Poster Session F, Tuesday, March 26, 8:00 – 10:00 am, Pacific Concourse
A better understanding of impulsivity in children with Attention Deficit Hyperactivity Disorder : an electromyographic approach
Aurélie Grandjean1,2, Isabel Suarez4, Elisa Diaz4, Laure Spieser1,2, Boris Burle1,2, Agnès Blaye1,3, Laurence Casini1,2; 1Aix-Marseille Université, 2Laboratoire de Neurosciences Cognitives, 3Laboratoire de Psychologie Cognitives, 4Universidad del Norte de Barranquilla
Attention deficit/hyperactivity disorder (ADHD) is considered to be one of the most common developmental disorders diagnosed in childhood. It is characterized by symptoms of inattention, hyperactivity and impulsivity. Impulsivity refers both to the susceptibility to activate inappropriate automatic responses and to a deficit in the ability to inhibit them. Whether these two aspects are involved in ADHD remains to be deciphered. In this aim, we used a novel approach based on behavioral analyses extended with Electromyographic activity recording to decipher the effects of ADHD on the expression and suppression of erroneous automatic actions. We compared performance of 24 children with ADHD and 24 typically developing children when performing a Simon reaction time task, which is well-known to elicit automatic response tendencies. Electromyographic activity was recorded from the flexor pollicis brevis of each thumb. The behavioral results have shown that children with ADHD were slower and presented a larger interference effect compared with control children suggesting that children with ADHD present difficulties in interference control. Moreover, the preliminary Electromyographic data analysis has revealed two main effects: 1/ the incorrect activation rate, measuring the strength of the susceptibility to trigger automatic responses, was similar in both groups, 2/ the correction rate, measuring the ability to suppress automatic actions was lower in children with ADHD, suggesting a deficit in inhibition of automatic actions. In conclusion, our data suggest that the difficulties in the interference control would be due to a deficit in inhibiting automatic responses rather to a larger susceptibility to activate them.
Topic Area: EXECUTIVE PROCESSES: Monitoring & inhibitory control