BACKGROUND: A growing body of evidence suggests a link between cognitive and pathological changes in amyotrophic lateral sclerosis (ALS) and in frontotemporal lobar dementia (FTLD). Cognitive deficits have been investigated much less extensively in primary lateral sclerosis (PLS) than in ALS. OBJECTIVE: to investigate bioelectrical activity to Stroop test. assessing frontal function. https://www.drcristinosuarez.com/