Escape and avoidance learning in the earthworm Eisenia hortensis.
Interest in instrumental learning in earthworms dates back to 1912 when Yerkes concluded that they can learn a spatial discrimination in a T-maze. Rosenkoetter and Boice determined in the 1970s that the "learning" that Yerkes observed was probably chemotaxis and not learning at all. We examined a different form of instrumental learning: the ability to learn both to escape and to avoid an aversive stimulus. Freely moving "master" worms could turn off an aversive white light by increasing their movement; the behavior of yoked controls had no effect on the light. We demonstrate that in as few as 12 trials the behavior of the master worms comes under the control of this contingency.
Department of Psychological Science & Neuroscience Program , Albion College , Albion, MI , USA.
W Jeffrey
WJ
Wilson
Department of Psychological Science & Neuroscience Program , Albion College , Albion, MI , USA.
Nicole C
NC
Ferrara
Department of Psychological Science & Neuroscience Program , Albion College , Albion, MI , USA.
Amanda L
AL
Blaker
Department of Psychological Science & Neuroscience Program , Albion College , Albion, MI , USA.
Charisa E
CE
Giddings
Avoidance; Conditioning; Earthworm; Escape; Invertebrate behavior; Learning