Background. - The study of children's personality and its development has generated several theoretical models in psychology. In a developmental approach, Buss and Plomin elaborated a genetic model of temperament that involves four dimensions: emotionality (refers to the negative quality of the emotion and the intensity of the emotional reactions), activity (intensity and frequency of a person's energy output in motor movements and speech), sociability (search for social relationships and preference for activities with others) and shyness (behavioural inhibition and feelings of distress when in interaction with strangers). The psychobiological approach postulates a biological model of personality. Thus, in Gray's first model, there are two brain systems that explain behaviours: the Bbehavioural Activation System (BAS) related to impulsivity and the Behavioural Inhibition System (BIS) linked to anxiety. Finally, dispositional theories seek to identify functional units of the normal personality from the factorial approach. Accordingly, Barbaranelli et al. build a questionnaire, the big five questionnaire for children (BFQ-C), which is intended to estimate the emergence of five fundamental dimensions (energy/extraversion, agreeableness, conscientiousness, emotional instability and intellect/openness) in children from 8 to 18 years. The clinical study we will present concerns the personality of children suffering from attention-deficit hyperactivity disorder (ADHD). Study 1: methods and results. - In a first study, we compared the ratings of 33 children with ADHD regarding their personality, as well as the ratings of their parents, over a one-year interval. The EAS questionnaire tapping into the genetic model put forth by Buss and Plomin evaluates four dimensions: emotionality, activity, sociability and shyness. The BIS/BAS scales for children correspond to Gray's first psychobiological model of personality. The BIS scale is unidimensional and the BAS scale is divided into three subscales (drive, fun-seeking and reward responsiveness). The answers collected from parents at the two moments of completion of the EAS were comparable and the correlations were all higher than 0.70. Concerning the children, there were no significant differences between the two time periods but the correlations were rather low. On the BIS/BAS scales, they varied from 0.22 (fun-seeking BAS scale) to 0.51 (BIS scale), whereas the obtained correlations on the EAS ranged from 0.32 (emotionality) to 0.58 (activity and shyness). Finally, to compare the answers of the children with their parents on the EAS questionnaire, we used a correlation coefficient test. For time 1, the correlations varied from 0.54 (emotionality) to 0.69 (sociability), and for time 2, they varied from 0.18 (sociability) to 0.50 (shyness). The concordance between the parents' and children' answers was thus higher than in a group from the general population. Study 2: methods and results. - In the second study, we compared the personality of children with ADHD (n=35) with a sample from the general population (n=35). The two groups of subjects were matched on age (mean: 12.7 years) and made comparable for gender. Participants with ADHD were comparable with control participants on the BIS, as well as on the reward responsiveness subscale of the BAS. Furthermore, participants with ADHD and controls were comparable concerning the tendency to avoid and the anxiety. However, as expected, those with ADHD obtained higher scores on two subscales of the BAS. Concerning the traits of temperament, participants with ADHD reported being more active and having greater emotionality than did control subjects. On the other hand, there were no group differences for the two other aspects of temperament (sociability and shyness). Finally, participants with ADHD obtained higher scores on the BFQ-C than did control participants. It is interesting to note that children with ADHD obtained higher scores on the extraversion scale of the BFQ-C and the activity scale of the EAS. Our findings parallel the existing literature concerning the neuroticism scale of the BFQ-C and the BAS, but not the agreeableness and conscientiousness scales of the BFQ-C. Discussion. - It is interesting to note that children have a less stable representation of their own temperament as compared to the evaluation of their parents. This study replicates the findings of previous research on adults with ADHD regarding neuroticism (emotional instability), but contrary to findings in adults with ADHD, children obtained elevated scores on the conscientiousness and agreeableness subscales. In accordance with our hypotheses, children with ADHD could be distinguished from control participants on the BAS, particularly for the drive and reward responsiveness subscales. Furthermore, they also obtained higher scores on the extraversion subscale of the BFQ-C and the on the EAS activity subscale. (C) L'Encephale, Paris, 2012.
