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Journal of Neuroengineering and... Jun 2024Repeated transcranial magnetic stimulation (rTMS) could induce alterations in cortical excitability and promote neuroplasticity. To precisely quantify these effects,... (Meta-Analysis)
Meta-Analysis Review
Impact of repetitive transcranial magnetic stimulation on cortical activity: a systematic review and meta-analysis utilizing functional near-infrared spectroscopy evaluation.
BACKGROUND
Repeated transcranial magnetic stimulation (rTMS) could induce alterations in cortical excitability and promote neuroplasticity. To precisely quantify these effects, functional near-infrared spectroscopy (fNIRS), an optical neuroimaging modality adept at detecting changes in cortical hemodynamic responses, has been employed concurrently alongside rTMS to measure and tailor the impact of diverse rTMS protocols on the brain cortex.
OBJECTIVE
This systematic review and meta-analysis aimed to elucidate the effects of rTMS on cortical hemodynamic responses over the primary motor cortex (M1) as detected by fNIRS.
METHODS
Original articles that utilized rTMS to stimulate the M1 cortex in combination with fNIRS for the assessment of cortical activity were systematically searched across the PubMed, Embase, and Scopus databases. The search encompassed records from the inception of these databases up until April, 2024. The assessment for risk of bias was also conducted. A meta-analysis was also conducted in studies with extractable raw data.
RESULTS
Among 312 studies, 14 articles were eligible for qualitative review. 7 studies were eligible for meta-analysis. A variety of rTMS protocols was employed on M1 cortex. In inhibitory rTMS, multiple studies observed a reduction in the concentration of oxygenated hemoglobin [HbO] at the ipsilateral M1, contrasted by an elevation at the contralateral M1. Meta-analysis also corroborated this consistent trend. Nevertheless, certain investigations unveiled diminished [HbO] in bilateral M1. Several studies also depicted intricate inhibitory or excitatory interplay among distinct cortical regions.
CONCLUSION
Diverse rTMS protocols led to varied patterns of cortical activity detected by fNIRS. Meta-analysis revealed a trend of increasing [HbO] in the contralateral cortices and decreasing [HbO] in the ipsilateral cortices following low frequency inhibitory rTMS. However, due to the heterogeneity between studies, further research is necessary to comprehensively understand rTMS-induced alterations in brain activity.
Topics: Transcranial Magnetic Stimulation; Spectroscopy, Near-Infrared; Humans; Motor Cortex
PubMed: 38915003
DOI: 10.1186/s12984-024-01407-9 -
Neurologia I Neurochirurgia Polska 2024Drug-resistant epilepsy (DRE) remains poorly-controlled in c.33% of patients, and up to 50% of patients suffering from DRE are deemed not to be suitable candidates for... (Review)
Review
INTRODUCTION
Drug-resistant epilepsy (DRE) remains poorly-controlled in c.33% of patients, and up to 50% of patients suffering from DRE are deemed not to be suitable candidates for resective surgery. For these patients, deep brain stimulation (DBS) may constitute the last resort in the treatment of DRE.
STATE OF THE ART
We undertook a systematic review of the current literature on DBS efficacy and the safety of two thalamic nuclei-anterior nucleus of the thalamus (ANT) and the centromedian nucleus of the thalamus in the management of patients with DRE. A search using two electronic databases, the Medical Literature, Analysis, and Retrieval System on-line (MEDLINE) and the Cochrane Central Register of Controlled Trials (CEN-TRAL) was conducted.
CLINICAL IMPLICATIONS
We found 30 articles related to ANT DBS and 13 articles related to CMN DBS which were further analysed. Based on the clinical research articles, we found a mean seizure frequency reduction for both thalamic nuclei. For ANT DBS, the mean seizure frequency reduction ranged from 48% to 75%, and for CMN DBS from 46.7% to 91%. The responder rate (defined as at least 50% reduction in seizure frequency) was reported to be 53.2-75% for patients after ANT DBS and 50-90% for patients after CMN DBS.
FUTURE DIRECTIONS
ANT and CMN DBS appear to be safe and efficacious treatments, particularly in patients with refractory partial seizures and primary generalised seizures. ANT DBS reduces most effectively seizures originating in the temporal and frontal lobes. CMN DBS reduces mostly primary generalised tonic-clonic and atypical absences and atonic seizures. Seizures related to Lennox-Gastaut syndrome respond very favourably to CMN DBS.
Topics: Humans; Deep Brain Stimulation; Drug Resistant Epilepsy; Anterior Thalamic Nuclei; Intralaminar Thalamic Nuclei; Treatment Outcome
PubMed: 38864766
DOI: 10.5603/pjnns.98258 -
Psychiatry Research Aug 2024The depression response trajectory after a course of repetitive transcranial magnetic stimulation(rTMS) remains understudied. We searched for blinded randomized... (Meta-Analysis)
Meta-Analysis Review
The depression response trajectory after a course of repetitive transcranial magnetic stimulation(rTMS) remains understudied. We searched for blinded randomized controlled trials(RCTs) that examined conventional rTMS over left dorsolateral prefrontal cortex(DLPFC) for major depressive episodes(MDE). The effect size was calculated as the difference in depression improvement, between active and sham rTMS. We conducted a random-effects dose-response meta-analysis to model the response trajectory from the beginning of rTMS to the post-treatment follow-up phase. The area under curve (AUC) of the first 8-week response trajectory was calculated to compare antidepressant efficacy between different rTMS protocols. We included 40 RCTs(n = 2012). The best-fitting trajectory model exhibited a logarithmic curve(X=17.7, P < 0.001), showing a gradual ascent with tapering off around the 3-4th week mark and maintaining until week 16. The maximum effect size was 6.1(95 %CI: 1.25-10.96) at week 16. The subgroup analyses showed distinct trajectories across different rTMS protocols. Besides, the comparisons of AUC showed that conventional rTMS protocols with more pulse/session group or more total pulses were associated with greater efficacy than those with fewer pulse/session or fewer total pulses, respectively. A course of conventional left DLPFC rTMS could lead to both acute antidepressant effects and sustained after-effects, which were modeled by different rTMS protocols in MDE.
Topics: Humans; Depressive Disorder, Major; Transcranial Magnetic Stimulation; Dorsolateral Prefrontal Cortex; Prefrontal Cortex; Randomized Controlled Trials as Topic
PubMed: 38850891
DOI: 10.1016/j.psychres.2024.115979 -
Gynecological Endocrinology : the... Dec 2024To analyze differences in the menstrual pattern, age at menarche, and body mass index (BMI) in adolescents with Hypothalamic-Pituitary-Ovarian (HPO) axis immaturity and... (Meta-Analysis)
Meta-Analysis
OBJECTIVE
To analyze differences in the menstrual pattern, age at menarche, and body mass index (BMI) in adolescents with Hypothalamic-Pituitary-Ovarian (HPO) axis immaturity and Polycystic Ovary Syndrome (PCOS) through a systematic review and meta-analysis.
METHODS
The PubMed, EMBASE, Web of Science, Virtual Health Library, Scopus databases were searched using combinations of descriptors. Study quality was assessed using the Newcastle-Ottawa Scale. For data analysis, the results were grouped into PCOS group and NPCOS group (HPO axis immaturity). We performed a meta-analysis of raw data and the inverse variance method, employing the standardized mean difference, of the age at menarche and BMI of adolescents.
RESULTS
Participants totaled 1,718 from nine selected studies. The meta-analysis showed that the PCOS group had a higher BMI than the NPCOS group (SMD 0.334; CI95% 0.073 - 0.595; = .012). The degree of heterogeneity of the studies was approximately 40%. No significant difference in age at menarche (SMD - 0.027; CI95% -0.227 - 0.172; = 0.790) and menstrual patterns was found, but amenorrhea was described only in adolescents with PCOS.
CONCLUSIONS
The main characteristic in menstrual pattern that differentiated PCOS patients from girls with HPO axis immaturity was amenorrhea. Also, the BMI of PCOS patients was nearly one third higher than that of adolescents with HPO axis immaturity.
Topics: Humans; Polycystic Ovary Syndrome; Female; Adolescent; Menarche; Hypothalamo-Hypophyseal System; Body Mass Index; Ovary; Menstrual Cycle
PubMed: 38818646
DOI: 10.1080/09513590.2024.2360077 -
Neurology Jun 2024Parietal lobe epilepsy (PLE) surgery can be an effective treatment for selected patients with intractable epilepsy but can be associated with the risk of serious...
BACKGROUND AND OBJECTIVES
Parietal lobe epilepsy (PLE) surgery can be an effective treatment for selected patients with intractable epilepsy but can be associated with the risk of serious neurologic deficits. We performed a systematic review of the literature to obtain a comprehensive summary of the frequency and types of new postoperative neurologic deficits in patients undergoing PLE resective surgery.
METHODS
We searched MEDLINE, Embase, and Cochrane Central Register of Controlled Trials for articles published between January 1, 1990, and April 28, 2022. We included studies that reported postoperative neurologic outcome following PLE resective surgery confined to the parietal lobe. We required that studies included ≥5 patients. The data collected included demographic information and specific details of postoperative neurologic deficits. When available, individual patient data were collected. We used the Risk of Bias in Nonrandomized Studies of Interventions tool to assess the risk of bias and Grading of Recommendations Assessment, Development, and Evaluation to assess the quality of the evidence.
RESULTS
Of the 3,461 articles screened, 33 studies met the inclusion criteria. A total of 370 patients were included. One hundred patients (27.0%) had a new deficit noted postoperatively. Approximately half of the patients with deficits experienced only transient deficits. Motor deficits were the most commonly identified deficit. The rates of motor deficits noted after PLE surgery were 5.7%, 3.2%, and 2.2% for transient, long-term, and duration not specified, respectively. Sensory and visual field deficits were also commonly reported. Gerstmann syndrome was noted postoperatively in 4.9% of patients and was almost always transient. Individual patient data added information on parietal lobe subregion postoperative neurologic outcome.
DISCUSSION
Our systematic review provides a comprehensive summary of the frequency and types of neurologic deficits associated with PLE surgery. A significant percentage of postoperative deficits are transient. In addition to the expected sensory and visual deficits, PLE surgery is associated with a notable risk of motor deficits. The available literature has important deficiencies. Our study highlights gaps in the literature and provides recommendations for future directions.
TRIAL REGISTRATION INFORMATION
This systematic review was registered on PROSPERO (CRD42022313108, May 26, 2022).
Topics: Humans; Parietal Lobe; Postoperative Complications; Neurosurgical Procedures; Drug Resistant Epilepsy; Treatment Outcome; Epilepsies, Partial
PubMed: 38815235
DOI: 10.1212/WNL.0000000000209322 -
Neuroscience and Biobehavioral Reviews Jul 2024Stress is known to impair reproduction through interactions between the hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-gonadal (HPG) axes. However,...
Stress is known to impair reproduction through interactions between the hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-gonadal (HPG) axes. However, while it is well accepted that stress can alter estrous cycle regularity, a key indicator of female's HPG axis function, effects of different types of psychological stress have been inconsistent. This systematic review evaluated the impact of rodent models of psychological stress on estrous cyclicity, while reporting biological parameters pertaining to HPA or HPG axis function assessed within these studies. We performed a systematic database search and included articles that implemented a psychological stress model in rodents and reported estrous cyclicity for at least two cycles after initiation of stress. Of the 32 studies included, 62.5% reported post-stress alterations to estrous cyclicity, with Chronic Mild Stress (CMS) models showing the most conclusive effects. Twenty-five studies measured HPG or HPA axis markers, with cycle disruptions being commonly observed in parallel with altered estradiol and increased corticosterone levels. Our review highlights gaps in reporting estrous cyclicity assessments and makes recommendations to improve comparability between studies.
Topics: Animals; Female; Disease Models, Animal; Estrous Cycle; Hypothalamo-Hypophyseal System; Pituitary-Adrenal System; Rodentia; Stress, Psychological
PubMed: 38763179
DOI: 10.1016/j.neubiorev.2024.105730 -
Clinical Neurology and Neurosurgery Jul 2024Seizure disorders have often been found to be associated with corpus callosum injuries, but in most cases, they remain undiagnosed. Understanding the clinical,...
INTRODUCTION
Seizure disorders have often been found to be associated with corpus callosum injuries, but in most cases, they remain undiagnosed. Understanding the clinical, electrographic, and neuroradiological alternations can be crucial in delineating this entity.
OBJECTIVE
This systematic review aims to analyze the effects of corpus callosum injuries on seizure semiology, providing insights into the neuroscientific and clinical implications of such injuries.
METHODS
Adhering to the PRISMA guidelines, a comprehensive search across multiple databases, including PubMed/Medline, NIH, Embase, Cochrane Library, and Cross-ref, was conducted until September 25, 2023. Studies on seizures associated with corpus callosum injuries, excluding other cortical or sub-cortical involvements, were included. Machine learning (Random Forest) and deep learning (1D-CNN) algorithms were employed for data classification.
RESULTS
Initially, 1250 articles were identified from the mentioned databases, and additional 350 were found through other relevant sources. Out of all these articles, 41 studies met the inclusion criteria, collectively encompassing 56 patients The most frequent clinical manifestations included generalized tonic-clonic seizures, complex partial seizures, and focal seizures. The most common callosal injuries were related to reversible splenial lesion syndrome and cytotoxic lesions. Machine learning and deep learning analyses revealed significant correlations between seizure types, semiological parameters, and callosal injury locations. Complete recovery was reported in the majority of patients post-treatment.
CONCLUSION
Corpus callosum injuries have diverse impacts on seizure semiology. This review highlights the importance of understanding the role of the corpus callosum in seizure propagation and manifestation. The findings emphasize the need for targeted diagnostic and therapeutic strategies in managing seizures associated with callosal injuries. Future research should focus on expanding the data pool and exploring the underlying mechanisms in greater detail.
Topics: Humans; Corpus Callosum; Seizures; Machine Learning; Brain Injuries
PubMed: 38762973
DOI: 10.1016/j.clineuro.2024.108316 -
Neuroscience and Biobehavioral Reviews Jul 2024This review synthesises individual differences in neural processes related to emotion regulation (ER). It comprises individual differences in self-reported and... (Review)
Review
This review synthesises individual differences in neural processes related to emotion regulation (ER). It comprises individual differences in self-reported and physiological regulation success, self-reported ER-related traits, and demographic variables, to assess their correlation with brain activation during ER tasks. Considering region-of-interest (ROI) and whole-brain analyses, the review incorporated data from 52 functional magnetic resonance imaging studies. Results can be summarized as follows: (1) Self-reported regulation success (assessed by emotional state ratings after regulation) and self-reported ER-related traits (assessed by questionnaires) correlated with brain activity in the lateral prefrontal cortex. (2) Amygdala activation correlated with ER-related traits only in ROI analyses, while it was associated with regulation success in whole-brain analyses. (3) For demographic and physiological measures, there was no systematic overlap in effects reported across studies. In showing that individual differences in regulation success and ER-related traits can be traced back to differences in the neural activity of brain regions associated with emotional reactivity (amygdala) and cognitive control (lateral prefrontal cortex), our findings can inform prospective personalised intervention models.
Topics: Humans; Individuality; Emotional Regulation; Brain; Magnetic Resonance Imaging; Amygdala; Emotions; Brain Mapping; Prefrontal Cortex
PubMed: 38759742
DOI: 10.1016/j.neubiorev.2024.105727 -
Neuroscience and Biobehavioral Reviews Jul 2024This study aimed to evaluate the association of the six parameters, namely stimulation intensity, stimulation frequency, pulses per session, treatment duration, number... (Meta-Analysis)
Meta-Analysis Review
This study aimed to evaluate the association of the six parameters, namely stimulation intensity, stimulation frequency, pulses per session, treatment duration, number of sessions, and total number of pulses with the efficacy of conventional transcranial magnetic stimulation (rTMS) over left dorsolateral prefrontal cortex for patients with treatment-resistant depression (TRD). A random-effects dose-response meta-analysis of blinded randomized controlled trials (RCTs) involving 2391 participants were conducted to examine the dose-effect relationship of six stimulation parameters. Any of the six parameters significantly individually predicted proportion of variance in efficacy: pulses per session (R²=52.7%), treatment duration (R²=51.2%), total sessions (R²=50.9%), frequency (R²=49.6%), total pulses (R²=49.5%), and intensity (R²= 40.4%). Besides, we identified frequency as a potential parameter interacting with the other five parameters, resulting in a significant increase in variance(ΔR) ranging from 5.0% to 16.7%. Finally, we found that RCTs using frequency > 10 Hz compared to those of 10 Hz showed better dose-effect relationships. We conclude that the six stimulation parameters significantly predict the dose-effect relationship of conventional rTMS on TRD. Besides, higher stimulation frequency, higher stimulation intensity, and adequate number of pulses were associated with treatment efficacy.
Topics: Humans; Transcranial Magnetic Stimulation; Depressive Disorder, Treatment-Resistant; Dorsolateral Prefrontal Cortex
PubMed: 38723735
DOI: 10.1016/j.neubiorev.2024.105704 -
Neuroscience and Biobehavioral Reviews Jul 2024Human brain activity consists of different frequency bands associated with varying functions. Oscillatory activity of frontal brain regions in the theta range (4-8 Hz)... (Meta-Analysis)
Meta-Analysis Review
Human brain activity consists of different frequency bands associated with varying functions. Oscillatory activity of frontal brain regions in the theta range (4-8 Hz) is linked to cognitive processing and can be modulated by neurofeedback - a technique where participants receive real-time feedback about their brain activity and learn to modulate it. However, criticism of this technique evolved, and high heterogeneity of study designs complicates a valid evaluation of its effectiveness. This meta-analysis provides the first systematic overview over studies attempting to modulate frontal midline theta with neurofeedback in healthy human participants. Out of 1261 articles screened, 14 studies were eligible for systematic review and 11 for quantitative meta-analyses. Studies were evaluated following the DIAD model and the PRISMA guidelines. A significant across-study effect of medium size (Hedges' g = .66; 95%-CI [-0.62, 1.73]) with substantial between-study heterogeneity (Q(16) = 167.43, p < .001) was observed and subanalysis revealed effective frontal midline theta upregulation. We discuss moderators of effect sizes and provide guidelines for future research in this dynamic field.
Topics: Humans; Theta Rhythm; Neurofeedback; Frontal Lobe
PubMed: 38723734
DOI: 10.1016/j.neubiorev.2024.105696