Multiple Resource Theory

A cognitive psychology theory proposed by Christopher Wickens that explains how humans allocate attention across concurrent tasks. The theory posits that humans have separate pools of cognitive resources for different modalities (visual vs. auditory), processing stages (perception vs. response), and codes (spatial vs. verbal). People can divide attention more effectively between tasks that use different resource pools (e.g., visual and auditory) than between tasks competing for the same pool (e.g., two auditory tasks). In accessibility research, this theory helps explain why blind screen reader users struggle with concurrent think-aloud protocols — both listening to the screen reader and producing speech compete for the same auditory-verbal resources.