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1.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(5): 476-480, 2024 May 15.
Article in Chinese | MEDLINE | ID: mdl-38802907

ABSTRACT

OBJECTIVES: To investigate the control status of bronchial asthma (referred to as "asthma") in school-age children with normal pulmonary ventilation function and the occurrence of acute attacks within 1 year of follow-up. METHODS: A retrospective analysis was conducted on clinical data of 327 children aged 6-14 years with bronchial asthma and normal pulmonary ventilation function from April to September 2021. Based on the measured value of one second rate (FEV1/FVC), the children were divided into the ≥80% group (267 cases) and the <80% group (60 cases). The pulmonary ventilation function, asthma control level, and occurrence of acute attacks within 1 year were compared between the two groups. RESULTS: The baseline pulmonary ventilation function in the <80% group was lower than that in the ≥80% group, and the proportion of small airway dysfunction was higher than that in the ≥80% group (P<0.05). After standardized treatment for 1 year, the small airway function indices in the <80% group improved but remained lower than those in the ≥80% group (P<0.05). The rate of incomplete asthma control at baseline was 34.6% (113/327), and the asthma control level in the <80% group was lower than that in the ≥80% group (P<0.05). After standardized treatment for 1 year, the asthma control level in the <80% group remained lower than that in the ≥80% group, and the proportion of acute asthma attacks was higher than that in the ≥80% group (P<0.05). CONCLUSIONS: Approximately one-third of school-age children with asthma still have incomplete asthma control when their pulmonary ventilation function is normal. Among them, children with measured FEV1/FVC<80% have an increased risk of acute asthma attacks and require close follow-up and strengthened asthma management.


Subject(s)
Asthma , Humans , Child , Asthma/physiopathology , Asthma/therapy , Male , Female , Adolescent , Retrospective Studies , Follow-Up Studies , Pulmonary Ventilation , Acute Disease , Respiratory Function Tests
2.
PeerJ ; 12: e16997, 2024.
Article in English | MEDLINE | ID: mdl-38435993

ABSTRACT

Background: Although head elevation is an early first-line treatment for elevated intracranial pressure (ICP), the use of the head-down or prone position in managing neurocritical patients is controversial because a change in a position directly affects the intracranial and cerebral perfusion pressure, which may cause secondary brain injury and affect patient outcomes. This study compared the effects of two postural drainage positions (30° head-up tilt and 0° head flat) on the prognosis of neurocritical care patients with complicated pneumonia and a clinical pulmonary infection score (CPIS) ≥5 points to provide a reference for selecting appropriate postural drainage positions for patients with pneumonia in neurocritical care units. Methods: A prospective randomized controlled study was conducted with 62 neurocritical care patients with complicated pneumonia. The patients were categorized into control (=31) and experimental (=31) groups in a 1:1 ratio using a simple randomized non-homologous pairing method. Emphasis was placed on matching the baseline characteristics of the two groups, including patient age, sex, height, weight, Glasgow Coma Scale score, heart rate, mean arterial pressure, cough reflex, and mechanical ventilation usage to ensure comparability. Both groups received bundled care for artificial airway management. The control group maintained a standard postural drainage position of 0° head-flat, whereas the experimental group maintained a 30° head-up tilt. The efficacy of the nursing intervention was evaluated by comparing the CPIS and other therapeutic indicators between the two groups after postural drainage. Results: After the intervention, the within-group comparison showed a significant decrease in the CPIS (P < 0.001); procalcitonin levels showed a significant decreasing trend (P < 0.05); the arterial oxygen pressure significantly increased (P < 0.05); the oxygenation index significantly increased (P < 0.001); and the aspiration risk score showed a significant decreasing trend (P < 0.001). A between-group comparison showed no significant differences in any of the indicators before and after the intervention (P < 0.05). Conclusion: Postural drainage positions of 30° head-up tilt and 0° head-flat can improve the CPIS and oxygenation in patients without adverse effects. Therefore, we recommend that patients under neurological intensive care and having pneumonia be drained in a 30° head-up tilt position with good centralized care of the lung infection. Trial registration: The study, "Study of Angles of Postural Drainage in Neurocritical Patients with Pneumonia," was registered in the Protocol Registration Data Element Definitions for Interventional Study database (# ChiCTR2100042155); date of registration: 2021-01-14.


Subject(s)
Pneumonia , Humans , Prospective Studies , Pneumonia/complications , Drainage, Postural , Oxygen , Airway Management
3.
Oncol Lett ; 26(5): 462, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37780545

ABSTRACT

Growth differentiation factor 15 (GDF15), a member of the transforming growth factor-ß family, is a stress-induced cytokine. Under normal circumstances, the expression of GDF15 is low in most tissues. It is highly expressed during tissue injury, inflammation, oxidative stress and cancer. GDF15 has been established as a biomarker in patients with cancer, and is associated with cancer cachexia (CC) and poor survival. CC is a multifactorial metabolic disorder characterized by severe muscle and adipose tissue atrophy, loss of appetite, anemia and bone loss. Cachexia leads to reductions in quality of life and tolerance to anticancer therapy, and results in a poor prognosis in cancer patients. Dysregulated GDF15 levels have been discovered in patients with CC and animal models, where they have been found to be involved in anorexia and weight loss. Although studies have suggested that GDF15 mediates anorexia and weight loss in CC through its neuroreceptor, glial cell-lineage neurotrophic factor family receptor α-like, the effects of GDF15 on CC and the potential regulatory mechanisms require further elucidation. In the present review, the characteristics of GDF15 and its roles and molecular mechanisms in CC are elaborated. The targeting of GDF15 as a potential therapeutic strategy for CC is also discussed.

4.
Sci Rep ; 13(1): 18447, 2023 Oct 27.
Article in English | MEDLINE | ID: mdl-37891187

ABSTRACT

It is essential to predict carbon prices precisely in order to reduce CO2 emissions and mitigate global warming. As a solution to the limitations of a single machine learning model that has insufficient forecasting capability in the carbon price prediction problem, a carbon price prediction model (GWO-XGBOOST-CEEMDAN) based on the combination of grey wolf optimizer (GWO), extreme gradient boosting (XGBOOST), and complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) is put forward in this paper. First, a random forest (RF) method is employed to screen the primary carbon price indicators and determine the main influencing factors. Second, the GWO-XGBOOST model is established, and the GWO algorithm is utilized to optimize the XGBOOST model parameters. Finally, the residual series of the GWO-XGBOOST model are decomposed and corrected using the CEEMDAN method to produce the GWO-XGBOOST-CEEMDAN model. Three carbon emission trading markets, Guangdong, Hubei, and Fujian, were experimentally predicted to verify the model's validity. Based on the experimental results, it has been demonstrated that the proposed hybrid model has enhanced prediction precision compared to the comparison model, providing an effective experimental method for the prediction of future carbon prices.

5.
Entropy (Basel) ; 25(5)2023 Apr 26.
Article in English | MEDLINE | ID: mdl-37238474

ABSTRACT

We combined an inverse engineering technique based on Lagrange mechanics and optimal control theory to design an optimal trajectory that can transport a cartpole in a fast and stable way. For classical control, we used the relative displacement between the ball and the trolley as the controller to study the anharmonic effect of the cartpole. Under this constraint, we used the time minimization principle in optimal control theory to find the optimal trajectory, and the solution of time minimization is the bang-bang form, which ensures that the pendulum is in a vertical upward position at the initial and the final moments and oscillates in a small angle range.

6.
IEEE Trans Cybern ; 53(7): 4320-4333, 2023 Jul.
Article in English | MEDLINE | ID: mdl-35486569

ABSTRACT

The problem of fixed-time (FXT) and preassigned-time (PAT) optimization is concerned in this article based on multiagent systems (MASs) and power-law algorithms. Under the framework of strong convexity of the cost functions, two types of piecewise algorithms are proposed, which ensure that the FXT optimization can be solved either by first achieving the FXT consensus or by first achieving local optimization. Correspondingly, the PAT optimization problem is also considered by designing several piecewise protocols, where the finished time of optimization can be arbitrary prescribed according to actual demands. Furthermore, these piecewise power-law algorithms on the weighted undirected graphs are generalized to the weighted digraphs. Finally, by providing two numerical examples, the presented algorithms are further verified.

7.
Drug Deliv ; 29(1): 792-806, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35261298

ABSTRACT

Nanomedicine delivery systems can achieve precise drug delivery and reduce toxic side effects compared with traditional drug delivery methods, but further development is still needed to eliminate obstacles such as multiple drug co-delivery, uncontrolled drug-release, and drug-resistance. Herein, we designed a dual drug-loaded nanosystem (THCD-NPs) that selectively transports and targets tumor cells for the treatment of liver cancer. In this drug delivery system, hyaluronic acid (HA)-conjugated curcumin (Cur) and d-α-tocopherol acid polyethylene glycolsuccinate (TPGS) were used as selective drug-carrying vehicles to deliver dasatinib (DAS) to cancer cells for combined administration. The mean size of the nanoparticles was approximately 66.14 ± 4.02 nm with good in vitro stability. The nanoparticles were pH sensitive and could accelerate drug release at low pH conditions. In vitro experiments showed that THCD-NPs were significantly cytotoxic to HepG2 cells and could be effectively taken up by these cells. Detailed investigations also demonstrated its pro-apoptotic activity. In vivo NIR fluorescence imaging showed that the nanoparticles could accumulate efficiently at the tumor site. Meanwhile, in vivo experiments showed that THCD-NPs significantly inhibited tumor growth and reduced the toxic side effects of free drugs in a mouse solid tumor model. In short, the nanoparticles we prepared provide a new idea for the treatment of liver cancer.


Subject(s)
Curcumin , Liver Neoplasms , Nanoparticles , Animals , Cell Line, Tumor , Curcumin/pharmacology , Curcumin/therapeutic use , Dasatinib/pharmacology , Drug Carriers , Drug Delivery Systems/methods , Drug Liberation , Hydrogen-Ion Concentration , Liver Neoplasms/drug therapy , Mice , Micelles , Nanoparticles/therapeutic use
8.
Comput Math Methods Med ; 2022: 9380796, 2022.
Article in English | MEDLINE | ID: mdl-38550528

ABSTRACT

Background: Peripherally inserted central catheter (PICC) is the most commonly used infusion route for chemotherapy in Chinese breast cancer patients because of its convenience, ease of operation, and many maintenance sites. Objective: The objective of this study is to investigate the effect of the first dressing change time on the healing of puncture site and the economic and psychological impact in patients with breast cancer after PICC insertion. Methods: From April 2020 to October 2020, 120 patients with PICC intubation after breast cancer surgery were selected as the research objects and divided into test group and the control group with 60 cases in each group according to the random number table method. The time of the first dressing change in the control group was routinely performed within 24 hours after PICC catheter placement, while the first dressing change in test group was performed at 48 hours after catheter placement. The effect of the first dressing change time after PICC catheterization on patients after breast cancer surgery was compared between the two groups. Results: There were significant differences between the two groups in the degree of pain after the first dressing change, the degree of oozing at the puncture site within 1 week, the duration of oozing, and the frequency of maintenance within 3 weeks, cost, depression, and anxiety (P < 0.05). Conclusion: The first dressing change 48 hours after PICC cauterization in patients after breast cancer surgery reduces significantly puncture site bleeding, reduces the frequency of dressing change, and benefits the physical and mental health of patients.

9.
Am J Transl Res ; 13(12): 13768-13775, 2021.
Article in English | MEDLINE | ID: mdl-35035715

ABSTRACT

OBJECTIVE: To investigate the effect of cognitive behavioral therapy (CBT) and WeChat-based health education on patients underwent peripherally inserted central catheter (PICC) line placement. METHODS: The clinical data of 113 patients with PICC line placement in our hospital from January 2019 to January 2021 were retrospectively collected and the patients were divided into two groups according to the intervention methods. Group A (n=56) received routine care of PICC line placement, while group B (n=57) received CBT and WeChat-based health education. The social support, Self-rating Anxiety Scale (SAS) scores, Self-rating Depression Scale (SDS) scores, Quality of Life Scale (QLQ-C30) scores, catheter care compliance, complications and score of self-care ability were compared between the two groups before and after intervention. RESULTS: After intervention, group B had higher social support utilization, subjective and objective support scores, social support scores, quality of life scores, lower SAS and SDS scores, and higher catheter maintenance compliance than group A (P < 0.05). The complication rate was 3.51% in group B, which was significantly lower than 25.00% in group A (P < 0.05). The score of self-care ability in group B was higher than that in group A after intervention (P < 0.05). CONCLUSION: CBT and WeChat-based health education have significant effects on improving patients' catheter maintenance compliance, score of self-care ability, social support and quality of life, which can alleviate dysphoria and reduce the incidence of complications.

10.
Hear Res ; 391: 107957, 2020 06.
Article in English | MEDLINE | ID: mdl-32278945

ABSTRACT

We examined the effect of acoustic trauma on the spontaneous activities of the glutamatergic and GABAergic neurons in the inferior colliculus (IC) of mice. Optogenetics was used to identify the neuron type. In control animals, the spontaneous firing rate was higher in GABAergic neurons than in glutamatergic neurons. However, in the animals with acoustic trauma, the balance of spontaneous activities between glutamatergic and GABAergic neurons was inverted. The spontaneous firing rate was enhanced in glutamatergic neurons only, with bursting episodes occurring frequently. Moreover, the spike shapes of GABAergic and glutamatergic neurons were modified differently in both cell types. These results suggested that the acoustic trauma induced plastic changes in the neuronal circuits in the IC and altered the balance of the activities of excitatory and inhibitory neurons. This aberrant excitatory-inhibitory balance in the IC might underpin tinnitus perception.


Subject(s)
GABAergic Neurons/metabolism , Glutamic Acid/metabolism , Hearing Loss, Noise-Induced/metabolism , Inferior Colliculi/metabolism , Neural Inhibition , Neuronal Plasticity , Synaptic Transmission , Animals , Disease Models, Animal , Evoked Potentials, Auditory, Brain Stem , Female , GABAergic Neurons/pathology , Hearing Loss, Noise-Induced/etiology , Hearing Loss, Noise-Induced/pathology , Hearing Loss, Noise-Induced/physiopathology , Inferior Colliculi/pathology , Inferior Colliculi/physiopathology , Male , Mice, Inbred C57BL , Mice, Transgenic , Noise
11.
Sci Rep ; 10(1): 5666, 2020 Mar 24.
Article in English | MEDLINE | ID: mdl-32205855

ABSTRACT

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

12.
Sci Rep ; 10(1): 2611, 2020 02 13.
Article in English | MEDLINE | ID: mdl-32054964

ABSTRACT

The antioxidant activities of 18 typical phenolic acids were investigated using 2, 2'-diphenyl-1-picrylhydrazyl (DPPH) and ferric ion reducing antioxidant power (FRAP) assays. Five thermodynamic parameters involving hydrogen atom transfer (HAT), single-electron transfer followed by proton transfer (SET-PT), and sequential proton-loss electron transfer (SPLET) mechanisms were calculated using density functional theory with the B3LYP/UB3LYP functional and 6-311++G (d, p) basis set and compared in the phenolic acids. Based on the same substituents on the benzene ring, -CH2COOH and -CH = CHCOOH can enhance the antioxidant activities of phenolic acids, compared with -COOH. Methoxyl (-OCH3) and phenolic hydroxyl (-OH) groups can also promote the antioxidant activities of phenolic acids. These results relate to the O-H bond dissociation enthalpy of the phenolic hydroxyl group in phenolic acids and the values of proton affinity and electron transfer enthalpy (ETE) involved in the electron donation ability of functional groups. In addition, we speculated that HAT, SET-PT, and SPLET mechanisms may occur in the DPPH reaction system. Whereas SPLET was the main reaction mechanism in the FRAP system, because, except for 4-hydroxyphenyl acid, the ETE values of the phenolic acids in water were consistent with the experimental results.

13.
J Neurophysiol ; 121(3): 785-798, 2019 03 01.
Article in English | MEDLINE | ID: mdl-30649979

ABSTRACT

Discriminating biologically relevant sounds is crucial for survival. The neurophysiological mechanisms that mediate this process must register both the reward significance and the physical parameters of acoustic stimuli. Previous experiments have revealed that the primary function of the auditory cortex (AC) is to provide a neural representation of the acoustic parameters of sound stimuli. However, how the brain associates acoustic signals with reward remains unresolved. The amygdala (AMY) and medial prefrontal cortex (mPFC) play keys role in emotion and learning, but it is unknown whether AMY and mPFC neurons are involved in sound discrimination or how the roles of AMY and mPFC neurons differ from those of AC neurons. To examine this, we recorded neural activity in the primary auditory cortex (A1), AMY, and mPFC of cats while they performed a Go/No-go task to discriminate sounds with different temporal patterns. We found that the activity of A1 neurons faithfully coded the temporal patterns of sound stimuli; this activity was not affected by the cats' behavioral choices. The neural representation of stimulus patterns decreased in the AMY, but the neural activity increased when the cats were preparing to discriminate the sound stimuli and waiting for reward. Neural activity in the mPFC did not represent sound patterns, but it showed a clear association with reward and was modulated by the cats' behavioral choices. Our results indicate that the initial auditory representation in A1 is gradually transformed into a stimulus-reward association in the AMY and mPFC to ultimately generate a behavioral choice. NEW & NOTEWORTHY We compared the characteristics of neural activities of primary auditory cortex (A1), amygdala (AMY), and medial prefrontal cortex (mPFC) while cats were performing the same auditory discrimination task. Our results show that there is a gradual transformation of the neural code from a faithful temporal representation of the stimulus in A1, which is insensitive to behavioral choices, to an association with the predictive reward in AMY and mPFC, which, to some extent, is correlated with the animal's behavioral choice.


Subject(s)
Amygdala/physiology , Auditory Cortex/physiology , Auditory Perception , Discrimination, Psychological , Neurons/physiology , Prefrontal Cortex/physiology , Amygdala/cytology , Animals , Auditory Cortex/cytology , Cats , Choice Behavior , Male , Prefrontal Cortex/cytology , Reward
14.
J Vis Exp ; (136)2018 06 28.
Article in English | MEDLINE | ID: mdl-30010633

ABSTRACT

It is a major concern in neuroscience how different types of neurons work in neural circuits. Recent advances in optogenetics have enabled the identification of the neuronal type in in vivo electrophysiological experiments in broad brain regions. In optogenetics experiments, it is critical to deliver the light to the recording site. However, it is often hard to deliver the stimulation light to the deep brain regions from the brain's surface. Especially, it is difficult for the stimulation light to reach the deep brain regions when the optical transparency of the brain surface is low, as is often the case with recordings from awake animals. Here, we describe a method to record spike responses to the light from an awake mouse using a custom-made glass optrode. In this method, the light is delivered through the recording glass electrode so that it is possible to reliably stimulate the recorded neuron with light in the deep brain regions. This custom-made optrode system consists of accessible and inexpensive materials and is easy to assemble.


Subject(s)
Neurons/metabolism , Optogenetics/methods , Animals , Mice
15.
Sci Rep ; 8(1): 3683, 2018 02 27.
Article in English | MEDLINE | ID: mdl-29487299

ABSTRACT

Auditory steady state response (ASSR) and inhibitory gating (IG) are electrophysiological examinations commonly used to evaluate the sensory and cognitive functions of the brain. In some clinic examinations and animal experiments, general anesthesia is necessary to conduct electrophysiological recordings. However, the effects of anesthesia on ASSR and IG remain unclear. For this reason, we recorded local field potentials though electrodes implanted in different brain areas of rats: the auditory cortex (AC), hippocampus (HC), amygdala (AMY), and prefrontal cortex (PFC), and compared the characteristics of ASSR and IG under anesthetized and conscious conditions. We found that ASSR signals were the strongest in the AC, and decreased sequentially in the HP, AMY, and PFC. Chloral hydrate anesthesia significantly reduced the power and phase-locking of ASSR in the AC, HP, and AMY. In contrast, the extent of IG in the AC was weakest and it increased sequentially in the HP, AMY, and PFC. Anesthesia had less effect on the extent of IG. Our results suggest that ASSR and IG may originate from different neural circuits and that IG is more resistant to general anesthesia and therefore better suited to examining the functioning of non-auditory brain regions.


Subject(s)
Anesthesia, General/methods , Chloral Hydrate/therapeutic use , Amygdala/drug effects , Animals , Auditory Cortex/drug effects , Evoked Potentials, Auditory/drug effects , Hippocampus/drug effects , Male , Prefrontal Cortex/drug effects , Rats , Rats, Wistar
16.
PLoS One ; 13(2): e0192103, 2018.
Article in English | MEDLINE | ID: mdl-29415081

ABSTRACT

Auditory steady-state responses (ASSRs) represent the electrophysiological activity of the auditory nervous system in response to a periodic acoustic stimulus. Spectrogram analysis can reveal the frequency and phase information entrained in ASSRs. Clinically, the ASSR is used to detect abnormalities in electroencephalographs obtained from schizophrenia patients, who show reduced power and phase locking of ASSRs. The neonatal ventral hippocampal lesion (NVHL) rat is a widely used model to investigate the neurodevelopmental mechanisms of schizophrenia. It has been established that NVHL rats exhibit several schizophrenia-like behavioral and molecular abnormalities. However, no clear abnormalities in ASSRs have been reported to date. The present study compared ASSRs of adult NVHL and sham-operated rats. We inserted microelectrodes into the primary auditory cortex (A1) or posterior auditory field (PAF) and recorded the local field potential (LFP) in response to 40- and 80-Hz click train stimuli. Spectrogram analysis was performed to obtain the mean trial power (MTP) and phase-locking factor (PLF) of the click train-evoked LFPs. We found that in the control animals, A1 showed a stronger MTP and PLF of ASSR than PAF, and NVHL operation mainly impaired the ASSR in PAF. Analysis of spike activity also indicated that NVHL operation extended the duration of tone-evoked responses in PAF neurons. Our results reveal, for the first time, that NVHL may distinctly influence the neural activities of primary and non-primary fields of the auditory cortex.


Subject(s)
Acoustic Stimulation/methods , Auditory Cortex/physiopathology , Hippocampus/pathology , Animals , Animals, Newborn , Auditory Cortex/pathology , Calibration , Female , Male , Pregnancy , Rats , Rats, Sprague-Dawley , Reflex, Startle
17.
Stress ; 20(3): 312-319, 2017 05.
Article in English | MEDLINE | ID: mdl-28446047

ABSTRACT

A fundamental adaptive mechanism of auditory function is inhibitory gating (IG), which refers to the attenuation of neural responses to repeated sound stimuli. IG is drastically impaired in individuals with emotional and cognitive impairments (i.e. posttraumatic stress disorder). The objective of this study was to test whether chronic stress impairs the IG of the auditory cortex (AC). We used the standard two-tone stimulus paradigm and examined the parametric qualities of IG in the AC of rats by recording the electrophysiological signals of a single-unit and local field potential (LFP) simultaneously. The main results of this study were that most of the AC neurons showed a weaker response to the second tone than to the first tone, reflecting an IG of the repeated input. A fast negative wave of LFP showed consistent IG across the sampled AC sites, whereas a slow positive wave of LFP had less IG effect. IG was diminished following chronic restraint stress at both, the single-unit and LFP level, due to the increase in response to the second tone. This study provided new evidence that chronic stress disrupts the physiological function of the AC. Lay Summary The effects of chronic stress on IG were investigated by recording both, single-unit spike and LFP activities, in the AC of rats. In normal rats, most of the single-unit and N25 LFP activities in the AC showed an IG effect. IG was diminished following chronic restraint stress at both, the single-unit and LFP level.


Subject(s)
Auditory Cortex/physiopathology , Evoked Potentials, Auditory/physiology , Neural Inhibition/physiology , Neurons/physiology , Stress, Psychological/physiopathology , Acoustic Stimulation/methods , Animals , Electroencephalography , Male , Rats , Restraint, Physical
18.
Sci Rep ; 7(1): 677, 2017 04 06.
Article in English | MEDLINE | ID: mdl-28386101

ABSTRACT

The relationship between attention and sensory coding is an area of active investigation. Previous studies have revealed that an animal's behavioral state can play a crucial role in shaping the characteristics of neural responses in the auditory cortex (AC). However, behavioral modulation of auditory response in brain areas outside the AC is not well studied. In this study, we used the same experimental paradigm to examine the effects of attention on neural activity in multiple brain regions including the primary auditory cortex (A1), posterior auditory field (PAF), amygdala (AMY), and striatum (STR). Single-unit spike activity was recorded while cats were actively performing a tone-detection task or passively listening to the same tones. We found that tone-evoked neural responses in A1 were not significantly affected by task-engagement; however, those in PAF and AMY were enhanced, and those in STR were suppressed. The enhanced effect was associated with an improvement of accuracy of tone detection, which was estimated from the spike activity. Additionally, the firing rates of A1 and PAF neurons decreased upon motor response (licking) during the detection task. Our results suggest that attention may have different effects on auditory responsive brain areas depending on their physiological functions.


Subject(s)
Acoustic Stimulation , Amygdala/physiology , Auditory Cortex/physiology , Auditory Perception/physiology , Corpus Striatum/physiology , Animals , Brain Mapping , Cats , Evoked Potentials, Auditory , Magnetic Resonance Imaging/methods , Neurons/physiology , Reaction Time
19.
20.
Front Syst Neurosci ; 9: 61, 2015.
Article in English | MEDLINE | ID: mdl-25964744

ABSTRACT

Although neural responses to sound stimuli have been thoroughly investigated in various areas of the auditory cortex, the results electrophysiological recordings cannot establish a causal link between neural activation and brain function. Electrical microstimulation, which can selectively perturb neural activity in specific parts of the nervous system, is an important tool for exploring the organization and function of brain circuitry. To date, the studies describing the behavioral effects of electrical stimulation have largely been conducted in the primary auditory cortex. In this study, to investigate the potential differences in the effects of electrical stimulation on different cortical areas, we measured the behavioral performance of cats in detecting intra-cortical microstimulation (ICMS) delivered in the primary and secondary auditory fields (A1 and A2, respectively). After being trained to perform a Go/No-Go task cued by sounds, we found that cats could also learn to perform the task cued by ICMS; furthermore, the detection of the ICMS was similarly sensitive in A1 and A2. Presenting wideband noise together with ICMS substantially decreased the performance of cats in detecting ICMS in A1 and A2, consistent with a noise masking effect on the sensation elicited by the ICMS. In contrast, presenting ICMS with pure-tones in the spectral receptive field of the electrode-implanted cortical site reduced ICMS detection performance in A1 but not A2. Therefore, activation of A1 and A2 neurons may produce different qualities of sensation. Overall, our study revealed that ICMS-induced neural activity could be easily integrated into an animal's behavioral decision process and had an implication for the development of cortical auditory prosthetics.

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