Lightning talk - Room B (12:15 P.M.)

7. Chronic, inescapable and contiguity foot-shocks to feeding period modifies eating behavior in rats

Marina Liliana González-Torres-Department of psychology, Autonomous University of Aguascalientes, Aguascalientes, Aguascalientes, Mexico, Cristiano Valerio dos Santos-Research and Studies on Behavior Center, University of Guadalajara, Guadalajara, Jalisco, Mexico.

This study aimed to evaluate the differential effects of chronic middle inescapable shocks on feeding behavior applied before or after the feeding period, as well as the period of the light-dark cycle. Besides, in the first experiment investigated whether the possibility of escape from shocks differentially affects the food intake and the body weight gain in rats. In Experiment 1, we exposed two groups of rats to escape foot-shocks after baseline condition; if before or after food access in the dark period, the other two groups were yoked to the first, and a control group did not exposure to shocks. In the second experiment, inescapable shocks or no shocks occurred after or before to food access in the light period after the baseline condition in three groups of rats. Results suggest that chronic stress induced by electric shocks decrease food intake and body weight gain, especially with inescapable shocks, and when it occurred before food access, regardless of the time in which the electric shocks were administered. The findings support the link between uncontrollable and chronic stress and eating behavior, and they reveal the importance of contiguity of the stressor and the feeding period. Keywords: inescapable stressor, chronic stress, learned helplessness, food intake, contiguity to feeding period, rats..


8. Absence of latent inhibition in food aversion conditioning in Japanese fire-bellied newts

Weisheng Zhao-Kanazawa University, Tohru Taniuchi-Kanazawa University

The present study examined latent inhibition (CS preexposure effect) in food aversion conditioning in Japanese fire-bellied newts. Newts in Preexposure condition were presented a piece of 40 mg ground raw beef once a week for 15 weeks. Other foods were not given throughout the experiment. Newts in the Non-preexposure condition were given three 13 mg (wet weight) food pellets instead of the raw beef. In conditioning after the pre-exposure period, newts in both conditions were allowed to eat pieces of 40 mg raw beef (CS) scattered in a water tank for one hour. Immediately after the CS presentation, i.p. injections of LiCl (0.15M, 190 mg/kg) or saline (190 mg/kg) were given to Experimental and Control conditions, respectively. In the test conducted 12 days after the conditioning, rats in the Experimental conditions consumed less amount of CS food than in the Control conditions. However, any inhibitory effects by preexposure of CS food on conditioning were not observed. That is, any significant differences of strength of food aversion conditioning were not observed between Preexposure and Non-preexposure conditions. These results suggest absence of latent inhibition in food aversion conditioning in Japanese fire-bellied newts.


9. Renewal procedure (ABA) with light as context in snails Cornu aspersum

Judit Muñiz-Moreno - Universidad de Oviedo, Ignacio Loy - Universidad de Oviedo

Previous studies showed renewal effect in Cornu aspersum, using tentacle lowering conditioning procedure and the photoperiod (the hour of the day and presence of light) as context. However, this procedure can be simplified using only the presence of light as context, so this experiment was carried out for this purpose. It consisted of exposing an odour paired with access to food (CS+US) in a context during training. Then, subjects were exposed to the CS without the US during extinction phase. Furthermore, for half of the subjects, extinction phase was made in the same context whereas, for the other half, extinction phase was made in a different context than training. Finally, all the subjects were exposed to the CS in the same context as training during renewal test. The results showed that a return to the original training context produces a recovery of the conditioned response (CR) and it is consistent with the interference theories.

10. Effects of affective contexts on the reappearance of extinguished responses in rats

Diana Mireya Carreón Morales-Universidad Nacional Autónoma de México, Mariel Almaguer-Azpeitia-Universidad Nacional Autónoma de México, Javier Nieto- Universidad Nacional Autónoma de México, Rodolfo Bernal-Gamboa-Universidad Nacional Autónoma de México

In the renewal effect, the reappearance of an extinguished response is observed due to a change in context between the extinction and test phases. Among the interoceptive contexts, emotional states have become relevant since they are the least studied. In humans some attempts have been made to carry out contextual renewal studies with affective contexts, however it has not been explored in non-human animals. Now several investigations have shown that the tickling procedure in rats is a reliable procedure to study positive affective states. Therefore, the main goal of the present study was to explore and evaluate the effect of the positive emotional context (induced through the tickling procedure), in the recovery of an extinguished response in rats. We used an ABA renewal design. In the first phase, all rats were trained to press a lever for food, then in the next phase 2, the lever pressing received an extinction treatment. Finally, all rats were tested. Contexts were provided only by the tickling procedure, thus, rats in the ABA Group received tickles in phase 1 and 3, while, rats in ABB Group only received tickles in phase 1, and the Group BAA was tickled in phase 2 and 3. We found renewal only in the group that experienced an affective context-switch between phase 2 and 3 (ABA Group). We discussed our findings within a memory retrieval framework.

11. The ABA renewal of operant behavior is not reduced by the retrieval-extinction paradigm

Tere A. Mason-National University of Mexico, Rodolfo Bernal-Gamboa-National University of Mexico, Javier Nieto-National University of Mexico

In recent years, the response recovery after extinction effects have been received plenty attention of researchers, due to its possible implications for the development of strategies that can reduce relapse. An experiment with rats was conducted to analyze the impact of the retrieval-extinction paradigm on the ABA renewal of operant behaviors. In the first phase of the experiment, subjects were trained to press a lever for food in context A. Then, in Phase 2, the Extinction Group received the typical extinction procedure, whereas the Retrieval Group was exposed to the retrieval-extinction paradigm (i.e., a brief extinction session, followed by a retention interval, and then a longer extinction session). This phase was conducted for all groups in context B. Finally, all rats were tested twice. One test was carried out in context B, while the other test took place in context A (counterbalanced). We found similar levels of ABA renewal in both groups. We discussed the results within the contemporary extinction perspectives.

 


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