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Executive functions (EFs) in early childhood are predictors of later developmental outcomes and school readiness. Much of the research on EFs and their psychosocial correlates has been conducted in high-income, minority world countries, which represent a small and biased portion of children globally. The aim of this study is to examine EFs among children aged 3-5 years in two African countries, South Africa (SA) and The Gambia (GM), and to explore shared and distinct predictors of EFs in these settings. The SA sample (N = 243, 51.9% female) was recruited from low-income communities within the Cape Town Metropolitan area. In GM, participants (N = 171, 49.7% female) were recruited from the rural West Kiang region. EFs, working memory (WM), inhibitory control (IC) and cognitive flexibility (CF), were measured using tablet-based tasks. Associations between EF task performance and indicators of socioeconomic status (household assets, caregiver education) and family enrichment factors (enrichment activities, diversity of caregivers) were assessed. Participants in SA scored higher on all EF tasks, but children in both sites predominantly scored within the expected range for their age. There were no associations between EFs and household or familial variables in SA, except for a trend-level association between caregiver education and CF. Patterns were similar in GM, where there was a trend-level association between WM and enrichment activities but no other relationships. We challenge the postulation that children in low-income settings have poorer EFs, simply due to lower socioeconomic status, but highlight the need to identify predictors of EFs in diverse, global settings.

Background: Electroconvulsive therapy (ECT) is the most effective acute treatment for severe depression, but there are concerns about its adverse cognitive effects. ECT may impair cognition through stimulation of glutamate receptors, and preliminary evidence has suggested that ketamine, a glutamate antagonist, may alleviate these effects. Ketamine has been shown to have a rapid, but temporary, antidepressant effect after a single infusion. Objective: To determine the efficacy and safety of adjunctive low-dose ketamine to reduce cognitive impairments caused by ECT and, secondarily, to improve symptomatic outcome. Design: Multicentre, two-arm, parallel-group, patient-randomised, placebo-controlled superiority trial. Setting: Eleven ECT suites based in seven NHS trusts in the north of England. Participants: Severely depressed hospitalised patients or outpatients who received ECT as part of their usual clinical care. Interventions: Patients were randomised to ketamine (0.5 mg/kg) or saline as an adjunct to their anaesthetic for their ECT course in a 1 : 1 ratio. Main outcome measures: The primary outcome was delayed verbal recall on the Hopkins Verbal Learning Task – Revised (HVLT-R) after four ECT treatments (mid-ECT), analysed using a Gaussian repeated measures model. Secondary outcomes included autobiographical, working and visual memory and verbal fluency, symptoms and quality of life; assessments occurred at mid-ECT, end of treatment and 1 and 4 months after the last ECT. Neuropsychological function was compared with that of healthy control subjects and a functional near-infrared spectroscopy (fNIRS) substudy investigated prefrontal cortex function. A patient survey of study participation was carried out. Results: Seventy-nine severely depressed patients were randomised to ketamine (0.5 mg/kg) or saline as an adjunct to their anaesthetic for their ECT course; the modified intention-to-treat sample included 70 patients. Compared with saline, adjunctive ketamine had no significant effect on HVLT-R delayed recall [treatment effect difference –0.43, 95% confidence interval (CI) –1.73 to 0.87], other neuropsychological outcomes, improvement in depression [difference in Montgomery–Åsberg Depression Rating Scale (MADRS) score of 0.44, 95% CI –1.03 to 1.91], the number of ECT treatments to remission (MADRS score of ≤ 10: 0.83, 95% CI –3.2 to 4.9), anxiety symptoms or quality of life. By the end of ECT treatment, 37% (saline 35%, ketamine 39%) of patients had remitted. Tolerability was similar in the two treatment arms; two patients had isolated transient psychological effects attributable to ketamine. Preliminary fNIRS analysis found that patients had blunted prefrontal cortical haemodynamic responses compared with control subjects during a verbal fluency task at baseline; this was further diminished at mid-ECT without modulation by ketamine. Greater haemodynamic responsivity to ECT appeared to be associated with a better clinical response. The majority of patients surveyed reported a positive experience of study participation. Conclusions: The results of the study do not support the use of adjunctive ketamine in routine ECT treatment in the NHS. Although no evidence of benefit was found for ketamine, moderate benefits or harms cannot be excluded, as recruitment was

Multimodal monitoring of brain state is important both for the investigation of healthy cerebral physiology and to inform clinical decision making in conditions of injury and disease. Near-infrared spectroscopy is an instrument modality that allows non-invasive measurement of several physiological variables of clinical interest, notably haemoglobin oxygenation and the redox state of the metabolic enzyme cytochrome c oxidase. Interpreting such measurements requires the integration of multiple signals from different sources to try to understand the physiological states giving rise to them. We have previously published several computational models to assist with such interpretation. Like many models in the realm of Systems Biology, these are complex and dependent on many parameters that can be difficult or impossible to measure precisely. Taking one such model, BrainSignals, as a starting point, we have developed several variant models in which specific regions of complexity are substituted with much simpler linear approximations. We demonstrate that model behaviour can be maintained whilst achieving a significant reduction in complexity, provided that the linearity assumptions hold. The simplified models have been tested for applicability with simulated data and experimental data from healthy adults undergoing a hypercapnia challenge, but relevance to different physiological and pathophysiological conditions will require specific testing. In conditions where the simplified models are applicable, their greater efficiency has potential to allow their use at the bedside to help interpret clinical data in near real-time.

This study examined the brain bases of early human social cognitive abilities. Specifically, we investigated whether cortical regions implicated in adults' perception of facial communication signals are functionally active in early human development. Four-month-old infants watched two kinds of dynamic scenarios in which a face either established mutual gaze or averted its gaze, both of which were followed by an eyebrow raise with accompanying smile. Haemodynamic responses were measured by near-infrared spectroscopy, permitting spatial localization of brain activation (experiment 1), and gamma-band oscillatory brain activity was analysed from electroencephalography to provide temporal information about the underlying cortical processes (experiment 2). The results revealed that perceiving facial communication signals activates areas in the infant temporal and prefrontal cortex that correspond to the brain regions implicated in these processes in adults. In addition, mutual gaze itself, and the eyebrow raise with accompanying smile in the context of mutual gaze, produce similar cortical activations. This pattern of results suggests an early specialization of the cortical network involved in the perception of facial communication cues, which is essential for infants' interactions with, and learning from, others. [ABSTRACT FROM AUTHOR]