Awareness of errors and feedback in human time estimation

Behavioral and electrophysiology studies have shown that humans possess a certain self-awareness of their individual timing ability. However, conflicting reports raise concerns about whether humans can discern the direction of their timing error, calling into question the extent of this timing awareness. To understand the depth of this ability, the impact of nondirectional feedback and reinforcement learning on time perception were examined in a unique temporal reproduction paradigm that involved a mixed set of interval durations and the opportunity to repeat every trial immediately after receiving feedback, essentially allowing a “redo.” Within this task, we tested two groups of participants on versions where nondirectional feedback was provided after every response, or not provided at all. Participants in both groups demonstrated reduced central tendency and exhibited significantly greater accuracy in the redo trial temporal estimates, showcasing metacognitive ability, and an inherent capacity to adjust temporal responses despite the lack of directional information or any feedback at all. Additionally, the feedback group also exhibited an increase in the precision of responses on the redo trials, an effect not observed in the no-feedback group, suggesting that feedback may specifically reduce noise when making a temporal estimate. These findings enhance our understanding of timing self-awareness and can provide insight into what may transpire when this is disrupted.

The tendency to reflect on one''s mental state, or metacognition, is an essential human trait that is a central component of consciousness, memory processing, language, and decision-making, and, most importantly, time perception (Fleming and Dolan 2012; Yeung and Summerfield 2012). Accurate time perception is also a hallmark of consciousness and critical for everyday behaviors and cognitive functions ranging from speech, motor control, adaptive behavior, and survival (Meck 2005; Grondin 2010). Self-assessment of one''s own timing ability without any external feedback, known as temporal metacognition, is vital for reliably determining temporal accuracy and variance despite uncertainty (Balcı et al. 2011; Lamotte et al. 2012; Akdoğan and Balcı 2017). Past research shows that humans and rodents can successfully incorporate the endogenous timing uncertainty and trial-by-trial variability associated with time perception tasks into their behavioral responses in a way that maximizes performance, updates temporal representations, and boosts reward (Balcı et al. 2011; Li and Dudman 2013). Human performance is measured via interval timing tasks that instruct participants to estimate temporal intervals of several seconds (Buhusi and Meck 2005). One particular task, temporal reproduction, involves exposure to a specific duration (encoding) and then an opportunity to recreate the interval duration via keypress (reproduction), with or without feedback. Previous research has shown that human subjects can accurately infer the distribution of intervals presented, and use this information to guide reproductions in the phase of measurement uncertainty (Jazayeri and Shadlen 2010; Acerbi et al. 2012). While the evidence already points toward an existing self-awareness of time, evaluating timing aptitude in context of feedback and learning may broaden our understanding of internal metacognitive process and its role in time perception.Detecting and correcting errors is an important component for metacognition and self-awareness of one''s cognitive state (Fleming and Dolan 2012; Yeung and Summerfield 2012). The brain''s performance monitoring system is responsible for assessing and minimizing these errors and facilitating the selection of an appropriate motor program to successfully complete the chosen task or behavior (Ullsperger et al. 2014). Error tracking mechanisms have been reported for temporal, numerosity, and spatial errors, implying that there may be a common metric error-monitoring system that underpins magnitude-based representations (Duyan and Balcı 2019). In particular, how errors related to early or late timing either with or without external feedback are managed is not fully understood. Studies on the impact of feedback on time perception have produced conflicting results, particularly due to the variability in the type of feedback delivery. Experimental timing paradigms offer a broad array of options ranging from no feedback, magnitude and directional feedback, magnitude-based feedback only, or directional-only feedback. Our study is an initial assessment of whether there is self-awareness of directional temporal information and compares the no feedback and magnitude-based conditions, serving as a launching point for further studies.Akdoğan and Balcı (2017) used a temporal reproduction task to assess how subjects reproduced a range of suprasecond intervals; their findings demonstrated that humans are aware of both the magnitude and direction (early/late) of their timing errors despite not receiving any external feedback. Another recent behavioral study used a temporal production task, in which subjects were asked to repeatedly produce a single duration (3 sec) and compared performance during a condition when only the magnitude of the error was given (absolute) against another condition in which both the magnitude and direction (signed) were given (Riemer et al. 2019). Signed feedback delivery yielded more behavioral adjustments in opposition to the direction of the error in subsequent trials, reduced bias in temporal estimates, and produced a more accurate and better calibrated performance when compared with absolute feedback. This study illustrated that directional information was not intrinsically accessible to the subject and that the participant''s internal timing error representation failed to include that error direction. Furthermore, subjects assigned to the absolute feedback group also tended to report an overreproduction of the interval duration when in reality, they were underreproducing (Riemer et al. 2019). A key difference should be noted between these two studies, notably that feedback and retrospective self-judgments respectively were given following an entire block (Riemer et al. 2019) rather than trial by trial as in the Akdoğan and Balcı (2017) experiment. Task context also played a crucial role, as different tasks were used for the two studies; Akdoğan and Balcı (2017) used a temporal reproduction with a mixed set of intervals while Riemer et al. (2019) used a temporal production task with a singly presented interval.In addition to simply supplying knowledge and guidance about the response (Salmoni et al. 1984), feedback has numerous other uses. It reduces response drifts over the experimental trajectory (Salmoni et al. 1984; Riemer et al. 2019) and may be erroneous or correct, but our study concentrates on correct feedback that tends to positively adjust behavioral responses (Salmoni et al. 1984). Its delivery may be absolute—after every trial or on a percentage of trials (relative). Additionally, feedback can be a motivational factor and act as an implicit reward for behavioral learning (Salmoni et al. 1984; Tsukamoto et al. 2006). Posterror feedback can also facilitate the learning of time intervals (Ryan and Robey 2002). Feedback may be processed differently depending on the quality of the learners and is reflected in a well-functioning performance monitoring system (Luft et al. 2013).Numerous timing studies demonstrate that participants are aware of their errors prior to or independent of the administration of feedback (Akdoğan and Balcı 2017; Brocas et al. 2018; Kononowicz et al. 2018). In a recent M/EEG study using a temporal production task with the objective of repeatedly producing the same single interval duration, Kononowicz et al. (2018) asked respondents to first judge their own performance. Afterwards, they were provided with 100% directional feedback in two blocks out of the six and 15% feedback on the remaining blocks. The initial self-assessment of their performance prior to feedback matched the true interval duration and β power operated as an index of the actual duration and the self-evaluative ability to track timing errors (Kononowicz et al. 2018). In yet another single duration temporal production study, Brocas et al. (2018) tasked participants to generate interval durations of 30+ sec repeatedly for 10 trials and introduced a reward scheme to incentivize making accurate temporal estimates. Similarly to Riemer''s paradigm, participants accurately self-evaluated their performance after a block of trials and correctly identified what proportion of trials were above or below the target interval duration (Brocas et al. 2018). Although accurate in their assessments of bias or tendency to overestimate or underestimate, the participants were less successful in prediction beforehand or correction of their responses (Brocas et al. 2018).Self-knowledge about your internal timing behavior also incorporates reinforcement learning, another adaptive behavioral operation that integrates previous behavioral experiences and applies them to future scenarios to improve outcomes and maximize future rewards (Lee et al. 2012). Predicting the value of a set action along with its outcome and determining whether it will be awarded involves precise timing mechanisms (Petter et al. 2018; Mikhael and Gershman 2019). Errors are prone to occur in this process, particularly when there is a mismatch between the expected and actual outcomes, manifesting itself in the form of a reward prediction error (RPE) (Hollerman and Schultz 1998).Notwithstanding errors, the process of learning interval durations transpires fairly quickly and is achieved with only one trial (Simen et al. 2011). To measure the speed of temporal learning, Simen et al. (2011) devised the “beat the clock task,” a paradigm where a green square is displayed on a computer screen for an unknown amount of time. It remains onscreen until the appearance of a red square outline signals that the interval is ending. Participants must respond with a keypress before the stimulus terminates and are rewarded for on-time responses. Larger rewards are delivered the closer a participant makes an on-time response (Simen et al. 2011). Although the task comprises mixed interval durations that transition rapidly, early responding is minimized and on-time responding becomes the norm as participants learn the structure of the task. It is noteworthy that despite the endogenous timing uncertainty stemming from the presentation of rapidly changing durations, performance improvement was not impeded (Simen et al. 2011). In fact, all beat the clock participants improved in response times after only a single trial of beat-the-clock task, quickly reduced their timing errors, and were able to implement a strategy that facilitated learning interval durations (Simen et al. 2011).Using an appropriate feedback technique is pivotal to understanding self-timing awareness. The traditional feedback structure in psychophysics studies is best suited for single interval reproductions because the same interval is successively reproduced; therefore, the majority of the studies described above are single interval experiments. Challenges arise when reproducing a random set of a mixed range of intervals because corrective guidance is given on one interval duration, yet the next interval may be of a different duration (Ryan 2016). This is problematic since there is no opportunity to use the feedback from the previous trial to the new trial, so the feedback is frequently misapplied to an entirely different duration (Ryan 2016). To rectify this issue, we introduced a “redo” trial, which allows the subject to use the original feedback from the first trial in a second trial of the same duration. We hypothesized that the redo trials will be beneficial to subjects for improving performance and in minimizing the Vierordt effect (underestimation of long intervals and overestimation of short intervals) (Ryan 2016). It is for this reason our study also incorporated absolute (nondirectional) feedback: to assess whether subjects possess awareness of the direction of the timing errors. If there is a substantial directional awareness of timing error, then the central tendency would be reduced.