This study assessed the effect of emotional factors on Trail Making Test Part B performance for a sample of 105 neuropsychological referrals for whom there was no neurodiagnostic evidence of brain damage. Trails B scores declined in relation to elevated MMPI scores on Scales 6, 7, and 8, though only nine patients performed within the impaired range. The results suggest that (a) Trails B performance is resilient to a variety of emotional influences, (b) psychotic symptoms and severe anxiety impede Trails B performance, though rarely to the extent caused by brain damage, and (c) the MMPI provides objective criteria that help rule out emotional effects on Trails B performance.