Hypnotisability and the Cerebellum: Hypotheses and Perspectives

The Cerebellum ◽

10.1007/s12311-021-01292-1 ◽

2021 ◽

Author(s):

Enrica Laura Santarcangelo ◽

Diego Manzoni

Keyword(s):

Motor Cortex ◽

Cortical Inhibition ◽

Future Research ◽

Grey Matter Volume ◽

Physiological Mechanisms ◽

Cerebellar Inhibition ◽

Motor Excitability ◽

Psychophysiological Correlates ◽

Review Reports ◽

The Right

AbstractHypnotisability is a multidimensional trait predicting the proneness to enter hypnosis and/or accept suggestions and is associated with several psychophysiological correlates. This scoping review reports the differences between individuals with high (highs) and low hypnotizability (lows) in the left cerebellar lobules IV–VI grey matter volume, in the excitability of the right motor cortex and in motor and non-motor functions in which the cerebellum may be involved. A reduced cerebellar inhibition may explain the greater excitability of the highs’ right motor cortex. The latter may be involved in their greater proneness to ideomotor behaviour following sensorimotor suggestions. The associated experience of involuntariness and effortlessness could be due to the motor cortex greater excitability as well as to activation of a specific cerebellar-parietal circuit. Looser postural and visuomotor control with no learning across trials and greater attentional stability can be accounted for by a less accurate cerebellar predictive model of information processing. The highs’ stronger functional equivalence between imagery and perception/action and greater motor excitability may be involved in the highs’ greater proneness to respond to emotional stimuli. Paradoxical pain control may depend on reduced cortical inhibition of the pain matrix by the cerebellum. Cerebellar hypotheses are not alternative to other physiological mechanisms and should be tested in future research.

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Can machine learning extract the mechanisms controlling phytoplankton growth from large-scale observations? – A proof-of-concept study

Biogeosciences ◽

10.5194/bg-18-1941-2021 ◽

2021 ◽

Vol 18 (6) ◽

pp. 1941-1970

Author(s):

Christopher Holder ◽

Anand Gnanadesikan

Keyword(s):

Machine Learning ◽

Large Scale ◽

Phytoplankton Growth ◽

Qualitative Assessment ◽

Future Research ◽

Proof Of Concept ◽

Physiological Mechanisms ◽

Concept Study ◽

Phytoplankton Growth Rate ◽

The Right

Abstract. A key challenge for biological oceanography is relating the physiological mechanisms controlling phytoplankton growth to the spatial distribution of those phytoplankton. Physiological mechanisms are often isolated by varying one driver of growth, such as nutrient or light, in a controlled laboratory setting producing what we call “intrinsic relationships”. We contrast these with the “apparent relationships” which emerge in the environment in climatological data. Although previous studies have found machine learning (ML) can find apparent relationships, there has yet to be a systematic study examining when and why these apparent relationships diverge from the underlying intrinsic relationships found in the lab and how and why this may depend on the method applied. Here we conduct a proof-of-concept study with three scenarios in which biomass is by construction a function of time-averaged phytoplankton growth rate. In the first scenario, the inputs and outputs of the intrinsic and apparent relationships vary over the same monthly timescales. In the second, the intrinsic relationships relate averages of drivers that vary on hourly timescales to biomass, but the apparent relationships are sought between monthly averages of these inputs and monthly-averaged output. In the third scenario we apply ML to the output of an actual Earth system model (ESM). Our results demonstrated that when intrinsic and apparent relationships operate on the same spatial and temporal timescale, neural network ensembles (NNEs) were able to extract the intrinsic relationships when only provided information about the apparent relationships, while colimitation and its inability to extrapolate resulted in random forests (RFs) diverging from the true response. When intrinsic and apparent relationships operated on different timescales (as little separation as hourly versus daily), NNEs fed with apparent relationships in time-averaged data produced responses with the right shape but underestimated the biomass. This was because when the intrinsic relationship was nonlinear, the response to a time-averaged input differed systematically from the time-averaged response. Although the limitations found by NNEs were overestimated, they were able to produce more realistic shapes of the actual relationships compared to multiple linear regression. Additionally, NNEs were able to model the interactions between predictors and their effects on biomass, allowing for a qualitative assessment of the colimitation patterns and the nutrient causing the most limitation. Future research may be able to use this type of analysis for observational datasets and other ESMs to identify apparent relationships between biogeochemical variables (rather than spatiotemporal distributions only) and identify interactions and colimitations without having to perform (or at least performing fewer) growth experiments in a lab. From our study, it appears that ML can extract useful information from ESM output and could likely do so for observational datasets as well.

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Mirror illusion reduces motor cortical inhibition in the ipsilateral primary motor cortex during forceful unilateral muscle contractions

Journal of Neurophysiology ◽

10.1152/jn.00686.2014 ◽

2015 ◽

Vol 113 (7) ◽

pp. 2262-2270 ◽

Cited By ~ 12

Author(s):

Tjerk Zult ◽

Stuart Goodall ◽

Kevin Thomas ◽

Tibor Hortobágyi ◽

Glyn Howatson

Keyword(s):

Motor Cortex ◽

Primary Motor Cortex ◽

Short Interval ◽

Mirror Image ◽

Corticospinal Excitability ◽

Cortical Inhibition ◽

Electromyographic Activity ◽

Wrist Flexion ◽

Motor Cortical ◽

The Right

Forceful, unilateral contractions modulate corticomotor paths targeting the resting, contralateral hand. However, it is unknown whether mirror-viewing of a slowly moving but forcefully contracting hand would additionally affect these paths. Here we examined corticospinal excitability and short-interval intracortical inhibition (SICI) of the right-ipsilateral primary motor cortex (M1) in healthy young adults under no-mirror and mirror conditions at rest and during right wrist flexion at 60% maximal voluntary contraction (MVC). During the no-mirror conditions neither hand was visible, whereas in the mirror conditions participants looked at the right hand's reflection in the mirror. Corticospinal excitability increased during contractions in the left flexor carpi radialis (FCR) (contraction 0.41 mV vs. rest 0.21 mV) and extensor carpi radialis (ECR) (contraction 0.56 mV vs. rest 0.39 mV), but there was no mirror effect (FCR: P = 0.743, ηp2= 0.005; ECR: P = 0.712, ηp2= 0.005). However, mirror-viewing of the contracting and moving wrist attenuated SICI relative to test pulse in the left FCR by ∼9% compared with the other conditions ( P < 0.05, d ≥ 0.62). Electromyographic activity in the resting left hand prior to stimulation was not affected by the mirror (FCR: P = 0.255, ηp2= 0.049; ECR: P = 0.343, ηp2= 0.035) but increased twofold during contractions. Thus viewing the moving hand in the mirror and not just the mirror image of the nonmoving hand seems to affect motor cortical inhibitory networks in the M1 associated with the mirror image. Future studies should determine whether the use of a mirror could increase interlimb transfer produced by cross-education, especially in patient groups with unilateral orthopedic and neurological conditions.

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The effect of muscle fatigue on cortico-cortical inhibition and facilitation in human motor cortex

Electroencephalography and Clinical Neurophysiology ◽

10.1016/s0013-4694(97)88702-4 ◽

1997 ◽

Vol 103 (1) ◽

pp. 153

Author(s):

A Maruyama

Keyword(s):

Motor Cortex ◽

Muscle Fatigue ◽

Cortical Inhibition ◽

Human Motor Cortex ◽

Human Motor

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Transferrin-Conjugated Nanocarriers as Active-Targeted Drug Delivery Platforms for Cancer Therapy

Current Pharmaceutical Design ◽

10.2174/1381612822666161026162347 ◽

2017 ◽

Vol 23 (3) ◽

pp. 454-466 ◽

Cited By ~ 16

Author(s):

Daniele R. Nogueira-Librelotto ◽

Cristiane F. Codevilla ◽

Ammad Farooqi ◽

Clarice M. B. Rolim

Keyword(s):

Drug Delivery ◽

Cancer Therapy ◽

Tumor Cells ◽

Therapeutic Benefit ◽

Active Targeting ◽

Future Research ◽

Passive Targeting ◽

The Right ◽

Review Current ◽

Target Effects

A lot of effort has been devoted to achieving active targeting for cancer therapy in order to reach the right cells. Hence, increasingly it is being realized that active-targeted nanocarriers notably reduce off-target effects, mainly because of targeted localization in tumors and active cellular uptake. In this context, by taking advantage of the overexpression of transferrin receptors on the surface of tumor cells, transferrin-conjugated nanodevices have been designed, in hope that the biomarker grafting would help to maximize the therapeutic benefit and to minimize the side effects. Notably, active targeting nanoparticles have shown improved therapeutic performances in different tumor models as compared to their passive targeting counterparts. In this review, current development of nano-based devices conjugated with transferrin for active tumor-targeting drug delivery are highlighted and discussed. The main objective of this review is to provide a summary of the vast types of nanomaterials that have been used to deliver different chemotherapeutics into tumor cells, and to ultimately evaluate the progression on the strategies for cancer therapy in view of the future research.

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Reduced Interhemispheric Coherence in Cerebellar Kainic Acid-Induced Lateralized Dystonia

Frontiers in Neurology ◽

10.3389/fneur.2020.580540 ◽

2020 ◽

Vol 11 ◽

Author(s):

Elena Laura Georgescu Margarint ◽

Ioana Antoaneta Georgescu ◽

Carmen Denise Mihaela Zahiu ◽

Stefan-Alexandru Tirlea ◽

Alexandru Rǎzvan Şteopoaie ◽

...

Keyword(s):

Motor Cortex ◽

Kainic Acid ◽

Primary Motor Cortex ◽

Low Frequency ◽

Muscular Activity ◽

Cerebellar Hemisphere ◽

Interhemispheric Coherence ◽

General Locomotor Activity ◽

Complex Circuits ◽

The Right

The execution of voluntary muscular activity is controlled by the primary motor cortex, together with the cerebellum and basal ganglia. The synchronization of neural activity in the intracortical network is crucial for the regulation of movements. In certain motor diseases, such as dystonia, this synchrony can be altered in any node of the cerebello-cortical network. Questions remain about how the cerebellum influences the motor cortex and interhemispheric communication. This research aims to study the interhemispheric cortical communication between the motor cortices during dystonia, a neurological movement syndrome consisting of sustained or repetitive involuntary muscle contractions. We pharmacologically induced lateralized dystonia to adult male albino mice by administering low doses of kainic acid on the left cerebellar hemisphere. Using electrocorticography and electromyography, we investigated the power spectral densities, cortico-muscular, and interhemispheric coherence between the right and left motor cortices, before and during dystonia, for five consecutive days. Mice displayed lateralized abnormal motor signs, a reduced general locomotor activity, and a high score of dystonia. The results showed a progressive interhemispheric coherence decrease in low-frequency bands (delta, theta, beta) during the first 3 days. The cortico-muscular coherence of the affected side had a significant increase in gamma bands on days 3 and 4. In conclusion, lateralized cerebellar dysfunction during dystonia was associated with a loss of connectivity in the motor cortices, suggesting a possible cortical compensation to the initial disturbances induced by cerebellar left hemisphere kainate activation by blocking the propagation of abnormal oscillations to the healthy hemisphere. However, the cerebellum is part of several overly complex circuits, therefore other mechanisms can still be involved in this phenomenon.

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Effect of Transcranial Magnetic Stimulation on Bimanual Movements

Journal of Neurophysiology ◽

10.1152/jn.01063.2003 ◽

2005 ◽

Vol 93 (1) ◽

pp. 53-63 ◽

Cited By ~ 19

Author(s):

Jen-Tse Chen ◽

Yung-Yang Lin ◽

Din-E Shan ◽

Zin-An Wu ◽

Mark Hallett ◽

...

Keyword(s):

Transcranial Magnetic Stimulation ◽

Motor Cortex ◽

Left Hemisphere ◽

Magnetic Stimulation ◽

Normal Subjects ◽

Left Index Finger ◽

Rhythmic Movements ◽

Bimanual Movements ◽

Ipsilateral Stimulation ◽

The Right

Transcranial magnetic stimulation (TMS) of the motor cortex can interrupt voluntary contralateral rhythmic limb movements. Using the method of “resetting index” (RI), our study investigated the TMS effect on different types of bimanual movements. Six normal subjects participated. For unimanual movement, each subject tapped either the right or left index finger at a comfortable rate. For bimanual movement, index fingers of both hands tapped in the same (in-phase) direction or in the opposite (antiphase) direction. TMS was applied to each hemisphere separately at various intensities from 0.5 to 1.5 times motor threshold (MT). TMS interruption of rhythm was quantified by RI. For the unimanual movements, TMS disrupted both contralateral and ipsilateral rhythmic hand movements, although the effect was much less in the ipsilateral hand. For the bimanual in-phase task, TMS could simultaneously reset the rhythmic movements of both hands, but the effect on the contralateral hand was less and the effect on the ipsilateral hand was more compared with the unimanual tasks. Similar effects were seen from right and left hemisphere stimulation. TMS had little effect on the bimanual antiphase task. The equal effect of right and left hemisphere stimulation indicates that neither motor cortex is dominant for simple bimanual in-phase movement. The smaller influence of contralateral stimulation and the greater effect of ipsilateral stimulation during bimanual in-phase movement compared with unimanual movement suggest hemispheric coupling. The antiphase movements were resistant to TMS disruption, and this suggests that control of rhythm differs in the 2 tasks. TMS produced a transient asynchrony of movements on the 2 sides, indicating that both motor cortices might be downstream of the clocking command or that the clocking is a consequence of the 2 hemispheres communicating equally with each other.

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The impact of regionalized trauma care on the distribution of severely injured patients in the Netherlands

European Journal of Trauma and Emergency Surgery ◽

10.1007/s00068-021-01615-1 ◽

2021 ◽

Author(s):

Suzan Dijkink ◽

Erik W. van Zwet ◽

Pieta Krijnen ◽

Luke P. H. Leenen ◽

Frank W. Bloemers ◽

...

Keyword(s):

The Netherlands ◽

Trauma Care ◽

Trauma System ◽

Future Research ◽

Severely Injured ◽

Trauma Centers ◽

Severely Injured Patients ◽

The Right ◽

Injured Patients ◽

The Impact

Abstract Background Twenty years ago, an inclusive trauma system was implemented in the Netherlands. The goal of this study was to evaluate the impact of structured trauma care on the concentration of severely injured patients over time. Methods All severely injured patients (Injury Severity Score [ISS] ≥ 16) documented in the Dutch Trauma Registry (DTR) in the calendar period 2008–2018 were included for analysis. We compared severely injured patients, with and without severe neurotrauma, directly brought to trauma centers (TC) and non-trauma centers (NTC). The proportion of patients being directly transported to a trauma center was determined, as was the total Abbreviated Injury Score (AIS), and ISS. Results The documented number of severely injured patients increased from 2350 in 2008 to 4694 in 2018. During this period, on average, 70% of these patients were directly admitted to a TC (range 63–74%). Patients without severe neurotrauma had a lower chance of being brought to a TC compared to those with severe neurotrauma. Patients directly presented to a TC were more severely injured, reflected by a higher total AIS and ISS, than those directly transported to a NTC. Conclusion Since the introduction of a well-organized trauma system in the Netherlands, trauma care has become progressively centralized, with more severely injured patients being directly presented to a TC. However, still 30% of these patients is initially brought to a NTC. Future research should focus on improving pre-hospital triage to facilitate swift transfer of the right patient to the right hospital.

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A Review of Reductionist versus Systems Perspectives towards ‘Doing the Right Strategies Right’ for Circular Economy Implementation

Systems ◽

10.3390/systems9020038 ◽

2021 ◽

Vol 9 (2) ◽

pp. 38

Author(s):

Raquel Balanay ◽

Anthony Halog

Keyword(s):

Circular Economy ◽

Systems Approach ◽

Holistic Approach ◽

Comprehensive Analysis ◽

Unintended Consequences ◽

Review Reports ◽

The Right ◽

Business As Usual ◽

Analytical Frameworks ◽

Reductionist Approach

This systematic review examines the importance of a systems/holistic approach in analyzing and addressing the footprints/impacts of business-as-usual activities regarding the development of a circular economy (CE). Recent works on why current CE approaches have to be examined in terms of reductionist vs. systems perspectives are reviewed to tackle questions pertaining to the right or the wrong way of CE implementation. ‘Doing the right thing right’ is essential for sustainability—the ultimate goal of a CE, which must be viewed as a system to begin with. The limited reductionist approach overlooks and thus cannot prognosticate on the formidable unintended consequences that emerge from ‘doing the right things wrong’, consequences that become too costly to undo. The systems approach, being holistic, is complicated and difficult to pursue but open to exciting opportunities to integrate innovations in CE analysis and implementation. Complexity is an inherent downside of the systems approach. However, both approaches are complementary, as reductionist models can be combined to create a system of comprehensive analysis to correct the approach towards implementation of current CE initiatives. This review reports that advancements in systems analytical frameworks and tools are highly important for creating general guidelines on CE analysis and implementation.

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Sudden Unexpected Death Associated with Arrhythmogenic Cardiomyopathy: Study of the Cardiac Conduction System

Diagnostics ◽

10.3390/diagnostics11081323 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1323

Author(s):

Giulia Ottaviani ◽

Graziella Alfonsi ◽

Simone G. Ramos ◽

L. Maximilian Buja

Keyword(s):

Fibromuscular Dysplasia ◽

Ventricular Myocardium ◽

Conduction System ◽

Cardiac Conduction ◽

Future Research ◽

Cardiac Conduction System ◽

Arrhythmogenic Cardiomyopathy ◽

Unexpected Death ◽

The Past ◽

The Right

A retrospective study was conducted on pathologically diagnosed arrhythmogenic cardiomyopathy (ACM) from consecutive cases over the past 34 years (n = 1109). The anatomo-pathological analyses were performed on 23 hearts diagnosed as ACM (2.07%) from a series of 1109 suspected cases, while histopathological data of cardiac conduction system (CCS) were available for 15 out of 23 cases. The CCS was removed in two blocks, containing the following structures: Sino-atrial node (SAN), atrio-ventricular junction (AVJ) including the atrio-ventricular node (AVN), the His bundle (HB), the bifurcation (BIF), the left bundle branch (LBB) and the right bundle branch (RBB). The ACM cases consisted of 20 (86.96%) sudden unexpected cardiac death (SUCD) and 3 (13.04%) native explanted hearts; 16 (69.56%) were males and 7 (30.44%) were females, ranging in age from 5 to 65 (mean age ± SD, 36.13 ± 16.06) years. The following anomalies of the CCS, displayed as percentages of the 15 ACM SUCD cases in which the CCS has been fully analyzed, have been detected: Hypoplasia of SAN (80%) and/or AVJ (86.67%) due to fatty-fibrous involvement, AVJ dispersion and/or septation (46.67%), central fibrous body (CFB) hypoplasia (33.33%), fibromuscular dysplasia of SAN (20%) and/or AVN (26.67%) arteries, hemorrhage and infarct-like lesions of CCS (13.33%), islands of conduction tissue in CFB (13.33%), Mahaim fibers (13.33%), LBB block by fibrosis (13.33%), AVN tongue (13.33%), HB duplicity (6.67%%), CFB cartilaginous meta-hyperplasia (6.67%), and right sided HB (6.67%). Arrhythmias are the hallmark of ACM, not only from the fatty-fibrous disruption of the ventricular myocardium that accounts for reentrant ventricular tachycardia, but also from the fatty-fibrous involvement of CCS itself. Future research should focus on application of these knowledge on CCS anomalies to be added to diagnostic criteria or at least to be useful to detect the patients with higher sudden death risks.

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