Trailmaking

Trailmaking refers to a set of cognitive tasks designed to assess visual scanning, processing speed, and the ability to connect sequential information. These tasks are often used in neuropsychological evaluations to measure executive functions, particularly planning and cognitive flexibility. The most common form is the Trail Making Test (TMT), which typically consists of two parts, A and B.

In Part A, participants are asked to connect a series of numbered circles (1, 2, 3, etc.) in the correct numerical order as quickly as possible. This part primarily assesses visual attention and the speed of visual scanning.

Part B requires participants to connect alternating numbers and letters in sequence (1, A, 2, B, 3, C, and so on). This more complex task measures cognitive flexibility, the ability to shift between different sets of rules, and working memory in addition to visual scanning and processing speed. The time taken to complete both parts, and often the difference between Part B and Part A, are key metrics. Higher scores (longer completion times) can indicate deficits in these cognitive areas.

Trailmaking tasks are sensitive to various neurological conditions, including traumatic brain injury, stroke, dementia, and attention-deficit/hyperactivity disorder (ADHD). They are a valuable tool for screening, diagnosis, and monitoring recovery or disease progression. The simplicity of the tasks makes them easy to administer, but their interpretation requires expertise in neuropsychological assessment.