Rice D C
U.S. Environmental Protection Agency, Office of Research and Development, National Center for Environmental Assessment, Washington, D.C., USA.
Environ Health Perspect. 2000 Jun;108 Suppl 3(Suppl 3):405-8. doi: 10.1289/ehp.00108s3405.
Attention deficit hyperactivity disorder (ADHD) is a disability that affects between 3 and 7% of children, with a significant number of individuals continuing to be affected into adolescence and adulthood. ADHD is characterized in part by an inability to organize complex sequences of behavior, to persist in the face of distracting stimuli, and to respond appropriately to the consequences of past behavior. There are some parallels between the features of ADHD and the behavior of monkeys exposed developmentally to lead or polychlorinated biphenyls (PCBs), as evidenced by research from our laboratory. Both lead and PCB exposure produce deficits on discrimination reversal and spatial delayed alternation performance; treated monkeys exhibit deficits in their ability to change an already established response strategy and inhibit inappropriate responses. Monkeys exposed developmentally to lead or PCBs also perform differently from control monkeys on a fixed interval schedule of reinforcement, which requires the temporal organization of behavior using only internal cues. Whereas the etiology of ADHD is multifactorial, the possibility that neurotoxic agents in the environment contribute to the incidence of ADHD warrants attention.
注意力缺陷多动障碍（ADHD）是一种影响3%至7%儿童的疾病，相当数量的个体在进入青春期和成年期后仍受其影响。ADHD的部分特征是无法组织复杂的行为序列，在面对干扰刺激时难以坚持，以及对过去行为的后果做出适当反应。我们实验室的研究表明，ADHD的特征与发育过程中接触铅或多氯联苯（PCBs）的猴子的行为有一些相似之处。铅和PCB暴露都会导致辨别逆转和空间延迟交替表现方面的缺陷；接受治疗的猴子在改变已建立的反应策略和抑制不适当反应的能力上存在缺陷。在仅使用内部线索进行行为时间组织的固定间隔强化时间表上，发育过程中接触铅或PCBs的猴子与对照猴子的表现也有所不同。虽然ADHD的病因是多因素的，但环境中的神经毒性物质导致ADHD发病率上升的可能性值得关注。
