The Neuroscience of Handwriting

Michael P. Caligiuri, PhD, is a professor in the Department of Psychiatry at the University of California, San Diego. His research over the past two decades has focused on understanding how drugs and disease affect motor control and fine hand movements. He has served as the lead scientist on several federally and industry-sponsored studies on identifying treatment response in psychiatric patients and has authored over 100 peer-reviewed articles in medical journals and book chapters on movement disorders, brain imaging, and biomedical instrument development. His current research interest focuses on kinematic studies of impaired handwriting and understanding writer-based sources of variability in signature authentication. Linton A. Mohammed, MFS, D-ABFDE, has been a forensic document examiner for 25 years. He has testified as an expert witness over 100 times in the United States, England, and the Caribbean. He is currently in private practice with Rile, Hicks, & Mohammed with offices in Long Beach, California, and San Bruno, California. He is certified by the American Board of Forensic Document Examiners and holds a Diploma in Document Examination from the Forensic Science Society in England. He is the current president of the American Society of Questioned Document Examiners, is a fellow in the Questioned Document Section of the American Academy of Forensic Sciences, and is currently completing work for a PhD in Human Biosciences at La Trobe University, Melbourne, Australia.

FUNDAMENTAL ASPECTS OF MOTOR CONTROL AND HANDWRITING. Neuroanatomical and Neurochemical Bases of Motor Control. Neuroanatomical Bases of Handwriting Movements. Models of Handwriting Motor Control. Neurological Disease and Motor Control. Psychotropic Medications: Effects on Motor Control. Aging and Motor Control. KINEMATICS OF SIGNATURE AUTHENTICATION. A Kinematic Approach to Signature Authentication. Isochrony in Genuine, Autosimulated, and Forged Signatures. Kinematic Analyses of Stroke Direction in Genuine and Forged Signatures. NEUROLOGIC DISEASE, DRUGS, AND AGING AND THEIR EFFECTS ON HANDWRITING. Neurological Disease and Handwriting. Effects of Psychotropic Medications on Handwriting. Substance Abuse and Handwriting. Aging and Handwriting. Conclusions. Bibliography.