In Latin America and the Caribbean, 240 million people, or 50 percent of the population, live in poverty. This report, written in Spanish, summarizes research by the Proyecto Costa Atlantica into the effects of such widespread poverty on the cognitive and social development of children. After an introduction on the general responses of the population and various governments to the oppressive economic conditions in these regions, the report discusses its approach to the two main themes underlying the research: quality of life and child development. Emphasis is placed on understanding how the individual constructs reality within his or her immediate, concrete environment, rather than on universal, biologically-dictated developmental trajectories. The report then describes various studies in areas such as: (1) the conceptions children from disadvantaged environments have about their world and life; (2) comprehension of emotions, leading to development of prosocial behaviors; (3) self-concept; and (4) the role of family and community in mitigating the effects of poverty. The report concludes with a discussion of issues left unresolved by the research. Includes a list summarizing the eight studies used in the report. Contains 36 references. (EV)