Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Jun 15;27(7):270-274.
doi: 10.1101/lm.051557.120. Print 2020 Jul.

Reducing shock imminence eliminates poor avoidance in rats

Affiliations

Reducing shock imminence eliminates poor avoidance in rats

Lindsay C Laughlin et al. Learn Mem. .

Abstract

In signaled active avoidance (SigAA), rats learn to suppress Pavlovian freezing and emit actions to remove threats and prevent footshocks. SigAA is critical for understanding aversively motivated instrumental behavior and anxiety-related active coping. However, with standard protocols ∼25% of rats exhibit high freezing and poor avoidance. This has dampened enthusiasm for the paradigm and stalled progress. We demonstrate that reducing shock imminence with long-duration warning signals leads to greater freezing suppression and perfect avoidance in all subjects. This suggests that instrumental SigAA mechanisms evolved to cope with distant harm and protocols that promote inflexible Pavlovian reactions are poorly designed to study avoidance.

PubMed Disclaimer

Figures

Figure 1.
Figure 1.
Reducing US imminence leads to perfect avoidance. (A) Mean percent avoidance by session. (B) Mean avoidance response (AR) latency by session. (inset) mean AR latency for individuals during Session 10. (C) Mean seconds freezing during warning signals for sessions 1, 6, and 10. (D) Mean Session 10 freezing expressed as a percentage of Session 1 freezing. (E) Mean number of shuttles per WS (separate experiment). Dots represent individuals. N = 8/group (4 females, 4 males except for Master (240 sec) group: 5 females, 3 males). Error bars = S.E.M. (*) P < 0.05 versus 15 sec-WS or Master groups.
Figure 2.
Figure 2.
Reducing the WS:ITI ratio fails to impair avoidance with a 240 sec warning signal. (A) Total avoidance responses emitted across 10 sessions of training. (B) Mean percent avoidance by session. (C) Mean Session 10 freezing expressed as a percentage of Session 1 freezing. N = 8/group (four females, four males). Bars represent separate groups. Bar height indicates group mean. Dots represent individuals. Error bars = S.E.M. (*) P < 0.05 for 240 sec versus 60 sec WS groups.
Figure 3.
Figure 3.
Reducing WS–US contingency does not improve avoidance. (A) Mean percent avoidance by session. (B) Mean avoidance response (AR) latency by session. (C) Mean seconds freezing during warning signals for Sessions 1, 6, and 10. (D) Mean Session 10 freezing expressed as a percentage of Session 1 freezing. Squares represent individuals. N = 8/group (4 females, 4 males). Error bars = S.E.M. (*) P < 0.05 versus 100% WS–US contingency group.

References

    1. APA. 2013. Diagnostic and statistical manual of mental disorders. American Psychiatric Publishing, Arlington, VA.
    1. Archer T, Ogren S, Johansson G. 1984. Stimulus conditions affecting the rate of acquisition in a computer-operated version of the two-way active avoidance procedure. Scand J Psychol 25: 89–95. 10.1111/j.1467-9450.1984.tb01003.x - DOI
    1. Balsam PD, Drew MR, Gallistel CR. 2010. Time and associative learning. Comp Cogn Behav Rev 5: 1–22. 10.3819/ccbr.2010.50001 - DOI - PMC - PubMed
    1. Blanchard RJ, Blanchard DC. 1989. Antipredator defensive behaviors in a visible burrow system. J Comp Psychol 103: 70–82. 10.1037/0735-7036.103.1.70 - DOI - PubMed
    1. Blanchard RJ, Blanchard DC, Hori K. 1989. Ethoexperimental approaches to the study of defensive behavior. In Ethoexperimental approaches to the study of behavior (ed. Blanchard RJ, Brain PF, Blanchard DC, Parmigiani S), pp. 114–136. Kluwer Academic Publishers, Dordrecht.

Publication types

LinkOut - more resources