Effects of baclofen on oral counting, arithmetic, and symbol decoding: An explorative multiple-baseline design across subjects

Abstract

Sedation is a well-recognized side effect of the antispasticity medication baclofen. The literature discussing baclofen has shown that it is detrimental to memory and learning in individuals with known cognitive dysfunction. There is no information on how baclofen effects the function of individuals with normal baseline cognition despite frequent clinical reports of symptoms. This study explored the effect of baclofen on counting, arithmetic, and symbol decoding over a 9-week period of time on five adult males with traumatic spinal cord injury and no known cognitive dysfunction. We employed a repeated-measures, multiple baseline, double-blind, single-subject research design. The independent variable was antispasticity medication treatment, where the levels were 40 and 80 mg/day of baclofen versus placebo treatment. The dependent variables were speed and accuracy of counting integers, solving arithmetic problems, and decoding symbols. Slope and trend analysis of these data showed no change in counting and arithmetic tasks for all five subjects between each phase of the study. Changes were evident regarding ability to decode symbols, with varying trends across phases and subjects. Results of this study showed that baclofen, in low to moderate doses, did not seem to affect subjects' performance of oral counting or solving arithmetic problems. Baclofen did affect subjects' performance of symbol decoding, but with no consistent trend. These results suggest that further study of problem solving and memory funtion during baclofen administration would be useful.