The mid- to late-1950s period centralized arousal and bodily states as central regulators of cognitive processing and behavior. Researchers explored how affective states bias attention toward task-relevant cues, reorganize action plans, and shape performance, integrating physiological, expressive, and cognitive perspectives into a cohesive picture of regulation. Methodologically, the era favored descriptive theories, systematic observations of affective signaling, and early experiments linking arousal to cue utilization and performance, laying groundwork for subsequent emotion-cognition integration.