Cognitive and motor event-related potentials in Tourette syndrome and tic disorders: A systematic review

ObjectivesTourette syndrome (TS) patients face various cognitive and motor impairments. Event-related potentials (ERP) constitute an effective way to investigate the neural correlates of those functional impairments. Various components have been assessed among TS patients, with a wide variety of paradigms. This systematic review aimed to evaluate the portrait of ERP components in TS patients, and to understand the factors leading to discrepancies across studies.MethodsA literature search was performed in Embase, PsycINFO, Pubmed, and Web of Science, to identify studies that conducted ERP experiments among TS patients. Of the 372 unique records identified, 47 met inclusion criteria and were included in our systematic review.ResultsVarious ERP particularities were reported among included studies. Many discrepancies exist, but impairments in motor-related potentials and contingent negative variation seem constant across studies. Divergent findings point toward a possibly reduced P3b during oddball tasks.ConclusionsERPs offer an insightful investigation into the cognitive and motor functions of TS patients. Future studies should always control for confounding factors such as comorbidity, age, or medication status.SignificanceThis is the first systematic review of ERP in TS patients. Motor-related and slow cortical potentials could constitute electrophysiological markers of TS.     

Mouse cerebellar GABAB participation in the expression of acute ethanol-induced ataxia and in its modulation by the cerebellar adenosinergic A1 system

The possible modulation and of co-modulation by the cerebellar GABA_B and adenosine A₁ receptors of ethanol-induced motor impairment were investigated in the mice using rotorod performance as the test response. Direct cerebellar microinfusion of GABA_B agonist, baclofen, and antagonist, phaclofen, into the permanently cannulated mice, produced a dose-dependent accentuation and attenuation, respectively, of ethanol-induced motor impairment. The baclofen and phaclofen exhibited accentuation and attenuation, respectively, via GABA_B receptors linked to pertussis toxin-sensitive G protein. A co-modulation by the cerebellar adenosine A₁ receptors was also observed because intracerebellar microinfusion of adenosine agonists N⁶-cyclohexyladenosine (CHA), 5′-N-ethylcarboxamidoadenosine (NECA), and 2-p-(2-carboxyethyl)-phenyl-ethylamino-5′-N-ethylcarbox-amidoadenosine (CGS-21680), and antagonist, 8-cyclopentyl-1,3-dipropylxanthine (DPCPX), also accentuated and attenuated, respectively, ethanol-induced motor impairment. The accentuation of ethanol-induced motor impairment by baclofen was further enhanced after the intracerebellar microinfusion of CHA, suggesting a co-modulation by the co-localized adenosine A₁ receptors. A similar response was observed after the intracerebellar microinfusion of adenosine A₁ = A₂ agonist NECA and the several-fold higher dose of adenosine A₂-selective agonist CGS-21680. Ethanol-induced motor impairment was markedly blocked by intracerebellar A₁-selective antagonist, DPCPX, as well as by the intracerebellar pertussis toxin pretreatment suggesting again a co-modulation by the adenosine A₁ receptors and the involvement of pertussis toxin-sensitive G protein, respectively. The almost 25-fold higher dose of CGS-21680 to accentuate and DPCPX to attenuate, respectively, ethanol-induced motor impairment together with the reported cerebellar localization of adenosine A₁ subtype only, suggested A₁ receptor activation by NECA and CGS-21680. The functional similarity between GABA_B and adenosine A₁, receptors associated with their anatomical co-localization on the cerebellar granule cells, mainly axons and axonal terminals, may suggest a possible common adenylate cyclase catalytic unit as the basis of modulation of ethanol's motor impairment by these two receptor mechanisms.     

Effects of Exergame on Patients' Balance and Upper Limb Motor Function after Stroke: A Randomized Controlled Trial

Background: Stroke is a major cause of motor incapacity in adults and the elderly population, requiring effective interventions capable of contributing to rehabilitation. Different interventions such as use of exergames are being adopted in the motor rehabilitation and balance area, as they act as motivating instruments, making therapies more pleasurable. Objective: The aim of this study was to investigate the effects of exergame on patients’ balance and upper limb motor function after stroke. Methods: This study is a randomized controlled trial. Thirty-one participants of both genders, mean age of 76 years, were assigned to the experimental or control groups; the experimental group (n = 16) underwent exergame rehabilitation using Motion Rehab AVE 3D, and the control group (n = 15) underwent conventional physiotherapy. Both EG and GC sessions happened twice a week, for 30 minutes each, over a 12 weeks period, resulting in 24 sessions. All sessions were composed of similar exercises, with same purpose and elapsed time (5 minutes). Instruments applied to verify inclusion criteria were a sociodemographic questionnaire and clinical aspects and a Mini-Mental State Examination. At baseline and after 12 weeks of intervention, the Modified Ashworth Scale, the Fugl-Meyer Assessment, and the Berg Balance Scale were used. Results: In both groups, patients obtained significant improvement from baseline values in all analyzed variables (shoulder, elbow, and forearm; wrist; hand; and balance) (P < .001). In the intergroup comparison, there were significant differences between the 2 groups for changes in values from preintervention to postintervention of shoulder, elbow and forearm (P = .001), and total (P = .002). Conclusion: Exergame rehabilitation in poststroke patients can be an efficient alternative for restoring balance and upper limb motor function and might even reduce treatment time.     

Lisencefalia: Agiria: Un estudio con el metodo de Golgi

A case of lissencephaly (agyria) is reported in which the Golgi stain was used to study the fronto-parietal cortex. The external cellular layer, the so-called true cortex, was shown to be made up of neurons from the 5th and 6th layers of the normal cortex. The neurons in the much less cellular layer were shown to be large pyramidal cells with well-developed dendritic branching and spines. The deeper cellular layer was a neuronal pool without well-defined layering. All the neural forms from the normal cortex were represented. In this layer the inner neurons showed a less advanced stage of development than did those in the outer groups.In the external cellular layer there was a disorganization of neuronal disposition as well. Otherwise typical large and medium-sized pyramidal cells from the outer third showed apical dendrites directed towards deeper structures, and the basal dendrites ran through the marginal layer. Neurons with double dendritic branching and fusiform neurons were present in an abnormal rotated position. In both cases, the axons always showed a descending direction.These findings add to existing knowledge concerning the anatomy of the lissencephalic cortex, although the exact interpretation of the abnormalities found in the external cellular layer remains speculative.     

Determinants of motor unit action potential duration.

OBJECTIVE: Motor unit action potential (MUAP) recordings are modeled by means of a single muscle fiber simulation program, to define two key subcomponents comprising the complete physiologic MUAP duration. A number of defining properties of these subcomponents are further developed. METHODS: A single muscle fiber simulation program is utilized with various muscle fiber lengths and conduction velocities to generate near-field and far-field waveforms. RESULTS: Two key subcomponents to the total physiologic single muscle fiber and hence MUAP duration are identified. One, defined as the near-field component, is directly dependent upon muscle fiber hemi-length. The other, defined as the far-field component, is independent of fiber length, but matches the internal action potential in duration. Both the near-field and far-field components are inversely dependent upon intracellular action potential conduction velocity. Additionally, temporal dispersion among the individual fibers contributing to a MUAP must be included in the overall MUAP duration calculation. CONCLUSIONS: It is hoped that this approach to MUAP duration may allow a more complete appreciation of the components contributing to the MUAP, than permitted by the empirically derived values for MUAP duration presently under clinical use.     

脑梗死患者交感神经皮肤反应分析

交感神经皮肤反应（sympathetic skin response,SSR）是由内源或外源性刺激所诱发的皮肤 瞬时电位变化,属于脑和脊髓参与的交感催汗运动。本文主要概述近年来SSR在脑梗死患者中应用 价值,阐述其对脑梗死患者自主神经功能紊乱的临床诊断作用,与脑梗死患者运动功能的相关性, 以及SSR在推断交感神经可能的中枢传导通路中的价值。     

Crossed aphasia in dextrals: a case report with special reference to site of lesion

A strictly right-handed man showed aphasia and left hemiplegia following a deep infarct of the right hemisphere. Aphasic semeiology was characterized by an oral and written jargon while comprehension was almost intact. Several hypotheses previously put forward fail to account for the patient's aphasia. Emphasizing the frequency of deep structures involvement in the published cass of crossed dextral aphasias, it is suggested that site of lesion may have a certain part to play in the occurrence of such aphasias.     

Extensive form of progressive multifocal leucoencephalopathy associated with laryngeal carcinoma

Summary A case is reported of the rare association between progressive multifocal leucoencephalopathy and carcinoma. A 66-year-old man underwent a laryngectomy for carcinoma. Four years later he developed a local recurrence. Simultaneously there were behavioural disturbances and a left motor neglect followed by dense hemiplegia and coma. The patient died a further 5 months later. Anergy was demonstrated by skin tests. CT scan showed asymmetrical non-enhancing low-density areas in the hemispheric white matter, brain-stem and cerebellum and neuropathological examination confirmed extensive myelin loss with typical papovavirus inclusions in oligodendrocytes identified by electron microscopy.Presented at the Irish Neurological Association and Danish Neurological Society joint meeting, Cork, 16 May 1985