Measuring attention in rodents: comparison of the 5-choice serial reaction time task (5C-SRT) and continuous detection task (CDT)

• ¹ The University of Queensland, Queensland Brain Institute, Australia
• ² Queensland Centre for Mental Health Research, Australia

One drawback in assessing cognition in rodents has been the extensive training time and low throughput required using operant tasks, and this is of particular importance for preclinical drug screening. Therefore, the purpose of this study was to compare a novel continuous detection task (CDT) with the traditional 5-choice serial reaction time task (5C-SRT) as measures of attention in rats. Male Sprague-Dawley rats were food restricted and trained on either the 5C-SRT or the novel CDT (n=18/group). Briefly, the 5C-SRT required rodents to pay attention to an array of 5 holes and respond with a nose poke to a light within a hole. The CDT differs by using a central panel of 9 LEDs and the rat makes a nose poke response to either the left or right of the central array to indicate the presence or absence of a signal. Therefore, an abstract rule must be maintained, as the signal position does not indicate the correct response location. Both tasks ran for 120 trials per session and were rewarded with 45mg grain pellets. Following training, the signal duration was reduced on both tasks to provide a comparable measure of increasing attentional load. The number of daily sessions required to reach criteria was significantly greater for 5C-SRT (31±2) than for the CDT (18±1) (t(34)=6.1,p<0.001). Session duration was also significantly reduced on the CDT (25 vs. 9min; p<0.001). Both groups of rats performed to a high level of accuracy (>87%), which was reduced with decreasing signal duration and this did not differ between protocols. However, the 5C-SRT included more omissions per session (14±1) than the CDT (0±0). In summary, compared to the 5C-SRT, there were fewer training sessions, reduced session duration and fewer omissions on the CDT. In addition, signal detection indices, used for investigating decision-making processes, can be derived from the CDT. Thus, the CDT demonstrates higher throughput and reduced response ambiguity on a rodent task assessing executive functioning.