Development of Cerebellar Reserve.

The cerebellar reserve is defined as the capacity of the cerebellum for compensation and restoration following injury. This unique cerebellar ability is attributed to various forms of synaptic plasticity that incorporate multimodal and redundant cerebellar inputs, two major features of the cerebellar circuitry. It is assumed that the cerebellar reserve is acquired from the age of 12 years after the maturation of both the cerebellar adaptative behaviors and cerebellar functional connectivity. However, acquiring the cerebellar reserve is also affected by two other factors: vulnerability and growth potential in the developing cerebellum. First, cerebellar injury during the critical period of neural circuit formation (especially during fetal and neonatal life and infancy) leads to persistent dysfunction of the cerebellum and its targets, resulting in the limitation of the cerebellar reserve. Secondly, growth potential appears to facilitate cerebellar reserve during the stage when the cerebellar reserve is still immature. Based on these findings, the present mini-review proposes a possible developmental trajectory underlying the acquisition of cerebellar reserve. We highlight the importance of studies dedicated to the understanding of the cerebellar resilience to injuries.