The Neuroscience of Handwriting：Applications for Forensic Document Examination

At a time when the validity and reliability of document examination is being closely scrutinized, Caligiuri (psychiatry, U. of California San Diego) and Mohammed, a forensic document examiner, explore the neuroscientific principles of normal and pathological hand motor control and handwriting for forensic documentation examination and legal professionals and researchers and discuss relevant theory and practice with examples from recent studies. They provide background on the fundamentals of motor control, with reference to handwriting; the fundamental principles of neuroanatomy and neurochemistry of hand motor control; theories of motor control and their application to handwriting research; common neurodegenerative diseases and their epidemiology, pathophysiology, and motor characteristics; common psychotropic medications for depression, bipolar disorder, and psychosis, their mechanisms of action, and why they are important in understanding motor behavior and handwriting; and the effects of the aging process on motor control and handwriting. The second section covers advances in the quantitative approach to signature authentication, mainly the kinematic approach to genuine, disguised, and forged signatures, and presents data from the authors' studies that tested specific hypotheses about whether a signature is authentic or forged, followed by a final section outlining their studies on the effects of medication and disease on handwriting, including progressive supranuclear palsy, neurological diseases, psychotropic medications, and substance abuse. Annotation Ac2012 Book News, Inc., Portland, OR (booknews.com)

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.