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Journal of Psychosomatic Research Apr 2024Catatonia is a challenging and heterogeneous neuropsychiatric syndrome of motor, affective and behavioral dysregulation which has been associated with multiple disorders... (Review)
Review
BACKGROUND
Catatonia is a challenging and heterogeneous neuropsychiatric syndrome of motor, affective and behavioral dysregulation which has been associated with multiple disorders such as structural brain lesions, systemic diseases, and psychiatric disorders. This systematic review summarized and compared functional neuroimaging abnormalities in catatonia associated with psychiatric and medical conditions.
METHODS
Using PRISMA methods, we completed a systematic review of 6 databases from inception to February 7th, 2024 of patients with catatonia that had functional neuroimaging performed.
RESULTS
A total of 309 studies were identified through the systematic search and 62 met the criteria for full-text review. A total of 15 studies reported patients with catatonia associated with a psychiatric disorder (n = 241) and one study reported catatonia associated with another medical condition, involving patients with N-methyl-d-aspartate receptor antibody encephalitis (n = 23). Findings varied across disorders, with hyperactivity observed in areas like the prefrontal cortex (PFC), the supplementary motor area (SMA) and the ventral pre-motor cortex in acute catatonia associated to a psychiatric disorder, hypoactivity in PFC, the parietal cortex, and the SMA in catatonia associated to a medical condition, and mixed metabolic activity in the study on catatonia linked to a medical condition.
CONCLUSION
Findings support the theory of dysfunction in cortico-striatal-thalamic, cortico-cerebellar, anterior cingulate-medial orbitofrontal, and lateral orbitofrontal networks in catatonia. However, the majority of the literature focuses on schizophrenia spectrum disorders, leaving the pathophysiologic characteristics of catatonia in other disorders less understood. This review highlights the need for further research to elucidate the pathophysiology of catatonia across various disorders.
Topics: Humans; Catatonia; Schizophrenia; Syndrome; Functional Neuroimaging
PubMed: 38484496
DOI: 10.1016/j.jpsychores.2024.111640 -
Journal of Sport and Health Science Jul 2024Near-infrared spectroscopy (NIRS) technology has allowed for the measurement of cerebral and skeletal muscle oxygenation simultaneously during exercise. Since this... (Review)
Review
BACKGROUND
Near-infrared spectroscopy (NIRS) technology has allowed for the measurement of cerebral and skeletal muscle oxygenation simultaneously during exercise. Since this technology has been growing and is now successfully used in laboratory and sports settings, this systematic review aimed to synthesize the evidence and enhance an integrative understanding of blood flow adjustments and oxygen (O) changes (i.e., the balance between O delivery and O consumption) within the cerebral and muscle systems during exercise.
METHODS
A systematic review was conducted using PubMed, Embase, Scopus, and Web of Science databases to search for relevant studies that simultaneously investigated cerebral and muscle hemodynamic changes using the near-infrared spectroscopy system during exercise. This review considered manuscripts written in English and available before February 9, 2023. Each step of screening involved evaluation by 2 independent authors, with disagreements resolved by a third author. The Joanna Briggs Institute Critical Appraisal Checklist was used to assess the methodological quality of the studies.
RESULTS
Twenty studies were included, of which 80% had good methodological quality, and involved 290 young or middle-aged adults. Different types of exercises were used to assess cerebral and muscle hemodynamic changes, such as cycling (n = 11), treadmill (n = 1), knee extension (n = 5), isometric contraction of biceps brachii (n = 3), and duet swim routines (n = 1). The cerebral hemodynamics analysis was focused on the frontal cortex (n = 20), while in the muscle, the analysis involved vastus lateralis (n = 18), gastrocnemius (n = 3), biceps brachii (n = 5), deltoid (n = 1), and intercostal muscle (n = 1). Overall, muscle deoxygenation increases during exercise, reaching a plateau in voluntary exhaustion, while in the brain, oxyhemoglobin concentration increases with exercise intensity, reaching a plateau or declining at the exhaustion point.
CONCLUSION
Muscle and cerebral oxygenation respond differently to exercise, with muscle increasing O utilization and cerebral tissue increasing O delivery during exercise. However, at the exhaustion point, both muscle and cerebral oxygenation become compromised. This is characterized by a reduction in blood flow and a decrease in O extraction in the muscle, while in the brain, oxygenation reaches a plateau or decline, potentially resulting in motor failure during exercise.
Topics: Humans; Muscle, Skeletal; Oxygen Consumption; Spectroscopy, Near-Infrared; Exercise; Brain; Hemodynamics; Oxygen; Cerebrovascular Circulation; Adult
PubMed: 38462172
DOI: 10.1016/j.jshs.2024.03.003 -
Pain Reports Apr 2024Homeostatic plasticity (HP) is a negative feedback mechanism that prevents excessive facilitation or depression of cortical excitability (CE). Cortical HP responses in... (Review)
Review
Homeostatic plasticity (HP) is a negative feedback mechanism that prevents excessive facilitation or depression of cortical excitability (CE). Cortical HP responses in humans have been investigated by using 2 blocks of noninvasive brain stimulation with a no-stimulation block in between. A healthy HP response is characterized by reduced CE after 2 excitatory stimulation blocks and increased CE when using inhibitory stimulation. Conversely, impaired HP responses have been demonstrated in experimental and chronic pain conditions. Therefore, this systematic review aimed to provide an overview of the effect of pain on cortical HP in humans. Scopus, Embase, and PubMed were searched from inception until November 20, 2023. The included studies (1) compared experimental or clinical pain conditions with healthy controls, (2) induced HP using 2 blocks of stimulation with a no-stimulation interval, and (3) evaluated CE measures such as motor-evoked potentials. Four studies were included, consisting of 5 experiments and 146 participants, of whom 63 were patients with chronic pain and 48 were subjected to an experimental pain model. This systematic review found support for an HP impairment in pain compared with that in pain-free states, reflected by a lack of CE reduction after excitatory-excitatory HP induction over the primary motor cortex. Inhibitory-inhibitory HP induction did not produce a consistent HP response across studies, independent of pain or pain-free states. Standardization of HP induction protocols and outcome calculations is needed to ensure reproducibility and study comparison. Future HP studies may consider investigating sensory domains including nociception, which would further our understanding of abnormal HP regulation in pain conditions.
PubMed: 38444774
DOI: 10.1097/PR9.0000000000001141 -
Journal of Neuroengineering and... Mar 2024The regulation of gait is critical to many activities of everyday life. When walking, somatosensory information obtained from mechanoreceptors throughout body is... (Review)
Review
BACKGROUND
The regulation of gait is critical to many activities of everyday life. When walking, somatosensory information obtained from mechanoreceptors throughout body is delivered to numerous supraspinal networks and used to execute the appropriate motion to meet ever-changing environmental and task demands. Aging and age-related conditions oftentimes alter the supraspinal sensorimotor control of walking, including the responsiveness of the cortical brain regions to the sensorimotor inputs obtained from the peripheral nervous system, resulting in diminished mobility in the older adult population. It is thus important to explicitly characterize such supraspinal sensorimotor elements of walking, providing knowledge informing novel rehabilitative targets. The past efforts majorly relied upon mental imagery or virtual reality to study the supraspinal control of walking. Recent efforts have been made to develop magnetic resonance imaging (MRI)-compatible devices simulating specific somatosensory and/or motor aspects of walking. However, there exists large variance in the design and functionality of these devices, and as such inconsistent functional MRI (fMRI) observations.
METHODS
We have therefore completed a systematic review to summarize current achievements in the development of these MRI-compatible devices and synthesize available imaging results emanating from studies that have utilized these devices.
RESULTS
The device design, study protocol and neuroimaging observations of 26 studies using 13 types of devices were extracted. Three of these devices can provide somatosensory stimuli, eight motor stimuli, and two both types of stimuli. Our review demonstrated that using these devices, fMRI data of brain activation can be successfully obtained when participants remain motionless and experience sensorimotor stimulation during fMRI acquisition. The activation in multiple cortical (e.g., primary sensorimotor cortex) and subcortical (e.g., cerebellum) regions has been each linked to these types of walking-related sensorimotor stimuli.
CONCLUSION
The observations of these publications suggest the promise of implementing these devices to characterize the supraspinal sensorimotor control of walking. Still, the evidence level of these neuroimaging observations was still low due to small sample size and varied study protocols, which thus needs to be confirmed via studies with more rigorous design.
Topics: Humans; Aged; Walking; Magnetic Resonance Imaging; Gait; Neuroimaging; Aging
PubMed: 38443983
DOI: 10.1186/s12984-024-01323-y -
Translational Neuroscience Jan 2023Attention deficit hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders diagnosed in childhood. Two common features of ADHD are impaired...
Attention deficit hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders diagnosed in childhood. Two common features of ADHD are impaired behavioural inhibition and sustained attention. The Go/No-Go experimental paradigm with concurrent functional magnetic resonance imaging (fMRI) scanning has previously revealed important neurobiological correlates of ADHD such as the supplementary motor area and the prefrontal cortex. The coordinate-based meta-analysis combined with quantitative techniques, such as activation likelihood estimate (ALE) generation, provides an unbiased and objective method of summarising these data to understand the brain network architecture and connectivity in ADHD children. Go/No-Go task-based fMRI studies involving children and adolescent subjects were selected. Coordinates indicating foci of activation were collected to generate ALEs using threshold values (voxel-level: < 0.001; cluster-level: < 0.05). ALEs were matched to one of seven canonical brain networks based on the cortical parcellation scheme derived from the Human Connectome Project. Fourteen studies involving 457 children met the eligibility criteria. No significant convergence of Go/No-Go related brain activation was found for ADHD groups. Three significant ALE clusters were detected for brain activation relating to controls or ADHD < controls. Significant clusters were related to specific areas of the default mode network (DMN). Network-based analysis revealed less extensive DMN, dorsal attention network, and limbic network activation in ADHD children compared to controls. The presence of significant ALE clusters may be due to reduced homogeneity in the selected sample demographic and experimental paradigm. Further investigations regarding hemispheric asymmetry in ADHD subjects would be beneficial.
PubMed: 38410259
DOI: 10.1515/tnsci-2022-0299 -
Neurophysiologie Clinique = Clinical... Feb 2024To update a systematic review of the efficacy and safety of transcranial direct current stimulation (tDCS) for analgesia, for antidepressant effects, and to reduce the... (Meta-Analysis)
Meta-Analysis
OBJECTIVES
To update a systematic review of the efficacy and safety of transcranial direct current stimulation (tDCS) for analgesia, for antidepressant effects, and to reduce the impact of fibromyalgia (FM), looking for optimal areas of stimulation.
METHODS
We searched five databases to identify randomized controlled trials comparing active and sham tDCS for FM. The primary outcome was pain intensity, and secondary outcome measures included FM Impact Questionnaire (FIQ) and depression score. Meta-analysis was conducted using standardized mean difference (SMD). Subgroup analysis was performed to determine the effects of different regional stimulation, over the primary motor cortex (M1), dorsolateral prefrontal cortex (DLPFC), opercular-insular cortex (OIC), and occipital nerve (ON) regions. We analyzed the minimal clinically important difference (MCID) by the value of the mean difference (MD) for an 11-point scale for pain, the Beck Depressive Inventory-II (BDI-II), and the Fibromyalgia Impact Questionnaire (FIQ) score. We described the certainty of the evidence (COE) using the tool GRADE profile.
RESULTS
Twenty studies were included in the analysis. Active tDCS had a positive effect on pain (SMD= -1.04; 95 % CI -1.38 to -0.69), depression (SMD= -0.46; 95 % CI -0.64 to -0.29), FIQ (SMD= -0.73; 95 % CI -1.09 to -0.36), COE is moderate. Only group M1 (SD=-1.57) and DLPFC (SD=-1.44) could achieve MCID for analgesia; For BDI-II, only group DLPFC (SD=-5.36) could achieve an MCID change. Adverse events were mild.
CONCLUSION
tDCS is a safe intervention that relieves pain intensity, reduces depression, and reduces the impact of FM on life. Achieving an MCID is related to the stimulation site and the target symptom.
Topics: Humans; Fibromyalgia; Pain; Pain Management; Transcranial Direct Current Stimulation
PubMed: 38387108
DOI: 10.1016/j.neucli.2024.102944 -
General Hospital Psychiatry 2024Several types of neuromodulation have been investigated for the treatment of fibromyalgia, but they show varied efficacy on pain, functioning, comorbid depression and... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
Several types of neuromodulation have been investigated for the treatment of fibromyalgia, but they show varied efficacy on pain, functioning, comorbid depression and comorbid anxiety. Whether some types of neuromodulation or some factors are associated with a better response also awaits clarification.
METHODS
We conducted a systematic review and network meta-analysis of randomized controlled trials to evaluate the efficacy of neuromodulation in patients with fibromyalgia. We searched PubMed, EMBASE, the Cochrane Central Register of Controlled Trials and PsycINFO before March 2022. We employed a frequentist random-effects network meta-analysis.
RESULTS
Forty trials involving 1541 participants were included. Compared with sham control interventions, several types of transcranial direct current stimulation (tDCS), transcranial random noise stimulation (tRNS), and high-frequency repetitive transcranial magnetic stimulation (rTMS) were associated with significant reduction of pain, depression, anxiety, and improvement in functioning. Many significantly effective treatment options involve stimulation of the primary motor cortex or dorsolateral prefrontal cortex.
CONCLUSION
We concluded that several types of rTMS, tDCS and tRNS may have the potential to be applied for clinical purposes.
Topics: Humans; Fibromyalgia; Transcranial Direct Current Stimulation; Network Meta-Analysis; Transcranial Magnetic Stimulation; Pain; Treatment Outcome
PubMed: 38382420
DOI: 10.1016/j.genhosppsych.2024.01.007 -
Journal of Psychiatry & Neuroscience :... 2024Transcranial magnetic stimulation (TMS) is a noninvasive neurostimulation modality that has been used to study human synaptic plasticity. Leveraging work in ex vivo...
BACKGROUND
Transcranial magnetic stimulation (TMS) is a noninvasive neurostimulation modality that has been used to study human synaptic plasticity. Leveraging work in ex vivo preparations, mechanistically informed pharmacological adjuncts to TMS have been used to improve our fundamental understanding of TMS-induced synaptic plasticity.
METHODS
We systematically reviewed the literature pairing pharmacological adjuncts with TMS plasticity-induction protocols in humans. We searched MEDLINE, PsycINFO, and Embase from 2013 to Mar. 10, 2023. Studies published before 2013 were extracted from a previous systematic review. We included studies using repetitive TMS, theta-burst stimulation, paired associative stimulation, and quadripulse stimulation paradigms in healthy and clinical populations.
RESULTS
Thirty-six studies met our inclusion criteria (28 in healthy and 8 in clinical populations). Most pharmacological agents have targeted the glutamatergic -methyl-d-aspartate (NMDA; 15 studies) or dopamine receptors (13 studies). The NMDA receptor is necessary for TMS-induced plasticity; however, sufficiency has not been shown across protocols. Dopaminergic modulation of TMS-induced plasticity appears to be dose-dependent. The GABAergic, cholinergic, noradrenergic, and serotonergic neurotransmitter systems have small evidence bases supporting modulation of TMS-induced plasticity, as do voltage-gated calcium and sodium channels. Studies in clinical populations suggest that pharmacological adjuncts to TMS may rescue motor cortex plasticity, with implications for therapeutic applications of TMS and a promising clinical trial in depression.
LIMITATIONS
This review is limited by the predominance in the literature of studies with small sample sizes and crossover designs.
CONCLUSION
Pharmacologically enhanced TMS largely parallels findings from ex vivo preparations. As this area expands and novel targets are tested, adequately powered samples in healthy and clinical populations will inform the mechanisms of TMS-induced plasticity in health and disease.
Topics: Humans; Transcranial Magnetic Stimulation; Neuronal Plasticity; Motor Cortex; Dopamine; Calcium; Evoked Potentials, Motor
PubMed: 38359933
DOI: 10.1503/jpn.230090 -
Somatosensory & Motor Research Feb 2024Transcranial direct current stimulation (tDCS) is widely used in motor recovery. Nevertheless, whether tDCS improves motor learning in healthy older adults is still...
BACKGROUND
Transcranial direct current stimulation (tDCS) is widely used in motor recovery. Nevertheless, whether tDCS improves motor learning in healthy older adults is still controversial. This review aims to investigate the effectiveness of tDCS on motor learning in healthy elderly individuals.
METHODS
The PubMed, Cochrane Library, Web of Science and Embase databases were initially searched from inception to December 5, 2022. The standard mean difference (SMD) with the corresponding 95% confidence intervals (CIs) were analysed random-effect models.
RESULTS
Compared with the sham group, no significant effects were found regarding improvement in motor learning based on the speed or accuracy of the task and reaction time for the tDCS intervention group. After subgroup analysis, a significant effect was found for improved motor learning based on reaction time in the primary motor cortex (M1)-cerebellar group.
CONCLUSIONS
This review revealed that tDCS had no significant effect on improving the speed or accuracy of motor learning in healthy elderly adults. However, it has a significant effect on improving the motor learning ability based on the reaction time of the task (mainly referring to the tDCS stimulation position of M1 and cerebellar), although the results have obvious heterogeneity and uncertainty.
PubMed: 38319133
DOI: 10.1080/08990220.2024.2310851 -
Epilepsy & Behavior : E&B Mar 2024The term 'functional/dissociative seizures (FDS)' refers to a paroxysmal, transient clinical manifestation that may include motor, sensory, vegetative, psychological and... (Review)
Review
INTRODUCTION
The term 'functional/dissociative seizures (FDS)' refers to a paroxysmal, transient clinical manifestation that may include motor, sensory, vegetative, psychological and cognitive signs, similar to the manifestations observed in epileptic seizures. In recent years, there has been an increase of literature in the field of brain imaging research on functional neurological disorders and, more specifically, on FDS. However, most of the studies have been carried out on limited samples. We propose an update of this review work by performing a systematic review of studies performed since 2017 in the field of neuroimaging in patients with FDS.
METHODS
We conducted a systematic review of the literature using the PRISMA methodology and reproduced most of the methodological elements of the latest systematic literature review.
RESULTS
Our work over the last five years has identified 14 articles. It is still difficult to isolate a distinct structure or network specifically involved in the mechanism of FDS. However, certain structures are recurrently involved in imaging studies, notably the amygdala, the orbitofrontal cortex, and the anterior cingulate cortex.
CONCLUSION
The contribution of neuroimaging may allow a more precise explanation of the disorder for patients, avoiding the stigma frequently associated with this diagnosis. as with other 'conversion' phenomena which have traditionally been considered only as 'medically unexplained'. In the longer term and beyond a better understanding of the physiopathology of the disorder, the challenge of this neuroimaging work would be to identify specific imaging biomarkers for a diagnosis of FDS.
Topics: Humans; Psychogenic Nonepileptic Seizures; Conversion Disorder; Dissociative Disorders; Seizures; Epilepsy
PubMed: 38281393
DOI: 10.1016/j.yebeh.2024.109654