Handwriting is a cognitively challenging task because it requires a combination of fine motor control and complex mental skills such as selecting, organizing, and interpreting sensory information. Because of the high demand on the brain, it is a potential marker of cognitive decline, especially with age. This often results in slow or choppy handwriting.
Now new Frontiers of human neuroscience In this study, a team of Portuguese researchers investigated whether handwriting characteristics, such as speed and stroke composition, differ between older adults who show signs of cognitive decline and those who do not, and whether handwriting characteristics could therefore serve as a diagnostic tool.
“Writing is not just a motor activity, it’s a window into the brain,” says lead author Dr. Ana Rita Matias, assistant professor at the Faculty of Sport and Health at the University of Évora. “We found that older adults with cognitive impairment showed unique patterns in the timing and organization of their handwriting movements. Over time, we found that in tasks with higher cognitive demands, cognitive decline was reflected in how efficiently and coherently their handwriting movements were organized.”
Ready, set, burn
The researchers set out to determine whether the writing process could provide an earlier and more sensitive indicator of cognitive decline than test scores or final output, measures often analyzed in traditional assessments.
The study included 58 older adults aged 62 to 92 living in care homes. Thirty-eight participants had previously been diagnosed with a type of cognitive impairment. Participants performed two types of tasks using an ink pen on a digitizing tablet. During the pen control task, participants were asked to draw 10 horizontal lines within 20 seconds and create at least 10 dots on the paper within the same time frame. The handwriting speed task involved taking notes on two sentences of varying complexity, each shown on a card or dictated.
Results showed that neither pen control task was able to distinguish cognitive states between groups. Being “simple” tasks, these rely primarily on basic motor control, which may not be sufficient to reveal the subtle differences exhibited in more cognitively demanding tasks. The copying task, which is more mentally demanding than pen control but less demanding than dictation, also showed a trend toward significance, although no group differences were shown.
However, the results of the dictation task showed clear differences between the two participant groups. This may be due to the higher cognitive demands that such tasks place on working memory and executive functions. “Dictation tasks are more sensitive because they require the brain to do multiple things at the same time: listening, processing language, converting sounds into written form, and coordinating movements,” Mathias said.
“Differences can emerge even within dictation tasks: longer, less predictable, and linguistically demanding sentences place greater strain on cognitive resources.”
Dr. Ana Rita Mathias, University of Évora
In the cognitively impaired group, two predictors were found to be significant for short sentences in the dictation task: onset time and number of strokes. For more complex sentences, three predictors were important: vertical size, onset time, and duration. This may be because not all handwriting features reflect cognition in the same way.
“Timing and stroke organization are closely related to how the brain plans and executes actions, which depend on working memory and executive control. As these cognitive systems deteriorate, writing becomes slower, more fragmented, and less coordinated,” Mathias explained. “In contrast, other features remain relatively preserved, especially in the early stages of cognitive decline, making the index less sensitive.”
daily writing
The researchers said their approach, which relies solely on simple written tasks and accessible digital tools, could serve as a practical way to monitor cognitive decline in a variety of settings, such as clinics. As it is a non-invasive and relatively low-cost method, it can be easily incorporated into routine clinical practice.
However, this approach is still an emerging methodology, and future studies should confirm long-term effects in larger and more diverse populations. Therefore, the results of the current study may not be easily transferable. Also, drug use and its possible effects were not considered.
“The long-term goal is to develop tools that are easy to administer, time-efficient, affordable, and can be integrated into everyday medical environments without the need for specialized or expensive equipment,” Matthias concluded.
