Genetic and environmental influences on rapid naming and reading ability: A twin study

The present study assesses the genetic and environmental etiologies of reading, rapid naming (RN), and their covariation by fitting multivariate structural equation models to data from 587 twin pairs in which at least one member of the pair exhibited reading difficulties (low-range) and from 360 control (normal-range) twin pairs who were tested in the Colorado Learning Disabilities Research Center. Results from a bivariate phenotypic analysis with two hypothesized latent factors, READ and RN, indicated that the correlation between reading and rapid naming performance for the low-range sample was significantly higher than that of the normal-range sample. When this model was partitioned to include estimates of genetic, shared environmental, and nonshared environmental influences, resulting heritability estimates did not differ significantly for the low-range and normal-range samples for either READ or RN. However, similar to the phenotypic correlation, the genetic correlation between the READ and RN latent factors could not be equated for the two groups. Thus, the etiology of the relationship between reading performance and rapid naming may differ for children with reading difficulties and normally-achieving readers. Moreover, these results support previous findings that the best predictors of reading skills may differ for samples of children with normal reading levels and those with reading difficulties.     

Teaching common errors in applying a procedure

This study investigated whether or not the teaching of matched examples and nonexamples in the form of common errors would improve student performance in applying a procedure to previously unencountered instances, and whether the common errors would be most beneficial in generality form, in example form, or in both forms. Participants were 141 first-year music students, who were randomly assigned to four groups and given the task to learn a procedure that was presented in a self-contained booklet. A pretest-posttest experimental design was used, with a prerequisite test given as a screening device. The two independent variables were the absence and presence of the common errors in the generality form and in the example form (2 x 2 factorial design). Results indicated that the teaching of common errors in the generality form significantly improved learning a procedure at the application level of behavior.     

Vocational-technical programs: follow-up of students with learning disabilities

Recent research has examined the role of vocational-technical training in facilitating the transition from school to work of adolescents with learning disabilities. The present study provided 6-, 12-, and 24-month follow-up data on such students who had attended vocational-technical programs. Matched groups of students without disabilities from vocational-technical programs, as well as randomly selected students without disabilities from regular high schools, were also included for comparisons. Results of the study raised several questions about the value and purpose of vocational-technical training for adolescents with learning disabilities.