TY - JOUR
T1 - Does conditioned taste aversion learning in the pond snail Lymnaea stagnalis produce conditioned fear?
AU - Kita, Serina
AU - Hashiba, Ryuji
AU - Ueki, Saya
AU - Kimoto, Yukari
AU - Abe, Yoshito
AU - Gotoda, Yuta
AU - Suzuki, Ryoko
AU - Uraki, Eriko
AU - Nara, Naohisa
AU - Kanazawa, Akira
AU - Hatakeyama, Dai
AU - Kawai, Ryo
AU - Fujito, Yutaka
AU - Lukowiak, Ken
AU - Ito, Etsuro
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 2011/2
Y1 - 2011/2
N2 - In conditioned taste aversion (CTA) training performed on the pond snail Lymnaea stagnalis, a stimulus (the conditional stimulus, CS; e.g., sucrose) that elicits a feeding response is paired with an aversive stimulus (the unconditional stimulus, US) that elicits the whole-body withdrawal response and inhibits feeding. After CTA training and memory formation, the CS no longer elicits feeding. We hypothesize that one reason for this result is that after CTA training the CS now elicits a fear response. Consistent with this hypothesis, we predict the CS will cause (1) the heart to skip a beat and (2) a significant change in the heart rate. Such changes are seen in mammalian preparations exposed to fearful stimuli. We found that in snails exhibiting long-term memory for one-trial CTA (i.e., good learners) the CS significantly increased the probability of a skipped heartbeat, but did not significantly change the heart rate. The probability of a skipped heartbeat was unaltered in control snails given backward conditioning (US followed by CS) or in snails that did not acquire associative learning (i.e., poor learners) after the one-trial CTA training. These results suggest that as a consequence of acquiring CTA, the CS evokes conditioned fear in the conditioned snails, as evidenced by a change in the nervous system control of cardiac activity.
AB - In conditioned taste aversion (CTA) training performed on the pond snail Lymnaea stagnalis, a stimulus (the conditional stimulus, CS; e.g., sucrose) that elicits a feeding response is paired with an aversive stimulus (the unconditional stimulus, US) that elicits the whole-body withdrawal response and inhibits feeding. After CTA training and memory formation, the CS no longer elicits feeding. We hypothesize that one reason for this result is that after CTA training the CS now elicits a fear response. Consistent with this hypothesis, we predict the CS will cause (1) the heart to skip a beat and (2) a significant change in the heart rate. Such changes are seen in mammalian preparations exposed to fearful stimuli. We found that in snails exhibiting long-term memory for one-trial CTA (i.e., good learners) the CS significantly increased the probability of a skipped heartbeat, but did not significantly change the heart rate. The probability of a skipped heartbeat was unaltered in control snails given backward conditioning (US followed by CS) or in snails that did not acquire associative learning (i.e., poor learners) after the one-trial CTA training. These results suggest that as a consequence of acquiring CTA, the CS evokes conditioned fear in the conditioned snails, as evidenced by a change in the nervous system control of cardiac activity.
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U2 - 10.1086/BBLv220n1p71
DO - 10.1086/BBLv220n1p71
M3 - Article
C2 - 21385959
AN - SCOPUS:79953664942
VL - 220
SP - 71
EP - 81
JO - Biological Bulletin
JF - Biological Bulletin
SN - 0006-3185
IS - 1
ER -