Little empirical evidence exists as to how materials used in art therapy affect the brain and its neurobiological functioning. This pre/post within-groups study utilized the quantitative electroencephalogram (qEEG) to measure residual effects in the brain after 20 minutes of drawing. EEG recordings were conducted before and after participants (N = 10; 6 artists and 4 non-artists) created a drawing in oil pastels. Results showed a statistical difference (p < 0.05) pre- and post-drawing among artists in the left posterior temporal, parietal, and occipital regions within the alpha frequency band. For the non-artists, differences in alpha were recorded in the right parietal and right prefrontal areas. There were no significant findings between the groups. Results suggest that alpha rhythm may play an important role in drawing. Because alpha rhythm is associated with self-regulation, relaxation, memory, visual processing, intelligence, and creativity, this finding has useful implications for art therapy. The application of qEEG methodology with art therapy may help assess and further refine clinical treatment.