EEG experiment based on discriminating syllabic minimal pairs involving three phonological contrasts, each bearing on a single phonetic feature characterised by different degrees of visual distinctiveness.

What Physiological Changes and Cerebral Traces Tell Us about Adhesion to Fiction During Theater-Watching?

Live theater is typically designed to alter the state of mind of the audience. Indeed, the perceptual inputs issuing from a live theatrical performance are intended to represent something else, and the actions, emphasized by the writing and staging, are the key prompting the adhesion of viewers to fiction, i.e.

Is there an alternative cerebral network associated with enhanced phonological processing in deaf speech-users? An exceptional case.

Most people born deaf and exposed to oral language show scant evidence of sensitivity to the phonology of speech when processing written language. In this respect they differ from hearing people. However, occasionally, a prelingually deaf person can achieve good processing of written language in terms of phonological sensitivity and awareness, and in this respect appears exceptional.

The assessment of auditory function in CSWS: lessons from long-term outcome.

In Landau-Kleffner syndrome (LKS), the prominent and often first symptom is auditory verbal agnosia, which may affect nonverbal sounds. It was early suggested that the subsequent decline of speech expression might result from defective auditory analysis of the patient's own speech. Indeed, despite normal hearing levels, the children behave as if they were deaf, and very rapidly speech expression deteriorates and leads to the receptive aphasia typical of LKS.

Reading disabilities in SLI and dyslexia result from distinct phonological impairments.

Children with specific language impairment (SLI) who show impaired phonological processing are at risk of developing reading disabilities, which raises the question of phonological impairment commonality between developmental dyslexia (DD) and SLI. In order to distinguish the failing phonological processes in SLI and DD, we investigated the different steps involved in speech processing going from perceptual discrimination through various aspects of phonological memory. Our results show that whereas the memory for sequence is likewise impaired in either disorder, children with SLI have to face additional impairment in phonological discrimination and short-term memory, which may account for even poorer phonological awareness than dyslexics'.

Phonological processing in relation to reading: an fMRI study in deaf readers.

Without special education, early deprivation of auditory speech input, hinders the development of phonological representations and may alter the neural mechanisms of reading. By using fMRI during lexical and rhyming decision tasks, we compared in hearing and pre-lingually deaf subjects the neural activity in functional regions of interest (ROIs) engaged in reading. The results show in deaf readers significantly higher activation in the ROIs relevant to the grapho-phonological route, but also in the posterior medial frontal cortex (pMFC) and the right inferior frontal gyrus (IFG).

Neuropsychological findings in Rolandic epilepsy and Landau-Kleffner syndrome.

In an attempt to correlate neuropsychological deficits and various neurophysiological aspects of focal epileptic activity in benign childhood epilepsy, we have reviewed the findings of a longitudinal group study of benign childhood epilepsy with centrotemporal spikes (BCECTS) and several case studies of continuous spike-waves during slow sleep syndrome (CSWS). We first distinguish the temporary neuropsychological impairments often observed in the natural history of BCECTS from the more long-lasting and more specific neuropsychological deficits associated with CSWS, of which the Landau-Kleffner syndrome (LKS) is the most studied clinical form. A series of metabolic findings from (18)FDG-PET studies in BCECTS and CSWS children have shown that specific cognitive impairment is related to increased glucose uptake in cortical areas restricted to the associative cortex coincident with the focus of spike-wave discharges.

Neural responses associated with positive and negative emotion processing in patients with left versus right temporal lobe epilepsy.

Studies on emotion processing in patients with temporal lobe epilepsy have dealt mainly with the processing of negative emotions. To further understand the neural basis of emotional disorders in temporal lobe epilepsy, we studied patterns of brain activation induced by implicit processing of negative and positive emotions perceived through facial expressions and emotionally salient stimuli in candidates for surgical treatment of intractable epilepsy. Using functional MRI, we compared, in patients with mesial temporal lobe epilepsy and healthy subjects, the patterns of brain activation elicited by the implicit processing of fearful, sad, and happy faces and pleasant and unpleasant scenes.

Landau-Kleffner syndrome is not an eponymic badge of ignorance.

In a 1992 editorial article, Landau expressed the hope of collective agreement in the medical community about Landau-Kleffner syndrome (LKS) in terms of diagnosis criteria, etiology, pathophysiology and rational therapy. Since then, neurophysiological and neuroimaging studies have led to the view that LKS is an acquired aphasia, secondary to an epileptic disturbance affecting a cortical area involved in verbal processing. This fits with the hypothesis of a "functional ablation" caused by epileptic activity.

SRPX2 mutations in disorders of language cortex and cognition.

The rolandic and sylvian fissures divide the human cerebral hemispheres and the adjacent areas participate in speech processing. The relationship of rolandic (sylvian) seizure disorders with speech and cognitive impairments is well known, albeit poorly understood. We have identified the Xq22 gene SRPX2 as being responsible for rolandic seizures (RSs) associated with oral and speech dyspraxia and mental retardation (MR).

Reliability of individual functional MRI brain mapping of language.

The use of individual brain mapping for a single case study implicitly assumes that the pattern of activation obtained in a single session represents the subject's functional neuroanatomy. It is therefore essential to estimate the potential variability of brain activation in individuals. To this purpose, the authors compared the pattern of activation determined by statistical parametric mapping (SPM 99) in 9 subjects who repeated 3 verbal tasks in 3 separate sessions.

Unsupervised learning and mapping of active brain functional MRI signals based on hidden semi-Markov event sequence models.

In this paper, a novel functional magnetic resonance imaging (fMRI) brain mapping method is presented within the statistical modeling framework of hidden semi-Markov event sequence models (HSMESMs). Neural activation detection is formulated at the voxel level in terms of time coupling between the sequence of hemodynamic response onsets (HROs) observed in the fMRI signal, and an HSMESM of the hidden sequence of task-induced neural activations. The sequence of HRO events is derived from a continuous wavelet transform (CWT) of the fMRI signal.

Hidden Markov event sequence models: toward unsupervised functional MRI brain mapping.

Rationale And Objectives: Most methods used in functional MRI (fMRI) brain mapping require restrictive assumptions about the shape and timing of the fMRI signal in activated voxels. Consequently, fMRI data may be partially and misleadingly characterized, leading to suboptimal or invalid inference. To limit these assumptions and to capture the broad range of possible activation patterns, a novel statistical fMRI brain mapping method is proposed.

Can phonological and semantic short-term memory be dissociated? Further evidence from landau-kleffner syndrome.

Recent studies have made a distinction between short-term storage capacities for phonological information and short-term storage capacities for lexico-semantic information (R. Martin, Lesch, & Bartha, 1999). In this multiple case study, we tried to provide further evidence for the dissociability of phonological and lexico-semantic short-term memory (STM) components, by studying verbal STM in three patients who had recovered from Landau-Kleffner syndrome.

A cross-linguistic data bank for oral picture naming in Dutch, English, German, French, Italian, Russian, Spanish, and Swedish (PEDOI).

The well established effect of word frequency on adult's picture naming performance is now called into question. This is particularly true for variables which are correlated with frequency, as is the case of age of word acquisition. Since the work of [Carrol and White, 1973] there is growing agreement among researchers to confer an important role in lexical access to this variable.

Phonological short-term memory networks following recovery from Landau and Kleffner syndrome.

Landau-Kleffner syndrome (LKS) is a rare acquired aphasia occurring in otherwise healthy children, together with spike-wave discharges predominating over superior temporal regions and activated by sleep. Although the outcome of language abilities is variable, a residual impairment in verbal short-term memory (STM) is frequent. This STM deficit might be related to the persistent dysfunction of those temporal lobe regions where epileptic discharges were observed during the active phase of the disorder.

Semiology of typical and atypical Rolandic epilepsy: a video-EEG analysis.

Since the first descriptions of Rolandic Epilepsy or benign epilepsy with centrotemporal spikes (BECTS), typical and atypical forms have been reported. Indeed, classical focal seizures are sometimes associated with various atypical ictal symptoms and cognitive or behavioural disorders. In an effort to define early clinical and EEG criteria allowing early distinction between typical and atypical forms, we recently conducted a prospective study in a cohort of children with Rolandic Epilepsy.

[Cognitive consequences of Rolandic Epilepsy].

Idiopathic focal epilepsies and particularly rolandic epilepsy are considered to have an excellent outcome with spontaneous recovery during adolescence. The characterization of this syndrome in 1959 by Beaussart and Nayrac was a great progress for childhood epileptology: the existence of a focal epilepsy with a good prognosis and no underlying brain lesion, so-called "benign" epilepsy, was recognized. Since the first descriptions, numerous neuropsychological studies were performed showing variable results.

EEG criteria predictive of complicated evolution in idiopathic rolandic epilepsy.

Background: Although so-called "benign" epilepsy with centrotemporal spikes (BECTS) always has an excellent prognosis with regard to seizure remission, behavioral problems and cognitive dysfunctions may sometimes develop in its course. To search for clinical or EEG markers allowing early detection of patients prone to such complications, the authors conducted a prospective study in a cohort of unselected patients with BECTS.

Methods: In 35 children with BECTS, academic, familial, neurologic, neuropsychological, and wake and sleep EEG evaluations were repeated every 6 to 12 months from the beginning of the seizure disorder up to complete recovery.

Isotope tracer-techniques in rolandic epilepsy and its variants.

For ethical and practical reasons there are few studies on brain metabolism in rolandic epilepsy and it's variants. Most studies are performed in Landau-Kleffner syndrome or epilepsy with continuous spikes and waves during slow wave sleep (CSWS) which are considered to be included within the spectrum of rolandic epilepsy. The results of studies using isotope tracer-techniques in rolandic epilepsy and its variants are summarized.

Electrophysiological evidence of persisting unilateral auditory cortex dysfunction in the late outcome of Landau and Kleffner syndrome.

Objectives: In the late outcome of Landau and Kleffner syndrome (LKS), a childhood-acquired epileptic aphasia, most patients show after complete recovery of epilepsy a permanent one-ear extinction on dichotic listening tests contralateral to the temporal cortex previously affected by the epileptic focus. The pathophysiological significance of this dichotic extinction is not yet understood. It may be a consequence of a permanent dysfunction in the auditory system due to epileptic activity during the maturing period of the auditory system.