Rectified Latent Variable Model-Based EMG Factorization of Inhibitory Muscle Synergy Components Related to Aging, Expertise and Force-Tempo Variations.

Muscle synergy has been widely acknowledged as a possible strategy of neuromotor control, but current research has ignored the potential inhibitory components in muscle synergies. Our study aims to identify and characterize the inhibitory components within motor modules derived from electromyography (EMG), investigate the impact of aging and motor expertise on these components, and better understand the nervous system's adaptions to varying task demands. We utilized a rectified latent variable model (RLVM) to factorize motor modules with inhibitory components from EMG signals recorded from ten expert pianists when they played scales and pieces at different tempo-force combinations. We found that older participants showed a higher proportion of inhibitory components compared with the younger group. Senior experts had a higher proportion of inhibitory components on the left hand, and most inhibitory components became less negative with increased tempo or decreased force. Our results demonstrated that the inhibitory components in muscle synergies could be shaped by aging and expertise, and also took part in motor control for adapting to different conditions in complex tasks.

Inhibitory Components in Muscle Synergies Factorized by The Rectified Latent Variable Model from Electromyographic Data.

Non-negative matrix factorization (NMF), widely used in motor neuroscience for identifying muscle synergies from electromyographical signals (EMGs), extracts non-negative synergies and is yet unable to identify potential negative components (NegCps) in synergies underpinned by inhibitory spinal interneurons. To overcome this constraint, we propose to utilize rectified latent variable model (RLVM) to extract muscle synergies. RLVM uses an autoencoder neural network, and the weight matrix of its neural network could be negative, while latent variables must remain non-negative. If inputs to the model are EMGs, the weight matrix and latent variables represent muscle synergies and their temporal activation coefficients, respectively. We compared performances of NMF and RLVM in identifying muscle synergies in simulated and experimental datasets. Our simulated results showed that RLVM performed better in identifying muscle-synergy subspace and NMF had a good correlation with ground truth. Finally, we applied RLVM to a previously published experimental dataset comprising EMGs from upper-limb muscles and spike recordings of spinal premotor interneurons (PreM-INs) collected from two macaque monkeys during grasping tasks. RLVM and NMF synergies were highly similar, but a few small negative muscle components were observed in RLVM synergies. The muscles with NegCps identified by RLVM exhibited near-zero values in their corresponding synergies identified by NMF. Importantly, NegCps of RLVM synergies showed correspondence with the muscle connectivity of PreM-INs with inhibitory muscle fields, as identified by spike-triggered averaging of EMGs. Our results demonstrate the feasibility of RLVM in extracting potential inhibitory muscle-synergy components from EMGs.

Moment-to-moment affective dynamics in schizophrenia and bipolar disorder.

BACKGROUND: Affective disturbances in schizophrenia and bipolar disorder may represent a transdiagnostic etiological process as well as a target of intervention. Hypotheses on similarities and differences in various parameters of affective dynamics (intensity, successive/acute changes, variability, and reactivity to stress) between the two disorders were tested. METHODS: Experience sampling method was used to assess dynamics of positive and negative affect, 10 times a day over 6 consecutive days. Patients with schizophrenia (n = 46) and patients with bipolar disorder (n = 46) were compared against age-matched healthy controls (n = 46). RESULTS: Compared to controls, the schizophrenia group had significantly more intense momentary negative affect, a lower likelihood of acute changes in positive affect, and reduced within-person variability of positive affect. The bipolar disorder group was not significantly different from either the schizophrenia group or the healthy control group on any affect indexes. Within the schizophrenia group, level of depression was associated with weaker reactivity to stress for negative affect. Within the bipolar disorder group, level of depression was associated with lower positive affect. CONCLUSIONS: Patients with schizophrenia endured a more stable and negative affective state than healthy individuals, and were less likely to be uplifted in response to happenings in daily life. There is little evidence that these affective constructs characterize the psychopathology of bipolar disorder; such investigation may have been limited by the heterogeneity within group. Our findings supported the clinical importance of assessing multiple facets of affective dynamics beyond the mean levels of intensity.

Dimensional structure of one-year post-COVID-19 neuropsychiatric and somatic sequelae and association with role impairment.

This study examined the latent structure of the broad range of complex neuropsychiatric morbidities occurring 1 year after COVID-19 infection. As part of the CU-COVID19 study, 248 (response rate=39.3%) of 631 adults hospitalized for COVID-19 infection in Hong Kong completed an online survey between March-2021 and January-2022. Disorder prevalence was compared against a random non-infected household sample (n=1834). 248 surveys were received on average 321 days post-infection (Mean age: 48.9, 54% female, moderate/severe/critical infection: 58.2%). 32.4% were screened to have at least one mental disorder, 78.7% of whom had concurrent fatigue/subjective cognitive impairment (SCI). Only PTSD (19.1%) was significantly more common than control (14%, p=0.047). Latent profile analysis classified individuals into P1 (12·4%)-no current neuropsychiatric morbidities, P2 (23.1%)-SCI/fatigue, P3 (45.2%)-anxiety/PTSD, P4 (19.3%)-depression. SCI and fatigue pervaded in all profiles (P2-4) with neuropsychiatric morbidities one-year post-infection. PTSD, anxiety and depressive symptoms were most important in differentiating P2-4. Past mental health and P4 independently predicted functional impairment. Neuropsychiatric morbidity was associated with past mental health, reduced resilience, financial problems, but not COVID-19 severity. Their confluence with depressive and anxiety symptoms predicted impairment and are associated with psychological and environmental factors.

Cost-effectiveness of internet-supported cognitive behavioral therapy for university students with anxiety symptoms: A Markov-model analysis.

BACKGROUND AND AIM: High prevalence of anxiety symptoms has been reported globally in the university students. Cognitive behavioral therapy (CBT) is the recognized treatment for anxiety and is traditionally conducted face-to-face (f-CBT). The efficacy of internet-based CBT (i-CBT) for anxiety has been extensively studied, yet evidence on its cost-effectiveness is scarce. We aimed to evaluate the cost-effectiveness of guided low-intensity i-CBT for university students with mild anxiety symptoms from the societal perspective of Hong Kong. METHODS: A 5-year Markov model was designed to compare outcomes of guided i-CBT and f-CBT in a hypothetical cohort of university students with mild anxiety symptoms. Model inputs of cost and healthcare resources associated with anxiety were retrospectively collected from a cohort of university students with anxiety symptoms. Clinical and utility model inputs were retrieved from published literature. Model outcome measures were anxiety-related total cost (including direct medical and indirect costs) and quality-adjusted life-year (QALY). Sensitivity analyses were performed to examine the robustness of base-case results. RESULTS: In base-case analysis, i-CBT gained higher QALYs (2.9956 versus 2.9917) at lower total cost (US$6,101 versus US$6,246) than f-CBT. In one-way sensitivity analysis, the QALY gained by i-CBT was sensitive to the relative patient acceptance and adherence to CBT. In probabilistic sensitivity analysis, i-CBT was cost-effective in 90.9% of the time at the willingness-to-pay threshold of 138,210 per QALY (3× GDP per capita in Hong Kong). The probability of i-CBT to be cost-effective was 99.9% at a willingness-to-pay threshold of zero. CONCLUSIONS: Guided i-CBT appears to be cost-saving and effective for management of university students with mild symptoms of anxiety from the societal perspective of Hong Kong. The cost-effectiveness of i-CBT is highly subject to the individual acceptance and adherence of CBT delivered by the internet platform.

Protocol for a prospective open-label clinical trial to investigate the utility of concurrent TBS/fNIRS for antidepressant treatment optimisation.

INTRODUCTION: Repetitive transcranial magnetic stimulation (rTMS) with theta burst stimulation (i.e. TBS) of the dorsolateral prefrontal cortex (DLPFC) is an innovative treatment for major depressive disorder (MDD). However, fewer than 50% of patients show sufficient response to this treatment; markers for response prediction are urgently needed. Research shows considerable individual variability in the brain responses to rTMS. However, whether differences in individual DLPFC modulation by rTMS can be used as a predictive marker for treatment response remains to be investigated. Here, we present a research programme that will exploit the combination of functional near-infrared spectroscopy (fNIRS) with brain stimulation. Concurrent TBS/fNIRS will allow us to systematically investigate TBS-induced modulation of blood oxygenation as a proxy for induced brain activity changes. The findings from this study will (1) elucidate the immediate effects of excitatory and inhibitory TBS on prefrontal activity in TBS treatment-naïve patients with MDD and (2) validate the potential utility of TBS-induced brain modulation at baseline for the prediction of antidepressant response to 4 weeks of daily TBS treatment. METHODS AND ANALYSIS: Open-label, parallel-group experiment consisting of two parts. In part 1, 70 patients and 37 healthy controls will be subjected to concurrent TBS/fNIRS. Intermittent TBS (iTBS) and continuous TBS (cTBS) will be applied on the left and right DLPFC, respectively. fNIRS data will be acquired before, during and several minutes after stimulation. In part 2, patients who participated in part 1 will receive a 4 week iTBS treatment of the left DLPFC, performed daily for 5 days per week. Psychometric evaluation will be performed periodically and at 1 month treatment follow-up. Statistical analysis will include a conventional, as well as a machine learning approach. ETHICS AND DISSEMINATION: Ethics approval was obtained from the Institutional Review Board. Findings will be disseminated through scientific journals, conferences and university courses. TRIAL REGISTRATION NUMBER: NCT04526002.

ADHD Comorbidity Structure and Impairment: Results of the WHO World Mental Health Surveys International College Student Project (WMH-ICS).

OBJECTIVE: To examine the prevalence of ADHD and the association of comorbid disorders, and multivariate disorder classes with role impairment in college students. METHOD: About 15,991 freshmen (24 colleges, 9 countries, WMH-ICS) (response rate = 45.6%) completed online WMH-CIDI-SC surveys for 6-month ADHD and six 12-month DSM-IV disorders. We examined multivariate disorder classes using latent class analysis (LCA) and simulated a population attributable risk proportions (PARPs) of ADHD-related impairment. RESULTS: About 15.9% had ADHD, of which 58.4% had comorbidities. LCA classified ADHD respondents to pure (42.9%), internalizing (36.0%), bipolar comorbidities (11.3%), and externalizing disorder classes (9.8%). ADHD, comorbidities, and multivariate disorder classes independently predicted severe impairment. PARPs: eliminating ADHD hypothetically reduced severe impairment by 19.2%, 10.1% adjusted for comorbidities, 9.5% for multivariate disorder classes. CONCLUSIONS: ADHD and comorbid disorders are common and impairing in college students. Personalized transdiagnostic interventions guided by multivariate disorder classes should be explored.

The Differential Effects of Social Media on Depressive Symptoms and Suicidal Ideation Among the Younger and Older Adult Population in Hong Kong During the COVID-19 Pandemic: Population-Based Cross-sectional Survey Study.

BACKGROUND: Social media has become a ubiquitous part of daily life during the COVID-19 pandemic isolation. However, the role of social media use in depression and suicidal ideation of the general public remains unclear. Related empirical studies were limited and reported inconsistent findings. Little is known about the potential underlying mechanisms that may illustrate the relationship between social media use and depression and suicidal ideation during the COVID-19 pandemic. OBJECTIVE: This study tested the mediation effects of social loneliness and posttraumatic stress disorder (PTSD) symptoms on the relationship between social media use and depressive symptoms and suicidal ideation, as well as the moderation effect of age on the mediation models. METHODS: We administered a population-based random telephone survey in May and June 2020, when infection control measures were being vigorously implemented in Hong Kong. A total of 1070 adults (658 social media users and 412 nonusers) completed the survey. Structural equation modeling (SEM) and multigroup SEM were conducted to test the mediation and moderation effects. RESULTS: The weighted prevalence of probable depression was 11.6%; 1.6% had suicidal ideation in the past 2 weeks. Both moderated mediation models of depressive symptoms (χ262=335.3; P<.05; comparative fit index [CFI]=0.94; nonnormed fit index [NNFI]=0.92; root mean square error of approximation [RMSEA]=0.06) and suicidal ideation (χ234=50.8; P<.05; CFI=0.99; NNFI=0.99; RMSEA=0.02) showed acceptable model fit. There was a significantly negative direct effect of social media use on depressive symptoms among older people (ß=-.07; P=.04) but not among younger people (ß=.04; P=.55). The indirect effect via PTSD symptoms was significantly positive among both younger people (ß=.09; P=.02) and older people (ß=.10; P=.01). The indirect effect via social loneliness was significant among older people (ß=-.01; P=.04) but not among younger people (ß=.01; P=.31). The direct effect of social media use on suicidal ideation was not statistically significant in either age group (P>.05). The indirect effects via PTSD symptoms were statistically significant among younger people (ß=.02; P=.04) and older people (ß=.03; P=.01). Social loneliness was not a significant mediator between social media use and suicidal ideation among either age group (P>.05). CONCLUSIONS: Social media may be a "double-edged sword" for psychosocial well-being during the COVID-19 pandemic, and its roles vary across age groups. The mediators identified in this study can be addressed by psychological interventions to prevent severe mental health problems during and after the COVID-19 pandemic.

Antidepressant efficacy of low-frequency repetitive transcranial magnetic stimulation in antidepressant-nonresponding bipolar depression: a single-blind randomized sham-controlled trial.

BACKGROUND: To examine the antidepressant efficacy and response predictors of R-DLPFC-LF rTMS for antidepressant-nonresponding BD. METHODS: We conducted a single-blind randomized sham-controlled trial for 54 (28 sham, 26 active) patients with antidepressant-nonresponding BD (baseline MADRS ≥ 20). Patients received 15 daily sessions of active or sham neuronavigated rTMS (Figure-of-8 coil, five 1 Hz 60 s 110% RMT trains). Outcome measures included depressive response (≥ 50% MADRS reduction, CGI ≤ 2) and remission (MADRS < 7, CGI = 1) rates, treatment emergent hypo/mania (YMRS), depressive and anxiety symptoms (HAM-A). RESULTS: 48 patients (25 sham, 23 active) completed treatment, with 3 drop-outs each in active and sham groups. Active rTMS did not produce superior response or remission rates at endpoint or 6 or 12 weeks (ps > 0.05). There was no significant group * time interaction (ps > 0.05) in a multivariate ANOVA with MADRS, HAMA and YMRS as dependent variables. Exploratory analysis found MADRS improvement to be moderated by baseline anxiety (p = 0.02) and melancholia (p = 0.03) at week 3, and depressive onset at weeks 6 (p = 0.03) and 12 (p = 0.04). In subjects with below-mean anxiety (HAMA < 20.7, n = 24), MADRS improvement from active rTMS was superior to sham at week 3 (ITT, t = 2.49, p = 0.04, Cohen's d = 1.05). No seizures were observed. Groups did not differ in treatment-emergent hypomania (p = 0.1). LIMITATIONS: Larger sample size might be needed to power subgroup analyses. Moderation analyses were exploratory. Single-blind design. Unblinding before follow-up assessments due to ethical reasons. CONCLUSIONS: 1-Hz 110% RMT (5 × 60 s trains) R-DLPFC-LF rTMS was not effective for antidepressant non-responding BD but may be further investigated at increased dosage and/or in BD patients with low anxiety. Trial registration CCRB Clinical Trials Registry, CUHK, CUHK_CCT00440. Registered 04 December 2014, https://www2.ccrb.cuhk.edu.hk/registry/public/279.

Diagnostic Outcomes of Childhood ADHD in Chinese Adults.

Objective: We examined adulthood diagnostic, functioning, and social outcomes of childhood ADHD in a Hong Kong Chinese clinical sample. Method: We identified from the central registry 499 Chinese adults clinically diagnosed with ADHD aged 6 to 12 in 2002-2005 in four Hong Kong child psychiatric centers. Assessments included ADHD Clinical Diagnostic Scale (ACDS), Structured Clinical Interview for DSM Disorders (SCID), and World Health Organization Disability Assessment Schedule (WHO-DAS). Results: Eligible participants = 499. One hundred forty-five completed assessments, two deceased, six incarcerated, 100 had invalid contact, 83 declined, 34 emigrated, and 129 unable to attend. Mean follow-up duration = 14.9 years. Nonrespondents were slightly younger (19.78 vs. 20.53, p < .001). In all, 83.1% of all participants currently met Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5) ADHD criteria (36.8% inattentive subtype (IA), 43% combined, 3.3% hyperactive/impulsive subtype (H/I) ). One third of persistent ADHD participants currently received care. ADHD persistence was associated with significantly increased psychiatric comorbidity (49.5% vs. 22.7%, p = .02) and poor academic and social outcomes. ADHD persistence and comorbidity independently predicted impairment. Conclusion: Adulthood-persistence of clinically presented childhood ADHD is common and impairing in Hong Kong Chinese.

Unaltered Brain GABA Concentrations and Resting fMRI Activity in Functional Dyspepsia With and Without Comorbid Depression.

BACKGROUND: GABA-deficit characterizes depression (MDD), which is highly comorbid with Functional Dyspepsia (FD). We examined brain GABA concentrations and resting activities in post-prandial distress subtype FD (FD-PDS) patients with and without MDD. METHODS: 24 female age/education-matched FD-PDS with comorbid MDD (FD-PDS-MDD), non-depressed FD-PDS, and healthy controls each were compared on GABA concentrations, resting fMRI (fALFF) in bilateral pregenual anterior cingulate (pgACC), left dorsolateral prefrontal cortex (DLPFC), insula, and somatosensory cortex (SSC). RESULTS: FD-PDS-MDD patients had mild though elevated depressive symptoms. FD-PDS patients had generally mild dyspeptic symptoms. No significant between-group differences in GABA or fALFF were found. No significant correlations were found between GABA and depressive/dyspeptic symptoms after Bonferroni correction. In patients, GABA correlated positively with left insula fALFF (r = 0.38, Bonferroni-corrected p = .03). CONCLUSION: We did not find altered GABA concentrations or brain resting activity in FD-PDS or its MDD comorbidity. The neurochemical link between MDD and FD remains elusive.

Prevalence and correlates of bipolar II disorder in major depressive patients at a psychiatric outpatient clinic in Hong Kong.

BACKGROUND: Western studies indicate a high prevalence of bipolar II disorder defined by a Research Diagnostic Criteria 2-day hypomania duration criterion (30 to 61%) amongst clinically depressive patients. The situation in Chinese patients with depression is unknown. METHODS: 64 (52.5% response rate) patients first presenting to a Hong Kong public psychiatric outpatient clinic in 2005 with a diagnosis of major depression were recruited. The SCID and Family History Screen were administered. RESULTS: DSM-IV bipolar II was found in 20.5% of depressive outpatients; 35.9% had bipolar II disorder defined by RDC 2-day duration criterion for hypomania. Family bipolarity, age of onset, and depressive recurrence distinguished bipolar II subjects from unipolar depressives irrespective of duration criteria chosen for hypomania. LIMITATIONS: Sample size was limited. CONCLUSIONS: Bipolar II disorder is common amongst Chinese depressive outpatients. The evaluation method and 2-day duration criterion for hypomania were supported by bipolar validators. Replication using larger samples is needed to arrive at a more representative prevalence estimate and to enable more refined nosological evaluation.

Acupuncture and related therapies for treating irritable bowel syndrome: overview of systematic reviews and network meta-analysis.

BACKGROUND: An overview of systematic reviews (SRs) and a network meta-analysis (NMA) were conducted to evaluate the comparative effectiveness of acupuncture and related therapies used either alone, or as an add-on to other irritable bowel syndrome (IBS) treatments. METHODS: A total of eight international and Chinese databases were searched for SRs of randomized controlled trials (RCTs). The methodological quality of SRs was appraised using the AMSTAR instrument. From the included SRs, data from RCTs were extracted for the random-effect pairwise meta-analyses. An NMA was used to evaluate the comparative effectiveness of different treatment options. The risk of bias among included RCTs was assessed using the Cochrane risk of bias tool. RESULTS: From 15 SRs of mediocre quality, 27 eligible RCTs (n = 2141) were included but none performed proper blinding. Results from pairwise meta-analysis showed that both needle acupuncture and electroacupuncture were superior in improving global IBS symptoms when compared with pinaverium bromide. NMA results showed needle acupuncture plus Geshanxiaoyao formula had the highest probability of being the best option for improving global IBS symptoms among 14 included treatment options, but a slight inconsistency exists. CONCLUSION: The risk of bias and NMA inconsistency among included trials limited the trustworthiness of the conclusion. Patients who did not respond well to first-line conventional therapies or antidepressants may consider acupuncture as an alternative. Future trials should investigate the potential of (1) acupuncture as an add-on to antidepressants and (2) the combined effect of Chinese herbs and acupuncture, which is the norm of routine Chinese medicine practice.

Cognitive Impairment In Treatment-Naïve Bipolar II and Unipolar Depression.

Cognition dysfunction may reflect trait characteristics of bipolarity but cognitive effects of medications have confounded previous comparisons of cognitive function between bipolar II and unipolar depression, which are distinct clinical disorders with some overlaps. Therefore, we examined the executive function (WCST), attention, cognitive speed (TMT-A) and memory (CAVLT, WMS-Visual reproduction) of 20 treatment-naïve bipolar II patients (BPII), 35 treatment-naïve unipolar depressed (UD) patients, and 35 age/sex/education matched healthy controls. The subjects were young (aged 18-35), and had no history of psychosis or substance use, currently depressed and meeting either RDC criteria for Bipolar II Disorder or DSM-IV-TR criteria for Major Depressive Disorder. The patients were moderately depressed (MADRS) and anxious(HAM-A), on average within 3.44 years of illness onset. Sociodemographic data and IQ were similar between the groups. UD patients had significantly slower cognitive speed and cognitive flexibility (WCST perseverative error). BPII depressed patients showed relatively intact cognitive function. Verbal memory (CAVLT List A total) correlated with illness chronicity only in BPII depression, but not UD. In conclusion, young and treatment-naïve BPII depressed patients differed from unipolar depression by a relatively intact cognitive profile and a chronicity-cognitive correlation that suggested a stronger resemblance to Bipolar I Disorder than Unipolar Depression.

Increased Glutamate in Somatosensory Cortex in Functional Dyspepsia.

Functional Dyspepsia-Post-prandial Distress Syndrome (FD-PDS) was associated with mood-related increases in resting activity and lowered activation threshold in the somatosensory cortex (SSC), insula and perigenual anterior cingulate cortex(pgACC) in functional imaging studies. The underlying cortical neurochemical changes are unknown. We performed proton Magnetic Resonance Spectroscopy (1H-MRS) on 17 consecutive tertiary clinic-recruited psychotropic-naïve Rome III FD-PDS female and 17 age-sex matched healthy controls. Voxels were placed on bilateral pgACC, left insula and SSC. Water-suppressed spectra were acquired using PRESS with short echo time (TE) (T = 24 ms) to separately quantify glutamate (Glu) and glutamine (Gln). Main outcome measure was regional Glu/Cr + PCr. Severity of depression, anxiety, somatization, and dyspepsia were also assessed. We found significantly increased SSC Glu/Cr + PCr in FD-PDS subjects compared to controls. SSC Glu/Cr + PCr correlated significantly with postprandial distress chronicity, dyspeptic symptoms severity and anxiety. The SSC Glu/Cr + PCr - dyspepsia correlations became insignificant after controlling for anxiety but were independent of depression. Gln/Glu ratio, which indicates glial Glu cycling failure, was unchanged. No between-group differences were noted in other regional metabolite concentrations. Our findings suggested enhanced SSC glutamate transmission in FD-PDS that was linked to post-prandial distress chronicity and severity and anxiety.

The Bipolar II Depression Questionnaire: A Self-Report Tool for Detecting Bipolar II Depression.

Bipolar II (BP-II) depression is often misdiagnosed as unipolar (UP) depression, resulting in suboptimal treatment. Tools for differentiating between these two types of depression are lacking. This study aimed to develop a simple, self-report screening instrument to help distinguish BP-II depression from UP depressive disorder. A prototype BP-II depression questionnaire (BPIIDQ-P) was constructed following a literature review, panel discussions and a field trial. Consecutively assessed patients with a diagnosis of depressive disorder or BP with depressive episodes completed the BPIIDQ-P at a psychiatric outpatient clinic in Hong Kong between October and December 2013. Data were analyzed using discriminant analysis and logistic regression. Of the 298 subjects recruited, 65 (21.8%) were males and 233 (78.2%) females. There were 112 (37.6%) subjects with BP depression [BP-I = 42 (14.1%), BP-II = 70 (23.5%)] and 182 (62.4%) with UP depression. Based on family history, age at onset, postpartum depression, episodic course, attacks of anxiety, hypersomnia, social phobia and agoraphobia, the 8-item BPIIDQ-8 was constructed. The BPIIDQ-8 differentiated subjects with BP-II from those with UP depression with a sensitivity/specificity of 0.75/0.63 for the whole sample and 0.77/0.72 for a female subgroup with a history of childbirth. The BPIIDQ-8 can differentiate BP-II from UP depression at the secondary care level with satisfactory to good reliability and validity. It has good potential as a screening tool for BP-II depression in primary care settings. Recall bias, the relatively small sample size, and the high proportion of females in the BP-II sample limit the generalization of the results.

Would transcranial direct current stimulation (tDCS) enhance the effects of working memory training in older adults with mild neurocognitive disorder due to Alzheimer's disease: study protocol for a randomized controlled trial.

BACKGROUND: There has been longstanding interesting in cognitive training for older adults with cognitive impairment. In this study, we will investigate the effects of working memory training, and explore augmentation strategies that could possibly consolidate the effects in older adults with mild neurocognitive disorder. Transcranial direct current stimulation (tDCS) has been demonstrated to affect the neuronal excitability and reported to enhance memory performance. As tDCS may also modulate cognitive function through changes in neuroplastic response, it would be adopted as an augmentation strategy for working memory training in the present study. METHODS/DESIGN: This is a 4-week intervention double-blind randomized controlled trial (RCT) of tDCS. Chinese older adults (aged 60 to 90 years) with mild neurocognitive disorder due to Alzheimer's disease (DSM-5 criteria) would be randomized into a 4-week intervention of either tDCS-working memory (DCS-WM), tDCS-control cognitive training (DCS-CC), and sham tDCS-working memory (WM-CD) groups. The primary outcome would be working memory test - the n-back task performance and the Chinese version of the Alzheimer's Disease Assessment Scale - Cognitive Subscale (ADAS-Cog). Secondary outcomes would be test performance of specific cognitive domains and mood. Intention-to-treat analysis would be carried out. Changes of efficacy indicators with time and intervention would be tested with mixed effect models. DISCUSSION: This study adopts the theory of neuroplasticity to evaluate the potential cognitive benefits of non-invasive electrical brain stimulation, working memory training and dual stimulation in older adults at risk of cognitive decline. It would also examine the tolerability, program adherence and adverse effects of this novel intervention. Information would be helpful for further research of dementia prevention studies. TRIAL REGISTRATION: ChiCTR-TRC- 14005036 Date of registration: 31 July 2014.

Psychometric properties of the Hong Kong Chinese (Cantonese) TEMPS-A in medical students.

BACKGROUND: The self-rated auto-questionnaire, the Temperament Scale of Memphis, Pisa, Paris and San Diego (TEMPS-A) is the latest development in the study of temperamental attributes. It has been used and validated in different cultures and countries. The current study aims at validating the Chinese (Cantonese) version of the TEMPS-A and comparing the psychometric properties of the long and short forms of the translated scale. METHODS: The Chinese (Cantonese) version of TEMPS-A was prepared with the standard translation and back-translation method, and approved by the original authors (HSA & KKA). It was administered to medical students of the two local universities, and results were analyzed. RESULTS: 613 valid questionnaires were returned. The Cronbach-Alpha coefficients for the depressive, cyclothymic, hyperthymic, irritable and anxious temperament subscales were 0.63, 0.82, 0.78, 0.80, and 0.84, respectively. The strongest correlation was observed between the cyclothymic and irritable temperaments (R=0.600). Factor analysis yielded one large composite (depressive and anxious) and four homogenous factors, cyclothymic, anxious, hyperthymic and irritable. A newly reconstituted 43-item short form, based on methods suggested by the original authors yielded similar factor structure. LIMITATIONS: The narrow age range of subjects somewhat limits generalization of the results. However, external and concurrent validations against other validated scales have been demonstrated for the original English versions as well as against the most commonly used languages of the world; furthermore, such validation has also been demonstrated for Chinese (Mandarin). CONCLUSIONS: The Chinese (Cantonese) version of TEMPS-A and the reconstituted 43-item short form were found to have good internal consistency and factor structures comparable to those of other languages from diverse cultures across the planet. We propose that the Cantonese TEMPS-A is a useful tool for local use.

Validation of the Developmental, Dimensional and Diagnostic Interview (3Di) Among Chinese Children in a Child Psychiatry Clinic in Hong Kong.

Autism spectrum disorder (ASD) is a disorder with high levels of co-morbidities. The Developmental, Dimensional and Diagnostic Interview (3 Di) is a relatively new instrument designed to provide dimensional as well as categorical assessment of autistic behaviours among children with normal intelligence. Its sound psychometric properties and relatively short administration time make it a versatile instrument. The 3 Di was translated into Chinese (Cantonese) and its applicability among 194 clinic children was examined. Results found excellent reliability and validity, and achieved a sensitivity of 95% and specificity of 77%. It was able to capture the diagnosis of ASD among children presenting with attention deficit hyperactivity disorder. However, although the disorder of ASD is considered universal, the use of a western instrument in a Chinese context should also take note of cultural influences that may impact on the manifestation of its symptoms.

Neurocognitive profiles of people with borderline personality disorder.

PURPOSE OF REVIEW: This review summarizes recent neurocognitive research to better delineate the nosology, prognostication and cause underlying borderline personality disorder (BPD). RECENT FINDINGS: BPD had marked clinical heterogeneity with high comorbidity. Executive dysfunction in this disorder was linked to suicidality and treatment adherence, and may serve as an endophenotype. BPD was also characterized by cognitive distortions such as risky decision-making, deficient feedback processing, dichotomous thinking, jumping to conclusion, monocausal attribution and paranoid cognitive style. Social cognition deficits recently described in BPD include altered social inference and emotional empathy, hypermentalization, poorer facial emotional recognition and facial expressions. In electrophysiological studies, BPD was found to have predominantly right hemispheric deficit in high-order cortical inhibition. Reduced left orbitofrontal activity by visual evoked potential and magnetoencephalography correlated with depressive symptoms and functional deterioration. Brain structures implicated in BPD include the hippocampus, dorsolateral prefrontal cortex and anterior cingulate cortex. Abnormal anatomy and functioning of frontolimbic circuitry appear to correlate with cognitive deficits. SUMMARY: Frontolimbic structural and functional abnormalities underlie the broad array of cognitive abnormalities in BPD. Further research should espouse broader considerations of effects of comorbidity and clinical heterogeneity, and include community samples and, possibly, longitudinal designs.