The touchscreen cognitive testing method for rodents: how to get the best out of your rat - PubMed (original) (raw)

. 2008 Jul 8;15(7):516-23.

doi: 10.1101/lm.987808. Print 2008 Jul.

Affiliations

The touchscreen cognitive testing method for rodents: how to get the best out of your rat

Timothy J Bussey et al. Learn Mem. 2008.

Abstract

The touchscreen testing method for rodents is a computer-automated behavioral testing method that allows computer graphic stimuli to be presented to rodents and the rodents to respond to the computer screen via a nose-poke directly to the stimulus. The advantages of this method are numerous; however, a systematic study of the parameters that affect learning has not yet been conducted. We therefore sought to optimize stimuli and task parameters in this method. We found that when parameters were optimized, Lister Hooded rats could learn rapidly using this method, solving a discrimination of two-dimensional stimuli to a level of 80% within five to six sessions lasting approximately 30 min each. In a final experiment we tested both male and female rats of the albino Sprague-Dawley strain, which are often assumed to have visual abilities far too poor to be useful for studies of visual cognition. The performance of female Sprague-Dawley rats was indistinguishable from that of their male counterparts. Furthermore, performance of male Sprague-Dawley rats was indistinguishable from that of their Lister Hooded counterparts. Finally, Experiment 5 examined the ability of Lister Hooded rats to learn a discrimination between photographic stimuli. Under conditions in which parameters were optimized, rats were remarkably adept at this discrimination. Taken together, these experiments served to optimize the touchscreen method and have demonstrated its usefulness as a high-throughput method for the cognitive testing of rodents.

PubMed Disclaimer

Figures

Figure 1.

Figure 1.

(A) The rat touchscreen apparatus. One wall of a standard operant chamber was removed and replaced with a flat-screen monitor and touchscreen assembly. A Perspex “mask” was placed over the screen; this was a sheet of Perspex that covered the screen with two response windows through which the rat could make a nose-poke toward the screen. Attached to the mask was a “shelf,” the effect of which was to force the rat to stop, rear up, and stretch toward the stimuli with a head-on approach, thus facilitating the rat’s attention to the stimuli. The magazine containing built-in photocells was located on the rear wall (not shown). (B) Pairs of stimuli used in Experiment 1. Pairs 1, 2, 3, and 6 were used in Experiment 2. Pair 2 was used for Experiments 3 and 4.

Figure 2.

Figure 2.

Results of bias tests (Experiment 1) for the six stimulus pairs. Rats showed a significant bias to respond to one of the two stimuli in pair 4 only.

Figure 3.

Figure 3.

Acquisition curves of rats performing visual discriminations with different stimulus sizes (Experiment 2). Rats acquired the discrimination most rapidly when the largest stimuli were used.

Figure 4.

Figure 4.

(A) Acquisition curves of rats performing visual discriminations with different combinations of task parameters. Data are plotted as blocks of three sessions. Rats were tested with all combinations of initiation or no initiation, 20 trials or 60 trials, and short or long ITI. A requirement for initiation (B), a larger number of trials (C), and a long ITI (D) all significantly facilitated acquisition.

Figure 5.

Figure 5.

Learning curves and sessions to criterion for Sprague-Dawley male rats compared with those for Sprague-Dawley female rats (acquisition, A; reversal, B), and for Sprague-Dawley (SD) male rats compared with Lister Hooded (LH) male rats (C). All groups of rats acquired the task equally rapidly.

Figure 6.

Figure 6.

(A) Acquisition curve of rats performing a visual discrimination using photographic stimuli. Rats attained levels above 80% correct within 14 sessions of 60 trials each. (B) Photographic stimuli filtered to provide an approximation of how the stimuli might appear to rodents with a visual acuity of 1.0 cycle/degree, when viewing the stimuli from different distances. Based on the analysis by Prusky et al. (2002).

References

    1. Barnet R.A., Grahame N.J., Miller R.R. Trial spacing effects in Pavlovian conditioning: A role for local context. Anim. Learn. Behav. 1995;23:340–348.
    1. Brigman J., Bussey T.J., Saksida L.M., Rothblat L. Discrimination of multidimensional visual stimuli by mice: Intra- and extradimensional shifts. Behav. Neurosci. 2005;118:839–842. - PubMed
    1. Bussey T.J., Muir J.L., Robbins T.W. A novel automated touchscreen procedure for assessing learning in the rat using computer graphic stimuli. Neurosci. Res. Commun. 1994;15:103–110.
    1. Bussey T.J., Everitt B.J., Robbins T.W. Dissociable effects of cingulate and medial frontal cortex lesions on stimulus-reward learning using a novel Pavlovian autoshaping procedure for the rat: Implications for the neurobiology of emotion. Behav. Neurosci. 1997a;111:908–919. - PubMed
    1. Bussey T.J., Muir J.L., Everitt B.J., Robbins T.W. Triple dissociation of anterior cingulate, posterior cingulate, and medial frontal cortices on visual discrimination tasks using a touchscreen testing procedure for the rat. Behav. Neurosci. 1997b;111:920–936. - PubMed

Publication types

MeSH terms

LinkOut - more resources