Current Distribution in the Brain From Surface Electrodes

1968 ◽  
Vol 47 (6) ◽  
pp. 717???723 ◽  
Author(s):  
STANLEY RUSH ◽  
DANIEL A. DRISCOLL
Keyword(s):  
Current Distribution ◽  
Surface Electrodes ◽  
The Brain

scholarly journals Sleep and gastric function in irritable bowel syndrome: derailing the brain-gut axis

Gut ◽  
1997 ◽  
Vol 41 (3) ◽  
pp. 390-393 ◽  
Author(s):  
W C Orr ◽  
M D Crowell ◽  
B Lin ◽  
M J Harnish ◽  
J D Z Chen
Keyword(s):  
Irritable Bowel Syndrome ◽  
Rem Sleep ◽  
Bowel Function ◽  
Control Group ◽  
Gastric Function ◽  
Subsequent Increase ◽  
Surface Electrodes ◽  
Non Invasive ◽  
Irritable Bowel ◽  
The Brain

Background—Recently, several studies have shown an alteration in bowel function during sleep in patients with irritable bowel syndrome (IBS), and a recent study also suggests a remarkable increase in rapid eye movement (REM) sleep. These studies have suggested that an alteration in CNS function may play an important role in the pathogenesis of IBS.Aims—To confirm the presence of an alteration in REM sleep in patients with IBS and to assess the relation between sleep and a non-invasive measure of gastric functioning, the electrogastrogram (EGG).Patients—Ten patients with IBSand 10 age and sex matched normal volunteers.Methods—All subjects slept one night in the sleep laboratory and underwent polysomnographic monitoring to determine sleep patterns, and recording of the EGG from surface electrodes.Results—The IBS group had a notable and significant increase in the percentage and duration of REM sleep (p<0.05). The control group had a decrease in the amplitude of the dominant EGG frequency from waking to non-REM sleep (p<0.05), and a subsequent increase in the amplitude from non-REM to REM sleep (p<0.05). No such changes were noted in the patients with IBS.Conclusions—Results confirmed the enhancement of REM sleep in patients with IBS and suggested an intrinsic alteration in autonomic and CNS functioning in patients with IBS.

EMG based Exoskeleton for Left Hemiplegia patients

2021 ◽  
Vol 23 (05) ◽  
pp. 471-478
Author(s):  
A N Nithyaa ◽  
◽  
R. Premkumar ◽  
M Gokul ◽  
C Geetha Aanandhi ◽  
...  
Keyword(s):  
Blood Supply ◽  
Muscle Function ◽  
The Body ◽  
Daily Activities ◽  
Severe Stroke ◽  
Surface Electrodes ◽  
Emg Signal ◽  
Rehabilitation System ◽  
The Brain ◽  
Flexion And Extension

Paralysis is a condition in which the muscle function is lost in a part of the body. Paralysis is mainly caused as a result of severe stroke, where in the blood supply to a part of the brain is cut off. Hemiplegiais a type of paralysis which affects half of the body includes one arm and one leg on the same side of the body. The case of left Hemiplegia is taken into account, which is caused by the absence of blood supply to the righthemisphere of the brain. Stationary systems like Lokomat, used in the rehabilitation centres to assist training, provide highly repetitive action and just assistance to the patient’s capabilities while walking on a treadmill. However these systems are not portable and cannot be used for home or daily activities. To overcome this, this paper presents the rehabilitation system, which comprises of an exoskeleton that aids the movement of the left upper limb. The entire system is driven by a motor through a microcontroller system which assists patient’s flexion and extension movements. Meanwhile, EMG signal can be recorded by placing surface electrodes to know the recovery of physiological motor function.

scholarly journals Cerebrocortical Microcirculation in Different Stages of Hypoxic Hypoxia

1987 ◽  
Vol 7 (4) ◽  
pp. 464-470 ◽  
Author(s):  
Ewa Kozniewska ◽  
Lutz Weller ◽  
Jens Höper ◽  
David K. Harrison ◽  
Manfred Kessler
Keyword(s):  
Oxygen Tension ◽  
Brain Cortex ◽  
Critical Level ◽  
Hypoxic Hypoxia ◽  
Regulatory Mechanisms ◽  
Mechanically Ventilated ◽  
Surface Electrodes ◽  
Local Tissue ◽  
The Mean ◽  
The Brain

This study investigated the relation between local cerebrocortical oxygen tension (PO2) and cerebrocortical microflow (CMF) during normoxia (Fio2 = 0.3) and hypoxic hypoxemia (Fio2 = 0.16 and 0.1). Measurements were performed on mechanically ventilated rats and rabbits anesthetized with 0.8% Ethrane and maintained within normocapnic limits. Polarographic techniques based on the use of multiwire surface electrodes were applied for measurements of local PO2 and CMF. In both species the mean tissue PO2 values were similar under normoxia (26.0 and 31.5 mm Hg for rats and rabbits, respectively). CMF histograms showed pronounced heterogeneity. The highest CMF values exceeded the lowest ones by a factor of 36 in the rat and by a factor of 26 in the rabbit. Mean CMF values were 6.67 ± 0.72 and 4.09 ± 0.14 relative units (for definition see text) in rats and rabbits, respectively. During hypoxemia, if the mean tissue Po2 was >5 mm Hg, mean CMF did not change but a change in the pattern of microflow distribution was observed with increases in some CMF values (up to 670% of control) and decreases in others (down to 12% of control). When mean tissue Po2 values of <5 mm Hg were observed during hypoxemia, mean CMF increased in both species by ∼50% on average. The increase in CMF could be seen in each individual CMF recording. We conclude that in the brain cortex local regulatory mechanisms are responsible for the change in the pattern of distribution of microcirculation during moderate tissue hypoxia. The same or similar mechanisms produce an increase in microflow if the local tissue Po2 falls below a critical level. Our experiments show that this critical level lies within the range of 0–5 mm Hg.

scholarly journals On the Inverse EEG Problem for a 1D Current Distribution

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
George Dassios ◽  
George Fragoyiannis ◽  
Konstantia Satrazemi
Keyword(s):  
Current Distribution ◽  
Three Dimensional ◽  
Spherical Model ◽  
One Dimensional ◽  
Special Cases ◽  
Nonlinear Algebraic System ◽  
Arbitrary Location ◽  
Spherical Conductor ◽  
The Brain ◽  
A Current

Albanese and Monk (2006) have shown that, it is impossible to recover the support of a three-dimensional current distribution within a conducting medium from the knowledge of the electric potential outside the conductor. On the other hand, it is possible to obtain the support of a current which lives in a subspace of dimension lower than three. In the present work, we actually demonstrate this possibility by assuming a one-dimensional current distribution supported on a small line segment having arbitrary location and orientation within a uniform spherical conductor. The immediate representation of this problem refers to the inverse problem of electroencephalography (EEG) with a linear current distribution and the spherical model of the brain-head system. It is shown that the support is identified through the solution of a nonlinear algebraic system which is investigated thoroughly. Numerical tests show that this system has exactly one real solution. Exact solutions are analytically obtained for a couple of special cases.

Motor Restoration Based on the Brain–Machine Interface Using Brain Surface Electrodes: Real-Time Robot Control and a Fully Implantable Wireless System

2012 ◽  
Vol 26 (3-4) ◽  
pp. 399-408 ◽  
Author(s):  
Masayuki Hirata ◽  
Kojiro Matsushita ◽  
Takufumi Yanagisawa ◽  
Tetsu Goto ◽  
Shayne Morris ◽  
...  
Keyword(s):  
Real Time ◽  
Robot Control ◽  
Brain Machine Interface ◽  
Wireless System ◽  
Surface Electrodes ◽  
Brain Surface ◽  
Machine Interface ◽  
The Brain

EMG based Exoskeleton for Left Hemiplegia patients

2021 ◽  
Vol 23 (05) ◽  
pp. 471-478
Author(s):  
A N Nithyaa ◽  
◽  
R. Premkumar ◽  
M Gokul ◽  
C Geetha Aanandhi ◽  
...  
Keyword(s):  
Blood Supply ◽  
Muscle Function ◽  
The Body ◽  
Daily Activities ◽  
Severe Stroke ◽  
Surface Electrodes ◽  
Emg Signal ◽  
Rehabilitation System ◽  
The Brain ◽  
Flexion And Extension

Paralysis is a condition in which the muscle function is lost in a part of the body. Paralysis is mainly caused as a result of severe stroke, where in the blood supply to a part of the brain is cut off. Hemiplegiais a type of paralysis which affects half of the body includes one arm and one leg on the same side of the body. The case of left Hemiplegia is taken into account, which is caused by the absence of blood supply to the righthemisphere of the brain. Stationary systems like Lokomat, used in the rehabilitation centres to assist training, provide highly repetitive action and just assistance to the patient’s capabilities while walking on a treadmill. However these systems are not portable and cannot be used for home or daily activities. To overcome this, this paper presents the rehabilitation system, which comprises of an exoskeleton that aids the movement of the left upper limb. The entire system is driven by a motor through a microcontroller system which assists patient’s flexion and extension movements. Meanwhile, EMG signal can be recorded by placing surface electrodes to know the recovery of physiological motor function.

scholarly journals Surface electrodes record and label brain neurons in insects

2017 ◽  
Vol 118 (5) ◽  
pp. 2884-2889 ◽  
Author(s):  
Konstantinos Kostarakos ◽  
Berthold Hedwig
Keyword(s):  
Dendritic Structure ◽  
Extracellular Recording ◽  
Projection Area ◽  
Neural Processing ◽  
Auditory Neurons ◽  
Surface Electrodes ◽  
Brain Surface ◽  
Versatile Tool ◽  
Cricket Brain ◽  
The Brain

We used suction electrodes to reliably record the activity of identified ascending auditory interneurons from the anterior surface of the brain in crickets. Electrodes were gently attached to the sheath covering the projection area of the ascending interneurons and the ringlike auditory neuropil in the protocerebrum. The specificity and selectivity of the recordings were determined by the precise electrode location, which could easily be changed without causing damage to the tissue. Different nonauditory fibers were recorded at other spots of the brain surface; stable recordings lasted for several hours. The same electrodes were used to deliver fluorescent tracers into the nervous system by means of electrophoresis. This allowed us to retrograde label the recorded auditory neurons and to reveal their cell body and dendritic structure in the first thoracic ganglion. By adjusting the amount of dye injected, we specifically stained the ringlike auditory neuropil in the brain, demonstrating the clusters of cell bodies contributing to it. Our data provide a proof that surface electrodes are a versatile tool to analyze neural processing in small brains of invertebrates. NEW & NOTEWORTHY We show that surface suction electrodes can be used to monitor the activity of auditory neurons in the cricket brain. They also allow delivering electrophoretically a fluorescent tracer to label the structure of the recorded neurons and the local neuropil to which the electrode was attached. This new extracellular recording and labeling technique is a versatile and useful method to explore neural processing in invertebrate sensory and motor systems.

Sign in / Sign up

Export Citation Format

Share Document