Changes In Functional Activity Research Articles

Machine learning-optimized non-invasive brain stimulation and treatment response classification for major depression

Background/ObjectivesTranscranial direct current stimulation (tDCS) is a non-invasive brain stimulation intervention that shows promise as a potential treatment for depression. However, the clinical efficacy of tDCS varies, possibly due to individual differences in head anatomy affecting tDCS dosage. While functional changes in brain activity are more commonly reported in major depressive disorder (MDD), some studies suggest that subtle macroscopic structural differences, such as cortical thickness or brain volume reductions, may occur in MDD and could influence tDCS electric field (E-field) distributions. Therefore, accounting for individual anatomical differences may provide a pathway to optimize functional gains in MDD by formulating personalized tDCS dosage.MethodsTo address the dosing variability of tDCS, we examined a subsample of sixteen active-tDCS participants’ data from the larger ELECT clinical trial (NCT01894815). With this dataset, individualized neuroimaging-derived computational models of tDCS current were generated for (1) classifying treatment response, (2) elucidating essential stimulation features associated with treatment response, and (3) computing a personalized dose of tDCS to maximize the likelihood of treatment response in MDD.ResultsIn the ELECT trial, tDCS was superior to placebo (3.2 points [95% CI, 0.7 to 5.5; P = 0.01]). Our algorithm achieved over 90% overall accuracy in classifying treatment responders from the active-tDCS group (AUC = 0.90, F1 = 0.92, MCC = 0.79). Computed precision doses also achieved an average response likelihood of 99.981% and decreased dosing variability by 91.9%.ConclusionThese findings support our previously developed precision-dosing method for a new application in psychiatry by optimizing the statistical likelihood of tDCS treatment response in MDD.

Aberrant dynamic functional and effective connectivity changes of the primary visual cortex in patients with retinal detachment via machine learning.

Previous neuroimaging studies have identified significant alterations in brain functional activity in retinal detachment (RD) patients, these investigations predominantly concentrated on local functional activity changes. The potential directional alterations in functional connectivity within the primary visual cortex (V1) in RD patients remain to be elucidated. In this study, we employed seed-based functional connectivity analysis along with Granger causality analysis to examine the directional alterations in dynamic functional connectivity (dFC) within the V1 region of patients diagnosed with RD. Finally, a support vector machine algorithm was utilized to classify patients with RD and healthy controls (HCs). RD patients exhibited heightened dynamic functional connectivity (dFC) and dynamic effective connectivity (dEC) between the Visual Network (VN) and default mode network (DMN), as well as within the VN, compared to HCs. Conversely, dFC between VN and auditory network (AN) decreased, and dEC between VN and sensorimotor network (SMN) significantly reduced. In state 4, RD patients had higher frequency. Notably, variations in dFC originating from the left V1 region proved diagnostically effective, achieving an AUC of 0.786. This study reveals significant alterations in the connectivity between the VN and the default mode network in patients with RD. These changes may disrupt visual information processing and higher cognitive integration in RD patients. Additionally, alterations in the left V1 region and whole-brain dFC show promising potential in aiding the diagnosis of RD. These findings offer valuable insights into the neural mechanisms underlying visual and cognitive impairments associated with RD.

Effects of repetitive transcranial magnetic stimulation at different targets on brain function in stroke patients: a randomized controlled trial.

Repetitive transcranial magnetic stimulation (rTMS) can improve post stroke motor function. However, there is little research on targets. The purpose of this study is to investigate the effects of rTMS therapy with different targets on post stroke motor function and neural plasticity. Fifty-four subjects were randomly divided into M1 (Primary motor area) group, SMA (supplementary motor area) group and Sham group, and were given 10 Hz on the affected M1 area, SMA area and sham stimulation rTMS. The primary outcomes included Fugl-Meyer Assessment Upper Extremity Scale (FMA-UE), Fugl-Meyer Assessment Lower Extremity Scale (FMA-LE) and Berg balance scale (BBS). Secondary outcomes: amplitude of low frequency fluctuation (ALFF), regional homogeneity (ReHo) and functional connectivity (FC) were analyzed by functional magnetic resonance imaging (fMRI) to evaluate brain functional activation and functional connectivity changes. The 2-way repeated-measures ANOVA revealed a significant group × time interaction (F = 23.494, p < 0.001; F = 10.801, p < 0.001; F = 17.812, p < 0.001) in the FMA-UE, FMA-LE and BBS scores. Post hoc analysis indicated that 4 weeks of SMA rTMS resulted in an increase in FMA-UE, FMA-LE and BBS scores compared with Sham group (p = 0.006; p = 0.033; p = 0.012), SMA group was significantly increased in BBS compared with M1 group (p = 0.034). Moreover, there were significant effects of time in all 3 groups in the FMA-UE, FMA-LE and BBS scores (p < 0.001). In addition, the increase of ALFF in the supramarginal gyrus on the affected side was correlated with better FMA-UE recovery, the increase of ALFF in the middle temporal gyrus and the middle frontal gyrus on the affected side was positively correlated with the improvement of BBS, and the ALFF in the cerebellum on the healthy side was negatively correlated with the improvement of BBS. There was a positive correlation between FC (SMA - ipsilateral cerebellum) changes and BBS changes in SMA group. In conclusion, SMA-rTMS intervention has a better recovery effect on motor dysfunction after stroke than Sham-rTMS. SMA-rTMS led to similar improvement on motor function but significantly greater improvement on balance compared to M1-rTMS, and this may pave a new way for stroke rehabilitation. Registration number: ChiCTR2200060955, https://www.chictr.org.cn/.

Neuroimaging Correlates of Post-COVID-19 Symptoms: A Functional MRI Approach

Backgrounds and Purpose: Post-COVID syndrome is characterized by persistent symptoms, including fatigue and cognitive impairment. These symptoms may be experienced by up to 80% of patients. We aimed to identify possible patterns of brain activation underlying post-COVID fatigue. Methods: The study used functional MRI (Siemens MAGNETOM Prisma 3T scanner with a specially created protocol) of the brain in 30 patients with post-COVID fatigue syndrome and 20 healthy volunteers. Task functional MRI (fMRI) was performed using a cognitive paradigm (modified Stroop test). Eligible patients included adults aged 18–50 years with a &gt;12 weeks before enrolment (less than 12 months) prior history of documented COVID-19 with symptoms of fatigue not attributable to any other cause, and with MFI-20 score &gt; 30 and MoCA at first visit. Healthy control participants had no prior history of COVID-19 and negative tests for severe acute coronavirus respiratory syndrome with MFI-20 score &lt; 30 and MoCA at first visit. Task fMRI data were processed using the SPM12 software package based on MATLAB R2022a. Results: Cognitive task fMRI analysis showed significantly higher activation in the post-COVID group versus healthy volunteers’ group. Between-group analysis showed significant activation differences. Using a threshold of T &gt; 3 we identified eight clusters of statistically significant activation: supramarginal gyri, posterior cingulate cortex, opercular parts of precentral gyri and cerebellum posterior lobe bilaterally. Conclusions: Post-COVID fatigue syndrome associated with subjective cognitive impairment could show changes in brain functional activity in the areas connected with information processing speed and quality.

The Lifespan Trajectories of Brain Activities Related to Cognitive Control.

Cognitive control plays a pivotal role in guiding human goal-directed behavior. While existing studies have documented an inverted U-shaped trajectory of cognitive control both behaviorally and anatomically, little is known about the corresponding changes in functional brain activation with age. To bridge this gap, we conducted a comprehensive meta-analysis of 129 neuroimaging studies using conflict tasks, encompassing 3,388 participants aged from 5 to 85 years old. We have three major findings: 1) The inverted U-shaped trajectory is the predominant pattern; 2) Cognitive control-related brain regions exhibit heterogeneous lifespan trajectories: the frontoparietal control network follows inverted U-shaped trajectories, peaking between 24 and 40 years, while the dorsal attention network demonstrates no clear trajectories; 3) Both the youth and the elderly show weaker brain activities and greater left laterality than young to middle-aged adults. These results reveal the lifespan trajectories of cognitive control, highlighting heterogeneous fluctuations in brain networks with age.

Investigating acoustic startle habituation and prepulse inhibition with silent functional MRI and electromyography in young, healthy adults.

Startle habituation and prepulse inhibition (PPI) are distinct measures of different sensory information processes, yet both result in the attenuation of the startle reflex. Identifying startle habituation and PPI neural mechanisms in humans has mostly evolved from acoustic-focused rodent models. Human functional magnetic resonance imaging (fMRI) studies have used tactile startle paradigms to avoid the confounding effects of gradient-related acoustic noise on auditory paradigms and blood-oxygen-level-dependent (BOLD) measures. This study aimed to examine the neurofunctional basis of acoustic startle habituation and PPI in humans with silent fMRI. Using silent fMRI and simultaneous electromyography (EMG) to measure startle, the neural correlates of acoustic short-term startle habituation and PPI [stimulus onset asynchronies (SOA) of 60 ms and 120 ms] were investigated in 42 healthy adults (28 females). To derive stronger inferences about brain-behaviour correlations at the group-level, models included EMG-assessed measures of startle habituation (regression slope) or PPI (percentage) as a covariate. A linear temporal modulator was modelled at the individual-level to characterise functional changes in neural activity during startle habituation. Over time, participants showed a decrease in startle response (habituation), accompanied by decreasing thalamic, striatal, insula, and brainstem activity. Startle habituation was associated with the linear temporal modulation of BOLD response amplitude in several regions, with thalamus, insula, and parietal lobe activity decreasing over time, and frontal lobe, dorsal striatum, and posterior cingulate activity increasing over time. The paradigm yielded a small amount of PPI (9-13%). No significant neural activity for PPI was detected. Startle habituation was associated with the thalamus, putamen, insula, and brainstem, and with linear BOLD response modulation in thalamic, striatal, insula, parietal, frontal, and posterior cingulate regions. These findings provide insight into the mediation and functional basis of the acoustic primary startle circuit. Instead, whilst reduced compared to conventional MRI, scanner noise may have disrupted prepulse detection and processing, resulting in low PPI and impacting our ability to map its neural signatures. Our findings encourage optimisation of the MRI environment for acoustic PPI-based investigations in humans. Combining EMG and functional neuroimaging methods shows promise for mapping short-term startle habituation in healthy and clinical populations.

Investigating the association between symptoms and functional activity in brain regions in schizophrenia: A cross-sectional fmri-based neuroimaging study

Schizophrenia is a persistent neurological disorder profoundly affecting cognitive, emotional, and behavioral functions, prominently characterized by delusions, hallucinations, disordered speech, and abnormal motor activity. These symptoms often present diagnostic challenges due to their overlap with other forms of psychosis. Therefore, the implementation of automated diagnostic methodologies is imperative. This research leverages Functional Magnetic Resonance Imaging (fMRI), a neuroimaging modality capable of delineating functional activations across diverse brain regions. Furthermore, the utilization of evolving machine learning techniques for fMRI data analysis has significantly progressive. Here, our study stands as a novel attempt, focusing on the comprehensive assessment of both classical and atypical symptoms of schizophrenia. We aim to uncover associated changes in brain functional activity. Our study encompasses two distinct fMRI datasets (1.5T and 3T), each comprising 34 schizophrenia patients for the 1.5T dataset and 25 schizophrenia patients for the 3T dataset, along with an equal number of healthy controls. Machine learning algorithms are applied to assess data subsets, enabling an in-depth evaluation of the current functional condition concerning symptom impact. The identified voxels contribute to determining the brain regions most influenced by each symptom, as quantified by symptom intensity. This rigorous approach has yielded various new findings while maintaining an impressive classification accuracy rate of 97 %. By elucidating variations in activation patterns across multiple brain regions in individuals with schizophrenia, this study contributes to the understanding of functional brain changes associated with the disorder. The insights gained may inform differential clinical interventions and provide a means of assessing symptom severity accurately, offering new avenues for the management of schizophrenia.

A - 59 MEG Power Changes in Non-concussed High School Football Players: Implications of Cumulative Head Impact Risk

Abstract Purpose The purpose of this study was to determine how cumulative repetitive head impacts (RHI) over a single season affects functional brain activity in high school football players that are clinically asymptomatic for concussion. Method Pre-season and post-season magnetoencephalography (275 channel CTF MEG) and MRI were acquired for 88 football participant seasons (mean age = 16.09 yrs, mean BMI = 26.32). Helmet-based accelerometer data was collected for each practice and game. Cumulative risk-weighted exposure from linear acceleration (RWELinear) was calculated for each subject. Standard processing and source localization of 8-minutes eyes-open-resting state MEG data was performed using Brainstorm2. Voxel-wise relative power spectral density (PSD) was calculated for the theta frequency band (5-7 Hz). After transformation to MNI space2, pre-season to post-season percent change in PSD (%theta) was calculated and spatial clusters significantly correlated with RWELinear were identified using SPM8 (a = 0.05 and false discovery correction to account for multiple corrections). Mean cluster values were extracted, and linear regression analysis performed in R 3.21 with covariates of BMI, age, and time between scans. Results After covariate adjustment, there was a significant positive correlation between RWELinear and %Δtheta PSD in the right postcentral gyrus and inferior parietal lobe (p = 9.342e-05, adj. R2 = 0.2092), with no other significant associations noted. Conclusions Changes in functional brain activity may be associated with RHI specifically in the right postcentral gyrus and inferior parietal lobe over a typical football season. Future research will include examining how these affected areas are associated with cognitive performance.

The Effects of Osteopathic Manipulative Treatment on Brain Activity: A Scoping Review of MRI and EEG Studies.

Osteopathic manipulative treatment (OMT) is a hands-on therapy aiming to achieve the global homeostasis of the patient. OMT focuses on treating the somatic dysfunctions characterized by tissue modifications, body asymmetry, and range-of-motion restrictions. The benefits related to OMT are thought to be associated with the interconnectedness of the body's systems and the inherent capacity for self-healing. However, whether OMT can influence brain activity, and, consequently, neurophysiological responses is an open research question. Our research investigates the literature to identify the effects of OMT on brain activity. The main purpose of the research question is: can OMT influence brain activity and consequently neurophysiological responses? A scoping review was conducted, searching the following databases: PubMed, Google Scholar, and OSTEOMED.DR (Osteopathic Medical Digital Repository), Scopus, Web of Science (WoS), and Science Direct. The initial search returned 114 articles, and after removing duplicates, 69 were considered eligible to be included in the final sample. In the end, eight studies (six randomized controlled trials, one pilot study, and one cross-over study) were finally included and analyzed in this review. In conclusion, OMT seems to have a role in influencing functional changes in brain activity in healthy individuals and even more in patients with chronic musculoskeletal pain. However, further RCT studies are needed to confirm these findings. Registration protocol: CRD42024525390.

Aberrant Intra- and Inter-Network Connectivity in Idiopathic Sudden Sensorineural Hearing Loss with Tinnitus.

Idiopathic Sudden Sensorineural Hearing Loss (ISSNHL) is related to alterations in brain cortical and subcortical structures, and changes in brain functional activities involving multiple networks, which is often accompanied by tinnitus. There have been many in-depth research studies conducted concerning ISSNHL. Despite this, the neurophysiological mechanisms of ISSNHL with tinnitus are still under exploration. The study aimed to investigate the neural mechanism in ISSNHL patients with tinnitus based on the alterations in intra- and inter-network Functional Connectivity (FC) of multiple networks. Thirty ISSNHL subjects and 37 healthy subjects underwent resting-state functional Magnetic Resonance Imaging (rs-fMRI). Independent Component Analysis (ICA) was used to identify 8 Resting-state Networks (RSNs). Furthermore, the study used a two-sample t-test to calculate the intra-network FC differences, while calculating Functional Network Connectivity (FNC) to detect the inter-network FC differences. By using the ICA approach, tinnitus patients with ISSNHL were found to have FC changes in the following RSNs: CN, VN, DMN, ECN, SMN, and AUN. In addition, the interconnections of VN-SMN, VN-ECN, and ECN-DAN were weakened. The present study has demonstrated changes in FC within and between networks in ISSNHL with tinnitus, providing ideas for further study on the neuropathological mechanism of the disease.

Engaging Mood Brain Circuits with Psilocybin (EMBRACE): a study protocol for a randomized, placebo-controlled and delayed-start, neuroimaging trial in depression

BackgroundMajor depressive disorder (MDD) is a leading cause of disability worldwide across domains of health and cognition, affecting overall quality of life. Approximately one third of individuals with depression do not fully respond to treatments (e.g., conventional antidepressants, psychotherapy) and alternative strategies are needed. Recent early phase trials suggest psilocybin may be a safe and efficacious intervention with rapid-acting antidepressant properties. Psilocybin is thought to exert therapeutic benefits by altering brain network connectivity and inducing neuroplastic changes that endure for weeks post-treatment. Although early clinical results are encouraging, psilocybin’s acute neurobiological effects on neuroplasticity have not been fully investigated. We aim to examine for the first time how psilocybin acutely (intraday) and subacutely (weeks) alters functional brain networks implicated in depression.MethodsFifty participants diagnosed with MDD or persistent depressive disorder (PDD) will be recruited from a tertiary mood disorders clinic and undergo 1:1 randomization into either an experimental or control arm. Participants will be given either 25 mg psilocybin or 25 mg microcrystalline cellulose (MCC) placebo for the first treatment. Three weeks later, those in the control arm will transition to receiving 25 mg psilocybin. We will investigate whether treatments are associated with changes in arterial spin labelling and blood oxygenation level-dependent contrast neuroimaging assessments at acute and subacute timepoints. Primary outcomes include testing whether psilocybin demonstrates acute changes in (1) cerebral blood flow and (2) functional brain activity in networks associated with mood regulation and depression when compared to placebo, along with changes in MADRS score over time compared to placebo. Secondary outcomes include changes across complementary clinical psychiatric, cognitive, and functional scales from baseline to final follow-up. Serum peripheral neurotrophic and inflammatory biomarkers will be collected at baseline and follow-up to examine relationships with clinical response, and neuroimaging measures.DiscussionThis study will investigate the acute and additive subacute neuroplastic effects of psilocybin on brain networks affected by depression using advanced serial neuroimaging methods. Results will improve our understanding of psilocybin’s antidepressant mechanisms versus placebo response and whether biological measures of brain function can provide early predictors of treatment response.Trial registrationClinicalTrials.gov Identifier: NCT06072898. Registered on 6 October 2023.

Transcranial Magnetic Stimulation–Induced Plasticity Improving Cognitive Control in Obsessive-Compulsive Disorder, Part I: Clinical and Neuroimaging Outcomes From a Randomized Trial

BackgroundRepetitive transcranial magnetic stimulation (rTMS) is an emerging treatment for obsessive-compulsive disorder (OCD). The neurobiological mechanisms of rTMS in OCD have been incompletely characterized. We compared clinical outcomes and changes in task-based brain activation following 3 different rTMS protocols, all combined with exposure and response prevention. MethodsIn this 3-arm proof-of-concept randomized trial, 61 treatment-refractory adult patients with OCD received 16 sessions of rTMS immediately before exposure and response prevention over 8 weeks, with task-based functional magnetic resonance imaging scans and clinical assessments before and after treatment. Patients received high-frequency rTMS to the left dorsolateral prefrontal cortex (n = 19 [13 women/6 men]), high-frequency rTMS to the left pre-supplementary motor area (preSMA) (n = 23 [13 women/10 men]), or control rTMS to the vertex (n = 19 [13 women/6 men]). Changes in task-based functional magnetic resonance imaging activation before/after treatment were compared using both a Bayesian region of interest and a general linear model whole-brain approach. ResultsMean OCD symptom severity decreased significantly in all treatment groups (Δ = −10.836, p < .001, 95% CI −12.504 to −9.168), with no differences between groups. Response rate in the entire sample was 57.4%. The dorsolateral prefrontal cortex rTMS group showed decreased planning-related activation after treatment that was associated with greater symptom improvement. No group-level activation changes were observed for the preSMA and vertex rTMS groups. Participants in the preSMA group with greater symptom improvement showed decreased error-related activation, and symptom improvement in the vertex group was associated with increased inhibition-related activation. ConclusionsrTMS to preSMA and dorsolateral prefrontal cortex combined with exposure and response prevention led to activation decreases in targeted task networks in individuals showing greater symptom improvement, although we observed no differences in symptom reduction between groups.

Spontaneous brain activity in patients with central retinal artery occlusion: a resting-state functional MRI study using machine learning.

Central retinal artery occlusion (CRAO) is a serious eye condition that poses a risk to vision, resulting from the blockage of the central retinal artery. Because of the anatomical connection between the ocular artery, which derives from the internal carotid artery, and the anterior middle cerebral artery, hemodynamic alterations and sudden vision loss associated with CRAO may impact brain functionality. This study aimed to examine alterations in spontaneous neural activity among patients with CRAO by resting-state functional MRI. In addition, we selected the amplitude of low-frequency fluctuation (ALFF) and fractional amplitude of low-frequency fluctuation (fALFF) values as classification features for distinguishing CRAO from healthy controls (HCs) using a support vector machine classifier. A total of 18 patients diagnosed with CRAO and 18 HCs participated in the study. Resting-state brain function images and structural images were acquired from both groups. Aberrant changes in spontaneous brain functional activity among CRAO patients were investigated utilizing ALFF and fALFF analysis methods. Group differences in ALFF/fALFF values were assessed through a two-sample t-test. Subsequently, a machine learning classifier was developed to evaluate the clinical diagnostic potential of ALFF and fALFF values. In comparison to HCs, individuals with CRAO exhibited significantly higher ALFF values in the left cerebellum_6, vermis_7, left superior frontal gyrus, and left inferior frontal gyrus, triangular part. Conversely, the CRAO group displayed notably lower ALFF values in the left precuneus and left median cingulum gyri. Furthermore, higher fALFF values were observed in the left inferior frontal gyrus, triangular part, whereas lower fALFF values were noted in the right cerebellum_Crus2, left precuneus, right angular gyrus, left angular gyrus, right supramarginal gyrus, right superior parietal gyrus, and left precuneus. Utilizing the ALFF/fALFF values, the receiver operating characteristic curves (area under the curve) yielded 0.99 and 0.94 through machine learning analysis techniques. CRAO patients exhibit atypical neural activity in the brain, characterized by ALFF and fALFF values predominantly localized in the frontal, parietal, and cerebellar regions, which are closely linked to visual cognition and motor control impairments. Furthermore, ALFF and fALFF could serve as potential neuroimaging markers beyond the orbit among CRAO.

Longitudinal Changes in Functional Neural Activation and Sensitization During Face Processing in Fragile X Syndrome

BackgroundFragile X syndrome (FXS) is a genetic condition associated with increased risk for social anxiety and avoidance. Using functional near-infrared spectroscopy (fNIRS), we previously demonstrated aberrant neural activity responding to faces in young girls with FXS cross-sectionally. Here, we tested the hypothesis that abnormalities in neural activation and sensitization would increase with age in 65 girls with FXS (ages 6–16 years) relative to an age-matched control group of 52 girls who had comparable cognitive function and clinical symptoms. MethodsfNIRS data were collected at 2 time points (mean [SD] = 2.8 [0.6] years apart) during a face processing task. Linear mixed-effect models examined longitudinal neural profiles in girls with FXS and control participants. Correlational analysis was performed to examine associations between neural sensitization (increasing neural response to repeated stimuli) and clinical ratings. ResultsIn the FXS group, 24 participants had 1 fNIRS scan, and 32 had 2 scans. In the control group, 28 participants had 1 fNIRS scan, and 22 had 2 scans. Brain activations in the superior frontal gyrus were higher in girls with FXS than control participants at both time points. Neural sensitization also increased in girls with FXS at a higher rate than control participants in the superior frontal gyrus when responding to upright faces. For the FXS group, sensitization in the superior frontal gyrus positively correlated with longitudinal increases in anxiety and social avoidance scores. ConclusionsGirls with FXS show increasingly abnormal neural activation and sensitization responding to faces over time. Aberrant neural sensitization in girls with FXS is associated with longitudinal changes in anxiety and social skills.

Ecological and comparative analysis of the influence of the weather factor under the combined effect of heliomagnetic storms (HMS) on the vegetative balance of boys of different ages

Despite the extensive scientific data available on the impact of meteorological and heliogeophysical factors on the health and physiological parameters of the organism, the ecological role and biological nature of the mechanisms of their interaction remain unclear. The need to choose an integrated approach to the study of the Space–Earth–Human system is obvious and justified because it is based on the idea of using modern technologies and channels for obtaining and disseminating information about the impact of space weather, variability of the atmosphere, electromagnetic and gravitational fields, anthropogenic pollution and other environmental parameters that requires effective and rapid solution. It has been established that the body’s response to various stressful influences is largely determined by the ratio of the tone of the sympathetic and parasympathetic divisions of the autonomic nervous system. It is the autonomic nervous system (ANS) and, above all, its sympathetic division that plays a special role in the formation of adaptive reactions of the body, the development of meteorological reactions, i.e. the autonomic nervous system is the primary site of meteorological influences that cause shifts in its balance. Determination of vegetative status and direction of vegetative activity in boys’ organism was carried out by means of functional and vegetative diagnostics by V. Makats’ method. We examined 151 boys, including 49 boys aged 7–11 years and 102 — aged 12–15 years, FVD was carried out in the morning at 10.00–11.00. Since the state of the autonomic nervous system is decisive in the development of meteotropic reactions, the data of the study of vegetative tone in sunny and cloudy weather under the combined influence of heliomagnetic storms (HMS) were analysed, favourable and unfavourable weather conditions for the body were determined and the state of adaptive health of the examined children was determined. It was found that under the influence of heliometeorological factors on the organism of practically healthy young boys, agerelated peculiarities of meteorological variability are observed. The most sensitive to changes in weather and climatic conditions under the combined influence of HMS was the group of primary school age boys (PSA) aged 7–11 years, who showed maximum deviations in the activity of functional systems from the age norm, and the least sensitive was the group of boys aged 12–15 years. When analysing the influence of changes in weather conditions on the body of boys by the vegetative coefficient (kV), it was found that at the norm of kAv 0.95–1.05, it increased maximally when exposed to sunny weather and amounted to 1.12 in the revealed state of vegetative balance. In a healthy organism, changes in physiological processes and functional activity of systems under the influence of such a factor as changes in boys’ PSA, which indicates a pronounced sympathicotonia, and in boys’ ASA 0.93, respectively, which indicates a slight parasympathicotonia. The effects of cloudy weather on the body in both groups, even with the combined effect of HMB, are easily compensated for, and a special role in this belongs to the autonomic nervous system, whose activity ensures an adequate response of the body to the effects of environmental factors. Knowledge about meteosensitivity and meteorological reactions is necessary for the development of both preventive and therapeutic measures aimed at increasing nonspecific resistance and adaptation mechanisms of the body, normalising the function of organs and systems as a basis for normal reactions to adverse environmental changes. Environmental factors, including meteorological factors, are directly related to human life and health. Each of the meteorological elements has its own biological significance. This raises the question of the impact of solar activity, weather, atmospheric conditions, and, above all, anthropogenic pollution and other environmental parameters on human health, which naturally requires a quantitative approach to risk assessment and the development of necessary management decisions.

Responsiveness and construct validity of two outcome measures of bilateral upper limb function in patients with chronic stroke

BackgroundStroke is a leading cause of long-term disability among stroke survivors. Despite the availability of numerous stroke rehabilitative therapies, such as mirror therapy, bilateral arm training, and robot-assisted therapy, the recovery of motor function after stroke remains incomplete. Bilateral arm function is a key component in stroke patients to perform activities of daily living and to reflect their functional autonomy.ObjectiveThis clinimetric study investigated and compared the construct validity and responsiveness of 2 bimanual activity outcome measures, the Chedoke Arm and Hand Activity Inventory (CAHAI) and the ABILHAND Questionnaire, in individuals receiving stroke rehabilitation.MethodsThe present study is a secondary analysis following the framework of the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN). Individuals with chronic stroke (N = 113) were recruited from outpatient rehabilitation settings. Participants received 18 to 20 sessions of robot-assisted therapy, mirror therapy, combined therapy, or conventional rehabilitation for 4 to 6 weeks. The CAHAI, ABILHAND Questionnaire, and a comparison instrument, the Motor Activity Log (MAL), were administered twice at a 4- to 6-week interval to all participants. ABILHAND scores, in logits, were converted from raw ordinal scores into a linear measure.ResultsThere was medium to large correlation of the CAHAI and the MAL (ρ = 0.60–0.62, p &amp;lt; 0.01) as well as the ABILHAND Questionnaire and the MAL (ρ = 0.44–0.51, p &amp;lt; 0.01). Change scores from the initial measurement to the post-intervention measurement demonstrated small to medium correlation of the CAHAI and the MAL (ρ = 0.27–0.31, p &amp;lt; 0.01) and medium to large correlation of the ABILHAND Questionnaire and the MAL (ρ = 0.37–0.41, p &amp;lt; 0.01). Overall, 7 of 8 hypotheses were supported. The hypothesis testing regarding the construct validity and responsiveness of the CAHAI and ABILHAND Questionnaire was confirmed.ConclusionThe CAHAI and ABILHAND Questionnaire are both responsive and suitable to detect changes in bilateral arm functional daily activities in individuals with chronic stroke. Patient-reported outcome measures are recommended to use along with therapist-rated outcome measures for upper limb capacity evaluation in stroke rehabilitation. Further study with a prospective study design to capture specific clinical features of participants and the use of body-worn sensors, such as the arm accelerometer, is suggested.

Dose-dependent LSD effects on cortical/thalamic and cerebellar activity: brain oxygen level-dependent fMRI study in awake rats.

Lysergic acid diethylamide is a hallucinogen with complex neurobiological and behavioural effects. This is the first study to use MRI to follow functional changes in brain activity in response to different doses of lysergic acid diethylamide in fully awake, drug-naive rats. We hypothesized that lysergic acid diethylamide would show a dose-dependent increase in activity in the prefrontal cortex and thalamus while decreasing hippocampal activity. Female and male rats were given intraperitoneal injections of vehicle or lysergic acid diethylamide in doses of 10 or 100 µg/kg while fully awake during the imaging session. Changes in blood oxygen level-dependent signal were recorded over a 30-min window. Approximately 45-min post-injection data for resting-state functional connectivity were collected. All data were registered to rat 3D MRI atlas with 173 brain regions providing site-specific increases and decreases in global brain activity and changes in functional connectivity. Treatment with lysergic acid diethylamide resulted in a significant dose-dependent increase in negative blood oxygen level-dependent signal. The areas most affected were the primary olfactory system, prefrontal cortex, thalamus and hippocampus. This was observed in both the number of voxels affected in these brains regions and the changes in blood oxygen level-dependent signal over time. However, there was a significant increase in functional connectivity between the thalamus and somatosensory cortex and the cerebellar nuclei and the surrounding brainstem areas. Contrary to our hypothesis, there was an acute dose-dependent increase in negative blood oxygen level-dependent signal that can be interpreted as a decrease in brain activity, a finding that agrees with much of the behavioural data from preclinical studies. The enhanced connectivity between thalamus and sensorimotor cortices is consistent with the human literature looking at lysergic acid diethylamide treatments in healthy human volunteers. The unexpected finding that lysergic acid diethylamide enhances connectivity to the cerebellar nuclei raises an interesting question concerning the role of this brain region in the psychotomimetic effects of hallucinogens.

The phase coherence of the neurovascular unit is reduced in Huntington’s disease

Abstract Huntington’s disease is a neurodegenerative disorder in which neuronal death leads to chorea and cognitive decline. Individuals with ≥40 cytosine–adenine–guanine repeats on the interesting transcript 15 gene develop Huntington’s disease due to a mutated huntingtin protein. While the associated structural and molecular changes are well characterized, the alterations in neurovascular function that lead to the symptoms are not yet fully understood. Recently, the neurovascular unit has gained attention as a key player in neurodegenerative diseases. The mutant huntingtin protein is known to be present in the major parts of the neurovascular unit in individuals with Huntington’s disease. However, a non-invasive assessment of neurovascular unit function in Huntington’s disease has not yet been performed. Here, we investigate neurovascular interactions in presymptomatic (N = 13) and symptomatic (N = 15) Huntington’s disease participants compared to healthy controls (N = 36). To assess the dynamics of oxygen transport to the brain, functional near-infrared spectroscopy, ECG and respiration effort were recorded. Simultaneously, neuronal activity was assessed using EEG. The resultant time series were analysed using methods for discerning time-resolved multiscale dynamics, such as wavelet transform power and wavelet phase coherence. Neurovascular phase coherence in the interval around 0.1 Hz is significantly reduced in both Huntington’s disease groups. The presymptomatic Huntington’s disease group has a lower power of oxygenation oscillations compared to controls. The spatial coherence of the oxygenation oscillations is lower in the symptomatic Huntington’s disease group compared to the controls. The EEG phase coherence, especially in the α band, is reduced in both Huntington’s disease groups and, to a significantly greater extent, in the symptomatic group. Our results show a reduced efficiency of the neurovascular unit in Huntington’s disease both in the presymptomatic and symptomatic stages of the disease. The vasculature is already significantly impaired in the presymptomatic stage of the disease, resulting in reduced cerebral blood flow control. The results indicate vascular remodelling, which is most likely a compensatory mechanism. In contrast, the declines in α and γ coherence indicate a gradual deterioration of neuronal activity. The results raise the question of whether functional changes in the vasculature precede the functional changes in neuronal activity, which requires further investigation. The observation of altered dynamics paves the way for a simple method to monitor the progression of Huntington’s disease non-invasively and evaluate the efficacy of treatments.

Resting-state functional connectivity of amygdala subregions predicts treatment outcome for cognitive behavioral therapy in obsessive-compulsive disorder at a 4-month follow-up

BackgroundCognitive behavioral therapy (CBT) is considered as the first-line treatment for obsessive-compulsive disorder (OCD). However, the underlying neural mechanisms through which CBT exerts its effects in OCD remain unclear. This study aims to investigate whether the improvement of clinical symptoms in OCD patients after CBT treatment is associated with changes in resting-state functional connectivity (FC) of the amygdala subregion, and whether these changes can be served as potential predictors of four-months treatment efficacy. MethodsWe collected resting-state functional magnetic resonance imaging (rs-fMRI) data from 57 OCD patients and 50 healthy subjects at baseline. In the patient group, rs-fMRI was also obtained after completion of an 8-week CBT treatment and 4 months post-treatment. A whole-brain rsFC analysis was conducted using the amygdala subregion as the seed point. We analyzed the FC patterns in relation to 4 months clinical outcomes to elucidate the long-term efficacy of CBT in OCD patients. ResultsTreatment responseat at pre-treatment was found to be associated with reduced rsFC between the left basolateral amygdala(BLA)and left superior temporal gyrus(STG) at baseline. Lower pre-treatment FC were negatively correlated with the severity of OCD symptoms as measured by the Yale-Brown Obsessive Compulsive Severity Scale (Y-BOCS). Moreover, the area under the receiver operating characteristic (ROC) curve for the FC between the left BLA and STG at the end of treatment was 73.0% and 70.4% for the effective-ineffective and remitted or unremitted groups, respectively. At the 4-month follow-up, the area under the ROC curve for the effective-ineffective and remitted or unremitted groups was 83.9% and 76.5%, respectively. ConclusionThese findings suggest that brain functional activity in patients with OCD can predict treatment response to CBT, and longitudinal changes in relevant brain functional activity following CBT treatment are associated with treatment response in OCD.

Reproductive capacity of male bank voles (Myodes glareolus Schreber, 1780) – age-dependent changes in functional activity of epididymal sperm

The influence of age on male bank voles’ reproductive tract development, epididymal sperm quantity and functional activity was investigated. Experiments were carried out on male bank voles aged 1.5 to 15 months (n=10 each in 8 age groups). The developmental stage of the reproductive tract was assessed by the weight of testes, seminal vesicles and coagulation glands. In each age group the number of epididymal sperm and their functional activity were examined. Epididymal sperm functional activity was assessed by motility, viability, maturity, head morphology and integrity of the sperm tail membrane. Ageing males were heavier than pre-pubertal and mature ones. Male age also affected the testes, seminal vesicles and coagulation gland development. The heaviest accessory sex glands were noted in 3-month-old males and the lightest in pre-pubertal (1.5-month-old) and older (12- and 15-month-old) males. Sperm counts were significantly higher in 3-, 4- and 5-month-old males than in pre-pubertal and old males. Generally, adult males aged 3- and 4- months, produced sperm of better functional activity. In conclusion, the best male reproductive capacity is found in bank voles of 3 to 4 months of age.