Graphomotor functions in ADHD – motor or planning deficit? A microgenetic approach

Attention Deficit Hyperactivity Disorder (ADHD) is the most common neurobehavioural disorder of childhood. Although graphomotor deficits are not listed as a diagnostic criterion for ADHD, they are very common. It remains unclear, however, whether this is caused by motor deficits or by problems in planning and organizing behavior. The experimental group consisted of 30 boys with ADHD. The control group consisted of 30 boys with no deficits, matched in terms of age and IQ. The Clock Drawing Test (CDT), and the Rey-Osterrieth Complex Figure Test were used to analyze graphomotor and planning functions. As expected, the ADHD children achieved significantly lower scores on the Rey-Osterrieth Figure for both speed and accuracy, in both the copying and reproduction tasks.The ADHD children showed less complexity, along with a tendency to dislocate, rotate, or omit elements of the model. On the Clock Drawing Test, the ADHD children significantly more often drew the clock face incorrectly, and even when they did not, they more often indicated the wrong time. The strongest correlation was between the results on the Rey-Osterrieth Test and precision in drawing the clock face, both of which tasks are heavily dependent on graphomotor functions. Children with ADHD exhibit diverse deficits of cognitive and behavioral processes, including graphomotor deficits. The latter seem to be associated with both disturbances of coordination and fine motor control resulting from hyperactivity and difficulties in the planning of writing, caused by executive dysfunction.