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In this paper we discuss laboratory experiments that address the problem of self-governance in an asymmetric commons dilemma. Small-scale irrigation systems that provide food for hundreds of millions of people around the world are probably the most common example of such dilemmas. Here, we formulate an abstract dilemma in which subjects make both a decision about investment in the provision of infrastructure associated with the use of a resource and about how much to extract from the common-pool resource made available by this infrastructure. The impact of inherent asymmetry in irrigation systems on the provision of a resource and the impact of communication on the capacity of the group to solve the two-level commons dilemma of cooperation and coordination based on the analysis of the experimental data are discussed.
V5579 Sgr was a fast nova discovered in 2008 April 18.784 UT. We present the optical spectroscopic observations of the nova observed from the Castanet Tolosan, SMARTS, and CTIO observatories spanning over 2008 April 23 to 2015 May 11. The spectra are dominated by hydrogen Balmer, Fe II, and O I lines with P-Cygni profiles in the early phase, typical of an Fe II class nova. The spectra show He I and He II lines along with forbidden lines from N, Ar, S, and O in the nebular phase. The nova showed a pronounced dust formation episode that began about 20 days after the outburst. The dust temperature and mass were estimated using the WISE data from spectral energy distribution (SED) fits. The PAH-like features are also seen in the nova ejecta in the mid-infrared Gemini spectra taken 522 d after the discovery. Analysis of the light curve indicates values of $t_2$ and $t_3$ about 9 and 13 days, respectively, placing the nova in the category of fast nova. The best-fit cloudy model of the early decline phase JHK spectra obtained on 2008 May 3 and the nebular optical spectrum obtained on 2011 June 2 shows a hot white dwarf source with $T_{BB}$$\sim$ 2.6 $\times$ 10$^5$ K having a luminosity of 9.8 $\times$ 10$^{36}$ ergs s$^{-1}$. Our abundance analysis shows that the ejecta is significantly enhanced relative to solar, O/H = 32.2, C/H = 15.5, and N/H = 40.0 in the early decline phase and O/H = 5.8, He/H = 1.5, and N/H = 22.0 in the nebular phase.
Auditory system plasticity is a promising target for neuromodulation, cognitive rehabilitation and therapeutic development in schizophrenia (SZ). Auditory-based targeted cognitive training (TCT) is a ‘bottom up’ intervention designed to enhance the speed and accuracy of auditory information processing, which has been shown to improve neurocognition in certain SZ patients. However, the dynamics of TCT learning as a function of training exercises and their impact on neurocognitive functioning and therapeutic outcomes are unknown.
Methods
Forty subjects (SZ, n = 21; healthy subjects (HS), n = 19) underwent comprehensive clinical, cognitive, and auditory assessments, including measurements of auditory processing speed (APS) at baseline and after 1-h of TCT. SZ patients additionally completed 30-hours of TCT and repeated assessments ~10–12 weeks later.
Results
SZ patients were deficient in APS at baseline (d = 0.96, p < 0.005) relative to HS. After 1-h of TCT, analyses revealed significant main effects of diagnosis (d = 1.75, p = 0.002) and time (d = 1.04, p < 0.001), and a diagnosis × time interaction (d = 0.85, p = 0.02) on APS. APS learning effects were robust after 1-h in SZ patients (d = 1.47, p < 0.001) and persisted throughout the 30-h of training. Baseline APS was associated with verbal learning gains after 30-h of TCT (r = 0.51, p = 0.02) in SZ.
Conclusions
TCT learning metrics may have prognostic utility and aid in the prospective identification of individuals likely to benefit from TCT. Future experimental medicine studies may advance predictive algorithms that enhance TCT-related clinical, cognitive and functional outcomes.
OBJECTIVES/GOALS: The correction of spinopelvic parameters is associated with better outcomes in patients with adult spinal deformity (ASD). This study presents a novel artificial intelligence (AI) tool that automatically predicts spinopelvic parameters from spine x-rays with high accuracy and without need for any manual entry. METHODS/STUDY POPULATION: The AI model was trained/validated on 761 sagittal whole-spine x-rays to predict the following parameters: Sagittal Vertical Axis (SVA), Pelvic Tilt (PT), Pelvic Incidence (PI), Sacral Slope (SS), Lumbar Lordosis (LL), T1-Pelvic Angle (T1PA), and L1-Pelvic Angle (L1PA). A separate test set of 40 x-rays was labeled by 4 reviewers including fellowship-trained spine surgeons and a neuroradiologist. Median errors relative to the most senior reviewer were calculated to determine model accuracy on test and cropped-test (i.e. lumbosacral) images. Intraclass correlation coefficients (ICC) were used to assess inter-rater reliability RESULTS/ANTICIPATED RESULTS: The AI model exhibited the following median (IQR) parameter errors: SVA[2.1mm (8.5mm), p=0.97], PT [1.5° (1.4°), p=0.52], PI[2.3° (2.4°), p=0.27], SS[1.7° (2.2°), p=0.64], LL [2.6° (4.0°), p=0.89], T1PA [1.3° (1.1°), p=0.41], and L1PA [1.3° (1.2°), p=0.51]. The parameter errors on cropped lumbosacral images were: LL[2.9° (2.6°), p=0.80] and SS[1.9° (2.2°), p=0.78]. The AI model exhibited excellent reliability at all parameters in both whole-spine (ICC: 0.92-1.0) and lumbosacral x-rays: (ICC: 0.92-0.93). DISCUSSION/SIGNIFICANCE: Our AI model accurately predicts spinopelvic parameters with excellent reliability comparable to fellowship-trained spine surgeons and neuroradiologists. Utilization of predictive AI tools in spine-imaging can substantially aid in patient selection and surgical planning.
Substance use is a complex condition with multidimensional determinants. The present study aims to find the prevalence and determinants of substance use among young people attending primary healthcare centers in India.
Methods
A multicentric cross-sectional study was conducted across 15 states in India on 1,630 young people (10–24 years) attending primary health centers. The Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST) was used to capture data on substance use. The degree of substance involvement was assessed and multivariate regression analysis was conducted to determine the risk factors of substance use.
Results
The prevalence of substance use was 32.8%, with a median substance initiation age of 18 years. Among the substance users, 75.5% began before completing adolescence. Tobacco (26.4%), alcohol (26.1%) and cannabis (9.5%) were commonly consumed. Sociodemographic determinants included higher age, male gender, urban residence, positive family history, northeastern state residence and lower socioeconomic class. Over 80% of users had moderate or high involvement.
Conclusions
High substance use prevalence among young people in Indian healthcare centers underscores the urgency of targeted intervention. Insights on determinants guide effective prevention strategies for this complex public health issue.
As the population continues to age at a rapid pace, an important question that has been raised by clinicians and researchers alike, is “how can we preserve our cognitive abilities as older adults?” Cognitive reserve (CR) is thought to account for inter-individual differences in the cognitive trajectories of older people experiencing similar levels of brain pathology. Being a hypothetical construct, CR cannot be measured directly and therefore, must be operationalized through a combination of demographic and lifestyle variables. While there is sufficient empirical evidence supporting the relationship between individual CR proxies and cognitive functioning, few studies to date have explored which CR proxy is most important in predicting aspects of late-life cognitive functioning and whether composite measure of CR accurately predict cognitive functioning, above and beyond variables traditionally associated with late-life cognitive ability (e.g., age, gender, cardiovascular risk, depression). The present cross-sectional study sought to examine the relationship between three well-established CR proxies—educational attainment, mental workplace demands, crystallized intelligence—and baseline neuropsychological functioning in a clinical sample of older adults without dementia.
Participants and Methods:
Using archival data from 248 older adult patients seen at geriatric specialist hospital in Ontario, Canada, we examined the cumulative and independent effects of educational attainment (years of formal education), mental workplace demands (mean analyst rating for 10 O*NET variables measuring cognitively complex work activities), and crystallized intelligence (score on WASI-I Vocabulary subtest) on performance across several neuropsychological tests assessing i.) verbal memory, ii.) visual memory, iii.) attention, concentration, and working memory, iv.) executive functioning, v.) visuospatial processing, and vi.) language. Composite scores for all six cognitive domains were calculated by averaging converted z-scores on domain-specific tests of neuropsychological functioning. A series of regression models were then constructed to evaluate the relationship between CR and late-life cognitive functioning. To determine the relative importance of each CR proxy, a follow-up relative weight analysis (RWA) was performed for each regression model.
Results:
After controlling for age, gender, cardiovascular risk, and depression, our composite measure of CR (average z-score of educational attainment, mental workplace demands, crystallized intelligence) proved to be a significant predictor across all domains of cognitive functioning. Of the six cognitive domains assessed, CR was the most important in predicting higher-order cognitive functions, such as working memory and executive functioning. Out of the three CR proxies, crystallized intelligence was the only CR proxy that significantly predicted performance across all six cognitive domains. RWA revealed that crystallized intelligence was the most important in predicting neuropsychological functioning, followed by educational attainment, and mental workplace demands.
Conclusions:
Despite being closely related, all three CR proxies demonstrated differential effects on late-life cognitive functioning. Overall, our findings suggest that the effects of CR are not generalizable across all cognitive domains and appears to be somewhat dependent on the CR proxy used. This study supports the existing literature in demonstrating the robustness of crystallized intelligence as a CR proxy and provides preliminary evidence supporting the idea that tasks that require higher levels of cognitive processing are the most influenced by CR.
Social connections have a significant impact on health across age groups, including older adults. Loneliness and social isolation are known risk factors for Alzheimer’s disease and related dementias (ADRD). Yet, we did not find a review focused on meta-analyses and systematic reviews of studies that had examined associations of social connections with cognitive decline and trials of technology-based and other social interventions to enhance social connections in people with ADRD.
Study design:
We conducted a scoping review of 11 meta-analyses and systematic reviews of social connections as possible determinants of cognitive decline in older adults with or at risk of developing ADRD. We also examined eight systematic reviews of technology-based and other social interventions in persons with ADRD.
Study results:
The strongest evidence for an association of social connections with lower risk of cognitive decline was related to social engagement and social activities. There was also evidence linking social network size to cognitive function or cognitive decline, but it was not consistently significant. A number of, though not all, studies reported a significant association of marital status with risk of ADRD. Surprisingly, evidence showing that social support reduces the risk of ADRD was weak. To varying degrees, technology-based and other social interventions designed to reduce loneliness in people with ADRD improved social connections and activities as well as quality of life but had no significant impact on cognition. We discuss strengths and limitations of the studies included.
Conclusions:
Social engagement and social activities seem to be the most consistent components of social connections for improving cognitive health among individuals with or at risk for ADRD. Socially focused technology-based and other social interventions aid in improving social activities and connections and deserve more research.
Internet use has become integral part of daily living in current world; at the same time its misuse is likely to cause addiction and negative impact in mental health. Internet addiction is similar to other substance addiction and has been associated with different psychiatric comorbidities.
Objectives
To study prevalence of internet use disorder in youth patients,to find the association of psychiatric comorbidities with pattern of internet use and to study socio-demographic variables.
Methods
An institutional based cross-sectionalstudy was carried out in psychiatric out-patientdepartment of tertiary hospital. A total of 146 youth patients (15-24 years) who consented for the study were enrolled. Psychiatric diagnosis was made by the consultant psychiatrist using ICD-10/DSR criteria.
Results
Out of total 146 patients with mean age 19.99 years, internet use was found in 89.7% of youth patients out of which 63.7% used in single device and 26.3% in multiple devices. Internet addiction was found in 67.8% youth patients and internet gaming in 33.6% patients. Higher level of internet addiction was found in adolescent (15-19 years) than adult (20-24 years) with statistically significant p value 0.014; patients from middle and higher socio-economic condition than low socio-economic conditionwith statistically significant p value 0.024; patients from uran region compared to semi-urban and rural with statistically significant p value 0.000; and patient using internet gaming with statistically significant p vallue 0.000. Among psychiatric diagnosis, ANxiety, depression and subtance use disorders were associated with internet use disorder however were statistically insignificant.
Conclusions
Internet addiction is high in youth patients; adolescent (15-19 years) compared to adults (20-24 years). Anxiety, Depression and substance use disorders had higher association with internet use disorder.
The current small study utilised prospective data collection of patterns of prenatal alcohol and tobacco exposure (PAE and PTE) to examine associations with structural brain outcomes in 6-year-olds and served as a pilot to determine the value of prospective data describing community-level patterns of PAE and PTE in a non-clinical sample of children. Participants from the Safe Passage Study in pregnancy were approached when their child was ∼6 years old and completed structural brain magnetic resonance imaging to examine with archived PAE and PTE data (n = 51 children–mother dyads). Linear regression was used to conduct whole-brain structural analyses, with false-discovery rate (FDR) correction, to examine: (a) main effects of PAE, PTE and their interaction; and (b) predictive potential of data that reflect patterns of PAE and PTE (e.g. quantity, frequency and timing (QFT)). Associations between PAE, PTE and their interaction with brain structural measures demonstrated unique profiles of cortical and subcortical alterations that were distinct between PAE only, PTE only and their interactive effects. Analyses examining associations between patterns of PAE and PTE (e.g. QFT) were able to significantly detect brain alterations (that survived FDR correction) in this small non-clinical sample of children. These findings support the hypothesis that considering QFT and co-exposures is important for identifying brain alterations following PAE and/or PTE in a small group of young children. Current results demonstrate that teratogenic outcomes on brain structure differ as a function PAE, PTE or their co-exposures, as well as the pattern (QFT) or exposure.
Patients with major depressive disorder (MDD) with acute suicidal ideation or behavior (MDSI) require immediate intervention. Though oral antidepressants can be effective at reducing depressive symptoms, they can take 4–6 weeks to reach full effect.
Objectives
This study aimed to identify unmet needs in the treatment of patients with MDSI, specifically exploring the potential clinical benefits of rapid reduction of depressive symptoms.
Methods
A Delphi panel consisting of practicing psychiatrists (n=12) from the US, Canada and EU was conducted between December 2020–June 2021. Panelists were screened to ensure they had sufficient experience with managing patients with MDD and MDSI. Panelists completed two survey rounds, and a virtual consensus meeting.
Results
This research confirmed current unmet needs in the treatment of patients with MDSI.
Hopelessness, functional impairment, worsening of MDD symptoms, recurrent hospitalization and higher risk of suicide attempt were considered as key consequences of the slow onset of action of oral antidepressants.
Treatment with rapid acting antidepressant was anticipated by panelists to provide short-term benefit such as rapid reduction of core MDD symptoms which may contribute to shorter hospital stays and improved patient engagement/compliance, allowing for earlier interventions and improved patient outcomes. For long-term benefits, panelists agreed that improved daily functioning and increased trust/confidence in treatment options, constitute key benefits of rapid-acting treatments
Conclusions
There is need for rapid-acting treatments which may help address key unmet needs and provide clinically meaningful benefits driven by the rapid relief of depressive symptoms particularly in patients with MDSI.
Disclosure
SB, ED, KJ, MO’H, QZ, MM, MH, SR, JA and DZ are employees of Janssen and hold stock in Johnson & Johnson Inc. AN is currently employed by Neurocrine Biosciences Inc. RP is an employee of Adelphi Values PROVE hired by Janssen.
Mental health and psychosocial support (MHPSS) staff in humanitarian settings have limited access to clinical supervision and are at high risk of experiencing burnout. We previously piloted an online, peer-supervision program for MHPSS professionals working with displaced Rohingya (Bangladesh) and Syrian (Turkey and Northwest Syria) communities. Pilot evaluations demonstrated that online, peer-supervision is feasible, low-cost, and acceptable to MHPSS practitioners in humanitarian settings.
Objectives
This project will determine the impact of online supervision on i) the wellbeing and burnout levels of local MHPSS practitioners, and ii) practitioner technical skills to improve beneficiary perceived service satisfaction, acceptability, and appropriateness.
Methods
MHPSS practitioners in two contexts (Bangladesh and Turkey/Northwest Syria) will participate in 90-minute group-based online supervision, fortnightly for six months. Sessions will be run on zoom and will be co-facilitated by MHPSS practitioners and in-country research assistants. A quasi-experimental multiple-baseline design will enable a quantitative comparison of practitioner and beneficiary outcomes between control periods (12-months) and the intervention. Outcomes to be assessed include the Kessler-6, Harvard Trauma Questionnaire and Copenhagen Burnout Inventory and Client Satisfaction Questionnaire-8.
Results
A total of 80 MHPSS practitioners will complete 24 monthly online assessments from May 2022. Concurrently, 1920 people receiving MHPSS services will be randomly selected for post-session interviews (24 per practitioner).
Conclusions
This study will determine the impact of an online, peer-supervision program for MHPSS practitioners in humanitarian settings. Results from the baseline assessments, pilot evaluation, and theory of change model will be presented.
Biomarkers may be useful endophenotypes for genetic studies if they share genetic sources of variation with the outcome, for example, with all-cause mortality. Australian adult study participants who had reported their parental survival information were included in the study: 14,169 participants had polygenic risk scores (PRS) from genotyping and up to 13,365 had biomarker results. We assessed associations between participants’ biomarker results and parental survival, and between biomarker results and eight parental survival PRS at varying p-value cut-offs. Survival in parents was associated with participants’ serum bilirubin, C-reactive protein, HDL cholesterol, triglycerides and uric acid, and with LDL cholesterol for participants’ fathers but not for their mothers. PRS for all-cause mortality were associated with liver function tests (alkaline phosphatase, butyrylcholinesterase, gamma-glutamyl transferase), metabolic tests (LDL and HDL cholesterol, triglycerides, uric acid), and acute-phase reactants (C-reactive protein, globulins). Association between offspring biomarker results and parental survival demonstrates the existence of familial effects common to both, while associations between biomarker results and PRS for mortality favor at least a partial genetic cause of this covariation. Identification of genetic loci affecting mortality-associated biomarkers offers a route to the identification of additional loci affecting mortality.
There is increasing concern regarding efficacy of organ preservation protocol in laryngeal and hypopharyngeal cancers.
Method
This study retrospectively assessed disease-related and functional outcomes of 191 patients with non-metastatic laryngeal or hypopharyngeal squamous cell carcinoma treated with curative intent (radiotherapy with or without chemotherapy).
Results
Seventy-six patients (39.8 per cent) had a primary cancer in the larynx, and 115 patients (60.2 per cent) had a primary cancer in the hypopharynx. The median follow up was 39 months. The 3-year time to progression, overall survival, local control and laryngectomy free survival was 56.2 per cent, 76.3 per cent, 73.2 per cent and 67.2 per cent, respectively. At the time of analysis, 83 patients (43.5 per cent) were alive and disease free at their last follow up and did not require tube feeding or tracheostomy. The laryngo-oesophageal dysfunction-free survival was 61 per cent at 3 years.
Conclusion
Organ conservation protocols remain the standard of treatment in appropriately selected patients with laryngeal and hypopharyngeal cancers.
Laryngotracheal reconstructive surgery very often requires placement of laryngeal stents, but most of the available stents either do not conform to the shape of the glottis or are open at the upper end, causing significant tissue reaction and aspiration. LT-Mold is an ideal stent in this respect, but it is not readily available.
Case report
The authors of this study fashioned a laryngeal stent out of a readily available Montgomery T-tube in such a way that it had a closed upper end and was well-conformed to the architecture of the larynx. This stent was used in a case of posterior expansion laryngoplasty, and post-operatively the patient had a patent airway with good voice and no aspiration.
Conclusion
A customised laryngeal stent is well tolerated and helps to solve complicated cases of posterior glottic stenosis.
This systematic review aims to identify published randomized controlled trials (RCTs) that evaluated the use of anticonvulsants for the prevention and/or treatment of delirium among older adults.
Methods:
A comprehensive search of databases: MEDLINE ALL (Ovid), Embase (Ovid), PsycINFO (Ovid), Web of Science Core Collection and Cochrane Central Register of Controlled was conducted.
Results:
The search identified four RCTs that evaluated the use of anticonvulsants among older adults with delirium. One RCT evaluated the perioperative use of gabapentin among individuals undergoing spinal surgery and the development of postoperative delirium. One RCT evaluated the relationship between the use of perioperative gabapentin and the development of postoperative delirium among individuals undergoing spinal surgery and hip and knee arthroplasty. Two post-hoc analyses of RCTs evaluated the use of gabapentin and pregabalin among individuals undergoing total knee arthroplasty (TKA) and total hip arthroplasty (THA). The perioperative use of gabapentin reduced the incidence of postoperative delirium among older adults undergoing spinal surgery. The perioperative use of gabapentin did not reduce the rates, severity or duration of postoperative delirium among older adults who were undergoing spine and hip and knee arthroplasty. The perioperative use of gabapentin did not reduce the incidence or duration of postoperative delirium among older adults undergoing elective TKA. The perioperative use of pregabalin did not reduce the incidence of postoperative delirium among older adults undergoing elective THA. Gabapentin and pregabalin were well tolerated among the individuals enrolled in these trials. There were no RCTs identified that evaluated the use of other anticonvulsants for the prevention and/or treatment of delirium among older adults.
Conclusions:
Based on current evidence, the routine use of anticonvulsants for the prevention and/or treatment of delirium among older adults cannot be recommended.
Mortality risk is known to be associated with many physiological or biochemical risk factors, and polygenic risk scores (PRSs) may offer an additional or alternative approach to risk stratification. We have compared the predictive value of common biochemical tests, PRSs and information on parental survival in a cohort of twins and their families. Common biochemical test results were available for up to 13,365 apparently healthy men and women, aged 17−93 years (mean 49.0, standard deviation [SD] 13.7) at blood collection. PRSs for longevity were available for 14,169 study participants and reported parental survival for 25,784 participants. A search for information on date and cause of death was conducted through the Australian National Death Index, with median follow-up of 11.3 years. Cox regression was used to evaluate associations with mortality from all causes, cancers, cardiovascular diseases and other causes. Linear relationships with all-cause mortality were strongest for C-reactive protein, gamma-glutamyl transferase, glucose and alkaline phosphatase, with hazard ratios (HRs) of 1.16 (95% CI [1.07, 1.24]), 1.15 (95% CI 1.04–1.21), 1.13 (95% CI [1.08, 1.19]) and 1.11 (95% CI [1.05, 1.88]) per SD difference, respectively. Significant nonlinear effects were found for urea, uric acid and butyrylcholinesterase. Lipid risk factors were not statistically significant for mortality in our cohort. Family history and PRS showed weaker but significant associations with survival, with HR in the range 1.05 to 1.09 per SD difference. In conclusion, biochemical tests currently predict long-term mortality more strongly than genetic scores based on genotyping or on reported parental survival.
Structural models of psychopathology consistently identify internalizing (INT) and externalizing (EXT) specific factors as well as a superordinate factor that captures their shared variance, the p factor. Questions remain, however, about the meaning of these data-driven dimensions and the interpretability and distinguishability of the larger nomological networks in which they are embedded.
Methods
The sample consisted of 10 645 youth aged 9–10 years participating in the multisite Adolescent Brain and Cognitive Development (ABCD) Study. p, INT, and EXT were modeled using the parent-rated Child Behavior Checklist (CBCL). Patterns of associations were examined with variables drawn from diverse domains including demographics, psychopathology, temperament, family history of substance use and psychopathology, school and family environment, and cognitive ability, using instruments based on youth-, parent-, and teacher-report, and behavioral task performance.
Results
p exhibited a broad pattern of statistically significant associations with risk variables across all domains assessed, including temperament, neurocognition, and social adversity. The specific factors exhibited more domain-specific patterns of associations, with INT exhibiting greater fear/distress and EXT exhibiting greater impulsivity.
Conclusions
In this largest study of hierarchical models of psychopathology to date, we found that p, INT, and EXT exhibit well-differentiated nomological networks that are interpretable in terms of neurocognition, impulsivity, fear/distress, and social adversity. These networks were, in contrast, obscured when relying on the a priori Internalizing and Externalizing dimensions of the CBCL scales. Our findings add to the evidence for the validity of p, INT, and EXT as theoretically and empirically meaningful broad psychopathology liabilities.
Subanesthetic ketamine infusion therapy can produce fast-acting antidepressant effects in patients with major depression. How single and repeated ketamine treatment modulates the whole-brain functional connectome to affect clinical outcomes remains uncharacterized.
Methods
Data-driven whole brain functional connectivity (FC) analysis was used to identify the functional connections modified by ketamine treatment in patients with major depressive disorder (MDD). MDD patients (N = 61, mean age = 38, 19 women) completed baseline resting-state (RS) functional magnetic resonance imaging and depression symptom scales. Of these patients, n = 48 and n = 51, completed the same assessments 24 h after receiving one and four 0.5 mg/kg intravenous ketamine infusions. Healthy controls (HC) (n = 40, 24 women) completed baseline assessments with no intervention. Analysis of RS FC addressed effects of diagnosis, time, and remitter status.
Results
Significant differences (p < 0.05, corrected) in RS FC were observed between HC and MDD at baseline in the somatomotor network and between association and default mode networks. These disruptions in FC in MDD patients trended toward control patterns with ketamine treatment. Furthermore, following serial ketamine infusions, significant decreases in FC were observed between the cerebellum and salience network (SN) (p < 0.05, corrected). Patient remitters showed increased FC between the cerebellum and the striatum prior to treatment that decreased following treatment, whereas non-remitters showed the opposite pattern.
Conclusion
Results support that ketamine treatment leads to neurofunctional plasticity between distinct neural networks that are shown as disrupted in MDD patients. Cortico-striatal-cerebellar loops that encompass the SN could be a potential biomarker for ketamine treatment.
The term right aortic arch is used for an aorta that arches over the right bronchus. Right aortic arch was classified into two types by Felson et al, based on branching patterns, with a proposed embryological explanation, and into three types by Shuford et al. Other anatomical variants of right aortic arch were described later, including isolated left brachiocephalic artery and aberrant left brachiocephalic artery. We have classified right aortic arch anatomy into 10 variants, supported by radiological evidence, and with reference to possible embryology. This classification will help in understanding the morphological basis for the formation of different types of right aortic arch and the course of the recurrent laryngeal nerve in such cases.