Affective state and visual decision-making in bumblebees

Abstract

Affective states, or emotions, are internal states of an organism, brought about by an appraisal of the environment, which result in specific physiological, cognitive, and behavioural responses. These states can significantly influence information processing and alter cognition and perception. Recent research has argued for similar emotion- like states in bees, using judgment bias tests, a widely accepted method for measuring emotional states in mammals. Although these findings suggest the possibility of emotion-like states in bees, alternative explanations have been suggested for these results. There is also little knowledge of how these states influence other cognitive and sensory responses. In this thesis, I develop robust tests for these states in bees and investigate their effect on multiple visual responses. In the first experimental chapter, I develop a novel test for pessimistic cognitive biases in bees that controls for alternative interpretations and provides stronger evidence of the presence of emotion-like states in bees. Having established the presence of these states, subsequent experimental chapters delve into their impact on information processing during different stages of decision-making. In the second experimental chapter, I examine how negative emotional states affect visual acuity, revealing that such states may facilitate the ability to resolve fine spatial details, potentially aiding in threat detection. The third experimental chapter explores how negative states influence behavioural flexibility. I demonstrate that experiencing negative states facilitates the ability to estimate and update expectations of reward value, consequently enabling flexible responses to environmental change. The last experimental chapter explores methods to investigate the neural structures linked to emotion-like states and visual learning in bees for future research. Collectively, these experiments provide strong support for the existence of emotion-like states in bees and suggest that these states may serve as adaptive mechanisms to enhance survival.