Final answer:
Mary Cover Jones published 'A laboratory study of fear: The case of Peter,' aiming to uncondition an established fear of rabbits in a child, referencing John B. Watson's Little Albert experiment where fear responses were conditioned.
Step-by-step explanation:
The person who published 'A laboratory study of fear: The case of Peter,' in which fear reaction in a child was reconditioned, was Mary Cover Jones.
The study aimed to uncondition an established fear of rabbits in a child named Peter, thereby essentially reversing a conditioned fear response.
This research by Jones is often considered a continuation of the work initiated by John B. Watson, famously known for the Little Albert experiment, where conditioned emotional responses were demonstrated.
In Watson's experiment, the Unconditioned Stimulus (UCS) was the loud noise, the Conditioned Stimulus (CS) was the white rat, the Unconditioned Response (UCR) was the fear caused by the loud noise, and the Conditioned Response (CR) was the fear response to the white rat caused by its association with the loud noise.
Watson and his colleagues' work deeply impacted our understanding of classical conditioning and the development of fears and phobias.