Executive function deficits in patients with the first episode of late-life depression before and after SSRI treatment: A pilot fMRI study.

BACKGROUND: Executive function deficits (EFD) in late-life depression (LLD) has been reported to be associated with antidepressant treatment resistance, increased disability, and poor quality of life. However, the underlying neutral mechanisms of EFD in patients with the first episode of LLD remains unclear. METHODS: A total of 27 patients with first-episode, drug-naive LLD and 27 non-depressed controls (NC) were recruited for the present research. Participants underwent the Trail Making Test, the 17-item Hamilton depression rating scale (HAMD-17) test, and task-state functional magnetic resonance imaging scans under the neutral Stroop task. LLD patients' executive functions, depressive symptoms, and brain activity were examined again after 6 months of antidepressant treatment. RESULTS: Of the 27 LLD patients, 16 cases completed 6-month follow-ups. Patients in the LLD baseline group spent more time on the Trail Making Test A test than those in the NC group (p < 0.05). In the presence of an incongruency between the word color and meaning, the accuracy rate of the neutral Stroop task in the LLD baseline group was lower, and the reaction time was greater than that in the NC group, with statistically significant difference (p < 0.05). The HAMD-17 score in the LLD follow-up group was significantly lower than that in the LLD baseline group (p < 0.05). More activated brain regions were present in the LLD baseline group than in the NC group when performing the neutral Stroop task. Compared with the LLD baseline group, abnormal activation of relevant brains in the cingulate-prefrontal-parietal network of LLD patients still existed in the LLD follow-up group. CONCLUSIONS: LLD patients engaged more brain areas than the NC group while performing the neutral Stroop task. Abnormal activation of the cingulate-prefrontal-parietal network could be a contributing factor to EFD in LLD. TRIAL REGISTRATION: ChiCTR, ChiCTR2100042370 (Date of registration: 21/01/2021). LIMITS: We didn't enroll enough first-episode, LLD patients, the robustness of the findings need to be confirmed by large sample clinical trials.

An unusual case of reactivated latent pulmonary cryptococcal infection in a patient after short-term steroid and azathioprine therapy: a case report.

BACKGROUND: Cryptococcus is one of the major fungal pathogens infecting the lungs. Pulmonary cryptococcal infection is generally considered a community-acquired condition caused by inhalation of dust contaminated with fungal cells from the environment. Here, we report a case developing pulmonary cryptococcosis 3 months after hospital admission, which has rarely been reported before. CASE PRESENTATION: A 73-year-old female patient who was previously immunocompetent experienced persistent dry cough for 2 weeks, 3 months after admission. Chest computed tomography (CT) showed a new solitary pulmonary nodule developed in the upper lobe of the left lung. Staining and culture of expectorated sputum smears were negative for bacteria, acid-fast bacilli, or fungus. The patient then underwent biopsy of the lesion. Histopathology findings and a positive serum cryptococcal antigen titer (1:8) indicated pulmonary cryptococcosis. Daily intravenous 400 mg fluconazole was administered initially followed by oral fluconazole therapy. Follow-up chest CT after 3 months of antifungal therapy showed complete disappearance of the pulmonary nodule. Respiratory symptoms of the patient also resolved. A complete investigation excluded the possibility of a patient-to-patient transmission or primarily acquiring the infection from the hospital environment. Based on the patient's history of exposure to pigeons before admission and recent steroid and azathioprine use after admission for the treatment of myasthenic crisis, reactivation of a latent pulmonary cryptococcal infection acquired before admission, in this case, is impressed. CONCLUSIONS: Although rarely reported, pulmonary cryptococcal infection should be included in the differential diagnosis of hospitalized patients with respiratory symptoms, especially in those with predisposing risk factors. Chest image studies and further surgical biopsy are needed for confirmation.

Repetitive Transcranial Magnetic Stimulation for Working Memory Deficits in Schizophrenia: A Systematic Review of Randomized Controlled Trials.

Working memory (WM) deficits are a significant component of neurocognitive impairment in individuals with schizophrenia (SCZ). Two previous meta-analyses, conducted on randomized controlled trials (RCTs), examined the effectiveness of repetitive transcranial magnetic stimulation (rTMS) in addressing WM deficits in individuals diagnosed with SCZ. However, the conclusions drawn from these analyses were inconsistent. Additionally, the commonly used random effects (RE) models might underestimate statistical errors, attributing a significant portion of perceived heterogeneity between studies to variations in study quality. Therefore, this review utilized both RE and quality effects (QE) models to assess relevant RCTs comparing TMS with sham intervention in terms of clinical outcomes. A comprehensive literature search was conducted using PubMed and Scopus databases, resulting in the inclusion of 13 studies for data synthesis. Overall, regardless of whether the RE or QE model was used, eligible RCTs suggested that the TMS and sham groups exhibited comparable therapeutic effects after treatment. The current state of research regarding the use of rTMS as a treatment for WM deficits in patients with SCZ remains in its preliminary phase. Furthermore, concerning the mechanism of action, the activation of brain regions focused on the dorsolateral prefrontal cortex and alterations in gamma oscillations may hold significant relevance in the therapeutic application of rTMS for addressing WM impairments. Finally, we believe that the application of closed-loop neuromodulation may contribute to the optimization of rTMS for WM impairment in patients with SCZ.

Trial-by-Trial Variability of TMS-EEG in Healthy Controls and Patients With Depressive Disorder.

Depressive disorder has been known to be associated with high variability in resting-state electroencephalography (EEG) signals. However, this phenomenon is often ignored in stimulus-related brain activities. This study proposed a new method to explore the EEG variability evoked by transcranial magnetic stimulation (TMS, TMS-EEG) in depressive disorder (DE) patients. The TMS-EEG data were collected from 34 DE patients and 36 healthy controls (HC). The maximum eigenvalue of the real binary correlation matrix, calculated between different trials using cross-correlation and surrogate methods, was extracted to assess trial-by-trial variability (TTV) of TMS-EEG. The new method was found to more sensitive and reliable than the standard deviation method. DE patients exhibited significantly smaller TTV in Gamma band and greater TTV in Delta band than HC. Furthermore, the HAMD-17 scores were negatively correlated with TTV values in Gamma band. This study represented the first investigation into the TTV in TMS-EEG data and revealed abnormal values in DE patients. Those findings enhance our understanding of TMS-EEG technology and provide valuable insights for studying the characteristics of DE.

Subregional thalamic functional connectivity abnormalities and cognitive impairments in first-episode schizophrenia.

BACKGROUND: Previous studies have documented thalamic functional connectivity (FC) abnormalities in schizophrenia, typically examining the thalamus as a whole. The specific link between subregional thalamic FC and cognitive deficits in first-episode schizophrenia (FES) remains unexplored. METHODS: Using data from resting-state functional magnetic resonance imaging, we compared whole-brain FC with thalamic subregions between patients and HCs, and analyzed FC changes in drug-naïve patients separately. We then examined correlations between FC abnormalities with both cognitive impairment and clinical symptoms. RESULTS: A total of 33 FES patients (20 drug-naïve) and 32 age- and sex-matched healthy controls (HCs) were included. Compared to HCs, FES patients exhibited increased FC between specific thalamic subregions and cortical regions, particularly bilateral middle temporal lobe and cuneus gyrus, left medial superior frontal gyrus, and right inferior/superior occipital gyrus. Decreased FC was observed between certain thalamic subregions and the left inferior frontal triangle. These findings were largely consistent in drug-naïve patients. Notably, deficits in social cognition and visual learning in FES patients correlated with increased FC between certain thalamic subregions and cortical regions involving the right superior occipital gyrus and cuneus gyrus. The severity of negative symptoms was associated with increased FC between a thalamic subregion and the left middle temporal gyrus. CONCLUSION: Our findings suggest FC abnormalities between thalamic subregions and cortical areas in FES patients. Increased FC correlated with cognitive deficits and negative symptoms, highlighting the importance of thalamo-cortical connectivity in the pathophysiology of schizophrenia.

Individualized prediction of cognitive test scores from functional brain connectome in patients with first-episode late-life depression.

BACKGROUND: In the realm of cognitive screening, the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) are widely utilized for detecting cognitive deficits in patients with late-life depression (LLD), However, the interindividual variability in neuroimaging biomarkers contributing to individual-specific symptom severity remains poorly understood. In this study, we used a connectome-based predictive model (CPM) approach on resting-state functional magnetic resonance imaging data from patients with LLD to establish individualized prediction models for the MoCA and the MMSE scores. METHODS: We recruited 135 individuals diagnosed with first-episode LLD for this research. Participants underwent the MMSE and MoCA tests, along with resting-state functional magnetic resonance imaging scans. Functional connectivity matrices derived from these scans were utilized in CPM models to predict MMSE or MoCA scores. Predictive precision was assessed by correlating predicted and observed scores, with the significance of prediction performance evaluated through a permutation test. RESULTS: The negative model of the CPM procedure demonstrated a significant capacity to predict MoCA scores (r = -0.309, p = 0.002). Similarly, the CPM procedure could predict MMSE scores (r = -0.236, p = 0.016). The predictive models for cognitive test scores in LLD primarily involved the visual network, somatomotor network, dorsal attention network, and ventral attention network. CONCLUSIONS: Brain functional connectivity emerges as a promising predictor of personalized cognitive test scores in LLD, suggesting that functional connectomes are potential neurobiological markers for cognitive performance in patients with LLD.

More proactive but less efficient: The effect of trait self-control on emotion regulation and its neural mechanisms.

Self-control is important for maintaining good health, acquiring achievement and happiness, and improving environmental adaptability. Trait self-control can affect the processing of emotional conflict in daily life and is associated with successful emotional regulation. In this study, the task functional magnetic resonance imaging (fMRI) technology was adopted to explore the emotion regulation processing and neural mechanism of individuals with different trait self-control levels. The results showed that: (a) Individuals with high self-control experienced the lower intensity of negative emotion when viewing negative emotional pictures than individuals with low self-control, showing spontaneous emotion regulation and significantly increased activity of executive control and emotion regulation networks of the brain; (b) Individuals with low self-control were more sensitive to negative emotion, and their emotion regulation effect under external instructions was better than that of individuals with high self-control. This suggests that individuals with high trait self-control were adept at using proactive control strategies to spontaneously regulate emotional conflict and experienced less emotional conflict accordingly. However, they were less effective than low self-control individuals in resolving emotional conflicts. These findings provide an important basis for our understanding of the nature and neural mechanism of self-control.

Self-control mediates the relationship between time perspective and mobile phone addiction in Chinese college students.

Background: Mobile phone addiction (MPA) is a prevalent problem among college students, and Chinese college students are a high-risk group for smartphone addiction. MPA has a negative impact on the physical and mental health and academic performance of college students. Studies have explored the influence of many factors on MPA, such as the characteristics of the smartphone itself, the characteristics of the smartphone user, and the environment. However, to date, no studies have explored the protective and risk factors for MPA from the perspective of personality traits. From this perspective, this study explored the influence of time perspective and trait self-control on MPA to identify effective measures to prevent and intervene in MPA in college students. Methods: The participants in this cross-sectional study were 526 Chinese college students. They completed the Zimbardo Time Perspective Inventory, the Self-Control Scale and the Mobile Phone Addiction Tendency Scale using an online questionnaire tool. Pearson correlation analysis was used to explore the relationships among time perspective, self-control and MPA. A latent variable mediation analysis of the structural equation model was used to examine the mediating role of self-control in the relationship between time perspective and MPA. Results: Various dimensions of time perspective were strongly associated with MPA. Among these dimensions, past negative (r = 0.397, p < 0.001), present hedonistic (r = 0.207, p < 0.001), and present fatalistic perspectives (r = 0.444, p < 0.001) were positively associated with MPA, while a future time perspective (r = -0.200, p < 0.001) was negatively associated with MPA. Mediation effects analysis showed that past negative (ß = 0.034, p < 0.001, 95% CI [0.020-0.051]), present hedonistic (ß = 0.038, p < 0.001, 95% CI [0.02-0.06]), present fatalistic (ß = 0.047, p < 0.001, 95% CI [0.031-0.065]) and future orientation perspectives (ß = -0.093, p < 0.001, 95% CI [-0.123-0.069]) indirectly influenced MPA through the mediating effect of self-control. Conclusion: This study confirmed that a future time perspective and self-control are protective factors for MPA and that past negative, present hedonistic and present fatalistic perspectives are risk factors for MPA. College educators can prevent MPA in college students directly by cultivating their self-control ability, as well as indirectly by increasing their use of future time perspective and reducing past negative, present fatalistic and present hedonistic perspectives.

Simultaneous measurement of amino acid enantiomers in the serum of late-life depression patients using convenient LC-MS/MS method with Nα-(5-fluoro-2,4-dinitrophenyl)-l-leucinamide Derivatization.

D-amino acids may be indicators of late-life depression but separation and quantification of enantiomers which differ only by optical rotation sign remain challenging due to their identical physical and chemical properties. A convenient LC-MS/MS method was developed for the simultaneous measurement of l- and d-amino acids based on the chiral derivatization reagent, Nα-(5-fluoro-2,4-dinitrophenyl)-L-leucinamide, and conventional octadecylsilane reversed-phase column. Methanol was used as the extraction solvent and a single-step derivatization reaction using volatile triethylamine eliminated the requirement for desalination prior to LC-MS/MS. Simultaneous separation and identification of 21 amino acids and the enantiomeric compositions of the 18 chiral proteogenic entities were achieved. Low limits of detection (0.03-4.0 nM), wide linear range (0.01-20 µM), good precision (RSDs < 10 %) and negligible matrix effects indicated the suitability of the method. Application of the method to the quantification of serum chiral amino acids in late-life depression patients (n = 40) and controls (n = 35) found a total of 17 L-amino acids, 14 D-amino acids, DL-asparagine, glycine and γ-aminobutyric acid. The statistical evaluation showed significant differences of glycine, L-threonine and D-methionine between late-life depression patients and controls, indicating that these are potential biomarkers of late-life depression.

Executive function deficits and medial temporal lobe atrophy in late-life depression and Alzheimer's disease: a comparative study.

Objectives: Alzheimer's disease (AD) and late-life depression (LLD) frequently exhibit executive function deficits (EFD) and medial temporal lobe atrophy (MTA) as shared characteristics. The objective of this research was to examine the utility of the Trail Making Test (TMT) and the MTA scale in distinguishing between LLD and AD. Methods: A study of 100 patients, 50 with AD and 50 with LLD, was conducted using a cross-sectional design. The individuals were subjected to clinical evaluations to assess their level of depression and overall cognitive abilities, which included the Geriatric Depression Scale (GDS), Mini-Mental State Examination (MMSE), and Montreal Cognitive Assessment (MoCA). We evaluated executive function deficits (EFD) through the use of the TMT, which includes both TMT-A and TMT-B. MTA was measured using magnetic resonance imaging. To evaluate the ability of TMT and MTA scale to distinguish between the two groups, a receiver operating characteristic (ROC) curve was utilized. To investigate the connections between MTA and neuropsychological measures, a correlation analysis was performed. Results: AD patients exhibited notably reduced MMSE, MoCA, and GDS scores, as well as an increased MTA total scores, time spent on TMT-A, and TMT-B compared to LLD patients (p < 0.05). TMT-A and TMT-B both exhibited excellent discriminatory power between AD and LLD, achieving area under curve (AUC) values of 92.2 and 94.2%, respectively. In AD patients, there was a negative correlation between MMSE and MoCA scores and MTA scores, while in LLD patients, there was a positive correlation between time spent on TMT-A and GDS scores and MTA scores. Conclusion: AD patients experience more severe EFD and MTA than LLD patients. The differential diagnosis of AD and LLD can be aided by the useful tool known as TMT. It is important to acknowledge that TMT is capable of capturing only a fraction of the executive function, thus necessitating a cautious interpretation of research findings.

Cognitive control impairment in ax-continuous performance test in patients with schizophrenia: A pilot EEG study.

OBJECTIVES: This study aimed to investigate the mechanism of cognitive control impairment in patients with schizophrenia (SPs) using electroencephalogram (EEG). METHODS: A total of 17 SPs and 17 healthy controls (HCs) were included in this study. We measured the EEG activity, whereas they performed the AX-continuous performance test which consisted of the preparatory phase and the response phase. The MATRICS Consensus Cognitive Battery (MCCB) was used for cognitive function, and the Positive and Negative Syndrome Scale (PANSS) was used for clinical symptom assessment. A univariate linear regression model was used to explore the relationships among behavioral index, event-related potentials (ERPs), rhythmic oscillation power, and score of MCCB and PANSS. RESULTS: A significant difference was found in response accuracy and reaction time (RT) during the preparatory phase between patients and HCs (p < .05). During the response phase, the SPs exhibited longer RT than the HCs (p < .05). Analysis of the ERPs revealed that the amplitude of P3a on BX clues was significantly smaller in SPs than in HCs (p < .05). Additionally, the midline frontal theta power of neural oscillation was significantly lower in the SPs than in NCs both during the preparatory and response phases. The accuracies on BX clues (r = .694, p = .002) and d'context (r = .698, p = .002) were positively correlated with MCCB scores. CONCLUSION: The present study revealed that patients with schizophrenia have deficits both in proactive and reactive cognitive control, with a greater reliance on reactive control during conflict resolution. The neural mechanisms of the cognitive control impairment may involve the inability to engage additional neural resources for proactive control, and a reduction in frontal midline theta power during both proactive and reactive control. The severity of proactive control impairment is positively correlated with an increased tendency to rely on reactive control.

Altered topological properties of functional brain networks in patients with first episode, late-life depression before and after antidepressant treatment.

Objectives: To preliminarily explore the functional activity and information integration of the brains under resting state based on graph theory in patients with first-episode, late-life depression (LLD) before and after antidepressant treatment. Methods: A total of 50 patients with first-episode LLD and 40 non-depressed controls (NCs) were recruited for the present research. Participants underwent the RBANS test, the 17-item Hamilton depression rating scale (HAMD-17) test, and resting-state functional MRI scans (rs-fMRI). The RBANS test consists of 12 sub-tests that contribute to a total score and index scores across the five domains: immediate memory, visuospatial/constructional, language, attention, and delayed memory. Escitalopram or sertraline was adopted for treating depression, and the dosage of the drug was adjusted by the experienced psychiatrists. Of the 50 LLD patients, 27 cases who completed 6-month follow-ups and 27 NCs matched with age, sex, and education level were included for the final statistical analysis. Results: There were significant differences in RBANS total score, immediate memory, visuospatial/constructional, language, attention, and delayed memory between LLD baseline group and NCs group (P < 0.05). Considering the global attribute indicators, the clustering coefficient of global indicators was lower in the LLD baseline group than in the NCs group, and the small-world attribute of functional brain networks existed in all three groups. The degree centrality and node efficiency of some brains were lower in the LLD baseline group than in the NCs group. After 6 months of antidepressant therapy, the scores of HAMD-17, immediate memory, language, and delayed memory in the LLD follow-up group were higher than those in the LLD baseline group. Compared with the LLD baseline group, the degree centrality and node efficiency of some brains in the cognitive control network were decreased in the LLD follow-up group. Conclusions: The ability to integrate and divide labor of functional brain networks declines in LLD patients and linked with the depression severity. After the relief of depressive symptoms, the small-world attribute of functional brain networks in LLD patients persists. However, the information transmission efficiency and centrality of some brain regions continue to decline over time, perhaps related to their progressive cognitive impairment.

The cognitive effects of adjunctive repetitive transcranial magnetic stimulation for late-onset depression: a randomized controlled trial with 4 week follow-up.

Objectives: Cognitive impairment is common and linked to poor outcomes in patients with late-onset depression (LOD). The cognitive effects of repetitive transcranial magnetic stimulation (rTMS) for LOD are not well understood. This study aimed to investigate the effects of rTMS on cognitive function in elderly patients with LOD. Methods: In total, 58 elderly patients (aged 60 to 75 years) with depression were enrolled and randomly assigned to an active rTMS group or a sham group. The participants received active or sham rTMS over the left dorsolateral prefrontal cortex for 4 weeks, 5 days a week, at a frequency of 10 Hz rTMS and 120% of the motor threshold (MT). Cognitive function was assessed using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) at baseline, the end of the 4 week treatment period, and at the 4 week follow-up. Results: The active rTMS group showed significant improvements in immediate memory and attention scores on the RBANS compared to the sham group. However, no significant differences were observed between the two groups in other cognitive domains assessed by the RBANS. No serious adverse events related to rTMS treatment were observed. Conclusion: Treatment with 120% MT rTMS was associated with improvement in cognitive defects related to the active phase of LOD. These findings suggest that rTMS could provide early improvements in cognitive function in clinical settings for elderly patients with LOD.Clinical trial registration: https://www.chictr.org.cn/showproj.html?proj=40698, identifier ChiCTR1900024445.

The brain-derived neurotrophic-factor (BDNF) val66met polymorphism is associated with geriatric depression: a meta-analysis.

Depression has been associated with reduced expression of brain-derived neurotrophic factor (BDNF) in the hippocampus. Genetic association studies of the BDNF Val66Met polymorphism (rs6265) in geriatric depression have produced inconsistent results. A meta-analysis of studies was conducted to compare the frequency of the BDNF Val66Met variant between cases with geriatric depression and age-matched controls. A total of five studies involving 523 cases with geriatric depression and 1,220 psychiatrically healthy controls was included. Met allele carriers had an increased risk for geriatric depression when compared to Val/Val homozygotes (P = 0.004, OR = 1.48, 95% CI = 1.13-1.93). Our findings suggest the BDNF Met allele may confer increased risk for depression as individual age.

The Effect of Perceived Social Support on the Mental Health of Homosexuals: The Mediating Role of Self-Efficacy.

OBJECTIVE: The purpose of this study was to investigate the mental health of homosexual adults in China and to explore the effects of perceived social support and self-efficacy on mental health. METHODS: Two hundred and nine homosexuals were recruited to participate in the online survey. The Perceived Social Support Scale, General Self-efficacy Scale, Self-rating Anxiety Scale and Self-rating Depression Scale were completed through a questionnaire website. Correlation analysis and mediation analysis were used to investigate the relationship between perceived social support, self-efficacy and mental health of homosexuals. RESULTS: Description analysis showed the following: (1) In this study, 53.9% of the participants had depression symptoms and 46.7% had anxiety problems; (2) perceived social support, self-efficacy, anxiety and depression were significantly related to each other. The mediation effect analysis found that self-efficacy mediates between perceived social support and depression but does not mediate between perceived social support and anxiety. CONCLUSIONS: The results demonstrated that in the context of Chinese collectivist culture, homosexuals have certain mental health problems, and their perceived social support and self-efficacy are critical protective factors for mental health. Our findings highlight the need to further strengthen social support and self-efficacy in mental health services for Chinese homosexuals.

Factors of suicidal behavior among inpatients with major depressive disorder: A retrospective case series.

Objective: Previous studies indicate that more than half of those who died by suicide had a depressive disorder. When discussing the factors associated to suicidal behavior (SB) among patients with major depressive disorder (MDD), sociocultural contexts should also be carefully considered. This case series study explored the factors correlated to SB among MDD patients in Beijing, China. Methods: The patient information sheets were retrieved from an electronic database that comprised patient medical information. Three forms of binary logistic regression equations were conducted to explore the factors associated to SB among patients with MDD. For the inconsistent variables produced by the three regression models, the propensity score matching (PSM) analysis was done for further verification. Results: In this retrospective study, 1,091 depressed cases were enrolled. The difference between the SB group and non-SB group in gender, impulsivity, the severity of depression, history of major mental trauma, and family history of suicide were statistically significant in univariate comparisons (P < 0.05); the binary logistic regression analysis and the PSM analysis showed that female gender, history of major mental trauma, impulsivity, family history of suicide and severity of depression were factors correlated to SB among patients with MDD (odds ratios >1). Conclusions: Female gender, the history of major mental trauma, impulsivity, the severity of depression, and family history of suicide were independently associated with the appearance of SB among MDD patients in Beijing, China. Inevitably, these findings should be viewed with particular caution due to the inherent drawbacks of a retrospective nature. More prospective longitudinal research should be conducted to examine those dynamic alterations in the corresponding confounders.

Mobile robot path planning with reformative bat algorithm.

Mobile robot path planning has attracted much attention as a key technology in robotics research. In this paper, a reformative bat algorithm (RBA) for mobile robot path planning is proposed, which is employed as the control mechanism of robots. The Doppler effect is applied to frequency update to ameliorate RBA. When the robot is in motion, the Doppler effect can be adaptively compensated to prevent the robot from prematurely converging. In the velocity update and position update, chaotic map and dynamic disturbance coefficient are introduced respectively to enrich the population diversity and weaken the limitation of local optimum. Furthermore, Q-learning is incorporated into RBA to reasonably choose the loudness attenuation coefficient and the pulse emission enhancement coefficient to reconcile the trade-off between exploration and exploitation, while improving the local search capability of RBA. The simulation experiments are carried out in two different environments, where the success rate of RBA is 93.33% and 90%, respectively. Moreover, in terms of the results of success rate, path length and number of iterations, RBA has better robustness and can plan the optimal path in a relatively short time compared with other algorithms in this field, thus illustrating its validity and reliability. Eventually, by the aid of the Robot Operating System (ROS), the experimental results of real-world robot navigation indicate that RBA has satisfactory real-time performance and path planning effect, which can be considered as a crucial choice for dealing with path planning problems.

Altered Intrinsic Brain Activity in Patients With Late-Life Depression: A Resting-State Functional MRI Study.

Objectives: To investigate the altered intrinsic brain activity (IBA) in patients suffering from late-life depression (LLD) using a percent amplitude of fluctuation (PerAF) method. Methods: In total, fifty patients with LLD and 40 non-depressed controls (NCs) were recruited for the present research. Participants underwent the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) test and resting-state functional MRI (rs-fMRI) scans. The RBANS test consists of 12 sub-tests that contribute to a total score and index scores across the following five domains: immediate memory, visuospatial/constructional, language, attention, and delayed memory. The PerAF method was used for data analysis to detect changes in neural activity in the relevant brain regions. A receiver operating characteristic (ROC) curve was conducted to evaluate the ability of the RBANS test and proposed the PerAF method in distinguishing the two groups. The relationships between altered IBA and neuropsychologic deficits were determined by the Pearson correlation analysis. Results: A significant difference existed in RBANS total score, immediate memory, visuospatial/constructional, language, attention, and delayed memory between groups (P < 0.05). Compared with the NCs group, the LLD group demonstrated decreased PerAF differences in the bilateral superior frontal gyrus, orbital part (Frontal_Sup_Orb), and bilateral anterior cingulate cortex (ACC). The PerAF method and RBANS test exhibited an excellent discriminatory power with the area under curve (AUC) values in distinguishing the two groups. In addition, the attention score of the RBANS test positively correlated with the PerAF values of the bilateral Frontal_Sup_Orb and bilateral ACC. Conclusion: The changes of PerAF in the bilateral Frontal_Sup_Orb and bilateral ACC are related to an increased risk of developing LLD. Moreover, the PerAF method could be used as an underlying sensitivity biomarker to identify the psychiatric disorder.

Prediction of Antidepressant Efficacy by Cognitive Function in First-Episode Late-Life Depression: A Pilot Study.

The response rate of treatment for late-life depression (LLD) is only 25-60%. The cognitive impairment associated with LLD often affects the effectiveness of antidepressants and may has the potential ability to predict response. This study seeks a biomarker for baseline cognitive function to predict efficacy of antidepressants. Sixty patients diagnosed with LLD received escitalopram or sertraline treatment for 8 weeks. Clinical symptom was measured using Hamilton Depression Rating Scale-17 (HAMD-17) and cognitive function was measured using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), Trail Making Test (TMT) before and after 8-week treatment. Patients were divided into treatment effective group (TE) and treatment ineffective group (TI) according to reduction rate in scores of HAMD-17 after treatment. Thirty-eight matched healthy controls (HC) were assessed using RBANS and TMT. There was significant decrease of score of RBANS and increase of score of TMT in patients with LLD compared with HC. Regression analysis revealed that change in HAMD-17 score was significantly positively associated with baseline score of picture naming, figure copy, digit span, and delayed memory. The preliminary findings suggested that working memory, attention, visuospatial, language function, and delayed memory should be examined further as a means of providing the useful objective biomarkers of treatment response. Clinical Trials Registration: [www.ClinicalTrials.gov], identifier [ChiCTR2100042370].