scholarly journals Studying the functional connectivity of the primary motor cortex with the binarized cross recurrence plot: The influence of Parkinson’s disease

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0252565
Author(s):  
Clara Rodriguez-Sabate ◽  
Manuel Rodriguez ◽  
Ingrid Morales
Keyword(s):  
Motor Cortex ◽  
Somatosensory Cortex ◽  
Primary Motor Cortex ◽  
Recurrence Plot ◽  
Primary Somatosensory Cortex ◽  
Functional Interactions ◽  
Task Block ◽  
Motor Thalamus ◽  
Cross Recurrence Plot

Two new recurrence plot methods (the binary recurrence plot and binary cross recurrence plot) were introduced here to study the long-term dynamic of the primary motor cortex and its interaction with the primary somatosensory cortex, the anterior motor thalamus of the basal ganglia motor loop and the precuneous nucleus of the default mode network. These recurrence plot methods: 1. identify short-term transient interactions; 2. identify long-lasting delayed interactions that are common in complex systems; 3. work with non-stationary blood oxygen level dependent (BOLD) data; 4. may study the relationship of centers with non-linear functional interactions; 5 may compare different experimental groups performing different tasks. These methods were applied to BOLD time-series obtained in 20 control subjects and 20 Parkinson´s patients during the execution of motor activity and body posture tasks (task-block design). The binary recurrence plot showed the task-block BOLD response normally observed in the primary motor cortex with functional magnetic resonance imaging methods, but also shorter and longer BOLD-fluctuations than the task-block and which provided information about the long-term dynamic of this center. The binary cross recurrence plot showed short-lasting and long-lasting functional interactions between the primary motor cortex and the primary somatosensory cortex, anterior motor thalamus and precuneous nucleus, interactions which changed with the resting and motor tasks. Most of the interactions found in healthy controls were disrupted in Parkinson’s patients, and may be at the basis of some of the motor disorders and side-effects of dopaminergic drugs commonly observed in these patients.

scholarly journals Layer-specific sensory processing impairment in the primary somatosensory cortex after motor cortex infarction

2019 ◽  
Author(s):  
Atsushi Fukui ◽  
Hironobu Osaki ◽  
Yoshifumi Ueta ◽  
Yoshihiro Muragaki ◽  
Takakazu Kawamata ◽  
...  
Keyword(s):  
Motor Cortex ◽  
Somatosensory Cortex ◽  
Acute Phase ◽  
Sensory Processing ◽  
Primary Motor Cortex ◽  
Temporal Coding ◽  
Network Activity ◽  
Primary Somatosensory Cortex ◽  
Inhibitory Input ◽  
Sensory Impairment

AbstractPrimary motor cortex (M1) infarction occasionally causes sensory impairment. Because sensory signal plays an important role in motor control, sensory impairment compromises recovery and rehabilitation from motor disability. Despite the importance of sensory-motor integration for rehabilitation after M1 infarction, the neural mechanism of the sensory impairment is poorly understood. We show that the sensory processing in the primary somatosensory cortex (S1) was impaired in the acute phase of M1 infarction and recovered in a layer-specific manner in the subacute phase. This layer dependent recovery process and the anatomical connection pattern from M1 to S1 suggested the functional connectivity from M1 to S1 plays a key role in the impairment of sensory processing in S1. The simulation study demonstrated that the loss of inhibition from M1 to S1 in the acute phase of M1 infarction could cause the sensory processing impairment in S1, and the complementation of inhibition could recover the temporal coding. Taken together, we revealed how focal stroke of M1 alters cortical network activity of sensory processing, in which inhibitory input from M1 to S1 may be involved.

Long-term neuroplasticity of the face primary motor cortex and adjacent somatosensory cortex induced by tooth loss can be reversed following dental implant replacement in rats

2015 ◽  
Vol 523 (16) ◽  
pp. 2372-2389 ◽  
Author(s):  
Limor Avivi-Arber ◽  
Jye-Chang Lee ◽  
Mandeep Sood ◽  
Flavia Lakschevitz ◽  
Michelle Fung ◽  
...  
Keyword(s):  
Motor Cortex ◽  
Somatosensory Cortex ◽  
Dental Implant ◽  
Tooth Loss ◽  
Primary Motor Cortex ◽  
The Face

scholarly journals Locating primary somatosensory cortex in human brain stimulation studies: experimental evidence

2019 ◽  
Vol 121 (1) ◽  
pp. 336-344 ◽  
Author(s):  
Nicholas Paul Holmes ◽  
Luigi Tamè ◽  
Paisley Beeching ◽  
Mary Medford ◽  
Mariyana Rakova ◽  
...  
Keyword(s):  
Motor Cortex ◽  
Human Brain ◽  
Somatosensory Cortex ◽  
Brain Stimulation ◽  
Magnetic Stimulation ◽  
Primary Motor Cortex ◽  
Primary Somatosensory Cortex ◽  
Indirect Methods ◽  
Scalp Location ◽  
Hand Area

Transcranial magnetic stimulation (TMS) over human primary somatosensory cortex (S1) does not produce immediate outputs. Researchers must therefore rely on indirect methods for TMS coil positioning. The “gold standard” is to use individual functional and structural magnetic resonance imaging (MRI) data, but the majority of studies don’t do this. The most common method to locate the hand area of S1 (S1-hand) is to move the coil posteriorly from the hand area of primary motor cortex (M1-hand). Yet, S1-hand is not directly posterior to M1-hand. We localized the index finger area of S1-hand (S1-index) experimentally in four ways. First, we reanalyzed functional MRI data from 20 participants who received vibrotactile stimulation to their 10 digits. Second, to assist the localization of S1-hand without MRI data, we constructed a probabilistic atlas of the central sulcus from 100 healthy adult MRIs and measured the likely scalp location of S1-index. Third, we conducted two experiments mapping the effects of TMS across the scalp on tactile discrimination performance. Fourth, we examined all available neuronavigation data from our laboratory on the scalp location of S1-index. Contrary to the prevailing method, and consistent with systematic review evidence, S1-index is close to the C3/C4 electroencephalography (EEG) electrode locations on the scalp, ~7–8 cm lateral to the vertex, and ~2 cm lateral and 0.5 cm posterior to the M1-hand scalp location. These results suggest that an immediate revision to the most commonly used heuristic to locate S1-hand is required. The results of many TMS studies of S1-hand need reassessment. NEW & NOTEWORTHY Noninvasive human brain stimulation requires indirect methods to target particular brain areas. Magnetic stimulation studies of human primary somatosensory cortex have used scalp-based heuristics to find the target, typically locating it 2 cm posterior to the motor cortex. We measured the scalp location of the hand area of primary somatosensory cortex and found that it is ~2 cm lateral to motor cortex. Our results suggest an immediate revision of the prevailing method is required.

scholarly journals Locating primary somatosensory cortex in human brain stimulation studies: systematic review and meta-analytic evidence

2019 ◽  
Vol 121 (1) ◽  
pp. 152-162 ◽  
Author(s):  
Nicholas Paul Holmes ◽  
Luigi Tamè
Keyword(s):  
Somatosensory Cortex ◽  
Primary Motor Cortex ◽  
Primary Somatosensory Cortex ◽  
Similar Data ◽  
Indirect Methods ◽  
Gold Standard Method ◽  
Systematic Assessment ◽  
Stereotactic Navigation ◽  
Scalp Location ◽  
Hand Area

Transcranial magnetic stimulation (TMS) over human primary somatosensory cortex (S1), unlike over primary motor cortex (M1), does not produce an immediate, objective output. Researchers must therefore rely on one or more indirect methods to position the TMS coil over S1. The “gold standard” method of TMS coil positioning is to use individual functional and structural magnetic resonance imaging (f/sMRI) alongside a stereotactic navigation system. In the absence of these facilities, however, one common method used to locate S1 is to find the scalp location that produces twitches in a hand muscle (e.g., the first dorsal interosseus, M1-FDI) and then move the coil posteriorly to target S1. There has been no systematic assessment of whether this commonly reported method of finding the hand area of S1 is optimal. To do this, we systematically reviewed 124 TMS studies targeting the S1 hand area and 95 fMRI studies involving passive finger and hand stimulation. Ninety-six TMS studies reported the scalp location assumed to correspond to S1-hand, which was on average 1.5–2 cm posterior to the functionally defined M1-hand area. Using our own scalp measurements combined with similar data from MRI and TMS studies of M1-hand, we provide the estimated scalp locations targeted in these TMS studies of the S1-hand. We also provide a summary of reported S1 coordinates for passive finger and hand stimulation in fMRI studies. We conclude that S1-hand is more lateral to M1-hand than assumed by the majority of TMS studies.

scholarly journals Brain stimulation for arm recovery after stroke (B-STARS): protocol for a randomised controlled trial in subacute stroke patients

BMJ Open ◽  
2017 ◽  
Vol 7 (8) ◽  
pp. e016566
Author(s):  
Eline C C van Lieshout ◽  
Johanna M A Visser-Meily ◽  
Sebastiaan F W Neggers ◽  
H Bart van der Worp ◽  
Rick M Dijkhuizen
Keyword(s):  
Motor Cortex ◽  
Upper Limb ◽  
Brain Stimulation ◽  
Primary Outcome ◽  
Primary Motor Cortex ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Stroke Patients ◽  
Post Stroke ◽  
Subacute Stroke

IntroductionMany patients with stroke have moderate to severe long-term sensorimotor impairments, often including inability to execute movements of the affected arm or hand. Limited recovery from stroke may be partly caused by imbalanced interaction between the cerebral hemispheres, with reduced excitability of the ipsilesional motor cortex while excitability of the contralesional motor cortex is increased. Non-invasive brain stimulation with inhibitory repetitive transcranial magnetic stimulation (rTMS) of the contralesional hemisphere may aid in relieving a post-stroke interhemispheric excitability imbalance, which could improve functional recovery. There are encouraging effects of theta burst stimulation (TBS), a form of TMS, in patients with chronic stroke, but evidence on efficacy and long-term effects on arm function of contralesional TBS in patients with subacute hemiparetic stroke is lacking.Methods and analysisIn a randomised clinical trial, we will assign 60 patients with a first-ever ischaemic stroke in the previous 7–14 days and a persistent paresis of one arm to 10 sessions of real stimulation with TBS of the contralesional primary motor cortex or to sham stimulation over a period of 2 weeks. Both types of stimulation will be followed by upper limb training. A subset of patients will undergo five MRI sessions to assess post-stroke brain reorganisation. The primary outcome measure will be the upper limb function score, assessed from grasp, grip, pinch and gross movements in the action research arm test, measured at 3 months after stroke. Patients will be blinded to treatment allocation. The primary outcome at 3 months will also be assessed in a blinded fashion.Ethics and disseminationThe study has been approved by the Medical Research Ethics Committee of the University Medical Center Utrecht, The Netherlands. The results will be disseminated through (open access) peer-reviewed publications, networks of scientists, professionals and the public, and presented at conferences.Trial registration numberNTR6133

Long-term effect of safinamide on primary motor cortex excitability and plasticity in Parkinson's disease: A TMS study

2021 ◽  
Vol 429 ◽  
pp. 119453
Author(s):  
Valentina D'Onofrio ◽  
Andrea Guerra ◽  
Francesco Asci ◽  
Giovanni Fabbrini ◽  
Alfredo Berardelli ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Motor Cortex ◽  
Primary Motor Cortex ◽  
Term Effect ◽  
Long Term Effect ◽  
Motor Cortex Excitability

The effect of bilateral cold block of the primate face primary somatosensory cortex on the performance of trained tongue-protrusion task and biting tasks

1993 ◽  
Vol 70 (3) ◽  
pp. 985-996 ◽  
Author(s):  
L. D. Lin ◽  
G. M. Murray ◽  
B. J. Sessle
Keyword(s):  
Somatosensory Cortex ◽  
Primary Motor Cortex ◽  
Movement Control ◽  
Primary Somatosensory Cortex ◽  
Emg Activity ◽  
Success Rates ◽  
Tongue Protrusion ◽  
Reversible Inactivation ◽  
Control Series ◽  
Holding Period

1. Studies using ablation, intracortical microstimulation (ICMS) and surface stimulation, and single-neuron recordings have suggested that the primate primary somatosensory cortex (SI) may play an important role in movement control. Our aim was to determine whether bilateral inactivation of face SI would indeed interfere with the control of tongue or jaw-closing movements. 2. Effects of reversible inactivation by cooling of face SI was investigated in two monkeys trained to perform both a tongue-protrusion task and a biting task. The cooling experiments were carried out after the orofacial representation within SI was identified by systematically defining the mechanoreceptive field of single neurons recorded in face SI. The deficits in the tongue or jaw-closing movement were evaluated by the success rates for the monkeys' performance of both tasks and by the force and electromyographic (EMG) activity recorded from the masseter, genioglossus, and digastric muscles associated with the tasks. 3. During bilateral cooling of face SI, there was a statistically significant reduction in the success rates for the performance of the tongue-protrusion task in comparison with control series of trials while the thermodes used to cool face SI were kept at 37 degrees C. Detailed analyses of force and EMG activity showed that the principal deficit was the inability of the monkeys to maintain a steady tongue-protrusive force in the force holding period during each trial and to exert a consistent tongue-protrusion force between different trials. The task performance returned to control protocol levels at 4 min after commencement of rewarming. 4. Identical cooling conditions did not significantly affect the success rates for the performance of the biting task. Although the extent of the deficit was not severe enough to cause a significant reduction in successful rates for the biting task, cooling did significantly affect the ability of the monkeys to maintain a steady force in the holding period during each trial and to exert a consistent force between different trials. In one monkey the success rate of the biting task was also not affected by bilaterally cooling of face SI with a pair of larger thermodes placed on the dura over most of the face SI, face primary motor cortex (face MI), and adjacent cortical regions.(ABSTRACT TRUNCATED AT 400 WORDS)

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