1. Neuroanatomical and neurochemical bases of motor control -- 2. Neuroanatomical basis of handwriting movements -- 3. Models of handwriting motor control -- 4. Neurological disease and motor control -- 5. Psychotropic medications : effects on motor control -- 6. Aging and motor control -- 7. A kinematic approach to signature authentication -- 8. Isochrony in genuine, autosimulated, and forged signatures -- 9. Kinematic analyses of stroke direction in genuine and forged signatures -- 10. Neurological disease and handwriting -- 11. Effects of psychotropic medication on handwriting -- 12. Substance abuse and handwriting -- 13. Aging and handwriting -- 14. Conclusions.