Trail Making Test: Training for cognitive flexibility

The Trail Making Test (TMT) is one of the most well-known neuropsychological tasks worldwide. It was developed in 1944 by the US Army and has established itself for decades as a standard for measuring visual attention, processing speed, and cognitive flexibility. Today, it is used in clinical diagnostics, sports psychology, and increasingly in modern brain training apps. The principle is simple: In the first variant (Part A), you connect numbered dots in ascending order — from 1 to 2 to 3 and so on. In the second, more challenging variant (Part B), you switch between numbers and letters — from 1 to A, from A to 2, from 2 to B, and so on. What sounds so simple challenges the brain on multiple levels simultaneously. This article explains what the Trail Making Test measures, why it is so widely used in research, what your performance can reveal about your cognitive health, and how you can incorporate Trail-Making-like exercises into your daily training with the SynapseGym app.

What exactly does the Trail Making Test measure?

The Trail Making Test appears at first glance as a simple connection task — but in reality, it measures a complex bundle of cognitive functions that constantly work together in everyday life. Part A primarily measures visual search, processing speed, and simple attention. You need to find the numbers on the screen and connect them in the correct order, ideally as quickly as possible. It depends on how efficiently your eyes and brain can scan a visual field. Part B adds a crucial component: cognitive flexibility. You not only have to keep track of numbers and letters simultaneously but also constantly switch between two sequences. This "set-switching" mechanism strongly activates the prefrontal cortex — the region responsible for executive functions such as planning, self-control, and task switching. The difference between Part A and Part B (TMT-B time minus TMT-A time) is considered a particularly meaningful measure. It isolates the purely executive component and is an important indicator in the diagnosis of cognitive impairments. A significantly slowed performance in Part B compared to Part A may indicate problems with mental flexibility or working memory. In clinical practice, the Trail Making Test is used to detect early cognitive changes, in the context of dementia diagnosis and after strokes. In sports, it is part of modern concussion protocols. In research, it serves as an objective measure of the effectiveness of cognitive interventions — from medications to brain training programs.

The science behind the TMT

Since the original development in the 1940s, the Trail Making Test has been used in thousands of scientific studies. Imaging examinations with functional MRI show that especially the dorsolateral prefrontal cortex, the inferior parietal cortex, and parts of the cingulum are activated. These are exactly the brain regions responsible for attention shifting, working memory, and cognitive control. An important insight from research: TMT performance changes measurably with age. The average processing time for Part A increases from about 25 seconds in young adults to 40-50 seconds in people over 70. For Part B, the increase is even more pronounced — from about 50 seconds to 100+ seconds. This age-related change is normal and not necessarily pathological. Studies like the ACTIVE study have shown that structured cognitive training can also improve TMT performance in older adults. A 2018 meta-analysis documented significant effects of computer-based brain training on tests measuring processing speed and cognitive flexibility — both components of the TMT. The connection with everyday functions is also interesting. Studies show that TMT-B performance correlates with driving ability, professional performance, and independence in old age. Therefore, the test is not just an abstract laboratory instrument, but provides clues about functions that matter in real life. In modern research, the TMT is also used to measure the effects of sleep deprivation, stress, or physical activity on cognitive performance. Even a poor night’s sleep can significantly slow down the TMT-B time.

Trail-Making-like exercises in the SynapseGym app

SynapseGym integrates the Trail-Making principle into several exercise formats that you can train daily. The app does not focus on the exact reproduction of the clinical test — which has its place in diagnostics — but on targeted training of the underlying cognitive functions: visual search, processing speed, and cognitive flexibility. Specifically, in the concentration exercises category, you will find tasks that follow the TMT principle. You connect numbers, switch between sequences, or need to coordinate parallel rows. The exercises start simple and become adaptively more difficult as you improve. The adaptive system measures your reaction time, error rate, and consistency, and automatically adjusts the difficulty. Unlike a static test, you receive immediate feedback in SynapseGym. You see how your reaction time develops over the weeks, in which areas you improve, and where there is still training potential. The integrated Cognitive Profile shows how your performance in processing speed and cognitive flexibility changes over time. A recommended training routine: three to five minutes per day with Trail-Making-like exercises, combined with other concentration and reaction tasks. Consistency beats intensity — a 2017 study showed that just 15 minutes of daily cognitive training over 12 weeks has measurable effects on processing speed. Important: SynapseGym is not a medical diagnostic tool and does not replace a professional neuropsychological examination. If you suspect cognitive impairments, please consult a neurologist or neuropsychologist. As a training and wellness tool for healthy adults, SynapseGym is scientifically well-founded.

Practical tips for better trail making

Anyone who wants to improve their TMT-like performance can apply several strategies simultaneously. First: daily training. As with physical fitness, consistency is more important than intensity. Five minutes per day are more sustainable than a weekly 30-minute session. Consolidation of new cognitive connections occurs mainly during breaks between training phases — especially during sleep. Second: optimize sleep. Even a poor night can measurably reduce cognitive processing speed. Those who regularly get seven to nine hours of quality sleep have a significantly better foundation for trail-making performance. The consolidation of newly learned cognitive strategies takes place in specific sleep phases. Third: physical activity. Aerobic activities like walking, jogging, or cycling demonstrably increase cognitive processing speed. A 2020 study showed that adults who were moderately active for at least 150 minutes per week achieved significantly better TMT scores than sedentary comparison groups. Fourth: variation. Don't just train one task, but switch between different cognitive demands. SynapseGym intentionally offers a broad mix of concentration, reaction time, memory, and bilateral exercises to maximize transfer between functions. Fifth: reduce distractions. Train in a quiet environment without smartphone notifications or background conversations. The quality of your training is more important than quantity. A focused three-minute session yields more than a distracted ten-minute session. Combining these five factors creates the optimal foundation to improve your cognitive processing speed and mental flexibility in the long term — not only in the trail making test but in all daily demands.