Mobile EEG Research Articles

Spectral modulation of frontal EEG during motor skill acquisition: A mobile EEG study

This study investigates the modulation of frontal EEG dynamics with respect to progress in motor skill acquisition using a wireless EEG system with a single dry sensor. Participants were required to complete repeated trials of a computerized visual-motor task similar to mirror drawing while the EEG was collected. In each trial, task performance of the participants was summarized with a familiarity index which took into account the performance accuracy, completion rate and time. Our findings demonstrated that certain EEG power spectra decreased with an increase in motor task familiarity. In particular, frontal EEG activities in delta and theta bands of the whole trial and in gamma band in the middle of the trial are having a significant negative relationship with the overall familiarity level of the task. The findings suggest that frontal EEG spectra are significantly modulated during motor skill acquisition. Results of this study shed light on the possibility of simultaneous monitoring of brain activity during an unconstrained natural task with a single dry sensor mobile EEG in an everyday environment.

Mobile EEG in epilepsy

The sensitivity of routine EEG recordings for interictal epileptiform discharges in epilepsy is limited. In some patients, inpatient video-EEG may be performed to increase the likelihood of finding abnormalities. Although many agree that home EEG recordings may provide a cost-effective alternative to these recordings, their use is still not introduced everywhere. We surveyed Dutch neurologists and patients and evaluated a novel mobile EEG device (Mobita, TMSi). Key specifications were compared with three other current mobile EEG devices. We shortly discuss algorithms to assist in the review process. Thirty percent (33 out of 109) of Dutch neurologists reported that home EEG recordings are used in their hospital. The majority of neurologists think that mobile EEG can have additional value in investigation of unclear paroxysms, but not in the initial diagnosis after a first seizure. Poor electrode contacts and signal quality, limited recording time and absence of software for reliable and effective assistance in the interpretation of EEGs have been important constraints for usage, but in recent devices discussed here, many of these problems have been solved. The majority of our patients were satisfied with the home EEG procedure and did not think that our EEG device was uncomfortable to wear, but they did feel uneasy wearing it in public.

Improving Driver Alertness through Music Selection Using a Mobile EEG to Detect Brainwaves

Driving safety has become a global topic of discussion with the recent development of the Smart Car concept. Many of the current car safety monitoring systems are based on image discrimination techniques, such as sensing the vehicle drifting from the main road, or changes in the driver's facial expressions. However, these techniques are either too simplistic or have a low success rate as image processing is easily affected by external factors, such as weather and illumination. We developed a drowsiness detection mechanism based on an electroencephalogram (EEG) reading collected from the driver with an off-the-shelf mobile sensor. This sensor employs wireless transmission technology and is suitable for wear by the driver of a vehicle. The following classification techniques were incorporated: Artificial Neural Networks, Support Vector Machine, and k Nearest Neighbor. These classifiers were integrated with integration functions after a genetic algorithm was first used to adjust the weighting for each classifier in the integration function. In addition, since past studies have shown effects of music on a person's state-of-mind, we propose a personalized music recommendation mechanism as a part of our system. Through the in-car stereo system, this music recommendation mechanism can help prevent a driver from becoming drowsy due to monotonous road conditions. Experimental results demonstrate the effectiveness of our proposed drowsiness detection method to determine a driver's state of mind, and the music recommendation system is therefore able to reduce drowsiness.

The urban brain: analysing outdoor physical activity with mobile EEG

BackgroundResearchers in environmental psychology, health studies and urban design are interested in the relationship between the environment, behaviour settings and emotions. In particular, happiness, or the presence of positive emotional...

ID Proof on the Go: Development of a Mobile EEG-Based Biometric Authentication System

In recent years, the need for greater security for storing personal and business data or accessing corporate networks on mobile devices has been growing rapidly, and one of the potential solutions is to employ innovative biometric authentication techniques. This article presents the development of a mobile biometric authentication system based on electroencephalogram (EEG) recordings in combination with already proven technologies such as facial detection and nearfield communication (NFC). The overall goal of this work is to fill the gap between mobile Web technologies and wireless EEG devices and to develop a new authentication technique and a feasible application. Therefore, we review the relevant literature, conduct several EEG measurement experiments, and discuss the procedure and results with experts in the EEG and digital signal processing (DSP) fields. On the basis of these results, we build and present a mobile prototype system capable of authenticating users based on the uniqueness of their brain waves. Furthermore, we implement a novel authentication process that will make the authentication system more secure. We also give suggestions for future improvements to the system.

2509 簡易的脳波計による無線ロボット操作時における方向入力手法の提案

2509 簡易的脳波計による無線ロボット操作時における方向入力手法の提案

An Ethno‐Methodological Approach to Cannabis and Music Perception, with EEG Brain Mapping in a Naturalistic Setting

Cannabis is known to change auditory perception and music appreciation as many musicians and music listeners report in narratives, interviews and biographies. An ethnographic pre/post study was conducted in a habituated naturalistic setting, combining qualitative and quantitative methods with four single case studies. Physiological results were gained with a mobile bedside EEG imaging machine in an authentic setting of the consumer's life‐world. Results represent explorative data of participants' spontaneous EEG‐activity, referable to results of psychological and medical studies.Increasing Alpha‐signal strength in parietal association cortex and significant Theta band changes in temporal and on Alpha in occipital areas seem to represent an intraindividual constant EEG correlate of temporarily intensified attention ("high"), resulting in an altered music perception by hyperfocusing on acoustic space and broadened insight into the "space between the notes." THC has a measurable influence on cerebral music processing and seems to enhance acoustic perception temporarily.

EEG-Pen for medical emergencies.

This paper deals with a handy, mobile emergency EEG device. It provides a direct and immediate access to patients brain activity. This EEG-Pen consists of spring-loaded electrodes and all necessary components. Current mobile EEG systems do not seem to be appropriate for emergencies since they require a lot of time-consuming preliminary work. Usually the skin has to be pre-treated, the electrodes and the wires have to be attached to the body. This prototype of an EEG-Pen would do away with such preliminary measures and therefore becomes an essential tool for emergencies. Good recordings have been obtained. A miniaturized EEG-Pen, which can be easily carried by physicians or medical staff and immediately be used as a "bioelectric signal detector", requires more research.

Cytokine production during sleep and wakefulness and its relationship to cortisol in healthy humans.

A growing body of evidence indicates that cytokines, especially interleukin-1 beta, are involved in the regulation of sleep and wakefulness. The aim of the present pilot study was to investigate the relationship between interleukin-1 beta (IL-1 beta) and gamma-interferon (gamma-IFN) production and the regulation of sleep and wakefulness. Four healthy male volunteers were investigated. After one adaptation night, beginning at 8 a.m. in the morning, the EEG was recorded by means of a mobile long-term EEG and blood samples were drawn every 45 min for the analysis of IL-1 beta, gamma-IFN and cortisol for 24 h. For the analysis of cytokines whole blood cultures were established. After 48 h of incubation in the presence of endotoxin Salmonella typhimurium, IL-1 beta and gamma-IFN levels were measured in the culture supernatants using specific immunodetection assays. Methods of stochastic time series analysis were adopted to evaluate the biochemical data. Our results show the capability of cultured blood cells to produce cytokines upon endotoxin challenge to be at a maximum around the time of sleep onset and during the first hours of sleep, declining during the night to a minimum level in the morning hours. The opposite was observed for cortisol. The analysis of autocorrelation functions gives evidence of a 24-hour rhythm of cortisol and cytokines. The results indicate that the cytokines IL-1 beta and gamma-IFN may play a role in sleep regulation.

Day by day variations of the amount of spike-wave activity in 24 hour cassette recordings

For interpretation of mobile long-term EEG monitoring in patients suffering from absence epilepsies with regular spike-wave (S-W) paroxysms, the fluctuating amount of this parameter has to be taken into account if, for example, therapeutic effects are to be judged. An ‘S-W variogram’ is derived resembling the statistical properties of the day by day variability as an orienting criterion in this respect.

Mobile long-term EEG monitoring in generalized seizure disorders of different etiology.

Eighteen EEG long-term recordings were carried out in patients with generalized fits of different etiologies using a mobile 4-channel monitoring system in order to observe individual patterns of epileptic activity. In patients with idiopathic tonic-clonic seizures (A) no connection of frequency of spike-wave bursts with the sleep-wakefulness cycle was observed. In patients suffering from fits of organic nature (B) a peak of paroxysms was obtained in the hours before sleep onset, whereas in patients with absence seizures (C) a maximum was found in the morning hours after awakening. In patients with idiopathic fits (tonic-clonic and absence seizures) the minimum of bursts was observed in REM sleep, whereas stage 0 (tonic-clonic) and stage 1 (absence) were most prone to discharges. Patients with secondary generalized epilepsy had most spike-wave bursts in deep sleep. In the absence seizure group the transitional periods within the light non-REM-sleep stages were more susceptible to paroxysms than the retained stages. In patients with idiopathic grand mal seizures, the highest frequency of paroxysmal discharges was found during time spent awake in the night when retained over a longer period of time. The group including cases with attacks of organic nature did not show any preference to shifting times or preservation episodes of sleep stages.

Epileptic activity during sleep and wakefulness.

In 23 untreated patients the temporal distribution of generalized spike-wave activity was investigated by means of mobile long-term EEG recordings. Distribution classes (S, A, W) were defined if the relative amount of epileptic activity within the phases sleep, awakening and waking exceeded a threshold, otherwise a diffuse distribution (D) was scored. A, S and D distributions were found approximately with the same frequency. In no patient was the middle part of the night most prominent. In one patient, it was shown by micro-hypnograms that 'micro-arousals' are closely related to spike-wave activity.

Computerized analysis of epileptic activity and sleep in mobile long-term EEG monitoring.

Implemented on a LSI 11/73 microcomputer, an approach is presented to perform pattern recognition of one channel in high speed (factor 20). A mimetic algorithm, acting in time domain, continuously tests the signal with respect to the occurrence of spike-wave-like patterns and calculates a low frequency index describing the time of sleep. Those epochs suspected of containing paroxysmal activity are stored on disk for subsequent editing. In a similar way, 8-channel analysis is possible if the replay speed is less than 20 times real time.

Sleep-Inducing Effect of <i>L</i>-Tryptophane

Night sleep recordings were performed in 10 patients with sleep disturbance in falling asleep as well as in maintaining sleep using a mobile 4-channel EEG registration system. Three consecutive nights, which were spent under different conditions, were evaluated automatically. The first night without treatment was used as a baseline night to objectify the disturbed sleep, the second night was measured following an infusion of a physiological saline solution and prior to the third recording 5 g l-tryptophane were applied to the patients. Besides a significant decrease of delayed latency times until the appearance of the light sleep stages, an influence was seen on the quantitative sleep parameters such as sleep period time and total sleep time. In parallel, an improvement of the subjective feeling measured by a self-rating scale resulted after l-tryptophane. On the other hand, no definite influence on the other sleep parameters such as an increase of slow wave sleep was observed, so that the use of this treatment might be recommended in disturbances in falling asleep particularly.

Sleep alterations in ischemic stroke.

In 19 patients with cerebral infarctions in the middle cerebral artery territory, investigations of sleep using a mobile EEG recording system were performed. Sleep was found to be markedly altered compared to a normal group. Although an increase of time in bed and sleep period time was observed, total sleep time did not rise in a parallel manner, so that a distinct reduction of the sleep efficiency index was found. This increase of quantitative parameters was particularly caused by a higher amount of NREM time, whereas REM sleep was found to be deeply suppressed. Regarding the different NREM sleep stages, stage 0 (time spent awake during the night) and stage 1 had increased, whereas stage 4 was reduced. Interhemispheric differences were noticed referring to the sleep period time, which was found to be increased particularly in right-sided infarctions (because of an increase of NREM time) and a reduction of REM sleep in lesions of the right hemisphere (worsening of the REM to NREM ratio). Slow-wave sleep (stage 4), on the contrary, was found to be decreased in infarctions of the left hemisphere. These results support the hypothesis of a REM-inducing and regulating function of the right hemisphere and will lead to a new understanding of sleep-controlling mechanisms.

Die EEG-Langzeitregistrierung im Vergleich zum Schlafentzug und anderen Provokationsmethoden bei Epilepsiepatienten

37 epileptics with routine records without paroxysms were subject to 24 hours mobile long-term EEG registration and independently 24 hours sleep deprivation EEG including hyperventilation and photic stimulation. The anticonvulsive treatment was not changed. In 14 cases we could prove epileptiform discharges (= positive finding) by using both methods, in 13 after sleep derivation (10 at rest, 3 only during hyperventilation) in 7 in the long-term record and in 6 of them both after sleep deprivation and in long-term record. As epileptiform discharges we rated spikes, spikes ans slow waves, epileptic K-complexes, spike and waves and poly spike wave-paroxysms. We refer the small number of positive findings in the mobile long-term EEG mainly to the fact that only 3 EEG canals are disponible until now. Therefore on the one hand it is not definitly possible to distinguish sharp waves from sharp transients physiologically appearing in sleep, on the other hand focal EEG-changes often escape from being recorded.

Social and medical aspects of epilepsy in northern Norway.

SUMMARYA review is presented of the status and care of epileptic patients in northern Norway. Problems related to the geographically isolated position, difficult climatic conditions and thinly distributed population are discussed.The present investigation leads to the conclusion that the reporting and control of patients with epilepsy is not yet fully adequate and has to be intensified, especially in the peripheral districts. Measures to improve this situation are suggested which include a mobile EEG unit, courses for personnel involved in the care of the epileptics and the future establishment of a special centre.

Mobile EEG diagnostic unit of the Michigan Epilepsy Center and Association.

The total mobile unit service of the Michigan Epilepsy Center and Association (MECA) includes electroencephalography (EEG), neurological consultation, neurological examination, and lectures on epilepsy. From the physician's referral information and the patient's previous medical and hospital contacts and social-medical history, the neurologist adds to the EEG report his diagnostic considerations and suggestions for the continued management of the patient. The referring physician therefore receives both the EEG report and neurological consultation. The very presence of this diagnostic laboratory in an area tends to strengthen the patient-doctor relationship in many instances. One major problem for the mobile unit, which is still not satisfactorily solved, concerns the ideal for which the MECA stands, namely, a total approach, with use of many medical and allied disciplines to determine the causes and the treatment program for each patient.