Comparative effects of different test day challenges on performance in the 5-choice serial reaction time task

Abstract

The 5-choice serial reaction time task (5-CSRTT) is a valuable cognitive test that permits the simultaneous assessment of several different cognitive modalities, including attention, impulse control, processing speed, and cognitive flexibility. Increasing task difficulty on test days through various challenges can further enhance the versatility of this test by selectively enhancing the cognitive load on different aspects of the task. Systematic comparisons of the effects of different test day challenges on 5-CSRTT performance are essential to verify how these challenges affect different task measures and which manipulations are best suited for future studies of different aspects of cognition. We trained Wistar rats in the 5-CSRTT under standard conditions, then challenged them on the test days by (1) decreasing the duration of the stimulus to be detected, (2) increasing the time interval between trials (intertrial interval, ITI), (3) randomly varying the ITI, or (4) adding a flashing light distractor. All test day challenges produced distinct profiles of performance disruption that reflected differential effects on different cognitive modalities. Decreased stimulus duration selectively impaired attentional performance, while increased ITI increased impulsive-like premature responses and decreased trials completed. Variable ITI induced only mild, nonsignificant disruptions in response inhibition and processing speed, while the flashing light distractor produced comprehensive impairment affecting multiple aspects of 5-CSRTT performance, including disrupted attention and increased premature and timeout responses. This improved understanding of the effects of different test day challenges in the 5-CSRTT will allow researchers to use these manipulations of a valuable cognitive test to their full potential.

Figure 1. Effects of decreased stimulus duration on the test day on 5-CSRTT performance

Accuracy (A), percent correct responses (B), percent incorrect responses (C), percent omissions (D), total trials (E), premature response rate (F), perseverative response rate (G), timeout response rate (H), latency to correct response (I), and latency to reward retrieval (J) are expressed as mean ± SEM. Asterisks (**p < 0.01, ***p < 0.001) denote statistically significantly differences in performance during the reduced stimulus duration challenge compared with performance under baseline task conditions. Pound signs (^#p < 0.1) denote a trend toward differences during the reduced stimulus duration challenge compared with performance under baseline task conditions. Baseline, performance under baseline task conditions; decreased SD, performance during the reduced stimulus duration challenge.

Figure 2. Effects of increased intertrial interval on the test day on 5-CSRTT performance

Accuracy (A), percent correct responses (B), percent incorrect responses (C), percent omissions (D), total trials (E), premature response rate (F), perseverative response rate (G), timeout response rate (H), latency to correct response (I), and latency to reward retrieval (J) are expressed as mean ± SEM. Asterisks (*p < 0.05, ***p < 0.001) denote statistically significantly differences in performance during the increased intertrial interval challenge compared with performance under baseline task conditions. Pound signs (^#p < 0.1) denote a trend toward differences during the increased intertrial interval challenge compared with performance under baseline task conditions. Baseline, performance under baseline task conditions; increased ITI, performance during the increased intertrial interval challenge.

Figure 3. Effects of variable intertrial interval on the test day on 5-CSRTT performance

Accuracy (A), percent correct responses ( B), percent incorrect responses (C), percent omissions (D), total trials (E), premature response rate (F), perseverative response rate (G), timeout response rate (H), latency to correct response (I), and latency to reward retrieval (J) are expressed as mean ± SEM. Pound signs (^#p < 0.1) denote a trend toward differences during the variable intertrial interval challenge compared with performance under baseline task conditions. Baseline, performance under baseline task conditions; variable ITI, performance during the variable intertrial interval challenge.

Figure 4. Effects of a flashing light distractor on the test day on 5-CSRTT performance

Accuracy (A), percent correct responses (B), percent incorrect responses (C), percent omissions (D), total trials (E), premature response rate (F), perseverative response rate (G), timeout response rate (H), latency to correct response (I), and latency to reward retrieval (J) are expressed as mean ± SEM. Asterisks (*p < 0.05, **p < 0.01, ***p < 0.001) denote statistically significantly differences in performance during the flashing light distractor challenge compared with performance under baseline task conditions. Baseline, performance under baseline task conditions; flashing light, performance during the flashing light distractor challenge.