title: An automated learning apparatus for classical conditioning of Lymnaea stagnalis.
abstract: BACKGROUND
  The pond snail Lymnaea stagnalis is capable of taste avoidance classical conditioning (TAC) with sucrose as the conditional stimulus (CS) and mechanical prodding as the unconditional stimulus (US). After successful training, feeding behavior is significantly suppressed in response to CS presentation.
  
  
  METHODS
  An automated apparatus is described for the training of multiple snails up to 10 snails at the same time. The new apparatus employs an electrical shock obtained from a 9-V dry cell to deliver a consistent and effective current amplitude of 0.4μA (i.e., the US).
  
  
  RESULTS
  Using this apparatus, 10 snails can be conditioned simultaneously. We found that the optimal parameters to result in both short (STM) and long-term memory (LTM) were 15 paired presentations of the CS and US with a 5-min inter-trial interval (ITI) and 0.2-s current duration. However, both STM and LTM were observed with other ITIs tested. Successful TAC with only a single pairing of the CS-US occurred with a CS of 100mM sucrose solution for 60s followed by a US of 9V with 0.4μA for 5s.
  
  
  CONCLUSIONS
  The use of automated training apparatus for TAC will enable us to better examine the relationship between strength of CS and US.
authors.affiliation: Graduate School of Bioscience, Tokai University, 317 Nishino, Numazu 410-0321, Shizuoka, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Takigami
authors.affiliation: Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Calgary, AB, Canada T2N 4N1.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sunada
authors.affiliation: Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Calgary, AB, Canada T2N 4N1.
authors.forename: Ken
authors.initials: K
authors.lastname: Lukowiak
authors.affiliation: Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University, Sanuki 769-2193, Japan.
authors.forename: Etsuro
authors.initials: E
authors.lastname: Ito
authors.affiliation: Graduate School of Bioscience, Tokai University, 317 Nishino, Numazu 410-0321, Shizuoka, Japan. Electronic address: manabu@tokai.ac.jp.
authors.forename: Manabu
authors.initials: M
authors.lastname: Sakakibara
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D003214:Conditioning, Classical / Q000502:physiology*; D008195:Lymnaea / Q000502:physiology*; D057567:Memory, Long-Term / Q000502:physiology*; D008570:Memory, Short-Term / Q000502:physiology*; D009483:Neuropsychological Tests; D013997:Time Factors
keywords: Control of temporal sequence; Inter-trial interval; Long-term memory; One-trial conditioning; Paired presentation of conditional and unconditional stimuli; Short-term memory; Stimulus duration; Temporal stimulus parameters