[Methylphenidate and short-term memory in young females with attention deficit hyperactivity disorder. A study using functional magnetic resonance imaging].

INTRODUCTION: Attention deficit/hyperactivity disorder (ADHD) is a common behavioral disorder found mainly in males, thus current knowledge on its clinical expression in female adults is extremely limited. AIM. To evaluate the behavioral and neural substrates associated with the performance of a short-term memory task in female ADHD adults, with and without methylphenidate exposure, with respect to a control group.

SUBJECTS AND METHODS: Two groups of eight young right-handed, female, university students with ADHD and healthy controls matched by age, gender, handedness and academic level, voluntarily participated. All subjects performed twice an easy auditory short-term memory task (ADHD group without, and 90 minutes post-intake of methylphenidate 0.4 mg/kg in a counterbalanced order). The BOLD-fMRI response was used as a measure of neural activity during task performance.

RESULTS: ADHD subjects showed a tendency to improve their performances under medication, showing an increased widespread functional activation, especially relevant over left frontal and cerebellar areas, in comparison with control subjects.

CONCLUSIONS: Methylphenidate slightly improves short-term memory task performance in adult female ADHD subjects by modifying underlying neural functioning patterns.