understate the burden. Social isolation and stigma often add to the medical and financial burden borne by patients and their families.
Although numerous and diverse, the neurological, psychiatric, and developmental disorders addressed by this report share several important features. First, they are increasingly recognized as disorders of the brain and its neural connections that are precipitated by injury, psychological trauma, chronic adversity, or genetic vulnerability. Several psychiatric disorders, including schizophrenia, are now understood to have a strong biological component, while disabling psychiatric symptoms are known to result from neurological diseases, as when depression follows stroke.2 Indeed, integrated knowledge of psychiatry and neurology now holds promise for greatly improving medical care for illnesses affecting the brain.[1,2] Thus, throughout this report, neurological, psychiatric, and developmental disorders are collectively referred to as brain disorders. The aggregate examination of these disorders not only reflects their common systemic origins, but also represents a strategy that can leverage the limited resources available to provide the widest possible benefit in developing countries.
Many of these disorders are chronic, debilitating conditions. Programs and research show that much of the disability associated with these disorders can be prevented or reduced through effective, affordable measures. As discussed in Chapter 2, poverty frequently accompanies and exacerbates the proximal causes of brain disorders. Thus people in low-income countries face increased risk of developing these disorders. This report is therefore intended to call attention not only to the serious toll exacted by brain disorders in low- and middle-income countries, but also to the significant potential for reducing that impact through cost-effective measures.
While recognition of common features among brain disorders should inform efforts to reduce their impact, it will also be necessary to develop targeted strategies for the prevention and treatment of specific illnesses and rehabilitation for those who suffer from them. The committee's contribution to this endeavor appears in Part II of this report, whose chapters focus on six classes of brain disorders: developmental disabilities, epilepsy, schizophrenia, bipolar disorder, unipolar depression, and stroke. Other brain disorders contributing to the burden of disease in developing countries but not among the disorders discussed in Part II include Alzheimer's disease, addictive disorders, HIV encephalopathy, meningitis, peripheral neuropathies, autism, posttraumatic stress disorder, cerebral palsy, dementia, and Parkinson's disease.