Mice and rats fail to integrate exogenous timing noise into their time-based decisions

Abstract

Endogenous timing uncertainty results in variability in time-based judgments. In many timing tasks, animals need to incorporate their level of endogenous timing uncertainty into their decisions in order to maximize the reward rate. Although animals have been shown to adopt such optimal behavioral strategies in time-based decisions, whether they can optimize their behavior under exogenous noise is an open question. In this study, we tested mice and rats in a task that required them to space their responses for a minimum duration (DRL task) in different task conditions. In one condition, the minimum wait time was fixed, whereas in other conditions minimum wait time was a Gaussian random variable. Although reward maximization entailed waiting longer with added exogenous timing variability, results indicated that both mice and rats became more impulsive and deviated from optimality with increasing levels of exogenous noise. We introduce a reward-rate-dependent sampling function to SET to account for optimal performance in noiseless and suboptimal performance in noisy environments.

Interval timing is disrupted in female 5xFAD mice: An indication of altered memory processes

“…The current study demonstrated an interval timing deficit in a mouse model of AD and the interpretation of the results within the SET conceptual framework suggested that the observed behavioral phenotype was due to altered consolidation of temporal memories. Future studies are required to evaluate the generalizability of this difference to male 5xFAD mice and to data collected with other timing procedures such as temporal bisection (Akdoğan & Balcı, ; Church & Deluty, ), switch procedure (Balcı, Papachristos, et al, ), and differential reinforcement of low rates of responding (Berkay, Freestone, & Balcı, ; Gür & Balcı, ). Finally, future studies would further inform the validity of our memory processing‐based interpretation of the behavioral results by testing the same mice in behavioral tasks that have revealed a memory phenotype in this model of AD (e.g., novel object recognition, contextual fear conditioning).…”

Monitoring line length reproduction errors

“…Thus, in line with our speculation, the effect of non-scalar (non-representational) sources of variability appears to have stronger manifestation than the scalar sources of representational uncertainty for the shortest target length of Experiment 1. If metric error monitoring (including confidence ratings as a proxy for error magnitude rating) relies primarily on representational scalar uncertainty, the stronger manifestation of non-scalar sources of variability could indeed limit the metric error monitoring performance (for a similar argument in animal decision-making see (Berkay, Freestone, & Balcı, 2016)). Future studies are needed to fully address this possibility.…”