Journal of integrative neuroscience最新文献

Background: In this study, we explored the interplay between exogenous orienting attention and emotional audiovisual integration (AVI) via electroencephalography (EEG).

Methods: We designed a 2 (cue validity: valid, invalid) × 3 (emotion types: happiness, neutral and sadness) × 3 (modality: visual, auditory, audiovisual) discrimination task on the basis of the cue-target paradigm. Twenty-two participants (average age: 21.71 ± 1.84 years; 13 females, 9 males) were enrolled in this experiment. Participants were asked to respond to three emotional stimuli presented in different modalities by pressing a corresponding key.

Results: The results indicated faster responses to multisensory stimuli than to unisensory stimuli and to the valid cue condition than to the invalid cue condition, which indicated multisensory advantage and cueing effect occurred. In addition, happiness stimuli induced the fastest response compared with neutral and sadness emotion stimuli. EEG findings indicated a reduction in audiovisual integration induced by valid exogenous orienting in the frontal, central and parietal lobe regions. Moreover, neutral emotional stimuli elicited greater audiovisual integration than stimuli expressing happiness and sadness did.

Conclusions: Overall, valid exogenous cues and emotional processing decreased audiovisual integration. The present study sheds light on how exogenous attention modulates emotional audiovisual integration and highlights the complex interactions among attention, sensory processing, and the emotional context in multisensory perception.

Epilepsy, a chronic neurological disorder characterized by recurrent seizures, affects a significant portion of the global population, with drug-resistant epilepsy (DRE) presenting a major treatment challenge. Insular epilepsy, originating from this complex region, exhibits a broad range of symptoms, making diagnosis particularly difficult. Advanced imaging techniques and invasive procedures like stereoelectroencephalography (SEEG) are often crucial for accurately localizing the epileptogenic zone. Surgical resection remains the primary treatment for DRE, with recent advancements in microsurgical techniques and neuroimaging improving outcomes. Additionally, minimally invasive approaches like laser interstitial thermal therapy (LITT) and radiofrequency thermocoagulation (RFTC) offer promising alternatives.

Background: Precise localization of intracerebral implants in rodent brains is required for physiological and behavioral studies, particularly if targeting deep brain nuclei. Traditional histological methods, based on manual estimation through sectioning can introduce errors and complicate data interpretation.

Methods: Here, we introduce an alternative method based on recent advances in tissue-clearing techniques and light-sheet fluorescence microscopy. This method uses a simplified recipe of the Clear, Unobstructed Brain/Body Imaging Cocktails and Computational Analysis (CUBIC) method, which is a rapid clearing procedure using an aqueous-based solution compatible with fluorescence and fluorescence markers. We demonstrate the utility of this approach in anesthetized transgenic mice expressing channelrhodopsin-2 (ChR2) and enhanced yellow fluorescent fusion (EYFP) protein under the choline acetyltransferase (ChAT) promoter/enhancer regions (ChAT-ChR2-EYFP mice) with implanted linear silicon optrode probes into the midbrain interpeduncular nucleus (IPN).

Results: By applying the red fluorescent DiD' dye (DiIC₁₈(5) solid (1,1'-Dioctadecyl-3,3,3',3'-Tetramethylindodicarbocyanine, 4-Chlorobenzenesulfonate Salt) to the electrode surface, we precisely visualize the electrode localization in the IPN of ChAT-ChR2-EYFP mice. Three-dimensional brain videos from different orientations highlight the potential of this method. Optogenetic responses recorded from electrodes placed in the IPN validate these findings.

Conclusions: This method allows for precise localization of brain implantation sites in transgenic mice expressing cell-specific fluorescence markers. It enables virtual brain slicing in any orientation, making it a useful tool for functional studies in mice.

Background: This research aimed to delve into the cortical morphological transformations in patients with magnetic resonance imaging (MRI)-negative temporal lobe epilepsy (TLE-N), seeking to uncover the neuroimaging mechanisms behind these changes.

Methods: A total of 29 individuals diagnosed with TLE-N and 30 healthy control participants matched by age and sex were selected for the study. Using the surface-based morphometry (SBM) technique, the study analyzed the three-dimensional-T1-weighted MRI scans of the participants' brains. Various cortical structure characteristics, such as thickness, surface area, volume, curvature, and sulcal depth, among other parameters, were measured.

Results: When compared with the healthy control group, the TLE-N patients exhibited increased insular cortex thickness in both brain hemispheres. Additionally, there was a notable reduction in the curvature of the piriform cortex (PC) and the insular granular complex within the right hemisphere. In the left hemisphere, the volume of the secondary sensory cortex (OP1/SII) and the third visual area was significantly reduced in the TLE-N group. However, no significant differences were found between the groups regarding cortical surface area and sulcal depth (p < 0.025 for all, corrected by threshold-free cluster enhancement).

Conclusions: The study's initial findings suggest subtle morphological changes in the cerebral cortex of TLE-N patients. The SBM technique proved effective in identifying brain regions impacted by epileptic activity. Understanding the microstructural morphology of the cerebral cortex offers insights into the pathophysiological mechanisms underlying TLE.

Background: The insulin-like growth factor (IGF) system plays a vital role in regulating gonadotropin-releasing hormone (GnRH), whether the IGF2 can act on the GnRH neurons during the pubertal period is unclear.

Methods: Central precocious puberty (CPP) rats were induced by danazol, and when the rats met the first diestrus, they were euthanized and tissues were collected. GT1-7 cells were cultured and treated with 0, 1, 10 ng/mL IGF2 for 4 hours and the changes in GnRH were measured. Mice were injected intracerebroventricularly with IGF2 (15 ng/g, 5 μL) or with the same dose of phosphate buffered saline (PBS), after eight hours, they were euthanized and tissues collected.

Results: CPP rats had increased expression of IGF2 and GnRH mRNA and their respective proteins in the preoptic area (POA) of the hypothalamus. Treatment of GT1-7 cells with 10 ng/mL of IGF2 increased GnRH mRNA and protein expression, and GnRH concentration in the culture medium. Injection of IGF2 protein into the lateral ventricle of mice increased the expression of GnRH mRNA and protein in the POA.

Conclusions: IGF2 may upregulate the synthesis of GnRH during the pubertal period, and may also take part in the pathology of CPP.

Background: The goal of these experiments was to determine which learning and memory system(s) were necessary for the retention of visual discriminations and subsequent acquisition of a second problem. The dorsal striatum should be involved in the acquisition and expression of this task based on previous work implicating this region in instrumental learning and memory processes. The perirhinal cortex has been implicated in learning and memory processes associated with visual information like objects, and pictures and may also play a role in the acquisition and/or retention of visual discriminations. As there is no clear spatial/relational component to the task, the hippocampus should not be involved.

Methods: Rats were trained on a two-choice visual discrimination task to criterion performance after which they received lesions to portions of the dorsal striatum (dorso-medial or dorso-lateral striatum) and medial temporal lobe (perirhinal cortex or hippocampus). After surgical recovery, the rats were tested for retention of the original discrimination, followed by training on a second problem on the same task.

Results: The results showed that dorsal medial striatal lesions produced a retrograde deficit on picture discrimination, but dorsal lateral striatum lesions did not. Neither dorsal striatal lesion produced a deficit on acquisition of a second problem. Perirhinal cortex did not seem to make an essential contribution to the retention of the original discrimination or acquisition of the second problem. Surprisingly, subjects with hippocampal damage were severely impaired but eventually re-learned the discrimination. Damage to the hippocampus had no impact on acquisition of a second problem.

Conclusions: Taken together, the results of the present experiments show that the dorsomedial striatum and the hippocampus may support performance on this instrumental task if intact during acquisition but is not required for acquisition of a new problem. The implications of this pattern of results for our understanding of the organization of learning and memory in mammals is discussed.

Background: Parkinson's disease (PD) is currently the second most common degenerative neurological disorder globally, with aspiration pneumonia caused by difficulty swallowing being the deadliest complication. The patient's subjective experience and the safety of swallowing have been the main focus of previous evaluations and treatment plans. The effectiveness of treatment may be attributed to the brain's ability to adapt and compensate. However, there is a need for more accurate assessment methods for dysphagia and further research on how treatment protocols work.

Objective: This systematic review was designed to assess the effectiveness and long-term impact of published treatment options for swallowing disorders in patients with PD.

Methods: In adherence to the Preferred Reporting Items for Reviews and Meta-analysis (PRISMA) guidelines, we conducted a systematic review where we thoroughly searched multiple databases (PubMed, Web of Science, Elsevier, and Wiley) for clinical studies published in various languages until December, 2023. Two reviewers evaluated the studies against strict inclusion/exclusion criteria.

Results: This systematic review included a total of 15 studies, including 523 participants, involving six treatment approaches, including breath training, deep brain stimulation, reduction of upper esophageal sphincter (UES) pressure, transcranial magnetic stimulation, postural compensation, and video-assisted swallowing therapy. Primary outcomes included video fluoroscopic swallowing study (VFSS), fiberoptic endoscopic evaluation of swallowing (FEES), high-resolution pharyngeal impedance manometry (HPRIM), and functional magnetic resonance imaging (fMRI).

Conclusion: Treatments that reduce UES resistance may be an effective way to treat dysphagia in PD patients. HRPIM can quantify pressure changes during the pharyngeal period to identify patients with reduced swallowing function earlier. However, due to the limited number of randomized controlled trials (RCTs) included and the high risk of bias in some studies, large-scale RCTs are needed in the future, and objective indicators such as HRPIM should be used to determine the effectiveness and long-term impact of different therapies on dysphagia in PD patients.

Glial cells, including astrocytes and microglia, are pivotal in maintaining central nervous system (CNS) homeostasis and responding to pathological insults. This review elucidates the complex immunomodulatory functions of glial cells, with a particular focus on their involvement in inflammation cascades initiated by the accumulation of alpha-synuclein (α-syn), a hallmark of Parkinson's disease (PD). Deriving insights from studies on both sporadic and familial forms of PD, as well as animal models of PD, we explore how glial cells contribute to the progression of inflammation triggered by α-syn aggregation. Additionally, we analyze the interplay between glial cells and the blood-brain barrier (BBB), highlighting the role of these cells in maintaining BBB integrity and permeability in the context of PD pathology. Furthermore, we delve into the potential activation of repair and neuroprotective mechanisms mediated by glial cells amidst α-syn-induced neuroinflammation. By integrating information on sporadic and familial PD, as well as BBB dynamics, this review aims to deepen our understanding of the multifaceted interactions between glial cells, α-syn pathology, and CNS inflammation, thereby offering valuable insights into therapeutic strategies for PD and related neurodegenerative disorders.

Introduction: This research aimed to investigate the pathophysiological mechanism of how drug-induced parkinsonism (DIP) affects the integrity of the white matter (WM) fiber microstructure as measured by magnetic resonance diffusion tensor image (DTI) fractional anisotropy (FA) and mean diffusivity (MD).

Methods: We recruited 17 participants diagnosed with DIP, 20 Parkinson's disease (PD) patients, and 16 normal controls (NCs) with a similar age, gender, and years of education. Subsequently, all participants underwent DTI magnetic resonance imaging scanning. To analyze the data, we utilized the software packages Functional MRI of the Brain Centre (FMRIB) Diffusion Toolbox (FDT), developed by the FMRIB laboratory at Oxford University, and tract-based spatial statistics (TBSS).

Results: The Argentina Hyposmia Rating Scale (AHRS) scores of patients in DIP group were markedly higher than those in PD patients group. Compared with the NC group, the FA values in the genu and body of the corpus callosum (CC), anterior limb of the right internal capsule, bilateral anterior corona radiata, bilateral superior corona radiata, right external capsule, and right superior fronto-occipital fasciculus (could be a part of the anterior internal capsule) were significantly decreased in the DIP group; however, no significant cluster was found in MD.

Conclusions: The present study provides novel insights into the alterations in WM microstructure among DIP patients, suggesting that these methodologies have the potential to aid in the early diagnosis and treatment of DIP.