White matter, composed of myelinated nerve fibers, plays a crucial role in cognitive function, learning, and psychiatric disorders. Myelin, once associated with demyelinating diseases like multiple sclerosis, is now recognized as a key factor in various psychiatric conditions, including depression and schizophrenia. Myelination continues into adulthood and is influenced by experience, affecting information processing by regulating impulse conduction speed and synchronization between brain regions. Research indicates that myelin is involved in normal cognitive function and learning, and its regulation by impulse activity and environmental experience is a dynamic process. Studies show that myelin gene variations are linked to schizophrenia, depression, and other psychiatric disorders. Postmortem brain tissue analysis reveals reduced myelin gene expression in patients with schizophrenia, depression, and bipolar disorder. Non-invasive brain imaging techniques have identified structural differences in white matter tracts associated with various neurological and psychiatric conditions, including autism, dyslexia, and ADHD. Myelin disorders can lead to paralysis, sensory-motor dysfunction, cognitive impairment, and mental retardation. Myelin damage can result from autoimmune diseases, genetic disorders, metabolic conditions, infections, and trauma. Myelin is also involved in synaptic plasticity and learning, with myelin proteins inhibiting axon sprouting and limiting the critical period for synaptic plasticity. Myelin regulation of conduction velocity is influenced by axon diameter, myelin sheath thickness, and the number and spacing of nodes of Ranvier. Myelin plasticity is influenced by environmental experience, with enriched environments increasing myelination in the brain. Myelin can change in response to activity, with myelination processes being regulated by molecular mechanisms involving ATP release and purinergic signaling. Myelin also affects synaptic function and information processing, with myelin proteins directly controlling synapse formation and inhibiting axon sprouting. Research highlights the importance of myelin in cognitive development and learning, with myelin changes detected in individuals with schizophrenia and other disorders. Myelin plasticity is a dynamic process that continues into adulthood, with myelin regulation playing a role in neural synchrony and information processing. Myelin's role in synaptic plasticity and cognitive function is increasingly recognized, with implications for understanding and treating psychiatric and neurological disorders.White matter, composed of myelinated nerve fibers, plays a crucial role in cognitive function, learning, and psychiatric disorders. Myelin, once associated with demyelinating diseases like multiple sclerosis, is now recognized as a key factor in various psychiatric conditions, including depression and schizophrenia. Myelination continues into adulthood and is influenced by experience, affecting information processing by regulating impulse conduction speed and synchronization between brain regions. Research indicates that myelin is involved in normal cognitive function and learning, and its regulation by impulse activity and environmental experience is a dynamic process. Studies show that myelin gene variations are linked to schizophrenia, depression, and other psychiatric disorders. Postmortem brain tissue analysis reveals reduced myelin gene expression in patients with schizophrenia, depression, and bipolar disorder. Non-invasive brain imaging techniques have identified structural differences in white matter tracts associated with various neurological and psychiatric conditions, including autism, dyslexia, and ADHD. Myelin disorders can lead to paralysis, sensory-motor dysfunction, cognitive impairment, and mental retardation. Myelin damage can result from autoimmune diseases, genetic disorders, metabolic conditions, infections, and trauma. Myelin is also involved in synaptic plasticity and learning, with myelin proteins inhibiting axon sprouting and limiting the critical period for synaptic plasticity. Myelin regulation of conduction velocity is influenced by axon diameter, myelin sheath thickness, and the number and spacing of nodes of Ranvier. Myelin plasticity is influenced by environmental experience, with enriched environments increasing myelination in the brain. Myelin can change in response to activity, with myelination processes being regulated by molecular mechanisms involving ATP release and purinergic signaling. Myelin also affects synaptic function and information processing, with myelin proteins directly controlling synapse formation and inhibiting axon sprouting. Research highlights the importance of myelin in cognitive development and learning, with myelin changes detected in individuals with schizophrenia and other disorders. Myelin plasticity is a dynamic process that continues into adulthood, with myelin regulation playing a role in neural synchrony and information processing. Myelin's role in synaptic plasticity and cognitive function is increasingly recognized, with implications for understanding and treating psychiatric and neurological disorders.