As a national support organization for parents of twins and higher order multiples, the National Organization of Mothers of Twins Clubs, Inc. (NOMOTC) has as its purpose the education of parents, teachers and other individuals having direct responsibility and interest in the special aspects of child development which relate to multiple birth…

This report is the outcome of a conference on the Utilization of International Twin Registries for Collaborative Research on Stress, Health, and Aging, held to consider the roles and limitations of twin and twin-family registries in a variety of studies concerned with behavior and health status with advancing age. (Author)

Solitary play in six kindergarten children was observed and coded for frequency and type in order to resolve iscrepancies in a Sex Birth Order interaction. Several facts concerning solitary play as indicative of independence and maturity are noted. (Author/ED)

Demonstrates some of the important factors that should be considered in research into the teaching techniques used with schizophrenic twins. (RB)

The purpose of this study is to clarify further the relationships among creative, cognitive, and affective production of students. Thirteen pairs of twins, eight monozygotic (MZ), five dyzygotic (DZ), were administered the Torrance Tests of Creative Thinking, MMPI, and Revised Beta Examination. The F ratio for testing significance of within-set…

Research shows a relationship between diagnoses of schizophrenia among twins. It was studied whether information that a twin was schizophrenic would bias diagnoses. Such information almost doubled the rater's estimates of probability of schizophrenia in a hypothetical case history. (NG)

In a twin study using direct behavioral observation of parent-child interaction, as well as ratings and experimental measures, the question of parents' differential treatment of monozygotic and dizygotic twins was investigated. (Author/SB)

This article reviews research regarding the effect of heredity on athletic performance. Research on twins indicates that genetic makeup may have a strong role in aerobic capacity, adaptability to training, composition of muscle tissue, and personality traits relating to competitiveness and leadership. (CB)

Taylor (1980) claims to show that the similarity in IQ between monozygotic twins reared apart found in prior studies is due to similarity in their environments. A reanalysis using Taylor's classification of environments but an alternative IQ measure shows that his findings do not constructively replicate. (Author/RD)

Summary scores for behaviors rated on Bayley's Infant Behavior Record were obtained by summing sequential ratings for same-sex twins participating in a longitudinal study. Composite scores were calculated for two behavioral clusters - one composed of behaviors related to primary cognitions and the other of behaviors related to extraversion.…

A geneticist discusses the heritability of intelligence and points out the pitcalls that lie in the path of those who try to estimate the heritability of IQ differences. (Editor)

Results are discussed in terms of Piaget's concept of the parallel development of the cognition of the impersonal and interpersonal worlds. (Authors)