Assessing Mongolian gerbil emotional behavior: effects of two shock intensities and response-independent shocks during an extended inhibitory-avoidance task

Abstract

Despite step-down inhibitory avoidance procedures that have been widely implemented in rats and mice to study learning and emotion phenomena, performance of other species in these tasks has received less attention. The case of the Mongolian gerbil is of relevance considering the discrepancies in the parameters of the step-down protocols implemented, especially the wide range of foot-shock intensities (i.e., 0.4–4.0 mA), and the lack of information on long-term performance, extinction effects, and behavioral patterning during these tasks. Experiment 1 aimed to (a) characterize gerbils’ acquisition, extinction, and steady-state performance during a multisession (i.e., extended) step-down protocol adapted for implementation in a commercially-available behavioral package (Video Fear Conditioning System—MED Associates Fairfax, VT, USA), and (b) compare gerbils’ performance in this task with two shock intensities – 0.5 vs. 1.0 mA—considered in the low-to-mid range. Results indicated that the 1.0 mA protocol produced more reliable and clear evidence of avoidance learning, extinction, and reacquisition in terms of increments in freezing and on-platform time as well as suppression of platform descent. Experiment 2 aimed to (a) assess whether an alternate protocol consisting of a random delivery of foot shocks could replicate the effects of Experiment 1 and (b) characterize gerbils’ exploratory behavior during the step-down task (jumping, digging, rearing, and probing). Random shocks did not reproduce the effects observed with the first protocol. The data also indicated that a change from random to response-dependent shocks affects (a) the length of each visit to the platform, but not the frequency of platform descends or freezing time, and (b) the patterns of exploratory behavior, namely, suppression of digging and rearing, as well as increments in probing and jumping. Overall, the study demonstrated the feasibility of the extended step-down protocol for studying steady performance, extinction, and reacquisition of avoidance behavior in gerbils, which could be easily implemented in a commercially available system. The observation that 1.0 mA shocks produced a clear and consistent avoidance behavior suggests that implementation of higher intensities is unnecessary for reproducing aversive-conditioning effects in this species. The observed patterning of freezing, platform descents, and exploratory responses produced by the change from random to periodic shocks may relate to the active defensive system of the gerbil. Of special interest is the probing behavior, which could be interpreted as risk assessment and has not been reported in other rodent species exposed to step-down and similar tasks.

Using Principles from Applied Behaviour Analysis to Address an Undesired Behaviour: Functional Analysis and Treatment of Jumping Up in Companion Dogs

“…For the current analysis, Tau was chosen because it provides p-values (a p < 0.05 was considered statistically significant) and confidence intervals, and its values are directly interpretable [80,81]. Magnitude of level differences between conditions can be interpreted as higher values representing a larger effect, while lower values represent a weaker effect (e.g., ≤0.60 = weak effect, 0.61 to 0.92 = medium to large effect, and >0.93 = very large effect; [81][82][83][84]). Data for Experiments 1 and 2 can be found here: https://osf.io/3wg9a/ [85].…”

“…Animals 2019, 9, x 8 of 34 effect, 0.61 to 0.92 = medium to large effect, and > 0.93 = very large effect; [81][82][83][84]). Data for Experiments 1 and 2 can be found here: https://osf.io/3wg9a/ [85].…”

Diazepam Reduces Escape and Increases Closed-Arms Exploration in Gerbils After 5 min in the Elevated Plus-Maze

“…In fear conditioning and avoidance tests with shocks, rats freeze considerably more than gerbils, which results in better performance of rats in inhibitory tasks such as step-down and step-through avoidance. Conversely, gerbils show better adjustment to shuttle and lever-press avoidance, which entail active responses, including movement across the instrument (Ashe and McCain, 1972; Galvani et al, 1975; Powell et al, 1978; Crawford et al, 1981; Hurtado-Parrado et al, 2017).…”

“Swimming against the current”: Behavioral data of Betta splendens during an escape and avoidance task with water flows as the aversive stimulus

“…The sequence of baseline, UA and SA conditions to which each subject was exposed is detailed in Table 1. Subjects changed to the next programmed condition when a steady pattern of crossing responses was observed across sessions (criteria based on [7], [8], [9]). Fish C01, C02, and C03 were initially exposed to UA prior to experiencing SA.…”