Ashley Kim¹, Aron Elias², Jalyn Huang³#

¹ Leonia High School

² Texas Academy of Mathematics and Science

³ Irvine High School

#Advisor

ABSTRACT

Synaptic pruning is a developmental process that eliminates weaker synapses while strengthening essential connections, optimizing brain function across regions such as the hippocampus, sensory cortex, and prefrontal cortex (Rowden, 2023; Faust et al., 2021; Hathaway & Newton, 2023). This process is shaped by both experience-expectant inputs, like vision and hearing, and experience-dependent events unique to each individual (From Neurons to Neighborhoods, 2000). Disruptions caused by early-life stressors, including neglect, poverty, and violence, alter microglial activity and complement protein regulation, resulting in either excessive or impaired pruning and distinct patterns of connectivity (Teicher & Samson, 2016; Zhang et al., 2024). Molecular mechanisms such as microglial engulfment, complement cascades, and dopamine signaling are essential in maintaining pruning balance, and errors in proteins like C4 and Drd2 have been linked to schizophrenia, autism, and anxiety (Sheridan et al., 2022; Zhang et al., 2023; Ju et al., 2017). Current research highlights therapeutic strategies, including complement inhibition, gene editing, and anti-inflammatory treatments, though these approaches must address ethical and developmental challenges to preserve normal brain maturation (Mansur et al., 2021; Dayananda et al., 2022). Together, these findings underscore the complexity of synaptic pruning and its central role in cognition, emotion, and the emergence of psychiatric disorders.

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