Studies from recent years have shown that there are unique and distinctive differences between the handwriting of patients with Parkinson's disease and that of healthy people. (Agencies)
However, most studies that have focused on handwriting to date focused on motor skills (such as the drawing of spirals) and not on writing that involves cognitive abilities, such as signing a cheque, copying addresses, etc.
According to Professor Sara Rosenblum, of the University of Haifa's Department of Occupational Therapy, who initiated the study, Parkinson's patients report feeling a change in their cognitive abilities before detecting a change in their motor abilities.
Therefore, a test of cognitive impairment could attest to the presence of the disease and offer a way to diagnose it earlier. The new joint study by researchers at the University of Haifa and Rambam Hospital in Israel compared the handwriting of 40 sick and healthy subjects.
In the study, the researchers asked the subjects to write their names and gave them addresses to copy, two everyday tasks that require cognitive abilities.
Participants were 40 adults with at least 12 years of schooling, half healthy and half known to be in the early stages of Parkinson's disease (before obvious motor signs are visible).
The writing was done on a regular piece of paper that was placed on electronic tablet, using a special pen with pressure-sensitive sensors operated by the pen when it hit the writing surface.
A computerized analysis of the results compared a number of parameters: writing form (length, width and height of the letters), time required, and the pressure exerted on the surface while performing the assignment.
Analysis of the results showed differences between the patients and the healthy group, and all subjects, except one, had their status correctly diagnosed (97.5 percent accuracy).
The Parkinson's disease patients wrote smaller letters, exerted less pressure on the writing surface, and took more time to complete the task.
According to Rosenblum, a particularly noticeable difference was the length of time the pen was in the air between the writing of each letter and each word. "This finding is particularly important because while the patient holds the pen in the air, his mind is planning his next action in the writing process, and the need for more time reflects the subject's reduced cognitive ability," Rosenblum said.
"Changes in handwriting can occur years before a clinical diagnosis and therefore can be an early signal of the approaching disease," Rosenblum added.
Studies from recent years have shown that there are unique and distinctive differences between the handwriting of patients with Parkinson's disease and that of healthy people.