Stroop interference is a composite phenomenon: Evidence from distinct developmental trajectories of its components.

Only one previous developmental study of Stroop task performance (Schiller, 1966) has controlled for differences in processing speed that exist both within and between age groups. Therefore, the question of whether the early developmental change in the magnitude of Stroop interference actually persists after controlling for processing speed needs further investigation; work that is further motivated by the possibility that any remaining differences would be caused by process(es) other than processing speed. Analysis of data from two experiments revealed that, even after controlling for processing speed using z-transformed reaction times, early developmental change persists such that the magnitude of overall Stroop interference is larger in 3rd- and 5th graders as compared to 1st graders. This pattern indicates that the magnitude of overall Stroop interference peaks after 2 or 3 years of reading practice (Schadler & Thissen, 1981). Furthermore, this peak is shown to be due to distinct components of Stroop interference (resulting from specific conflicts) progressively falling into place. Experiment 2 revealed that the change in the magnitude of Stroop interference specifically results from joint contributions of task, semantic and response conflicts in 3rd- and 5th graders as compared to a sole contribution of task conflict in 1st graders. The specific developmental trajectories of different conflicts presented in the present work provide unique evidence for multiple loci of Stroop interference in the processing stream (respectively task, semantic and response conflict) as opposed to a single (i.e. response) locus predicted by historically - favored response competition accounts.

Children's Allocation of Study Time during the Solution of Raven's Progressive Matrices.

The acuity of reasoning on Raven's Progressive Matrices is strongly influenced by strategic determinants. Building on metamemory studies that highlight the influence of study-time allocation on memory development, we investigated children's allocation of study time while solving these matrices. A total of 170 children aged 6-12 years completed a computerized short-form version of the standard matrices featuring items selected to represent a broad range of difficulties. Beyond analyzing changes in mean latencies and performances with age, we used generalized additive mixed models to explore within-participant variability in response times as a function of both item complexity and overall individual efficiency. Results revealed that individual differences in performances were significantly associated with children's adaptive modulation of response times. Mediation analysis further indicated that response-time modulation contributed to age-related changes in performance. Taking account of study-time allocation in reasoning tasks may open up new avenues for the study of reasoning development and the assessment of intellectual functioning.

The development of relational integration during childhood.

Relational integration refers to the process whereby several variables are integrated within a single cognitive representation. In cognitive and developmental science, it is regarded as a central function of working memory that may contribute to the development of higher order processes, such as reasoning and fluid intelligence. In the present experiment, we administered the Relational Integration Level Assessment Task (RILAT), a novel experimental task designed to assess children's level of relational integration, to participants aged 5-12 years, along with a measure of fluid intelligence. Results yielded age norms for the development of successive levels of relational complexity and indicated a smooth progression rather than abrupt, stage-like transitions. Relational integration was found to be closely associated with fluid intelligence, as measured by Raven's Progressive Matrices. Analyses of age-related changes in this association revealed that the relationship was strongest during the stabilization periods for each level of relational complexity.

Viewing-position effects in the Stroop task: Initial fixation position modulates Stroop effects in fully colored words.

In two experiments that we conducted with adult (Experiment 1) and child (Experiment 2) participants, we experimentally controlled the eyes' first fixation in the word using a variable viewing-position technique in a classical all-letter-coloring Stroop procedure. We explored the impact of initial-fixation position (optimal viewing position [OVP] vs. end of the word) on the magnitude of Stroop effects (both interference and facilitation). The results showed that both interference and facilitation effects were reduced when the first fixation was located at the end of the word rather than at the OVP. These data make a new contribution to the study of the role of low-level processes in Stroop effects and add support to the growing body of research indicating that oculomotor processes can act as moderators of cognitive processes in the determination of Stroop effects.