A study investigated whether selective attention to a particular television modality resulted in different levels of attention to and memory for each modality. Two independent variables manipulated selective attention. These were the semantic channel (audio or video) and viewers' instructed focus (audio or video). These variables were fully crossed in a within-subjects experimental design. Attention levels were investigated by measuring reaction times to cues in each modality (audio tones and color flashes). Memory questions asked about channel-specific contents. Both selective attention manipulations affected intensive measures of attention similarly. Because of this similarity, the modalities appear to tap a common pool of resources. Memory measures showed a modality-specific effect. Visual information was remembered whether or not that information was important semantically, and whether or not subjects were instructed to focus on that channel. Auditory information, however, was better remembered when viewers were focused on the audio channel. Auditory information and auditory-based messages appear to demand greater resources than visual information and visual-based messages. Further research in this field can lead to a better understanding of the processing of not only television material, but also real-world multi-channel sources of information. (Seven figures are included; three appendixes--description of stimuli, order of tapes, and a sample questionnaire-- and 181 references are attached.) (Author/SR)