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THREAD about our new paper 'Neural dynamics underlying coherent motion perception in children and adults' in Developmental Cognitive Neuroscience sciencedirect.com/science/articl…
We looked at age-related changes in motion evoked potentials to help us understand why motion processing abilities develop so slowly through childhood
Previous studies with children have generally looked at responses to the onset of a moving stimulus, so don't necessarily tell us about direction-specific processing (instead it could be about luminance modulations)
So in our task, we first presented some random motion (to get any luminance/motion onset potentials out the way), before introducing a coherent motion stimulus (w/ varying strengths). Participants judged the direction of coherent motion (up/down) as quickly & accurately as poss 
102 kids aged 6 to 12 years and 20 adults took part with high-density EEG nets on their heads
We used an analysis technique called Reliable Components Analysis which is a data-driven way of finding components that are reliable from trial-to-trial. It's nice as you don't have to select timepoints/electrodes like in traditional ERP analyses
Yet we found two components that mapped on remarkably well to previously reported ERP components
The most reliable component (Component 1) resembled the centro-parietal positivity (CPP) in both its topography & in its slow ramping timecourse. It predicted response time even when the coherence was kept constant - reflecting decision-specific activity
The second most reliable component (Component 2) looked like the coherence-onset evoked potential in adults. It had an earlier onset than the Component 1 and was a more transient potential. We think this component reflects early, sensory processing
Both of these components showed clear age-related differences. We conclude that the protracted development of motion processing abilities is accompanied by maturation in both early sensory and later decision-related processes
Next steps include modelling the decision-making process, and also comparing the activity with that of autistic children and dyslexic children to inform on the specificity of motion processing differences in different conditions
This project arose from an @ExpPsychSoc Study Visit grant to Stanford University, and then was supported by an EPS Small Grant and the @wellcometrust. Thank you to these wonderful funders and all the participants. END OF THREAD
