Left Motor Area Research Articles

Neural correlates of proprioceptive upper limb position matching.

Proprioceptive information allows humans to perform smooth coordinated movements by constantly updating one's mind with knowledge of the position of one's limbs in space. How this information is combined with other sensory modalities and centrally processed to form conscious perceptions of limb position remains relatively unknown. What has proven even more elusive is pinpointing the contribution of proprioception in cortical activity related to motion. This study addresses these gaps by examining electrocortical dynamics while participants performed an upper limb position matching task in two conditions, namely with proprioceptive feedback or with both visual and proprioceptive feedback. Specifically, we evaluated the reduction of the electroencephalographic power (desynchronization) in the μ frequency band (8-12 Hz), which is known to characterize the neural activation associated with motor control and behavior. We observed a stronger desynchronization in the left motor and somatosensory areas, contralateral to the moving limb while, parietal and occipital regions, identifying association and visual areas, respectively, exhibited a similar activation level in the two hemispheres. Pertaining to the influence of the two experimental conditions it affected only movement's offset, and precisely we found that when matching movements are performed relying only on proprioceptive information, a lower cortical activity is entailed. This effect was strongest in the visual and association areas, while there was a minor effect in the hand motor and somatosensory areas.

Contribution of left frontal-motor alpha phase synchronization to semantic inhibition in obsessive–compulsive tendencies

Patients with obsessive-compulsive disorder attempt to suppress obsessions and/or compulsions. Although previous psychological research suggests reduced semantic inhibition in such patients, no research has explored the underlying neural mechanisms of semantic control in patients with obsessive-compulsive disorder. In addition to semantic representation, semantic control also generates task-relevant behaviors. Previous research has implicated the left frontal and posterior temporal areas in semantic control; however, no research approaches the dynamic relationships among task-relevant brain areas. To address this, we investigated the phase synchronizations among these areas using time-frequency analysis of data from an electroencephalograph, recorded during a semantic classification task. Participants were healthy patients whose obsessive-compulsive tendencies were assessed using a questionnaire. In this task, when presented with a red colored word, participants were required to classify it into categories as either plants or animals with a keypress (i.e. the classification condition). When presented with a green colored word, participants were required to read it without classification (i.e. the inhibition condition). The behavioral results showed that the semantic negative priming (i.e. the increase in reaction time to the word included in the previously inhibited category) was negatively correlated with obsessive-compulsive tendencies. Electroencephalograph results showed that the left frontal-motor alpha phase synchronization under the classification condition was significantly higher than under the inhibition condition. This phase synchronization under the inhibition condition was positively correlated with obsessive-compulsive tendencies. These results suggest that a dynamic link between the left frontal and motor areas may reflect reduced semantic inhibition in individuals with stronger obsessive-compulsive tendencies.

Contributions of non-primary cortical sources to auditory temporal processing

Temporal processing is essential for speech perception and directional hearing. However, the number and locations of cortical sources involved in auditory temporal processing are still a matter of debate. Using source reconstruction of human EEG responses, we show that, in addition to primary sources in the auditory cortices, sources outside the auditory cortex, designated as non-primary sources, are involved in auditory temporal processing. Non-primary sources within the left and right motor areas, the superior parietal lobe and the right occipital lobe were activated by amplitude-modulated stimuli, and were involved in the functional network. The robustness of these findings was checked for different stimulation conditions. The non-primary sources showed weaker phase-locking and lower activity than primary sources. These findings suggest that the non-primary sources belong to the non-primary auditory pathway. This pathway and non-primary sources detected in motor area explain how, in temporal prediction of upcoming stimuli and motor theory of speech perception, the motor area receives auditory inputs.

Sleep Quality, Depression, and Quality of Life After Bilateral Anodal Transcranial Direct Current Stimulation in Patients with Parkinson's Disease.

BackgroundSleep dysfunctions impose a large burden on quality of life for patients with Parkinson’s disease (PD). Several studies on PD reported potential therapeutic effects of transcranial direct current stimulation (tDCS) on motor and non-motor functions, but not related to sleep quality. Therefore, the present study examined sleep quality, depression perception, and quality of life changes after bilateral anodal tDCS in patients with PD.Material/MethodsTwenty-one patients (n=21) with PD underwent 10 sessions (20 min each, 5 per week) of bilateral anodal tDCS stimulation applied simultaneously over the left and right prefrontal and motor areas. The Pittsburgh Sleep Quality Index (PSQI) total score and sub-scores, Geriatric Depression Scale (GDS), and Health-related quality of life questionnaire (SF-36) were measured pre/post bilateral tDCS anodal stimulation.ResultsPSQI total score (P=0.045), sleep latency sub-score (P=0.02), and GDS total score (P=0.016) significantly decreased, and physical and mental components scores of SF-36 (P=0.018 and P=0.001, respectively) significantly increased after bilateral anodal tDCS stimulation. The GDS score decrease was directly correlated with decrease in PSQI total score (P=0.01), sleep latency sub-score (P=0.002), and sleep disturbance sub-score (P=0.003). In addition, the GDS score decrease was inversely correlated with increasing mental component score of SF-36 (P=0.001), which was directly correlated with an increase in sleep efficiency sub-score (P=0.03) and the physical component score of SF-36 (P=0.0001).ConclusionsBilateral anodal tDCS stimulation showed potential therapeutic effects in patients with PD in terms of sleep quality and depression level improvement, which together improved mental and physical quality of life in patients with PD.

Cathodal tDCS on the motor area decreases the tactile threshold of the distal pulp of the hallux

Transcranial direct current stimulation (tDCS) has been reported to modulate cortical excitability. Most studies on this topic addressed the modulation effects of tDCS on the upper extremities. Foot-sole tactile sensation is essential to gait, but little is known about the effect of tDCS on sensory function in the foot area. Here we administered tDCS to 10 healthy adults, and we observed that the modulation effects of cathodal tDCS on the left motor area led to a decrease in the tactile threshold of the left center of the distal pulp of the hallux. This effect was not observed in the sham condition. In addition, the subjects' vigilance levels were not changed between before and after the tDCS. These results suggest that sensation on the sole of the left foot could be modulated by cathodal tDCS on the left motor area.

Thinking about the past to shape the present: neural activation during the recall of relationship episodes

Reflecting on oneself and others in relationships is an ability that is central to our social existence. Specifically, considering formative autobiographical experiences in relationships may contribute to more flexibility in perceiving, as well as in shaping present relationships. Reflecting on such experiences mobilizes different social cognitive and affective processes. We aim to explore the neural basis of these processes. With a newly developed functional magnetic imaging (fMRI) task, we investigated brain activation in 35 healthy individuals during recall of relationship episodes involving themselves or others. We found that recalling formative episodes involving themselves modulated brain activity in the right parahippocampus, left precuneus, bilateral fusiform gyrus, bilateral insula, and left presupplementary motor area. These areas are involved in memory processes, self-generated thought, and affective experience. The recall of relationship episodes involving others led to similar activation patterns. Our results underscore the close link between self-reflection, understanding others, and memory processes and emphasize the role of affective dimensions for self-relevant experiences. They contribute to a growing body of research on neural mechanisms involved in complex social cognitive processes decisive for our capacity to navigate our social environment.

Sensory-motor synchronization in the brain corresponds to behavioral synchronization between individuals

Behavioral rhythms between individuals are known to spontaneously synchronize through social interactions; however, it remains unclear whether inter-brain synchronization emerges with this behavioral synchronization in the case of anti-phase coordination with other's behavior (e.g. turn-taking). In this study, we simultaneously recorded electroencephalograms (EEGs) we simultaneously recorded electroencephalograms (EEGs) from 2 participants as 1 pair (in total, 34 right-handed participants as 17 pairs) during an alternate tapping task in which pairs of participants alternated tapping a key with their right finger. Participants sat facing computer displays and were asked to match their partners’ tapping intervals using visual feedback that was presented on the displays. Based on their ability to synchronize, we divided participants into Good performance and Poor performance groups. In both groups, wavelet analyses of EEG data revealed alpha-(approximately 12 Hz) and beta-(approximately 20 Hz) amplitude modulation in the left motor areas. Interestingly, both alpha and beta amplitudes were correlated between individuals from the Good group, but not from the Poor group. Moreover, while the Good group showed intra-brain and inter-brain alpha-phase synchronization (about 12 Hz) within the posterior brain areas (i.e., visual areas) and the central brain areas (i.e., motor areas), the Poor group did not. These results suggest that inter-brain synchronization may play an important role in coordinating one's behavioral rhythms with those of others.

Cortical phase locking to accelerated speech in blind and sighted listeners prior to and after training

Cross-correlation of magnetoencephalography (MEG) with time courses derived from the speech signal has shown differences in phase-locking between blind subjects able to comprehend accelerated speech and sighted controls. The present training study contributes to disentangle the effects of blindness and training. Both subject groups (baseline: n = 16 blind, 13 sighted; trained: 10 blind, 3 sighted) were able to enhance speech comprehension up to ca. 18 syllables per second. MEG responses phase-locked to syllable onsets were captured in five pre-defined source locations comprising left and right auditory cortex (A1), right visual cortex (V1), left inferior frontal gyrus (IFG) and left pre-supplementary motor area. Phase locking in A1 was consistently increased while V1 showed opposite training effects in blind and sighted subjects. Also the IFG showed some group differences indicating enhanced top-down strategies in sighted subjects while blind subjects may have a more fine-grained bottom-up resolution for accelerated speech.

Aberrant cerebro-cerebellar functional connectivity and minimal self-disturbance in individuals at ultra-high risk for psychosis and with first-episode schizophrenia

BackgroundIn the tradition of phenomenology, minimal selfdisturbance has been suggested as a manifestation of the core pathogenesis of schizophrenia; however, the underlying neural mechanism remains unclear. Here, in line with the concept of “cognitive dysmetria,” we investigated the cerebro-cerebellar default mode network (DMN) connectivity and its association with pre-reflective minimal selfdisturbance in individuals at ultra-high risk (UHR) for psychosis and patients with first-episode schizophrenia (FES). MethodsThirty-three UHR individuals, 18 FES patients, and 56 healthy controls (HCs) underwent functional magnetic resonance imaging during rest at baseline. Seed-based functional connectivity (FC) analysis was performed using the cerebellar DMN seeds from the bilateral Crus I, followed by between-group comparisons. Correlation analysis was conducted to examine the relationship between the cerebro-cerebellar FC and the self-reported severity of minimal self-disturbance in the UHR and FES groups, respectively. ResultsFES participants showed significantly reduced cerebellar FC with the left presupplementary motor area (preSMA), right anterior prefrontal cortex (aPFC), and precuneus compared to HCs, while UHR participants showed an intermediate decrease between the other two groups, particularly in the left preSMA and right aPFC. Minimal self-disturbance, which appeared at similar levels in both UHR and FES groups, was significantly associated with cerebro-cerebellar FC, although each group presented different patterns of associations. ConclusionsAberrant cerebro-cerebellar FC, which may be closely related to minimal self-disturbance, may be able to provide meaningful insights into the real gestalt of schizophrenia and contribute to further research to predict future psychosis in UHR individuals.

A double dissociation between two psychotic phenotypes: Periodic catatonia and cataphasia

Schizophrenia as a single liability model was confronted to the multiple psychotic phenotypes model proposed by the Wernicke-Kleist-Leonhard school, focusing on two: periodic catatonia (PC) and cataphasia (C). Both are stable and heritable psychotic phenotypes with no crossed liability and are coming with the buildup of specific residual symptoms: impairment of psychomotricity for PC and a specific disorganization of thought and language in C. Regional cerebral blood flow (rCBF) was used as a biomarker. We attempted to refute the single phenotype model by looking at relevant and specific rCBF anomalies for PC and C, that would exceed anomalies in common relative to controls (CTR), i.e. looking for a double dissociation. Twenty subjects with PC, 9 subjects with C and 27 matched controls had two MRI QUIPSS-II arterial spin labeling sequences converted in rCBF. One SPM analysis was performed for each rCBF measurement and the results were given as the conjunction of both analysis. There was a clear double dissociation of rCBF correlates between PC and C, both being meaningful relative to their residual symptomatology. In PC: rCBF was increased in the left motor and premotor areas. In C: rCBF was decreased bilaterally in the temporo-parietal junctions. Conversely, in both (schizophrenia): rCBF was increased in the left striatum which is known to be an anti-psychotics' effect. This evidence refuts the single schizophrenia model and suggests better natural foundations for PC and C phenotypes. This pleads for further research on them and further research on naturally founded psychotic phenotypes. Clinical trialName of the registry: ClinicalTrials.govIdentification: NCT02868879

More far is more right: Manual and ocular line bisections, but not the Judd illusion, depend on radial space

Line bisection studies generally find a left-to-right shift in bisection bias with increasing distance between the observer and the target line, which may be explained by hemispheric differences in the processing of proximo-distal information. In the present study, the segregation between near and far space was further characterized across the motor system and contextual cues. To this aim, 20 right-handed participants were required to perform a manual bisection task of simple lines presented at three different distances (60, 90, 120 cm). Importantly, the horizontal spatial location of the line was manipulated along with the viewing distance to investigate more deeply the hemispheric engagement in the transition from near to far space. As the motoric component of the manual task producing activations of left premotor and motor areas may be partially responsible for the observed transition, participants were also involved in an ocular bisection task. Further, participants were required to bisect Judd variants of the target lines, which are known to elicit a Müller-Lyer-type illusion. Since the Judd illusion depends on areas in the ventral visual stream, we predicted that line bisections of Judd-type lines would be unaffected by viewing distance. Results showed that manual bisection of simple lines was modulated separately by viewing distance and the hemispace of presentation, with this pattern being similar for ocular bisection. Critically, bisections in the Judd illusion task were not modulated by viewing distance, whether performed by hand or by eye. Overall, these findings support the hypothesis that the right hemisphere plays a dominant role in the processing of space close to the body. They also present novel evidence for a general reduction of this dominance at farther distances, whether hand motor actions are involved or not. Finally, our study documents a dissociation between the processing of pure visuospatial information and that of a visual illusion as a function of viewing distance, supporting more generally the dorsal/near space and the ventral/far space segregation.

Timing of cortical activation during spontaneous swallowing.

Saliva accumulation in the oropharynx generates an automatic pattern of swallowing in the brainstem in animals. Previous fMRI studies have found that spontaneous saliva and water swallows in humans evoked activation following swallow onset in both precentral motor and postcentral somatosensory cortical regions. Using event-related averaging of continuous functional near infrared spectroscopy (fNIRS), we examined cortical hemodynamic responses (HDR) from 5s before to 35s after spontaneous reflexive saliva swallow onset in the lateral postcentral somatosensory and precentral motor regions in both hemispheres in healthy volunteers. Three HDR changes from baseline were detected. First, the onset of HDR occurred 2s before swallow onset in the left postcentral somatosensory area and 0.67s before swallow onset in the right postcentral somatosensory area. Second, an early HDR peak amplitude occurred 3-4s after swallow onset in all four regions. Z scores relative to baseline pre-swallow cortical activity levels averaged 20 and 22.7s in the right and left somatosensory regions and 10 and 15.8s in left and right motor areas, respectively. Finally, a late HDR peak occurring between 22 and 23s after swallow onset in the somatosensory regions and 17-19s in the motor areas likely resulted from esophageal peristalsis. Overall, cortical activation timing relative to swallow onsets showed activation began before the pharyngeal phase of swallowing in the somatosensory areas. This indicates that somatosensory triggering of swallowing occurs not only in the brainstem but also in the cortex for reflexive saliva swallowing in awake humans.

Methylphenidate alters brain connectivity after enhanced physical performance

Muscle fatigue is a disturbed homeostatic state characterized by a temporary inability to maintain force output and has lasting effects on the brain in the period immediately after exercise, such as decreased interhemispheric functional connectivity (FC). Stimulants that increase dopamine and norepinephrine neurotransmission can enhance performance during muscle fatiguing exercise (i.e. are ergogenic). We recently demonstrated that methylphenidate (MPH) increased force output and increased FC between the insular (IC) and hand motor cortex during a fatiguing handgrip task. However, whether resting FC is altered in the recovery period after enhanced force is unknown. The objective of these follow-up analyses was to examine the effects of performing a fatiguing handgrip task with MPH on subsequent resting state FC. In a double-blind counter-balanced design, participants ingested placebo or MPH and in a magnetic resonance imaging scanner performed: a six-minute pre-task resting scan, a fatiguing handgrip task during scanning, and then a six-minute post-task resting scan. We investigated task-related force and resting state FC pre- and post-task between: (1) interhemispheric motor cortices (M1) and (2) the right IC and left hand motor area. We found 1) a post-task reduction in M1 interhemispheric FC and that the extent of reduciton was negatively correlated with enhanced mean trial force in MPH conditions. 2) MPH but not placebo increased post-task FC between the right IC and left hand motor area. This study demonstrates that using MPH during a muscle fatiguing task has lasting effects on the brain that are markedly different from drug naïve conditions.

Effect of Social Stress on Motor Function in Older Adults: an fNIRS Investigation

Stress has adverse impacts on mental and physical health and quality of life, especially in older adults. Stress can impair cognitive function including short and long-term memory, and this functional declines can further be associated with decreased neuromuscular performance (Mehta & Parasuraman, 2014) and increased fatigability (Keller-Ross et al., 2014). Since older adults are more susceptible to the effect of stress because their limited mobility caused by aging can worsen under stress (Noven at al., 2014), it is important to examine the effect of acute stress on neuromuscular function in older adults. In the present study, we tested the effect of social stress on neuromuscular function of both upper and lower extremity in older adults before and after a short bout of social stress. Thirty participants (15 males, 15 females, mean age: 73.3 (5.6) yrs) performed ten trials of submaximal voluntary contraction at 30% of their maximum voluntary contraction force level before and after the Trier Social Stress Test (TSST) session. Handgrip and knee extension motor performance was measured on separate days. TSST consisted of five minutes speech and five minutes serial arithmetic subtraction tasks. We measured force steadiness and electromyography (EMG) of working muscles to evaluate motor function. Additionally, electrocardiogram (ECG), the Visual Analogue Scale of Stress (VAS), and salivary cortisol were collected to evaluate the effect of the TSST. Neural activation pattern changes of prefrontal and sensorimotor area during exercise and TSST sessions was recorded using functional Near Infrared Spectroscopy (fNIRS). To confirm whether the TSST session increased stress level in our participants, we first analysed the stress metrics. Heart rate increased during the TSST and returned to prestress level instantly after the TSST session. Perceived stress level using the VAS increased after TSST. While not significant, salivary cortisol level increased after the TSST session. Findings indicate that handgrip force steadiness improved after the TSST session, whereas knee extension force steadiness remained unchanged. On the other hand, handgrip EMG root mean square (RMS) did not change after stress while knee extension EMG RMS was found to increase. Neural activation during handgrip exercise increased at the left motor area, and neural activation during knee extension increased at the left sensory area after the TSST session. Change of heart rate and VAS indicates that participants’ stress level was increased after stress and the improved motor performance during handgrip exercise after the stress is consistent with a previous study that reported increased memory function after stress in older adults (Pulopulos et al., 2015). However, the differential effects of stress based on upper or lower extremity indicates increased sensitivity of certain motor tasks to social stress than other. While social stress is known to affect response time but not memory function (Guez et al., 2016), different spatial activation pattern between handgrip and knee extension exercises observed in the present study suggest that different neural strategies were adapted to compensate for the effects of acute social stress to maintain motor performance.

Cathodal tDCS evidence on how perceived body weight similarity and weight stigma can modulate the understanding of observed familiar actions

Previous experimental evidence has shown that motor resonance (i.e. the mapping of others’ actions onto one’s own motor repertoire) can be influenced by individual differences in personality traits. However, no evidence has been reported so far of the effects of physical appearance and negative attitudes toward obesity to the mechanism of MR. In the present study, normal-weight and overweight participants performed an implicit task, in which they were observing amateur actors reaching and grasping a light or heavy cube with or without deception (true vs. fake actions). Physical similarity between observers and actors was manipulated by presenting videos of slim or overweight actors. Before the task, all participants received cathodal or sham transcranial direct current stimulation (tDCS) over the left motor cortex, previously shown to decrease excitability of the aforementioned cortical area. At the end of each video-clip participants were instructed to indicate the correct cube size (light or heavy). Fat phobic attitudes and automatic preference for thin than fat people were also examined. Signal detection analysis (d’) on the currently acquired accuracy data (N=15) has indicated a significant 3-way interaction between type of stimulation (cathodal, sham), type of action (true, fake) and model weight. Overall, both normal and overweight participants were able to better simulate the actions performed by the slim as compared to overweight actors. However, this effect was diminished after cathodal stimulation of the left hemisphere motor area. Hence, we provide experimental evidence of action simulation and understanding being modulated by an implicit preference towards slim bodies.

Atypical activation of action-semantic network in adolescents with autism spectrum disorder

In typical adults, fMRI studies have shown activation of primary and pre-motor regions during action word processing. Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by social and communication impairments. ASD studies have shown atypical semantic processing and motor deficits. The objective of this study was to examine semantic processing of verbs in ASD. 15 ASD adolescents and 19 typically developing adolescents, 11–16years, completed a semantic similarity judgment task during fMRI. There were no differences in task accuracy or reaction time. At the group level, both groups had activation in left language areas; controls, but not ASD, also had activation in the left pre-supplementary motor area (pre-SMA). In ASD, less left frontal activation and reduced left lateralization of activation within these regions was associated with shorter reaction times and better language skills. More left temporal activation was associated with better language abilities in ASD. Differences in pre-SMA activation may relate to motor planning deficits or differences in approach to the semantic task in ASD. Results suggest that left frontal language areas may be less efficient in ASD and those who can compensate by recruiting more right hemisphere homologues may result in better language abilities.

Increased arithmetic complexity is associated with domain-general but not domain-specific magnitude processing in children: A simultaneous fNIRS-EEG study.

The investigation of the neural underpinnings of increased arithmetic complexity in children is essential for developing educational and therapeutic approaches and might provide novel measures to assess the effects of interventions. Although a few studies in adults and children have revealed the activation of bilateral brain regions during more complex calculations, little is known about children. We investigated 24 children undergoing one-digit and two-digit multiplication tasks while simultaneously recording functional near-infrared spectroscopy (fNIRS) and electroencephalography (EEG) data. FNIRS data indicated that one-digit multiplication was associated with brain activity in the left superior parietal lobule (SPL) and intraparietal sulcus (IPS) extending to the left motor area, and two-digit multiplication was associated with activity in bilateral SPL, IPS, middle frontal gyrus (MFG), left inferior parietal lobule (IPL), and motor areas. Oscillatory EEG data indicated theta increase and alpha decrease in parieto-occipital sites for both one-digit and two-digit multiplication. The contrast of two-digit versus one-digit multiplication yielded greater activity in right MFG and greater theta increase in frontocentral sites. Activation in frontal areas and theta band data jointly indicate additional domain-general cognitive control and working memory demands for heightened arithmetic complexity in children. The similarity in parietal activation between conditions suggests that children rely on domain-specific magnitude processing not only for two-digit but-in contrast to adults-also for one-digit multiplication problem solving. We conclude that in children, increased arithmetic complexity tested in an ecologically valid setting is associated with domain-general processes but not with alteration of domain-specific magnitude processing.

P235 Variation during the day of the TMS-EEG evoked potential

Introduction When applying concurrent TMS-EEG, a characteristic waveform – the TMS evoked potential (TEP) – can be measured. The amplitude of an early TEP component (∼20 ms) increased with time awake in healthy subjects ( Huber et al., 2012 ), and long intracortical inhibition (LICI) decreased ( Lang et al., 2011 ), both suggesting an increase in excitability during the day. Excitability was found to be higher in the morning compared to the evening in generalized epilepsy patients ( Badawy et al., 2009 ). For TMS to be of clinical diagnostic use, these diurnal changes should be smaller than the difference in response between epilepsy patients and controls. We studied the influence of the time of day on the overall TEP in healthy controls, using five sessions on one day. Objectives To study the variation of the TEP during the day when stimulating the motor and visual cortex. Subjects and methods TMS-EEG was recorded in 15 healthy subjects using a Magstim Rapid2 stimulator and a 64-channel EEG amplifier (ANT Neuro, Enschede). TMS was targeted at four brain regions: left and right motor cortex (MC), and left and right Brodmann area 19 (B19). At each target, we administered 75 pulses at an intensity of 110% resting motor threshold. Subjects were stimulated during five sessions in one day (8:00 AM, 10:30 AM, 13:00 PM, 15:30 PM and 18:00 PM) while keeping the stimulation intensity constant. Trials were averaged to obtain the TEP. We compared the TEP waveforms between the five sessions with a cluster-based permutation analysis using a dependent t-test and correcting for multiple comparisons (Bonferroni). Results TEPs with components N15, P30, N45, P60, N100 and P180 were present in all subjects after stimulating the MC. The TEP after B19 stimulation consisted of the components N5, P25, N40, P50, N75, P120, N160 and P200. There were no significant differences between the five sessions for both MC and B19 stimulation. Conclusion The TEP is highly reproducible during the day. We found no significant variation of the overall TEP between multiple sessions on one day.

P070 Therapeutic possibilities of repetitive magnetic stimulation at patients with various neurological disorders

Introduction Repetitive transcranial magnetic stimulation (rTMS) is a promising method in treatment of patients with various neurological diseases not only transcranially, but also at other levels of the nervous system, including peripheral. Currently, there are different protocols for the treatment of patients with neurological disorders at the lumbar level, for the treatment of headache, central pain syndromes and other neurogenic disorders. Objective Goal of this pilot study was to update and adapt existing protocols of rTMS for neurological patients. Methods Therapeutical magnetic stimulation was performed in order to restore lost function or for pain relief between the two groups of observations: patients with the development of compression syndromes in the lumbar level (12 patients) and chronic headache (7 patients) and in two patients with tremor-rigid form of Parkinson’s disease. To avoid terminological confusion, the abbreviation “rTMS” in this paper is applied on the second group of patients and patients with Parkinson’s disease; for the first group, the term “rTMS” is replaced by the already adopted in the literature “rPMS” – rhythmic peripheral magnetic stimulation. After studying international experience (Le Faucheur JP et al. Evidence-based guidelines on the therapeutic use of repetitive transcranial magnetic stimulation (rTMS). Clin Neurophysiol 2014), for the first group of patients, it was decided to carry out a rhythmic low frequency stimulation of the lumbosacral (L3-S1) region, in the projection of the nerve structures, which caused motor deficit, sensory disorders, urinary retention. In the second group was used low (less than 5 Hz) and high (5–15 Hz) frequency rTMS at the nape area and left premotor area, respectively. Patients with Parkinson’s disease carried out high-frequency (8–12 Hz) RTMS to the left and right motor areas of the cerebral cortex (M1). For magnetic stimulation device was used MagPro X100 (“Medtronic”, USA) equipped with a circular coil (mcf-125), in combination with neurosensory analyzer “Viking IV” of “Nicolet” (USA) as a diagnostic system. Stimulation was carried at rates of 5–15 sessions lasting 15–35 min, 1 time per day. Results In the first group of patients after rTMS course most of them (8 of 12) subjectively noted relief of the pain syndrome. In more than 60% of cases the effect was persistent: 1.5 months after stimulation. In the second group of patients it was shown that only low-frequency rTMS of cervical-occipital region was ineffective – for 5 sessions, there was no evidence of any significant changes in patient’s status. The positive effect of reducing the intensity and duration of the headaches was noticed only after joining the high-frequency stimulation of the left premotor area (approximately after 8 sessions), which grew progressively by the end of therapy. During dynamic monitoring of patients with Parkinson’s disease positive changes in the motor functions were manifested by about 6–9 magnetic stimulation procedures (increase in muscle strength in the limbs, improvement of the accuracy of movements and improvement of fine motor skills). Thus, these results suggest a promising therapeutic application of rhythmical MS for patients in all represented groups, but verification and refinement of the effects on a larger sample of observations are required. Supported by grant RFBR # 15–29-08304.

Implicit Learning of a Finger Motor Sequence by Patients with Cerebral Palsy After Neurofeedback.

Facilitation of implicit learning of a hand motor sequence after a single session of neurofeedback training of alpha power recorded from the motor cortex has been shown in healthy individuals (Ros et al., Biological Psychology 95:54-58, 2014). This facilitation effect could be potentially applied to improve the outcome of rehabilitation in patients with impaired hand motor function. In the current study a group of ten patients diagnosed with cerebral palsy trained reduction of alpha power derived from brain activity recorded from right and left motor areas. Training was distributed in three periods of 8min each. In between, participants performed a serial reaction time task with their non-dominant hand, to a total of five runs. A similar procedure was repeated a week or more later but this time training was based on simulated brain activity. Reaction times pooled across participants decreased on each successive run faster after neurofeedback training than after the simulation training. Also recorded were two 3-min baseline conditions, once with the eyes open, another with the eyes closed, at the beginning and end of the experimental session. No significant changes in alpha power with neurofeedback or with simulation training were obtained and no correlation with the reductions in reaction time could be established. Contributions for this are discussed.