Modulation of neuronal activity in human centromedian nucleus during an auditory attention and working memory task.

Centromedian nucleus (CM) is one of several intralaminar nuclei of the thalamus and is thought to be involved in consciousness, arousal, and attention. CM has been suggested to play a key role in the control of attention, by regulating the flow of information to different brain regions such as the ascending reticular system, basal ganglia, and cortex. While the neurophysiology of attention in visual and auditory systems has been studied in animal models, combined single unit and LFP recordings in human have not, to our knowledge, been reported. Here, we recorded neuronal activity in the CM nucleus in 11 patients prior to insertion of deep brain stimulation electrodes for the treatment of epilepsy while subjects performed an auditory attention task. Patients were requested to attend and count the infrequent (p = 0.2) odd or "deviant" tones, ignore the frequent standard tones and report the total number of deviant tones at trial completion. Spikes were discriminated, and LFPs were band pass filtered (5-45 Hz). Average peri­stimulus time histograms and spectra were constructed by aligning on tone onsets and statistically compared. The firing rate of CM neurons showed selective, multi-phasic responses to deviant tones in 81% of the tested neurons. Local field potential analysis showed selective beta and low gamma (13-45 Hz) modulations in response to deviant tones, also in a multi-phasic pattern. The current study demonstrates that CM neurons are under top-down control and participate in the selective processing during auditory attention and working memory. These results, taken together, implicate the CM in selective auditory attention and working memory and support a role of beta and low gamma oscillatory activity in cognitive processes. It also has potential implications for DBS therapy for epilepsy and non-motor symptoms of PD, such as apathy and other disorders of attention.

Tratamiento del estado epiléptico, consenso de expertos. Asociación Colombiana de Neurología, Comité de Epilepsia / Treatment of status epilepticus, an expert consensus report. Colombian Neurology Association - Epilepsy Committee

RESUMEN INTRODUCCIÓN: El estado epiléptico (EE) es una condición ocasionada por la falla en los mecanismos de supresión de las crisis epilépticas. Se considera como una urgencia neurológica y obliga al profesional de la salud a conocer las características de presentación para poder estabilizar al paciente. La mortalidad varía entre el 2 % y el 50 % según el grupo etario. OBJETIVO: Construir una serie de sugerencias para el tratamiento del EE, como resultado del consenso por común acuerdo de expertos en epilepsia, teniendo en cuenta el contexto colombiano. MÉTODOS: Se llevó a cabo un consenso formal de expertos con 16 neurólogos-epileptólogos de adultos y niños. Las preguntas y sugerencias fueron revisadas en dos fases, donde fueron calificadas y consensuadas por los participantes. RESULTADOS: Se evaluaron 15 preguntas, con sus respectivas sugerencias sobre el manejo del estado epiléptico, se tuvieron en cuenta referencias bibliográficas relevantes consideradas por los expertos y de acuerdo con el contexto colombiano. CONCLUSIONES: Los resultados de este consenso presentan una serie de sugerencias para el tratamiento del estado epiléptico tanto en los primeros niveles de atención como en los de alta complejidad para mejorar el pronóstico del paciente, de acuerdo con el contexto colombiano.

SUMMARY INTRODUCTION: Status epilepticus is a condition caused by failure in the mechanisms of suppression of epileptic seizures. It is considered a neurological emergency, and mortality varies between 2 % to 50 % according to the age group. Due to the above, it is relevant that health professionals know the characteristics of SE in order to stabilize the patient. OBJECTIVE: To define a series of propositions for the treatment of SE, as a result of consensus by common agreement of experts in epilepsy, taking into account the Colombian context. METHODS: A formal consensus of experts was carried out with 16 adult and pediatric neurologists-epilep-tologists. The questions and propositions were reviewed in two phases, where they were graded and agreed by the participants. RESULTS: Fifteen questions were evaluated on the management of status epilepticus. Relevant bibliographic references were considered by the experts according to the Colombian context. CONCLUSIONS: As results of this consensus we present a series of propositions for the treatment of status epilepticus for the primary level of care and high complexity level of care in order to improve the patient's prognosis, according to the Colombian context.

Neurosífilis meningovascular con trombosis de la arteria basilar / Meningovascular neurosyphilis with basilar artery thrombosis, a case report and literature review

Se presenta el caso clínico de un paciente de 54 años, negativo para VIH, con enfermedad cerebrovascular por trombosis de la arteria basilar, secundaria a neurosífilis meningovascular. La neurosífilis es el compromiso del sistema nervioso central por Treponema pallidum subespecie pallidum en cualquier estadio de la entidad e incluye las formas asintomáticas y sintomáticas de la infección; sus formas de presentación son diversas y dependen de la localización y la extensión de las lesiones. La recomendación actual es el tratamiento con 4 millones de unidades de penicilina cristalina cada 4 horas por 14 días.

Herein a case is described of a 54-years old patient, HIV negative, with cerebro-vascular disease by basilar artery thrombosis secondary to meningovascular neurosyphilis. Neurosyphilis is the impairment at any stage of the central nervous system by Treponema pallidum subspecies pallidum and includes asymptomatic and symptomatic forms of infection. The presentation can take many forms, depending on the location and extent of tissue damage. The currently recommended treatment is crystalline penicillin, 4 million units every 4 hours for 14 days.