Learning and physiological stress: Outcomes on expression of related genes in honey bees (Apis mellifera)

Abstract

Stress is defined as any deviation form an organism's baseline physiological levels. As such, introduction of new stimuli and information, such as in learning, can be operationally defined stressors. A large body of research exists examining the role that stress plays in learning, but virtually none addresses whether or not learning itself is a measurable cause of stress. The current work seeks to explore stress in conjunction with learning to determine whether expression of three genes of interest are affected in similar or different fashions by both learning and stress. The current work employs three studies, including aversive conditioning, appetitive conditioning, and naturalistic observation to explore how expression of the candidate genes is altered under a variety of experimental contexts. Gene expression was quantified using reverse-transcriptase quantitative polymerase chain reaction. Results were analyzed using both traditional parametric statistics, and novel non-parametric statistics in Observational Oriented Modeling. Results indicate that stress and learning appear to affect all genes of interest in separate fashions, and do not appear to cause a physiological stress response as a result of learning.