Children with borderline intellectual functioning (BIF; IQ 70-84) frequently present with symptoms that are similar to those observed in attention deficit hyperactivity disorder (ADHD), which complicates the clinical diagnostic process. This is particularly the case with deficits in inhibitory control, i.e. the ability to suppress irrelevant impulses or cognitions. In order to facilitate an adequate clinical diagnosis and, in the long term, the implementation of individualised treatment for affected individuals, the project aims to investigate the similarities and differences in the neurophysiological processes underlying inhibitory control in BIF and ADHD. To this end, four distinct groups are being studied: participants with I) BIF II) ADHD III) BIF+ADHD and IV) healthy control subjects.