Journal of the International Neuropsychological Society

Research Articles

Construct validity of the Trail Making Test: Role of task-switching, working memory, inhibition/interference control, and visuomotor abilities


a1 Brain Damage Service Network, Hospital Aita Menni, Bilbao, Spain

a2 Department of Basic Psychology II, Universidad Complutense de Madrid, Madrid, Spain

a3 Alzheimer’s Disease Research Unit, CIEN Foundation-Reina Sofia Foundation, Madrid, Spain

a4 Clinical Neuropsychology Research Group, Institut Universitari d’Investigació en Ciències de la Salut (IUNICS), Department of Psychology, University of the Balearic Islands, Spain

a5 Department of Psychiatry, Hospital Universitario Marques de Valdecilla, Santander, Spain

a6 Department of Basic Psychology II, UNED, Madrid, Spain

a7 Brain Damage Service Network, Hosp. Beata Maria Ana, Madrid, Spain

a8 Psychology Service, Clinica Ubarmin, Pamplona, Spain


The aim of this study was to clarify which cognitive mechanisms underlie Trail Making Test (TMT) direct and derived scores. A comprehensive review of the literature on the topic was carried out to clarify which cognitive factors had been related to TMT performance. Following the review, we explored the relative contribution from working memory, inhibition/interference control, task-switching ability, and visuomotor speed to TMT performance. Forty-one healthy old subjects participated in the study and performed a battery of neuropsychological tests including the TMT, the Digit Symbol subtest [Wechsler Adult Intelligence Scale (Third Version) (WAIS-III)], a Finger Tapping Test, the Digits Forward and Backward subtests (WAIS-III), Stroop Test, and a task-switching paradigm inspired in the Wisconsin Card Sorting Test. Correlation and regression analyses were used in order to clarify the joint and unique contributions from different cognitive factors to the prediction of TMT scores. The results suggest that TMT-A requires mainly visuoperceptual abilities, TMT-B reflects primarily working memory and secondarily task-switching ability, while B-A minimizes visuoperceptual and working memory demands, providing a relatively pure indicator of executive control abilities. (JINS, 2009, 15, 438–450.)

(Received July 27 2008)

(Reviewed February 06 2009)

(Accepted February 13 2009)


c1 Correspondence and reprint requests to: José A. Periáñez, Department of Basic Psychology II, Universidad Complutense de Madrid, Campus de Somosaguas, 28223 Madrid, Spain. E-mail: