Special section on theoretical models and conceptual analyses: second installment

The Journal of Applied Psychology's call for theoretical models and conceptual analyses brought a terrific response. The first set of articles accepted in response to the call appeared in the December 2004 issue. This installment contains the second set of articles.     

Age changes in the missing-letter effect revisited

When participants search for a target letter while reading, they make more omissions if the target letter is embedded in frequent function words than in less frequent content words. Reflecting developmental changes in component language and literacy skills, the size of this effect increases with age. With adults, the missing-letter effect is due to both word function and word frequency. With children, it is unclear whether the growing size of the missing-letter effect across development is due to a larger effect of word function, word frequency, or both because previous studies with children seeking to isolate the influence of word frequency and word function suffer from important methodological limitations. With these methodological limitations eliminated (Experiments 1 and 2), performance in a letter detection task was assessed for children in Grades 1, 2, 3, 4, and 7 as well as for undergraduate students. The results revealed that the influence of word function increases with age, whereas the effect of frequency is fairly stable across ages. Furthermore, normative predictability data collected in Experiment 3 revealed that third graders and undergraduate students were equally good at predicting function slots in a sentence.     

Significance of Childhood Conduct Problems to Later Development of Conduct Disorder Among Children With ADHD: A Prospective Follow-Up Study

This study investigates whether low to moderate levels of childhood oppositional defiant disorder (ODD) and conduct disorder (CD) behaviors contribute to the development of clinically diagnosed CD in adolescence, in children with attention deficit hyperactivity disorder (ADHD). Participants were 207 White boys (ages 6-12) with ADHD free of conduct disorder diagnoses. Parent and teacher ratings were obtained. Participants were assessed at mean age 18 by clinicians blind to childhood status. A non-ADHD group (recruited in adolescence) was also studied. ODD behavior ratings did not predict CD in adolescence, whereas CD behavior ratings did. No single ODD or CD behavior predicted adolescent outcome. ADHD probands with very low ratings (Not at all, Just a little) by parents and teachers on all CD behaviors were still at significantly increased risk for CD in adolescence, compared to non-ADHD controls. The same relationships were found between childhood ODD and CD behaviors, and antisocial personality disorder in adulthood (mean age, 25). We conclude that childhood ADHD is a developmental precursor of later antisocial disorder, even in the absence of comorbid ODD or CD in childhood. However, low levels of CD-type problems are not innocuous, because they predict later CD among children with ADHD without comorbid CD.     

Direct assessments of the processing time hypothesis for the missing-letter effect

When participants search for a target letter while reading, they make more omissions if the target letter is embedded in frequently used words or in the most frequent meaning of a polysemic word. According to the processing time hypothesis, this occurs because familiar words and meanings are identified faster, leaving less time for letter identification. Contrary to the predictions of the processing time hypothesis, with a rapid serial visual presentation procedure, participants were slower at detecting target letters for more frequent words or the most frequent meaning of a word (Experiments 1 and 2) or at detecting the word itself instead of a target letter (Experiment 3). In Experiments 4 and 5, participants self-initiated the presentation of each word, and the same pattern of results was observed as in Experiments 1 and 3. Positive correlations were also found between omission rate and response latencies.     

Technology for independence: a community-based resource center

Despite the prominence of the disability civil rights model--with its values of inclusion and empowerment--the majority of social and policy research conducted to date has not sufficiently included the perspective of persons with disabilities in the research process and as uniquely qualified researchers themselves. This article describes a new project, "Technology for Independence: A Community-Based Resource Center" (CBRC). Over a five-year period, the CBRC will attempt to enhance community and consumer-directed disability organizations to design, implement, and disseminate research that promotes access to and use of assistive technology (AT). The CBRC will use strategies such as leadership training, participatory action research, technical assistance, web-assisted training, and annual symposia. A primary goal of the CBRC is to increase the capacity of community organizations to conduct research on AT that is scientifically rigorous and relevant to disability services, policy, and law.     

Patients' versus informants' reports of personality disorders in predicting 7 1/2-year outcome in outpatients with depressive disorders

Concordance between patients' and informants' reports of personality disorders (PDs) is low, raising the questions of which source provides more valid data and whether both contribute unique information. This study compared patients' and informants' reports of PDs in predicting outcome in a 7 1/2-year follow-up of 85 depressed outpatients. Patients and informants were independently evaluated using structured interviews; outcome was assessed using structured interviews with patients. Both patients' and informants' reports of PD diagnoses and dimensional scores independently predicted depression symptoms and global functioning at follow-up. However, only informants' reports made a unique contribution to predicting social adjustment. This finding indicates that both patients and informants provide unique information on Axis II psychopathology and argues for the use of both sources in the assessment of PDs.     

Influence of parafoveal processing on the missing-letter effect

According to the parafoveal-processing hypothesis, letters are more often missed in function words than in content words because the former are more likely to be identified in the parafovea, where letter processing is not available. Contrary to previous demonstrations, more omissions occurred in function words than in content words when parafoveal processing was not available because words were displayed in column format, text was read through a 5-letter window, or words were presented 1 at a time on a computer screen. In all experiments, impeding parafoveal processing decreased omission rates for function but not for content words. In the last experiment, direct monitoring of eye movements revealed that, for both fixated and skipped words, letters in function words are missed more often than content words. These results are best interpreted within a model including the structural precedence hypothesis and stressing the importance of visual factors.