This study directly tests the hypothesis that secondary task reaction time (STRTs) measured during television viewing index available resources rather than resources allocated by the viewer, resources required by the message, or resources remaining in the system. An initial test of the hypothesis did not support the theoretical interpretation of STRTs as either available or remaining resources. A subsequent secondary analysis introduced a new measure of television message complexity called information introduced. The stimuli were recoded using this measure and reanalyzed to test the same hypothesis. Results of the secondary analysis yielded a pattern of STRT responses supporting the prediction that STRTs are indexing available resources,.