ABSTRACT

Purpose: Discourse production is a naturalistic and commonly occurring form of communication. Thus, it is no surprise that discourse formulation is a clinically relevant assessment for persons who experience communication impairments associated with cognitive disruptions such as traumatic brain injury, mild cognitive impairment, and dementia. The most commonly studied genre of discourse is the production of fictional narratives; however, little is known about the formulation of other, more commonly occurring and ecologically valid forms of discourse. To better understand the communication behaviors associated with these other discourse forms, this pilot research examined efficiency, informativeness, and neurovascular activation during formulation of procedural, personal, conversation, and fictional discourse produced by neurologically healthy adults. Methods: Ten healthy adults formulated spoken discourse in four clinically important genres. Efficiency and informativeness characteristics were analyzed, and prefrontal neurovascular activation was measured using functional near infrared spectroscopy. Results: Efficiency was similar between the four genres. Informativeness varied significantly by genre and was lowest in complex procedural discourse and highest in conversation. Differences in location and magnitude of neurovascular activation between genres were not significant. Significant negative relationships and trends between discourse efficiency and neurovascular activation were observed, suggesting a negative relationship between discourse performance and neurovascular processing demands. Conclusions: Measurement of discourse efficiency enables meaningful comparison between four genres of discourse. Therefore, the measurement and assessment of functionally relevant genres of discourse is feasible, and may be more relevant than fictional storytelling for individuals with cognitive-communication impairments.