Philip L. Kilbride

Factors affecting the magnitude of the Ponzo perspective illusion among the Baganda

The magnitude of the Ponzo perspective illusion, utilizing stimuli with varying amounts of context, was determined for a population of Ugandan villagers. The subjects were classified as two-dimensional, three-dimensional, or mixed perceivers based upon their verbal responses to photographs portraying symbolic depth cues. The illusion magnitude among those subjects classified as three-dimensional was similar to that of college observers who demonstrate an increase in illusion magnitude with increasing background context. The two-dimensional observers’ responses were similar to those of villagers tested previously, showing no significant increase for the same conditions. The role of two-dimensional flatness cues was eliminated on the basis of a control experiment. The data are interpreted as reflecting the operation of a. cognitive factor determining responsiveness to symbolic depth cues in two-dimensional reproductions.

Child abuse and neglect—rare, but perhaps increasing, phenomena among the samia of Kenya

Abstract This study shows that child abuse and neglect as understood in the West are comparatively rare phenomena among the Samia of western Kenya. The existence of an extended family situation and a strong clan structure are importantly related to positive care accorded to children. However, due to increased migration to towns, socioeconomic change, and interethnic marriages, the clan unit has been eroded thus resulting in cases of child abuse and neglect. Several such cases are reported in this study. The Samia traditionally practice the “evil eye” which is here considered to be a form of child abuse. Our findings, therefore, also have implications for previous efforts to define child abuse cross-culturally.

THE PONZO ILLUSION AMONG THE BAGANDA OF UGANDA

Many cross-cultural studies have demonstrated that individuals from various cultural groups differ in their susceptibility t o visual illusions. Such studies date back t o that of Rivers in 1901.’ The most recent comprehensive study is by Segall, Campbell, and Herskovits, who showed a marked effect of culture on illusion magnitude.2 Some of the better researched illusions, all of which are seemingly affected by cultural factors, include the trapezoidal i l l ~ s i o n , ~ the Muller-Lyer and horizontal-vertical illusions,2 i4 , 5 and the Ponzo perspective i l l ~ s i o n . ~ ~ To date, however, no satisfactory explanation for group differences in illusion susceptibility enjoys universal support among contemporary researchers in this field. The most commonly discussed theory is the “ecological hypothesis,” which assumes that the influence of cues involved in producing an illusion depends ultimately upon a n individual’s history of exposure t o the particular cues in question.2 For example, exposure t o such “carpentered” stimuli as street corners, square rooms, or other angular material artifacts is thought t o be responsible for the effect seen with the Muller-Lyer figure. Environments rich in perspective (e.g., roads, railway tracks) or those that contain a broad open vista are hypothesized t o produce an illusion response t o the Ponzo and the horizontal-vertical illusions, respectively. Unfortunately, empirical findings do not always lend support t o a simple causal relationship between environmental experience and perception. Such factors as mode of presentation, cognitive style, child-rearing patterns, retinal pigmentation, and sex are correlated with susceptibility t o visual illusions.’ Of particular interest t o the present paper are the many studies that show that cross-cultural differences also exist in the perception of pictorial depth cues such as perspective, object-size, and superimposition.’ That is, individuals in cultures where exposure to reading materials, photographs, and representational art is limited or nonexistent are not generally cognizant of the symbolic cues that in our culture serve t o indicate depth or distance on a two-dimensional pictorial surface. Growing up in a “pictureless environment” typically results in a cognitive disposition t o view pictures in only two dimensions (perception of the “real world,” of course, is three-dimensional, as in our own culture). The implications of these data for cross-cultural research involving visual illusions are profound for the following reasons: (1) the spatial

Anti anti‐universalism: Rethinking cultural psychology as anti anti‐relativism 1

Shweder, Richard A. Thinking through Cultures: Expeditions in Cultural Psychology. Cambridge: Harvard University Press, 1991. vii + 404 pp. including notes, references, and index.

Solitaire and solidaire: Ethnographic introspections on freedom in nature and culture

34.95 cloth,

Piaget in Africa: Some thoughts concerning operational thinking among the Iteso

15.95 paper. Stigler, James W., Shweder, Richard A., and Herdt, Gilbert, eds. Cultural Psychology: Essays on Comparative Human Development. Cambridge: Cambridge University Press. 1990. ix + 625 pp. including chapter references and indices.

Sensorimotor Behavior of Baganda and Samia Infants A Controlled Comparison

59.50 cloth,

The comparative motor development of Baganda, American white, and American black infants.

19.95 paper.

Sociocultural Factors and the Early Manifestation of Sociability Behavior Among Baranda Infants

Paul Riesman. Freedom in Fulani Social Life: An Introspective Ethnography. Translated from the French by Martha Fuller. Chicago: The University of Chicago Press, 1977. xiii + 297 pp. Notes, glossary and index of Fulani terms, bibliography, general index, illustrations.

Introduction: The Socialization of Affect

25.00.