The investment theory of Cattell supposes an influence of fluid on crystallized intelligence. The development of fluid intelligence largely depends on biological factors, of crystallized intelligence on fluid intelligence and environmental stimulation. To test this theory two contrasting samples representing a broad ability range were chosen, a…

Reading acquisition requires, in addition to appropriate phonological abilities, accurate and rapid selection of sublexical orthographic units by attentional letter string parsing. Spatio-temporal distribution of attentional engagement onto 3-pseudoletter strings was studied in 28 dyslexic and 55 normally reading children by measuring attentional…

There has been a recent upsurge of interest in exploring how choices of methods and timing of instruction affect the rate and persistence of learning. The authors review three lines of experimentation--all conducted using educationally relevant materials and time intervals--that call into question important aspects of common instructional…

The extensive use of survey instruments in the social sciences has long created debate and concern about validity of outcomes, especially among instruments that gather ordinal-level data. Ordinal-level survey measurement of concepts that could be measured at the interval or ratio level produce errors because respondents are forced to truncate or…

Variable reinforcement schedules are used to arrange the availability of reinforcement following varying response ratios or intervals of time. Random reinforcement schedules are subtypes of variable reinforcement schedules that can be used to arrange the availability of reinforcement at a constant probability across number of responses or time.…

Background: A meta-analysis examined the effects of deinstitutionalisation on adaptive behaviour outcomes in persons with intellectual disability. The need for an updated review in this area is reflected by recent policy shifts in community care practices and the international status of deinstitutionalisation efforts. Method: Twenty-three studies…

Students' endorsement of different characteristics associated with social success (sincere, responsible, dominant, disingenuous behaviors, appearance/athletic characteristics) were examined at six-month intervals for four time points spanning the transition from elementary to middle school (N = 558; 53% girls, 47% boys; 56% African American, 44%…

Does the choice of test for assessing reading comprehension influence the outcome of genetic analyses? A twin design compared two types of reading comprehension tests classified as primarily associated with word decoding (RC-D) or listening comprehension (RC-LC). For both types of tests, the overall genetic influence is high and nearly identical.…

Typical assessments of temporal discounting involve presenting choices between hypothetical monetary outcomes. Participants choose between smaller immediate rewards and larger delayed rewards to determine how the passage of time affects the subjective value of reinforcement. Few studies, however, have compared such discounting to actual…

Objective: In recent years cohort studies have examined childhood attention-deficit/hyperactivity disorder (ADHD) as a risk factor for substance use disorders (SUDs) in adolescence and young adulthood. The long-term risk is estimated for development of alcohol, cannabis, combined alcohol and psychoactive SUDs, combined SUDs (nonalcohol), and…

Purpose: To identify racial/ethnic differences in retention of older adults at 3 levels of participation in a prospective observational study: telephone, in-home assessments, and home visits followed by blood draws. Design and Methods: A prospective study of 1,000 community-dwelling Medicare beneficiaries aged 65 years and older included a…

This chapter presents the results of a study on interlanguage variation. The production of four L2 learners of Italian, tested four times at yearly intervals while engaged in four oral tasks, is compared to that of two native speakers, and analysed with quantitative CAF measures. Thus, time, task type, nativeness, as well as group vs. individual…

This dissertation investigates the relation between prosodic events at the phrasal level and component events at the rhythmic level. The overarching hypothesis is that the interaction among component rhythmic events gives rise to prosodic patterns at the phrasal level, while at the same time being constrained by the latter, and that in the case of…

When responses function to produce the same reinforcer, a response class exists. Researchers have examined response classes in applied settings; however, the challenges associated with conducting applied research on response class development have recently necessitated the development of an analogue response class model. To date, little research…

Rural versus urban rates of suicide in current patients of a large area mental health service in Australia were compared. Suicide deaths were identified from compulsory root cause analyses of deaths, 2003-2007. Age-standardized rates of suicide were calculated for rural versus urban mental health service and compared using variance of…