Investigating Substance Use as a Coping Strategy Among Adolescent Psychiatric Inpatients: A Comparative Analysis Before and During the COVID-19 Pandemic.

The COVID-19 pandemic resulted in significant changes in daily life, potentially impacting mental health and substance use behavior. Research on COVID-related changes in adolescent substance use have yielded mixed findings. The current cross-sectional chart review study compared rates of past-year substance use before and during COVID-19 among adolescent psychiatric inpatients, and investigated how motives for coping with COVID-19 changes were related to psychiatric acuity, and past-year substance use. Count models assessed if the number of past-year days of alcohol and cannabis use was higher among adolescents (n = 491, 11-18 years, 61% female) hospitalized during COVID-19 (3/14/20 to 4/5/21) versus adolescents hospitalized before COVID-19 (8/30/2019 to 3/13/20). For a subsample of COVID-19 inpatients (n = 124; 75% female), we evaluated psychiatric correlates of endorsing substances to cope with COVID-19 changes/rules. Results indicated adolescents admitted during COVID-19 reported significantly more past-year alcohol and cannabis use days than adolescents admitted before COVID-19. Adolescents endorsed using alcohol (19%), cannabis (33%), and e-cigarettes/vaping (25%) to cope with COVID-19. E-cigarette/vaping to cope with COVID-19 was significantly related to lifetime suicide attempt. Endorsing alcohol or cannabis to cope with COVID-19 was associated with a significantly greater number of past-year use days for each respective substance. Adolescent psychiatric inpatients admitted during COVID-19 reported more substance use days than adolescents admitted before COVID-19. Using substances to cope was linked to psychiatric correlates (e.g., suicidality). Assessing the presence and function of substance use in this population may be important to identify, treat, and prevent compounding negative outcomes during times of community stress.

Resting state network connectivity is associated with cognitive flexibility performance in youth in the Adolescent Brain Cognitive Development Study.

Cognitive flexibility is an executive functioning skill that develops in childhood, and when impaired, has transdiagnostic implications for psychiatric disorders. To identify how intrinsic neural architecture at rest is linked to cognitive flexibility performance, we used the data-driven method of independent component analysis (ICA) to investigate resting state networks (RSNs) and their whole-brain connectivity associated with levels of cognitive flexibility performance in children. We hypothesized differences by cognitive flexibility performance in RSN connectivity strength in cortico-striatal circuitry, which would manifest via the executive control network, right and left frontoparietal networks (FPN), salience network, default mode network (DMN), and basal ganglia network. We selected participants from the Adolescent Brain Cognitive Development (ABCD) Study who scored at the 25th, ("CF-Low"), 50th ("CF-Average"), or 75th percentiles ("CF-High") on a cognitive flexibility task, were early to middle puberty, and did not exhibit significant psychopathology (n = 967, 47.9% female; ages 9-10). We conducted whole-brain ICA, identifying 14 well-characterized RSNs. Groups differed in connectivity strength in the right FPN, anterior DMN, and posterior DMN. Planned comparisons indicated CF-High had stronger connectivity between right FPN and supplementary motor/anterior cingulate than CF-Low. CF-High had more anti-correlated connectivity between anterior DMN and precuneus than CF-Average. CF-Low had stronger connectivity between posterior DMN and supplementary motor/anterior cingulate than CF-Average. Post-hoc correlations with reaction time by trial type demonstrated significant associations with connectivity. In sum, our results suggest childhood cognitive flexibility performance is associated with DMN and FPN connectivity strength at rest, and that there may be optimal levels of connectivity associated with task performance that vary by network.

Glutamate regulates neurite outgrowth of cultured descending brain neurons from larval lamprey.

In larval lamprey, descending brain neurons, which regenerate their axons following spinal cord injury, were isolated and examined in cell culture to identify some of the factors that regulate neurite outgrowth. Focal application of 5 mM or 25 mM L-glutamate to single growth cones inhibited outgrowth of the treated neurite, but other neurites from the same neuron were not inhibited, an effect that has not been well studied for neurons in other systems. Glutamate-induced inhibition of neurite outgrowth was abolished by 10 mM kynurenic acid. Application of high potassium media to growth cones inhibited neurite outgrowth, an effect that was blocked by 2 mM cobalt or 100 microM cadmium, suggesting that calcium influx via voltage-gated channels contributes to glutamate-induced regulation of neurite outgrowth. Application of glutamate to growth cones in the presence of 2 microM omega-conotoxin MVIIC (CTX) still inhibited neurite outgrowth, while CTX blocked high potassium-induced inhibition of neurite outgrowth. Thus, CTX blocked virtually all of the calcium influx resulting from depolarization. To our knowledge, this is the first direct demonstration that calcium influx via ligand-gated ion channels can contribute to regulation of neurite outgrowth. Finally, focal application of glutamate to the cell bodies of descending brain neurons inhibited outgrowth of multiple neurites from the same neuron, and this is the first demonstration that multiple neurites can be regulated in this fashion. Signaling mechanisms involving intracellular calcium, similar to those shown here, may be important for regulating axonal regeneration following spinal cord injury in the lamprey.