Jaak Panksepp was an Estonian-American neuroscientist and psychobiologist who coined the term "affective neuroscience", the name for the field that studies the neural mechanisms of emotion. He was the Baily Endowed Chair of Animal Well-Being Science for the Department of Veterinary and Comparative Anatomy, Pharmacology, and Physiology at Washington State University's College of Veterinary Medicine, and Emeritus Professor of the Department of Psychology at Bowling Green State University. He was known in the popular press for his research on laughter in non-human animals.
Jaak Panksepp (on the right) at the promotion of honorary doctors at the University of Tartu (December 2004).
Laughter in animals other than humans describes animal behavior which resembles human laughter.
An orangutan "laughing"
Brown rats emit 50-kHz calls during rough and tumble play, and when tickled.