Molecular mechanisms of brain plasticity: neurophysiologic and neuroimaging studies in the developing patients

The term plasticity, derived from the Greek word "plaistikos" meaning "to form" refers to the brain's ability to learn, remember and forget as well as its capacity to reorganize and recover from injury. There are four major types of plasticity: adaptive plasticity, impaired plasticity, excessive plasticity, and the 'Achilles heel' of the developing brain. Mechanisms of plasticity include: a change in the balance of excitation and inhibition; a long-term potentiation (LTP) or long-term depression (LTD); a change in neuronal membrane excitability; the anatomical changes-formation of new axon terminals and new synapses. Mechanisms for plasticity include activity-dependent refinement of neuronal connections and synaptic plasticity as a substrate for learning and memory. The molecular mechanisms for these processes were described in view of the current investigations. Authors presented: the role of calcium ions, calcium channels, NMDA receptors, free radicals, lipid peroxides and neurotrophins in the plasticity of developing brain. The utility of the neurophysiologic and MRI techniques were described in the determination of brain reorganization and repair in patients with cerebral palsy. Authors discussed their results on quantitative EEG and spectroscopy MRI studies in children with cerebral palsy. They have shown the existence of two processes in brain: brain damage and recovery.