How does experience shape the brain and both cause and repair stress disorders?

From Healing Resources Info:

At birth, the brain, which is command central for the body, is its most undifferentiated organ with a plasticity that enables the brain to create new neural circuitry throughout life. New brain imaging resources including electroencephalogram (EEG), quantitative EEG studies (QEEG), positron emission tomography (PET), single photon emission computed tomography (SPECT) and functional MRI (fMRI) show us that throughout life, the brain remains capable of renewing its structure and function and does so as a result of experience—especially social experience. The traumatic neural dysregulation caused by early life trauma mirrors that of traumatic dysregulations caused by overwhelming events experienced later in life. Stress symptoms range from those of PTSD, to depression, anxiety, learning problems, social disorders and chronic physical health problems.

A child’s brain is so socially attuned that unspoken communication shapes its development to a remarkable degree. The brain’s amazing plasticity at this stage of development sets a lifelong template for thoughts, feelings, behavior –and a variety of stress related disorders. Moreover, because the brain remains flexible throughout life, nonverbal communication retains the capacity to change. Studies in people over age ninety show us images of mature brains that continue to produce new neural pathways at a time when older pathways are dying. The same experiential and social factors that profoundly shape the brain initially can also be instrumental in repairing the causes and symptoms of stress related disorders.