Luke L. Sumberg

Digital social technologies, such as social media and online multiplayer video games (MVGs), have ushered in an era of peer relationships that evolve online, in addition to in person. This report reviews existing research about the dual role of social media and MVGs in shaping youth social connectedness, recognizing both their potential benefits and their associated risks on youth mental health. By providing evidence-based insights, it aims to inform strategies that optimize these technologies' advantages while safeguarding youth mental health and well-being. This report reviews peer-reviewed literature, clinical recommendations, reports, and surveys that assess youth usage of social media and MVGs and their associated psychological and physical health outcomes. Social media provides many opportunities for peer connection, including self-expression and social support, fostering positive social development and well-being. MVGs combine entertainment with collaboration, further strengthening social bonds. However, the use of these technologies has also been linked to negative outcomes, including social isolation, depression, anxiety, and sleep disorders. Publically-available, evidence-based resources can provide caregivers and professionals with guidance and clinical recommendations regarding youth social media and MVG use. Digital social technologies have become increasingly user-specific and immersive as the internet evolves and social media algorithms become more powerful. Additional research is required to understand how current youth usage of these technologies impacts physical and psychological outcomes. Future research should also investigate the differences in usage, outcomes, and the efficacy of treatments across youth sex and age.

Mild traumatic brain injury (mTBI) affects over 40 million people every year. One of its features includes the activation of microglia, the resident immune cells of the brain. Microglia assume different morphological states depending on their level of activation, such as surveilling ramified and activated hypertrophic, ameboid, and rod-like microglia. These states can be distinguished by multiple features, including the shape, span, and branching of microglia. Male Sprague–Dawley rats sustained mTBI using the Closed-Head Impact Model of Engineered Rotational Acceleration (CHIMERA) (3 times, 1.5 J per impact) or sham treatment. Four days after the injury, brains were collected and stained for microglia using the ionized calcium-binding adapter molecule-1 (Iba-1) antibody. Cortical injury sites were identified in a subset of CHIMERA animals. Using the MicrogliaMorphology ImageJ plugin and the MicrogliaMorphologyR package, 27 morphological features were quantified from individual microglia, and k-means clustering was used to classify microglia as ramified, rod-like, ameboid, and hypertrophic states. The CHIMERA injury altered microglia morphology features, which contributed to increased hypertrophic (activated) and decreased ramified (inactive) microglia compared to the sham controls. Combined with the clinically relevant mTBI paradigm and semi-automated/unbiased approach, the current findings may contribute to microglia morphology classification.