Poster #33 - Optimization of cognitive control: Behavioral and electrophysiological approaches to typical development.

• In Event: 1-169 - Poster Session 04
  In Poster Session: PS 04 Section - Cognitive Processes

Integrative Statement

Cognitive control refers to the goal-directed regulation of actions. Inhibitory control is one of its core components usually assessed using conflict tasks in which a preponderant response must be suppressed in favor of the instruction-based response. Cognitive control undergoes a long and protracted development across childhood (Diamond, 2013). The size of the interference effect –differences between congruent and incongruent trials – is classically taken as the quantitative measure of control efficiency. The literature has documented the progressive reduction of congruence effects with age. However much less is known about the underlying qualitative changes. To study these changes with age, the present study focused on electromyographic (EMG) recording during performance of the Simon task and distributional analysis of its markers.

In conflict tasks, committed errors are only the tip of the iceberg: EMG recording of each muscle directly involved in response execution reveals that, on 15-20% of correct trials, a sub-threshold burst of activity can be recorded on the muscle involved in the incorrect response. Such “partial-errors”, more numerous on incompatible trials, are of interest since they result from activation of incorrect response that was subsequently suppressed. Such “partial errors” have almost never been studied in children. Only van de Laar et al. (2012) have reported such activities in children and their rate decreased as age increased.

Dynamics of processes were examined using distribution analyses. Computing the probability of a correct response as a function of response latencies, conditional accuracy functions (CAFs) allow differentiating the time course of the automatic capture of the incorrect response and its subsequent suppression from the time course of the correct, instruction-based response. In addition, plotting the difference in RT between incongruent and congruent trials, as a function of response speed (so-called “delta-plots”) reveals the dynamics of the chronometric interference effect. In the Simon task, while the size of the RT difference is large for fast responses, it largely decreases for slow responses, which has been interpreted as indexing the strength of irrelevant dimension suppression (Ridderinkhof, 2002).

In the study participated 123 children and 15 adults. They performed a child-adapted Simon task. The recording of EMG allowed the fractionation of reaction times into premotor (from stimulus to the onset of correct EMG burst) and motor time (from onset of EMG burst to overt response)

The EMG analysis revealed that the duration of premotor and motor time decreased with age, unlike number of errors that was constant across age groups. A congruency effect on premotor time, present in all age groups, decreased with age. No congruence effect on motor time was observed. CAF revealed no age differences in automatic capture of the incorrect response. However, “delta-plots” revealed that the suppression of irrelevant dimension, moderate in small children, resembles suppression of adults in children from 9 years old already.

Altogether, the present findings in the Simon task suggest that the susceptibility to incorrect response activation does not change with age, contrary to inhibitory control of irrelevant dimension which develops gradually and is functional already in 9 years old children.

Authors

• Kamila Smigasiewicz, CNRS, Aix-Marseille Université
  Non-Presenting Author

• Solène Ambrosi, CNRS, Aix-Marseille Université
  Non-Presenting Author

• Boris Burle, CNRS, Aix-Marseille Université
  Non-Presenting Author

• Agnes Blaye, Aix-Marseille University & CNRS
  Presenting Author