Ultrasound has emerged as a non-invasive neural modulation technique. Its mechanisms of action in the brain involve mechanical, cavitation, and thermal effects, which modulate neural activity by activating mechanosensitive ion channels, enhancing cell permeability, and improving blood circulation. The ultrasound-piezo-electric systems, based on the coupling between ultrasound and piezoelectric materials, can generate wireless electrical stimulation to promote neural repair, significantly improving therapeutic outcomes for neurodegenerative diseases and showing potential as a replacement for traditional invasive deep brain stimulation techniques. The ultrasound-responsive piezoelectric drug delivery system combines mechano-electrical conversion capability of piezoelectric materials with the non-invasive penetration advantage of ultrasound. This system achieves synergistic therapeutic effects for neurodegenerative diseases through on-demand drug release and wireless electrical stimulation in deep brain regions. It can effectively overcome the blood-brain barrier limitation, enabling precisely targeted drug delivery to specific brain regions. Simultaneously, it generates electrical stimulation in deep brain areas to exert synergistic neuroreparative effects. Together, these capabilities provide a more precise, efficient, and safe solution for treating neurodegenerative diseases. This review summarizes the neural regulatory mechanisms, technical advantages, and research progress of the ultrasound-responsive piezoelectric drug delivery systems for neurodegenerative disease therapy, aiming to offer novel insights for the field.
Humans ; Neurodegenerative Diseases/drug therapy* ; Drug Delivery Systems/methods* ; Blood-Brain Barrier ; Ultrasonic Waves ; Brain ; Ultrasonic Therapy ; Deep Brain Stimulation/methods*

In recent years, cardiovascular disease has become a common disease. With the development of machine learning and big data technologies, the processing ability of electrocardiogram (ECG) signals has been greatly enhanced through new computer technologies, enabling the auxiliary diagnosis technology for cardiovascular disease (CVD) to achieve new improvements. This article discusses the application of machine learning in ECG processing, especially in the auxiliary diagnosis of diseases. Firstly, the conventional signal preprocessing methods are introduced, and then the EEG signal processing methods based on feature extraction and fuzzy classification are explored. Secondly, the application of auxiliary diagnosis in CVD is further summarized. Finally, the advantages and disadvantages of the two methods are analyzed, and based on this, a design of an auxiliary diagnostic system compatible with the two methods is proposed, providing a new perspective for similar applied researches in the future.
Machine Learning ; Cardiovascular Diseases/diagnosis* ; Humans ; Electrocardiography ; Signal Processing, Computer-Assisted ; Diagnosis, Computer-Assisted ; Fuzzy Logic ; Electroencephalography

Brain-computer interface (BCI) technology is an innovative and cutting-edge medical advancement that enables direct interaction between the brain and external devices, facilitating the reconstruction of daily functions for patients or serving as a method for neuro-regulation therapy. Although this technology offers a broad range of clinical applications, there are problems as potential risks, individual variations, and the need for long-term monitoring of its effects during utilization. Consequently, the comprehensive evaluation of its safety and effectiveness poses a considerable challenge for regulatory agencies. This study provides a concise introduction to the development history and various types of BCI technology, followed by a summary of the regulatory situation for different types of BCI medical devices in the United States. Furthermore, the regulatory requirements imposed by the US FDA on this product category are analyzed. Finally, the article concludes by presenting a summary and future perspective on the current development of BCI technology, with the aim of offering beneficial insights and guidance for the regulation of BCI medical devices.
Brain-Computer Interfaces ; United States ; United States Food and Drug Administration ; Humans ; Electroencephalography

In order to improve the effect of transcranial electrical stimulation treatment and realize personalized treatment for patients with varying severity levels, this paper designed an integrated four-channel EEG recording multimodal transcranial electrical stimulation system. This system can conduct real-time monitoring on EEG and related characteristic analysis before stimulation, in stimulation, and after stimulation. This enables physicians and researchers to resolve real-time brain states, evaluate transcranial electrical stimulation effect, and then artificially adjust the stimulation parameters. After relevant testing and verification, the system can select four stimulation modes: TACS, TDCS, TPCS and TRNS, which can output the constant stimulation current of 0.03 mA accuracy in the range of ±2 mA and the stimulation frequency of low frequency of 0~4 kHz (precision of 0.01 Hz) and high frequency 50~100 kHz, which can obtain more accurate EEG signals under stimulation interference, demonstrating a good market application prospect.
Electroencephalography/methods* ; Transcranial Direct Current Stimulation/instrumentation* ; Humans ; Equipment Design

Neural oscillatory changes play a critical role in pain and analgesia research. Previous studies on pain-related neural oscillations have primarily utilized electroencephalogram (EEG) power spectral analysis, revealing a strong correlation between alpha ( α) power and subjective pain perception. However, alpha power may be influenced by the baseline of the power spectrum, making it difficult to accurately capture the true changes in alpha oscillations. This study employed power spectral analysis and further applied a power spectral parameterization method, which decomposed the power spectrum into periodic and aperiodic components, to compare EEG α power in 50 primiparous women who underwent severe pain during the first stage of labor before and after epidural analgesia. The results indicated no significant differences in α power between pre- and post-analgesia conditions. However, following power spectral parameterization, the aperiodic component of the EEG significantly decreased after analgesia, whereas the periodic component of α power showed a significant increase. This study not only validates the effectiveness and validity of the power spectral parameterization method in analgesia research but also uncovers the differential regulatory mechanism by which analgesia modulates the periodic and aperiodic components of α oscillations.
Humans ; Electroencephalography/methods* ; Female ; Adult ; Alpha Rhythm ; Pregnancy ; Young Adult ; Analgesia, Epidural

During long-duration manned space missions, the complex and extreme space environment exerts significant impacts on astronauts' physiological, psychological, and cognitive functions, thereby posing direct risks to mission safety and operational efficiency. As a key bridge between the brain and external devices, brain-computer interface (BCI) technology enables precise acquisition and interpretation of neural signals, offering a novel paradigm for human-machine collaboration in manned spaceflight. Non-invasive BCI technology shows broad application prospects across astronaut selection, mission training, in-orbit task execution, and post-mission rehabilitation. During mission preparation, multimodal signal assessment and neurofeedback training based on BCI can effectively enhance cognitive performance and psychological resilience. During mission execution, BCI can provide real-time monitoring of physiological and psychological states and enable intention-based device control, thereby improving operational efficiency and safety. In the post-mission rehabilitation phase, non-invasive BCI combined with neuromodulation may improve emotional and cognitive functions, support motor and cognitive recovery, and contribute to long-term health management. However, the application of BCI in space still faces challenges, including insufficient signal robustness, limited system adaptability, and suboptimal data processing efficiency. Looking forward, integrating multimodal physiological sensors with deep learning algorithms to achieve accurate monitoring and individualized intervention, and combining BCI with virtual reality and robotics to develop intelligent human-machine collaboration models, will provide more efficient support for space missions.
Brain-Computer Interfaces ; Humans ; Space Flight ; Astronauts/psychology* ; Neurofeedback ; Cognition ; Electroencephalography ; Man-Machine Systems

Abuse of amphetamine-based stimulants is a primary public health concern. Recent studies have underscored a troubling escalation in the inappropriate use of prescription amphetamine-based stimulants. However, the neurophysiological mechanisms underlying the impact of acute methamphetamine exposure (AME) on sleep homeostasis remain to be explored. This study employed non-human primates and electroencephalogram (EEG) sleep staging to evaluate the influence of AME on neural oscillations. The primary focus was on alterations in spindles, delta oscillations, and slow oscillations (SOs) and their interactions as conduits through which AME influences sleep stability. AME predominantly diminishes sleep-spindle waves in the non-rapid eye movement 2 (NREM2) stage, and impacts SOs and delta waves differentially. Furthermore, the competitive relationships between SO/delta waves nesting with sleep spindles were selectively strengthened by methamphetamine. Complexity analysis also revealed that the SO-nested spindles had lost their ability to maintain sleep depth and stability. In summary, this finding could be one of the intrinsic electrophysiological mechanisms by which AME disrupted sleep homeostasis.
Animals ; Methamphetamine ; Electroencephalography ; Male ; Sleep/drug effects* ; Central Nervous System Stimulants ; Delta Rhythm/drug effects* ; Sleep Stages/drug effects*

OBJECTIVES: To explore the relationship between the Observer's Assessment of Alertness/Sedation (OAAS) score and the bispectral index (BIS) during propofol titration for general anesthesia induction and analyze the impact of BIS monitoring delay on anesthetic depth assessment. METHODS: This study was conducted among 90 patients (ASA class I-II) undergoing elective surgery under general anesthesia. For anesthesia induction, the patients received propofol titration at the rate of 0.5 mg·kg^-1·min^-1 till OAAS scores of 4, 3, 2, and 1 were reached. After achieving an OAAS score of 1, remifentanil (2 μg·kg⁻¹) and rocuronium (0.6 mg·kg⁻¹) were administered, and tracheal intubation was performed 2 min later. BIS values, mean arterial pressure (MAP), heart rate (HR), and propofol dosage at each OAAS score were recorded, and the correlation between OAAS scores and BIS values was analyzed. The diagnostic performance of BIS values for determining when the OAAS score reaches 1 was analyzed using ROC curve. RESULTS: All the patients successfully completed tracheal intubation. BIS values of the patients at each of the OAAS scores differed significantly (P<0.01), and the mean BIS value decreased by 4.08, 8.32, 5.43 and 5.24 as the OAAS score decreased from 5 to 4, from 4 to 3, from 3 to 2, and from 2 to 1, respectively. There was a significant correlation between the OAAS score and BIS values (ρ=0.775, P<0.001). The median BIS value for an OAAS score of 1 was 76, at which point 83.33% of the patients had BIS values exceeding 60. ROC curve analysis showed that for determining an OAAS score of 1, BIS value, at the optimal cutoff value of 84, had a sensitivity of 88.9%, a specificity of 73.3%, and an area under the curve of 0.842 (0.803-0.881). CONCLUSIONS OAAS score during induction of general anesthesia is strongly correlated with BIS value and is a highly sensitive and timely indicator to compensate for the delay in BIS monitoring.
Humans ; Propofol/administration & dosage* ; Male ; Female ; Middle Aged ; Anesthesia, General/methods* ; Adult ; Consciousness Monitors ; Aged ; Young Adult ; Monitoring, Intraoperative/methods* ; Electroencephalography

OBJECTIVES: To assess the regulatory effect of cannabidiol (CBD) on circadian rhythm sleep disorders following general anesthesia and explore its potential mechanism in a rat model of propofol-induced rhythm sleep disorder. METHODS: An electrode was embedded in the skull for cortical EEG recording in 24 male SD rats, which were randomized into control, propofol, CBD treatment, and diazepam treatment groups (n=6). Eight days later, a single dose of propofol (10 mg/kg) was injected via the tail vein with anesthesia maintenance for 3 h in the latter 3 groups, and daily treatment with saline, CBD or diazepam was administered via gavage; the control rats received only saline injection. A wireless system was used for collecting EEG, EMG, and body temperature data within 72 h after propofol injection. After data collection, blood samples and hypothalamic tissue samples were collected for determining serum levels of oxidative stress markers and hypothalamic expressions of the key clock proteins. RESULTS: Compared with the control rats, the rats with CBD treatment showed significantly increased sleep time at night (20:00-6:00), especially during the time period of 4:00-6:00 am. Compared with the rats in propofol group, which had prolonged SWS time and increased sleep episodes during 18:00-24:00 and sleep-wake transitions, the CBD-treated rats exhibited a significant reduction of SWS time and fewer SWS-to-active-awake transitions with increased SWS aspects and sleep-wake transitions at night (24:00-08:00). Diazepam treatment produced similar effect to CBD but with a weaker effect on sleep-wake transitions. Propofol caused significant changes in protein expressions and redox state, which were effectively reversed by CBD treatment. CONCLUSIONS CBD can improve sleep structure and circadian rhythm in rats with propofol-induced sleep disorder possibly by regulating hypothalamic expressions of the key circadian clock proteins, suggesting a new treatment option for perioperative sleep disorders.
Animals ; Rats, Sprague-Dawley ; Male ; Cannabidiol/therapeutic use* ; Rats ; Circadian Rhythm/drug effects* ; Propofol/adverse effects* ; Anesthesia, General/adverse effects* ; Sleep Wake Disorders/chemically induced* ; Hypothalamus/metabolism* ; Electroencephalography

OBJECTIVES: To investigate the regulatory role of astrocytes in the dorsomedial hypothalamus (DMH) during sevoflurane anesthesia emergence. METHODS: Forty-two male C57BL/6 mice were randomized into 6 groups (n=7) for assessing astrocyte activation in the dorsomedial hypothalamus (DMH) under sevoflurane anesthesia. Two groups of mice received microinjection of agfaABC1D promoter-driven AAV2 vector into the DMH for GCaMP6 overexpression, and the changes in astrocyte activity during sevoflurane or air inhalation were recorded using calcium imaging. For assessing optogenetic activation of astrocytes, another two groups of mice received microinjection of an optogenetic virus or a control vector into the DMH with optic fiber implantation, and sevoflurane anesthesia emergence was compared using behavioral experiments. In the remaining two groups, electroencephalogram (EEG) recording during sevoflurane anesthesia emergence was conducted after injection of the hChR2-expressing and control vectors. Anesthesia induction and recovery were assessed by observing the righting reflex. EEG data were recorded under 2.0% sevoflurane to calculate the burst suppression ratio (BSR) and under 1.5% sevoflurane for power spectrum analysis. Immunofluorescence staining was performed to visualize the colocalization of GFAP-positive astrocytes with viral protein signals. RESULTS: Astrocyte activity in the DMH decreased progressively as sevoflurane concentration increased. During 2.0% sevoflurane anesthesia, the mice injected with the ChR2-expressing virus exhibited a significantly shortened wake-up time (P<0.05), and optogenetic activation of the DMH astrocytes led to a marked reduction in BSR (P<0.001). Under 1.5% sevoflurane anesthesia, optogenetic activation resulted in a significant increase in EEG gamma power and a significant decrease in delta power in ChR2 group (P<0.01). CONCLUSIONS Optogenetic activation of DMH astrocytes facilitates sevoflurane anesthesia emergence but does not significantly influence anesthesia induction. These findings offer new insights into the mechanisms underlying anesthesia emergence and may provide a potential target for accelerating postoperative recovery and managing anesthesia-related complications.
Animals ; Astrocytes/physiology* ; Sevoflurane ; Mice, Inbred C57BL ; Mice ; Male ; Electroencephalography ; Anesthetics, Inhalation/pharmacology* ; Hypothalamus/cytology* ; Anesthesia Recovery Period ; Methyl Ethers/pharmacology*