Brain damage can be induced by a variety of initial insults, including traumatic brain injury (caused by external physical forces, blast shock wave or high energy projectiles), stroke (ischemic and hemorrhagic stroke), poisoning with hazardous chemicals (organophosphate pesticides, chemical warfare agents, toxic substances, alcohol, drugs, etc.), infection by pathogenic microbes (HIV virus, bacteria, microorganisms, biological threat agents, etc.), brain tumors (gliomas, meningiomas, pituitary adenomas and nerve sheath tumors), and degenerative diseases (Parkinson's, Alzheimer's, ALS, Chorea, Huntingtons, Dementia, etc.) in the brain. Brain damage is a serious public health problem, which results in the losses of many years of productive life and incurs large healthcare costs. Much of the damage done to the brain does not typically occur at the time of initial insult and does not result directly from the initial insult itself. A cascade of progressive neuronal cell death, neural loss and axonal degeneration is triggered by the initial insults and possibly continues in the hours, days, weeks or months following the initial insults. The progressive neuronal cell death and neural injury are defined as secondary neuronal damage. This delayed secondary damage has come to be recognized as a major contributor to long-term neuropsychiatric and neurological disorders. Because chronic disability resulting from brain damage is largely attributable to mental sequelae rather than focal motor or sensory neurological deficits in humans, neuropsychiatric disorders should be the long-term prominent clinical manifestations of the victims of brain damage. Secondary neuronal damage in some specific regions of the brain (such as the hippocampus, amygdale, thalamus, piriform cortex, and cortex) has been identified as being responsible for these chronic neuropsychiatric disorders.

Brain damage-induced chronic neuropsychiatric disorders may include persistent memory and cognitive deficits (memory loss, forgetfulness, learning disabilities, concentration difficulties, etc.), non-specific mental and emotional symptoms (depression, aggression, stress, anxiety, insomnia, headache, fatigue, mood swings, increased emotional sensitivity, etc.), posttraumatic stress disorder (persistent re-experiencing, avoidance and hyperarousal symptoms), psychomotor performance deficits (impaired fine psychomotor dexterity, reduced visuo-spatial abilities, and deficits in motor function and coordination), and other behavioral problems.

In this research topic, emphasis will be placed on 1) neuropsychiatric disorders caused by various brain insults in humans and experimental animals; 2) the involvement of secondary neuronal damage in the development of chronic neuropsychiatric disorders; and 3) the similarities and differences among the neuropsychiatric signs and symptoms induced by different brain insults. We call for researchers and academicians engaged in brain insult, secondary neuronal damage and neuropsychiatric disorder research, to contribute original research article, review article, clinical case study, hypothesis and theory article, method article, opinion article, or technology report to this research topic.

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