TROPONIN LEVELS IN TRANSIENT ISCHEMIC ATTACK AND ISCHEMIC STROKE: DOES "TRANSIENT" IN YOUR BRAIN MEAN "BETTER" FOR YOUR HEART?

PURPOSE: transient ischemic attack (TIA) is defined as a transient episode of neurological dysfunction caused by focal brain, spinal cord, or retinal ischemia, with clinical symptoms typically lasting less than one hour, and without evidence of acute infarction. In this type of ischemic event, there are no data about a possible cardiac injury tested with troponin. After a stroke, it is well established the cardiac involvement due to a neuro-inflammatory response (recently defined as Stroke Heart Syndrome). The aim of this study is to compare the troponin elevation after a stroke with TIA. MATERIALS AND METHODS: this is a retrospective, single center study on 565 patients (73 TIAs, 492 stroke). We collected demographic characteristics, cardiovascular risk factors, cardiac data such as troponin, NT-proBNP, left atrial dilatation, etiology of the ischemic event (TOAST classification). RESULTS: we compare IS and TIA for each TOAST subtype. In all groups no substantial differences were found in demographic and past medical history (p>0.05). However, the maximum troponin level reached were significantly lower in TIAs than IS (p<0.05), except in lacunar etiology were troponin elevation was low also in IS group. We found a trend in favor to IS in the rise and fall troponin elevation over 30% in all the TOAST subgroups, but only in the cryptogenic etiology the difference was significant. About the others cardiac markers of injury, a significant higher rate of elevated NT-proBNP was found in the IS cohort. CONCLUSIONS: troponin level after TIAs is significantly lower than after IS. Troponin elevation after an ischemic event may be more relevant in patients with higher NT-proBNP levels and older age. More studies are needed to better understand the patho-physiology of this phenomenon after an ischemic event.

Telemedicine during the SARS-Cov-2 pandemic lockdown: Monitoring stress and quality of sleep in patients with epilepsy.

SARS-CoV-2 pandemic heavily hit the western healthcare system saturating the hospital beds in wards and clogging the emergency departments. To avoid the collapse of Italian hospitals, office visits to outpatients were limited to emergencies and the general population went in a lockdown state. Physicians had to approach new problems in the management of chronic patients who could not leave their homes. In our experience as epilepsy clinic, the use of telemedicine was of crucial importance for monitoring our patients: phone call during lockdown let us monitor the stability of our 38 patients and psychometric parameters and habits that could influence seizures frequency. In particular, we found that in our patients, sleep quality was low resulting in high daily sleepiness and associated high stress levels. Secondly, we found an increase in daily screen hours and an association with daily sleepiness. In conclusion, we report our experience in managing people with epilepsy during the lockdown, underlining the utility of telemedicine as a valid monitoring tool and the necessity of a psychometric and behavioral screening.

Epilepsy in multiple sclerosis: The role of temporal lobe damage.

BACKGROUND: Although temporal lobe pathology may explain some of the symptoms of multiple sclerosis (MS), its role in the pathogenesis of seizures has not been clarified yet. OBJECTIVES: To investigate the role of temporal lobe damage in MS patients suffering from epilepsy, by the application of advanced multimodal 3T magnetic resonance imaging (MRI) analysis. METHODS: A total of 23 relapsing remitting MS patients who had epileptic seizures (RRMS/E) and 23 disease duration matched RRMS patients without any history of seizures were enrolled. Each patient underwent advanced 3T MRI protocol specifically conceived to evaluate grey matter (GM) damage. This includes grey matter lesions (GMLs) identification, evaluation of regional cortical thickness and indices derived from the Neurite Orientation Dispersion and Density Imaging model. RESULTS: Regional analysis revealed that in RRMS/E, the regions most affected by GMLs were the hippocampus (14.2%), the lateral temporal lobe (13.5%), the cingulate (10.0%) and the insula (8.4%). Cortical thinning and alteration of diffusion metrics were observed in several regions of temporal lobe, in insular cortex and in cingulate gyrus of RRMS/E compared to RRMS ( p< 0.05 for all comparisons). CONCLUSIONS: Compared to RRMS, RRMS/E showed more severe damage of temporal lobe, which exceeds what would be expected on the basis of the global GM damage observed.

Acute myelitis as presenting symptom of HIV-HTLV-1 co-infection.

A 21-year-old woman presented with acute-onset spastic paraparesis. The MRI spinal scan revealed a contrast-enhanced T2 hyperintensity between C5-T2. The most common neurotropic pathogens were excluded by first level tests. Under suspicion of an acute immune-mediated myelitis, a corticosteroid therapy was administered. However, a seropositivity for both human immunodeficiency virus (HIV) type 1 and human T-lymphotropic virus (HTLV) subsequently emerged. An antiretroviral therapy was started while steroids discontinued. Patient's clinical conditions remained unchanged. HIV-HTLV-1 co-infection should be included in the differential diagnosis of any acute myelitis, even in patients with a preserved immune status and no risk factors.

Omics sciences and precision medicine in glioblastoma.

Abstract: Glioblastoma is a highly aggressive and malignant type of brain cancer with a poor prognosis, despite current treatment options of surgery, radiation therapy, and chemotherapy. These treatments have limitations due to the aggressive nature of the cancer and the difficulty in completely removing the tumor without damaging healthy brain tissue. Personalized medicine, using genomic profiling to tailor treatment to the patient's specific tumor, and immunotherapy have shown promise in clinical trials. The blood-brain barrier also poses a challenge in delivering treatments to the brain, and researchers are exploring various approaches to bypass it. More effective, personalized treatment approaches are needed to improve outcomes for glioblastoma patients. This tumor is studied using genomics, transcriptomics, and proteomics techniques, to better understand its underlying molecular mechanisms. Recent studies have used these techniques to identify potential therapeutic targets, molecular subtypes, and heterogeneity of tumor cells. Advancements in omics sciences have improved our understanding of glioblastoma biology, and precision medicine approaches have impli-cations for more accurate diagnoses, improved treatment outcomes, and personalized preventive care. Precision medicine can match patients with drugs that target specific genetic mutations, improve clinical trials, and identify individuals at higher risk for certain diseases. Precision medicine, which involves customizing medical treatment based on an individual's genetic makeup, lifestyle, and environmental factors, has shown promise in improving treatment outcomes for glioblastoma patients. Identifying biomarkers is essential for patient stratification and treatment selection in precision medicine approaches for glioblastoma, and several biomarkers have shown promise in predicting patient response to treatment. Targeted therapies are a key component of precision medicine approaches in glioblastoma, but there is still a need to improve their effectiveness. Technical challenges, such as sample quality and availability, and challenges in analyzing and interpreting large amounts of data remain significant obstacles in omics sciences and precision medicine for glioblastoma. The clinical implementation of precision medicine in glioblastoma treatment faces challenges related to patient selection, drug development, and clinical trial design, as well as ethical and legal considerations related to patient privacy, informed consent, and access to expensive treatments.

Serum proteomic profiling reveals potential inflammatory biomarkers in long-COVID patients: a comparative analysis with healthy controls.

OBJECTIVE: The highly transmissible severe acute respiratory syndrome-Coronavirus-2 was responsible for the 2020 COVID-19 pandemic. COVID-19 mostly affects the respiratory system; however, this infection also affects several other organs. In addition, the sequelae of this disease affect patients for several months after recovery, resulting in long-COVID syndrome. PATIENTS AND METHODS: In order to characterize the differences between healthy control individuals and long-COVID patients, proteomic profiling of the serum of both groups was performed by mass spectrometry. The obtained data were analyzed with multivariate and univariate statistical analyses. RESULTS: Initially, performing a partial latent square discriminant analysis (PLS-DA) made it possible to identify thirty-three proteins of interest, which were then subjected to a receiver operating characteristic (ROC) analysis. Four proteins were identified as potential stand-alone biomarkers: Sirtuin 1, Natriuretic Peptide B, Hemopexin, and Arachidonate 5-Lipoxygenase. Moreover, a multivariate ROC analysis identified a panel of biomarkers composed of Natriuretic Peptide B, Anterior Gradient 2 Protein, Adiponectin, Endothelin Converting Enzyme 1, Interferon Induced Transmembrane Protein 1, Mannose Binding Lectin 2, Prostaglandin-Endoperoxide Synthase 2, Pirin, Prostaglandin Reductase 1 and Cystatin C. CONCLUSIONS: The identified biomarkers are associated with inflammatory processes, corroborating literature evidence that long-COVID patients develop an inflammatory state that damages many tissues. Nevertheless, these data should be validated in a larger cohort.

Linking pathogenic and likely pathogenic gene variants to long-COVID symptoms.

OBJECTIVE: Long-COVID is a clinical syndrome characterized by the presence of symptoms related to SARS-CoV-2 infection that persist for at least four weeks after recovery from COVID-19. Genetics have been proposed to play an important role in long-COVID syndrome onset. This study aimed to identify genetic pathogenetic and likely pathogenetic causative variants of Mendelian genetic diseases in patients with Long-COVID syndrome. Additionally, we aimed to establish an association between these genetic variants and the clinical symptoms manifested during long-COVID syndrome. PATIENTS AND METHODS: 95 patients affected by long-COVID syndrome were analyzed with a Next-Generation Sequencing (NGS) panel comprising 494 genes. The analyzed genes and the symptoms of the patients collected with an ad-hoc questionnaire were divided into four groups (cardiological, respiratory, immunological, and neurological). Finally, a statistical analysis comprising descriptive statistics, classification based on reported symptoms, and comparative analysis against a control group of healthy individuals was conducted. RESULTS: 12 patients resulted positive for genetic testing with an autosomal dominance (8) or autosomal recessive (4) inheritance, showing a higher prevalence of cardiovascular genetic diseases (9) in the analyzed cohort compared to the normal population. Moreover, the onset of the long-COVID syndrome and its cardiovascular manifestations was compliant with the onset reported in the literature for the identified genetic diseases, suggesting that COVID-19 could manifest late-onset genetic diseases associated with their appearance. Apart from the 12 positive patients, 57 were healthy carriers of genetic diseases. Analyzing the whole cohort, a statistical correlation between prevalent symptomatology and the gene class was established, suggesting an association between the genetic susceptibility of an individual and the possibility of developing specific long-COVID syndrome symptoms, especially cardiovascular symptoms. Furthermore, 17 genetic variants were identified in CFTR. Finally, we identified genetic variants in IFNAR2 and POLG, supporting their respective involvement in inflammation and mitochondria mechanisms, correlated with long-COVID syndrome according to literature data. CONCLUSIONS: This study proposed COVID-19 to act as a manifest of underlying late-onset genetic diseases Mendelian associated with carrier status. Moreover, according to our results, mutations in cardiological genes are more present in patients who show cardiological symptoms during the syndrome. This underscores the necessity for cardiological investigation and genetic screening in long-COVID patients to address existing or potential clinical implications.

Deep brain stimulation of the subthalamic nucleus and the temporal discounting of primary and secondary rewards.

Although deep brain stimulation of the subthalamic nucleus is an effective surgical treatment for Parkinson's disease, it may expose patients to non-motor side effects such as increased impulsivity and changes in decision-making behavior. Even if several studies have shown that stimulation of the subthalamic nucleus increases the incentive salience of food rewards in both humans and animals, temporal discounting for food rewards has never been investigated in patients who underwent STN-DBS. In this study, we measured inter-temporal choice after STN-DBS, using both primary and secondary rewards. In particular, PD patients who underwent STN-DBS (in ON medication/ON stimulation), PD patients without STN-DBS (in ON medication) and healthy matched controls (C) performed three temporal discounting tasks with food (primary reward), money and discount vouchers (secondary rewards). Participants performed also neuropsychological tests assessing memory and executive functions. Our results show that STN-DBS patients and PD without DBS behave as healthy controls. Even PD patients who after DBS experienced weight gain and/or eating alterations did not show an increased temporal discounting for food rewards. Interestingly, patients taking a higher dosage of dopaminergic medications, fewer years from DBS surgery and, unexpectedly, with better episodic memory were also those who discounted rewards more. In conclusion, this study shows that STN-DBS does not affect temporal discounting of primary and secondary rewards. Furthermore, by revealing interesting correlations between clinical measures and temporal discounting, it also shed light on the clinical outcomes that follow STN-DBS in patients with PD.

Motor cortical disinhibition during early and late recovery after stroke.

BACKGROUND: Functional neuroimaging studies show adaptive changes in areas adjacent and distant from the stroke. This longitudinal study assessed whether changes in cortical excitability in affected and unaffected motor areas after acute stroke correlates with functional and motor recovery. METHODS: We studied 13 patients with moderate to severe hemiparesis 5 to 7 days (T1), 30 days (T2), and 90 days (T3) after acute unilateral stroke, as well as 10 healthy controls. We used paired-pulse transcranial magnetic stimulation to study intracortical inhibition and facilitation, recording from the bilateral thenar eminences. F waves were also recorded. RESULTS: At T1, all patients showed significantly reduced intracortical inhibition in the unaffected hemisphere. At T2, in patients whose motor function recovered, intracortical inhibition in the unaffected hemisphere returned to normal. In patients with poor clinical motor recovery, abnormal disinhibition persisted in both hemispheres. At T3, in patients whose motor function progressively recovered, the abnormal disinhibition in the unaffected hemisphere decreased further, whereas in patients whose motor function remained poor, abnormal inhibition in the unaffected hemisphere persisted. No modification of F-wave latency and amplitude were found in patients and controls. CONCLUSIONS: During early days after stroke, motor cortical disinhibition involves both cerebral hemispheres. Longitudinal changes in motor disinhibition of the unaffected hemisphere may reflect the degree of clinical motor recovery.

The use ultrasound guided for refilling intrathecal baclofene pump in complicated clinical cases: A practical approach.

Muscular spasticity due to neurological disorders is a heavy cause of severe pain and disability for many patients, compromising the independence and quality life. Baclofene is a good tool to guarantee patients independence and pain control. Anyway in chronic therapy oral treatment become unsatisfactory. In all these cases, intrathecal baclofen therapy (ITB), after sub fascial implantation of intrathecal pumps is used as an important long term treatment to reduce spasticity. After pump implantation the drug reservoir must be refilled periodically in order to maintain the reduction of spasticity and avoid the symptoms and signs of withdrawal. ITB refilling, which involves the insertion of a needle through the skin until the access port of the pump, is often hard, mainly due to the layer of abdominal fat, spasticity, suboptimal pump positioning, pump rotation or inversion, and scar formation over the implantation site. To avoid the difficulties of ITB refilling radiography or other invasive supportive examinations are sometimes needed. We reported here our experience and we suggest a simple method to use the ultrasound in refilling with particular attention to some cases with complications after implantation with a difficult approach in refilling. We used the ultrasound examination to identify the access port of her pump so as to avoid multiple needle punctures and infections and radiation exposition. Ultrasound-guided technique may facilitate ITB refill in technically challenging cases. With ultrasound ITB was easily detectable and was quite simple to identify the exact point of needle injection. In the last years different new applications for ultrasounds are emerging. In our opinion the use of Doppler ultrasounds in the study of muscles and nerves represent an emerging tool for the physician's neurological rehabilitation.

Monitoring of motor pathways during brain stem surgery: what we have achieved and what we still miss?

Intraoperative neurophysiological monitoring (IOM) has established itself as one of the paths by which modern neurosurgery can improve surgical results while minimizing morbidity. IOM consists of both monitoring (continuous "on-line" assessment of the functional integrity of neural pathways) and mapping (functional identification and preservation of anatomically ambiguous nervous tissue) techniques. In posterior-fossa and brainstem surgery, mapping techniques can be used to identify - and therefore preserve - cranial nerves, their motor nuclei and corticospinal or corticobulbar pathways. Similarly, free-running electromyography (EMG) and muscle motor-evoked potential (mMEP) monitoring can continuously assess the functional integrity of these pathways during surgery. Mapping of the corticospinal tract, at the level of the cerebral peduncle as well as mapping of the VII, IX-X and XII cranial nerve motor nuclei on the floor of the fourth ventricle, is of great value to identify "safe entry-zones" into the brainstem. Mapping techniques allow recognizing anatomical landmarks such as the facial colliculus, the hypoglosseal and glossopharyngeal triangles on the floor of the fourth ventricle, even when normal anatomy is distorted by a tumor. On the basis of neurophysiological mapping, specific patterns of motor cranial nuclei displacement can be recognized. However, brainstem mapping cannot detect injury to the supranuclear tracts originating in the motor cortex and ending on the cranial nerve motor nuclei. Therefore, monitoring techniques should be used. Standard techniques for continuously assessing the functional integrity of motor cranial nerves traditionally rely on the evaluation of spontaneous free-running EMG in muscles innervated by motor cranial nerves. Although several criteria have been proposed to identify those EMG activity patterns that are suspicious for nerve injury, the terminology remains somewhat confusing and convincing data regarding a clinical correlation between EMG activity and clinical outcome are still lacking. Transcranial mMEPs are also currently used during posterior-fossa surgery and principles of MEP monitoring to assess the functional integrity of motor pathways are similar to those used in brain and spinal-cord surgery. Recently, current concepts in muscle MEP monitoring have been extended to the monitoring of motor cranial nerves. So-called "corticobulbar mMEPs" can be used to monitor the functional integrity of corticobulbar tracts from the cortex through the cranial motor nuclei and to the muscle innervated by cranial nerves. Methodology for this purpose has appeared in the literature only recently and mostly with regards to the VII cranial nerve monitoring. Nevertheless, this technique has not yet been standardized and some limitations still exist. In particular, with regards to the preservation of the swallowing and coughing reflexes, available intraoperative techniques are insufficient to provide reliable prognostic data since only the efferent arc of the reflex can be tested.

Repetitive magnetic stimulation of the sacral roots for the treatment of stress incontinence: a brief report.

AIM: The aim of this study was to investigate the short and long-term effects of repetitive magnetic stimulation on the sacral roots in a homogeneous group of patients affected by stress incontinence. METHODS: Twenty women with urinary stress incontinence were randomly assigned to an active or a sham stimulation group. Fifteen-Hz repetitive magnetic stimulation of the sacral roots (S2-S4) was applied for 15 min. Patients were treated with magnetic stimulation for 3 days a week for 2 weeks (6 times in all). The clinical outcome was assessed before (T1) and 1 week (T2) and 1 month (T3) after stimulation. Main outcome measures were: the King's Health Questionnaire, the SEAPI-QMM scale and the amount of urinary loss in a 1-h pad test and stress test. RESULTS: At T2 patients in the active stimulation group showed improvement in health perception (P<0.001), social limitation (P<0.01), sleep/energy performance (P<0.05) and severity measure score (P<0.05) not observed in the sham stimulation group; a significant decrease in SEAPI-QMM score was noted only in the active group at T2 (P<0.05). These results were no longer observed at T3. We also observed a decrease in the amount of urine loss quantified with the pad test and stress test in the active stimulation group. CONCLUSION: Repetitive magnetic stimulation of the sacral roots has a short-term effect on some aspects of the quality of life of the patients, but it did not prove effective using quantified measurement.

Long-term effect of shock wave therapy on upper limb hypertonia in patients affected by stroke.

BACKGROUND AND PURPOSE: Spasticity is a disabling complication of stroke and different noninvasive treatments are used to reduce muscle hypertonia. Shock waves are defined as a sequence of single sonic pulses largely used in the treatment of diseases involving bone and tendon as well as muscular contractures. The effect and duration of extracorporeal shock wave therapy (ESWT) was investigated on muscle hypertonia of the hand and wrist. METHODS: A total of 20 patients affected by stroke associated with severe hypertonia in upper limbs were evaluated. Placebo stimulation was performed 1 week before active stimulation in each patient. Evaluation was performed using the National Institutes of Health and Ashworth scales and video monitoring with a digital goniometer before and immediately after placebo or active stimulation. Motor nerve conduction velocity from abductor digiti minimi were recorded. Patients were monitored at 1, 4, and 12 weeks after active treatment. RESULTS: After active ESWT, patients showed greater improvement in flexor tone of wrist and fingers compared with placebo stimulation. At the 1- and 4-week follow-up visits, a significant decrease of passive muscle tonicity was noted on muscles in all patients receiving active treatment. At 12 weeks after therapy, 10 of the 20 patients showed persistent reduction in muscle tone. There were no adverse events associated with ESWT. CONCLUSIONS: ESWT reduces hypertonia of the wrist and finger muscles for > or =12 weeks after treatment. The possible mechanisms of action of ESWT are discussed.

Hyperexcitable cortical responses in progressive myoclonic epilepsy: a TMS study.

OBJECTIVE: Transcranial magnetic stimulation (TMS) has allowed investigators to study intracortical inhibition and facilitation and sensorimotor integration in motor disorders and epilepsy. The authors used TMS to elucidate the pathophysiology of reflex myoclonus with giant somatosensory evoked potentials (SEP). METHODS: The authors studied four patients with progressive myoclonic epilepsy. All patients had giant SEP elicited by mixed and digital nerve stimulation. They studied the response to paired-pulse TMS at interstimulus intervals (ISI) ranging from 1 to 15 ms and the conditioning effect of digital electrical stimulation at ISI ranging from 10 to 100 ms on the motor evoked potential amplitude to TMS. RESULTS: Digital stimulation markedly facilitated conditioned motor evoked potentials at ISI ranging from 25 to 40 ms in all patients. This pattern was significantly different from the inhibition observed in controls (n = 12) at the same ISI. In the patients, paired-pulse TMS showed a decrease in intracortical inhibition in the motor cortex in comparison with controls. CONCLUSIONS: These findings suggest cortical and subcortical components of abnormal sensorimotor integration in addition to hyperexcitability of the sensory and motor cortex in our myoclonic patients.

Effects of voluntary contraction on tibial nerve somatosensory evoked potentials: gating of specific cortical responses.

We evaluated vertex-parietal P37, N50, and contralateral N37 somatosensory evoked potentials (SEPs) to posterior tibial nerve stimulation during weak (20 to 30%) and strong (80 to 90%) ipsilateral gastrocnemius-soleus contraction. The results were compared with data obtained during full relaxation. P37 and N50 were attenuated significantly during weak contraction and then abolished during strong contraction, whereas the contralateral N37 was not. The N37 potential spreads over the vertex and over the ipsilateral parietal region during strong contraction. The Cz'-F3 montage was not appropriate for detecting these SEP patterns. These findings suggest that thalamic or cortical gating mechanisms affect specific cortical responses. P37 and N50 could reflect the arrival of the afferent volley into the motor areas from thalamic and cortical (subareas 1 and 2 of S1) projections. N37 could be generated in subarea 3b. Differential analysis of N37 and P37 is required in clinical practice, mainly in those conditions that involve the motor system and in those conditions in which tonic muscular activity is increased.

Sensory involvement in X-linked spino-bulbar muscular atrophy (Kennedy's syndrome): an electrophysiological study.

Electrophysiological findings were studied in a family with spino-bulbar muscular atrophy (SBMA): the subjects were three male patients aged 58, 38 and 34 years and two female carriers aged 63 and 28 years. Diagnosis was proven at the molecular genetic level. Electromyography in the males showed spontaneous activity and neurogenic reorganization of the motor unit; motor nerve conduction was normal. Sensory action potentials were variably reduced in amplitude, but some were completely normal. Somatosensory evoked potentials, from both the upper and lower limbs, were invariably abnormal because involvement of the central pathways was observed. These findings are in agreement with histological investigations documenting lesions in the posterior columns. Brain-stem acoustic evoked potentials showed an increase in wave I latency. The electrophysiological data provide further evidence of the extent of sensory damage either in the central or the peripheral nervous system in SBMA patients, who otherwise have a constant clinical presentation of progressive motor neuron disease.

Contribution of motor cortex in generation of evoked spikes in patients with benign rolandic epilepsy.

OBJECTIVES: Among the different kinds of rolandic epilepsy there is a form of benign epilepsy with centrotemporal spikes (BECT) presenting the peculiar characteristic of evoking rolandic paroxysmal activity, characterized by a spike followed by a slow wave, using electrical stimulation of the fingers. METHODS: We evaluated 7 patients suffering from BECT presenting evoked scalp activity by electrical stimulation of the fingers of the hand. Electrical stimulation was performed using a pair of ring electrodes applied to the thumb. The motor evoked potentials (MEPs) were elicited in hand muscles by transcranial magnetic stimulation (TMS) and were conditioned by the same electrical digital stimulation producing the evoked spikes at interstimulus intervals ranging from 10 to 200 ms. RESULTS: Digital stimulation in epileptic patients produced an increase in MEP amplitude substantially above the normal ranges. MEP facilitation showed a time course overlapping the ascending phase and peak of the evoked spike, whereas no significant MEP changes were found during the early positive peak and the descending phase of the spike, or during the following slow wave. CONCLUSIONS: Several considerations support the hypothesis that the short-lasting M1 facilitation is related to the spread of an abnormal hypersynchronous discharge of the S1 neurones to functionally related motor areas via cortico-cortical connections.

Motor disinhibition in affected and unaffected hemisphere in the early period of recovery after stroke.

OBJECTIVES: To investigate motor disinhibition in affected and unaffected motor areas in the acute stage after stroke and during the early period of recovery. METHODS: Fifteen patients with moderate to severe hemiparesis after acute unilateral stroke were compared with 10 healthy age-matched controls. We used paired transcranial magnetic stimulation to study intracortical inhibition and facilitation from the thenar eminence muscles on both sides. F-wave from the median nerve on both sides were recorded. The recordings were performed 5-7 days (T1) and 30 days after stroke. RESULTS: In 10 patients who showed the presence of reliable motor evoked potentials on the affected side, intracortical inhibition was significantly reduced. On the unaffected side intracortical inhibition (ICI) was significantly reduced in all patients. Patients who presented significant motor recovery after 30 days showed persistence of abnormal disinhibition in the affected hemisphere but a return to normal ICI in the unaffected hemisphere. Patients with poor motor recovery showed persistence of abnormal disinhibition on both sides. No significant changes were observed in F-wave amplitude. CONCLUSIONS: Motor disinhibition occurs on both sides after stroke in all acute stage patients. Changes in motor disinhibition on unaffected side also are related to motor recovery.

Decrease in motor cortical excitability in human subjects after sleep deprivation.

The effect of sleep deprivation on human motor cortical excitability was investigated by evaluating the changes in motor evoked potentials from the thenar eminence muscles of the right hand in seven subjects. Motor threshold, motor evoked potential amplitude, silent period, intracortical inhibition, intracortical facilitation and F wave were studied. Recordings were performed every 6 h during the day-time (from 09.00 to 21.00 h) and every 3 h during the night-time (from 21.00 to 09.00 h). Significant increases in motor threshold, intracortical inhibition and silent period were noted in the recordings during the night associated with a return to baseline values in the morning. No significant changes were observed in any of the other parameters. Enhancement of intracortical motor inhibition is suggested to explain the effect of sleep deprivation.