Rats’ midsession reversal performance: the nature of the response

Abstract

The midsession reversal task involves a simple simultaneous discrimination that predictably reverses midway through a session. Under various conditions, pigeons generally both anticipate the reversal and perseverate once it has occurred, whereas rats tend to make very few of either kind of error. In the present research, we investigated the hypothesis that the difference in performance between rats and pigeons is related to the nature of the responses made. We hypothesized that rats could have been better at bridging the intertrial interval by keeping the relevant paw close to the lever while eating, whereas the pigeons had to remove their beak from the response key and insert it into the feeder, thus making it difficult to mediate the response last made. In the present experiment, in successive phases, rats were trained to leverpress or nose-poke on a 40-trial midsession reversal, an 80-trial midsession reversal, and a variable-location reversal. The results showed that the leverpress group acquired the task faster than the nose-poke group, but that both groups reached comparable levels of performance. Thus, the difference in the natures of the responses cannot fully account for the differences in accuracy between rats and pigeons. Additionally, differences in the types of errors made by the two groups suggest that the nature of the response plays different roles in the performance of this task.

The Organization of Behavior over Time: Insights from Mid-session Reversal

“…Although several newer studies have illuminated how changes in task demands can modulate the degree of this temporal control (Daniel et al, 2015; McMillan et al, 2014; McMillan & Roberts, 2012; McMillan et al, 2016; Rayburn-Reeves, Laude, et al, 2013; Rayburn-Reeves et al, under review), it is unclear why time has such a powerful influence on this species. Humans, and perhaps all mammals, appear to be far less influenced by time and more likely to attend to recent outcomes in guiding their switching behavior (Rayburn-Reeves et al, 2011; Rayburn–Reeves, Stagner, et al, 2013; A. P. Smith et al, 2016).…”

“…Many studies have attempted to reduce the relevancy and predictability of the timing cue by randomly varying across sessions the trial at which the discrimination reversal occurs (McMillan, Kirk, & Roberts, 2014; McMillan, Sturdy, Pisklak, & Spetch, 2016; Rayburn-Reeves, Laude, & Zentall, 2013; Rayburn-Reeves et al, 2011; Rayburn-Reeves & Zentall, 2013; A. P. Smith, Pattison, & Zentall, 2016).…”

“…The majority of errors occurred only on the first reversal trial. In a similar study, Smith et al (2016) trained two groups of rats on an MSR spatial task with 5 s ITI durations using either lever presses or nose-pokes as the two choice response manipulanda. Both groups showed similar acquisition rates to each other and very few errors around the reversal, suggesting that the nature of the response is not critical to the rats.…”

It's All a Matter of Time: Interval Timing and Competition for Stimulus Control

“…Fundamentally, pigeons' responding across these sessions appears to be probabilistic rather than categorical, despite that the reversal itself is from 100% to 0% probability of reward (or vice versa). Research has soundly demonstrated the robustness of the midsession reversal timing errors even with variable, difficultto-predict reversal points (Rayburn-Reeves, Laude, & Zentall, 2013;Smith, Pattison, & Zentall, 2016). Even when actual switch points vary wildly across sessions, pigeons appear to form molar aggregate computations to anticipate the switch, and make only modest corrections based on a molecular "follow the reward" rule (Rayburn-Reeves, Laude, et al, 2013).…”

Change in the relative contributions of habit and working memory facilitates serial reversal learning expertise in rhesus monkeys

“…There has been a resurgence in interest in reversal learning, manifest in a raft of recent studies of “midsession reversal” (McMillan et al 2014; Rayburn-Reeves, et al 2011; Smith et al 2016; Stagner et al 2013). Generally, these studies find that pigeons make many anticipatory and perseverative errors when a reversal predictably occurs in the middle of a testing session.…”