Connect items in order: 1→2→3 (Trail A) or 1→A→2→B (Trail B). Clinical staple of speed and flexibility.
Trail Making was originally part of the Army Individual Test Battery (1944) and is one of the most-used clinical neuropsychology tasks.
Part A measures pure visual scan speed. Part B (alternating numbers and letters) adds set-shifting and working memory.
It's sensitive to frontal-lobe damage, ageing, ADHD, and concussion.
We track time, errors, and adjusted time (errors penalized).
Reitan (1958) standardized norms still used today. Trail B/A ratio indexes executive function specifically.
Performance correlates with the dorsolateral prefrontal cortex and white-matter integrity.
Visual search speed, sequencing, and on Trail B the flexibility to switch between two ordered series.
This task gauges how quickly your eyes scan a cluttered field, hold a sequence in mind, and guide the connecting line to the next target. A fast, error-free Trail A reflects efficient visual search and graphomotor speed: you locate the next number almost reflexively rather than re-scanning the whole array each step.
Trail B layers in alternation between numbers and letters, taxing working memory and set-shifting; the gap between your A and B times isolates that switching cost. Unlike a pure reaction task, performance leans heavily on organised scanning, which is why poor Trail B is a sensitive everyday marker of distractibility and divided-attention difficulty.
Master ordered scanning on Trail A before adding the switching load of Trail B.
Start on Trail A with a small set and aim for a clean, continuous line, not bursts of speed. Once your times plateau and errors approach zero, move to Trail B and to larger arrays. Focus on anticipating the next target while your hand finishes the current connection, so search and movement overlap rather than alternate.
The classic mistake on Trail B is losing your place in one series while hunting the other: you find the next number but forget which letter came last. Sub-vocalise the pair you are tracking (three, C, four, D) to keep both threads live. Slow down at switch points; that is where errors and backtracking cost the most time.
Completion time is the headline; the B-minus-A difference is the more telling number.
Read your own trend rather than chasing a universal cut-off, since times depend on array size, input device, and screen. A shrinking Trail A time signals faster search and sequencing. Watch the gap between your B and A times: when that difference narrows, your set-shifting and working memory are carrying the alternation more smoothly, independent of raw speed.
Scores swing with fatigue, caffeine, sleep, and using a mouse versus a touchscreen, so compare like sessions and look at multi-week averages. A strong time does not certify executive function clinically, nor does it speak to memory, reasoning, or vocabulary. It is one narrow window on processing speed and flexibility, not a verdict on overall ability.