Reaction time and cognitive-linguistic performance in adults with mild traumatic brain injury.

The sample was small, with 20 adults with mild traumatic brain injury and 21 adults with orthopedic injuries. The authors' post-hoc power analysis said 96 to 456 participants would be needed to detect the observed small differences at 80% power. Participants were not selected for ongoing symptoms; many had no loss of consciousness, were discharged home, and most had resumed work or school, so this was a very mild group. The comparison group also had trauma and was tested in the same recovery window, which may reduce differences but also makes it hard to attribute any small differences to brain injury alone. The category-naming task has limited everyday validity, and scoring relied on older norms that may label modern responses as errors. Volunteers may have been people with flexible schedules and fewer symptoms, and participants were paid, which can bias who enrolls. Time post-injury differed marginally between groups, and correlations with time post-injury suggest this could affect performance.

The paper is tagged as supported by NIH extramural research funding. No author conflict-of-interest declaration appears in the supplied text.

Do not conclude that mild traumatic brain injury does not affect naming. The study was small, enrolled people with very mild injuries who had mostly recovered, and the accuracy difference was not clear, so it cannot rule out subtle effects.