One-trial associative learning modifies food odor preferences of a terrestrial mollusc

The cells which are described in this study surround the salivary nerve of the terrestrial mollusc, Limax maximus. The salivary system of Limax consists of bilateral glands, ducts, and nerves. The salivary nerves originate at the buccal ganglia, which are situated on the posterior face of the buccal mass, and run along the salivary duct to the gland. The salivary nerve branches several times near the gland, and eventually sends processes into the gland.The pore cells begin to appear at the first large branch point of the salivary nerve, near the gland (Figure 1). They follow the nerve distally and eventually accompany the nerve branches into the gland tissue. The cells are 20-50 microns in diameter and contain very small nuclei (1-5 microns) (Figure 2).The cytoplasm of the pore cells is segregated into a storage area of glycogen and an organelle region located in a band around the cell periphery (Figure 3).

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Blocking Is Sensitive to Causal Structure in 4-Year-Old and 8-Year-Old Children

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169.52.4.264 ◽

2005 ◽

Vol 52 (4) ◽

pp. 264-271 ◽

Cited By ~ 4

Author(s):

Tom Beckers ◽

Uschi Van den Broeck ◽

Marij Renne ◽

Stefaan Vandorpe ◽

Jan De Houwer ◽

...

Keyword(s):

Young Children ◽

Associative Learning ◽

Learning Theory ◽

Causal Structure ◽

Age Groups ◽

Learning Task ◽

Contingency Learning

Abstract. In a contingency learning task, 4-year-old and 8-year-old children had to predict the outcome displayed on the back of a card on the basis of cues presented on the front. The task was embedded in either a causal or a merely predictive scenario. Within this task, either a forward blocking or a backward blocking procedure was implemented. Blocking occurred in the causal but not in the predictive scenario. Moreover, blocking was affected by the scenario to the same extent in both age groups. The pattern of results was similar for forward and backward blocking. These results suggest that even young children are sensitive to the causal structure of a contingency learning task and that the occurrence of blocking in such a task defies an explanation in terms of associative learning theory.

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Learned Placebo Effects in the Immune System

Zeitschrift für Psychologie ◽

10.1027/2151-2604/a000184 ◽

2014 ◽

Vol 222 (3) ◽

pp. 148-153 ◽

Cited By ~ 2

Author(s):

Sabine Vits ◽

Manfred Schedlowski

Keyword(s):

Nervous System ◽

Immune System ◽

Associative Learning ◽

Placebo Response ◽

Immunosuppressive Drug ◽

Immune Functions ◽

Placebo Effects ◽

New Therapeutic Approaches ◽

Biological Variables ◽

Experimental Approaches

Associative learning processes are one of the major neuropsychological mechanisms steering the placebo response in different physiological systems and end organ functions. Learned placebo effects on immune functions are based on the bidirectional communication between the central nervous system (CNS) and the peripheral immune system. Based on this “hardware,” experimental evidence in animals and humans showed that humoral and cellular immune functions can be affected by behavioral conditioning processes. We will first highlight and summarize data documenting the variety of experimental approaches conditioning protocols employed, affecting different immunological functions by associative learning. Taking a well-established paradigm employing a conditioned taste aversion model in rats with the immunosuppressive drug cyclosporine A (CsA) as an unconditioned stimulus (US) as an example, we will then summarize the efferent and afferent communication pathways as well as central processes activated during a learned immunosuppression. In addition, the potential clinical relevance of learned placebo effects on the outcome of immune-related diseases has been demonstrated in a number of different clinical conditions in rodents. More importantly, the learned immunosuppression is not restricted to experimental animals but can be also induced in humans. These data so far show that (i) behavioral conditioned immunosuppression is not limited to a single event but can be reproduced over time, (ii) immunosuppression cannot be induced by mere expectation, (iii) psychological and biological variables can be identified as predictors for this learned immunosuppression. Together with experimental approaches employing a placebo-controlled dose reduction these data provide a basis for new therapeutic approaches to the treatment of diseases where a suppression of immune functions is required via modulation of nervous system-immune system communication by learned placebo effects.

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