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Cortica

Editorial

Vol. 3 No. 2 (2024): La multidisciplinarité de la psychologie de la santé & des neurosciences

L'Elagage synaptique

  • Cherine Fahim Fahmy
DOI
https://doi.org/10.26034/cortica.2024.6091
Submitted
September 18, 2024
Published
2024-09-21

Abstract

Hebb (1949) proposed that synaptic strength between two neurons increases with simultaneous activity and that neuronal connections persist if they are used. This principle, known as synaptic pruning, is essential for brain development. Although the basic wiring of the brain is genetically predetermined, its adjustment over the course of life is influenced by experience. Brain maturation occurs primarily in response to environmental stimuli. The connections between neurons, or synapses, house our learning, experiences, and memories. Synapses continuously evolve: some are strengthened, while others weaken or disappear based on their usage.The first synaptic pruning during childhood is crucial for proper neuronal functioning. It eliminates unused synapses to reinforce those that are frequently used. This process continues throughout childhood and adolescence, playing a key role in neuroplasticity. During adolescence, the brain undergoes major reorganization, marked by a second synaptic pruning. This process involves eliminating less-used synapses to allow the development of more functional ones. Synaptic pruning at this stage is influenced by sex and stress hormones, which alter brain structure and connectivity, particularly in areas involved in decision-making, emotional regulation, and social cognition.

 

Toxic stress, without adequate support, can harm brain development. Identity is built through autobiographical memory, influenced by early relationships and the quality of bonds between adults and children. These relationships affect emotional regulation, autobiographical coherence, and executive functions, which are essential for a sense of identity and continuity. Early childhood experiences lay the foundation for brain architecture, essential for learning and well-being. Moderate stress, in a supportive environment, prepares children to face future challenges. In conclusion, synaptic pruning is fundamental for cognitive and socio-emotional development. It strengthens useful neuronal connections and eliminates unnecessary ones, thus influencing adaptability and resilience throughout life. During adolescence, this process is particularly important for refining neuronal networks in response to the social and emotional challenges characteristic of this period. Synaptic pruning sorts information to guide thought and action, fostering cognitive and behavioral adaptation. During this critical period, unused neuronal connections are eliminated, while actively used ones are strengthened, establishing the foundation for cognitive and socio-emotional skills throughout life. In conclusion, synaptic pruning is fundamental for the development of identity and thought, shaping neuronal networks based on experiences and social interactions, and influencing the capacity for adaptation and resilience in facing life's challenges.

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