A systematic examination of the neural correlates of subjective time perception with fMRI and tDCS.

The ability to keep track of time is one of the fundamental human behaviours that enhance survival in the wild. It is still an essential skill that enables an individual to function well in modern society. In the present study, we tested the attentional gate model, one of the most common conceptual frameworks in studies of subjective time perception. Its utility has been well established, but it has been criticised for its lack of neurophysiological support; few studies attempted to systematically identify its components and their neural correlates. Previous studies established that the dorsolateral prefrontal cortex (DLPFC) was associated with working memory tasks and a correlation between activity in the cerebellum and the timing of tasks. An fMRI study was conducted to confirm that these two cortical regions were activated during the execution of a new time discrimination task that considers individual variations in subjective time perception. Simulations were conducted to optimize the electrode placement in order to maximize the electric fields of tDCS perturbation to these two areas. According to the attentional gate model, hypotheses about tDCS perturbation to subjective time perception, attention and working memory were formulated and tested. Attention and working memory were measured by the attention network and N-back tasks. There are weak effects to the perceived subjective equivalent and the reaction time in the attention network task, but both are not statistically significant after correction for multiple comparisons. Exploration analyses show a link between attention and subjective time perception after tDCS perturbation. To conclude, the results do not support the attentional gate model, but show a linkage between attention and subjective time perception in terms of similar neural circuits and their relationships under certain circumstances.

How Long Has It Been? Self-Construal and Subjective Time Perception.

Do people with independent and interdependent self-construals perceive the amount of time that has passed differently? Results from four experiments (one preregistered) and three supplementary ones reveal that an independent (vs. interdependent) self-construal elongates time perception by making individuals feel that more time has passed than in reality. We find evidence that this is likely because an independent self-construal increases arousal that affects one's "internal clock," which determines the subjective passage of time. We find this effect with externally valid and practical measures, such as by measuring how long an online video feels, how long loading a webpage feels, and how long waiting in a line feels. Our research adds to an understanding of the consequences of self-construal for one of human beings' most important judgments-time. We discuss the theoretical and practical considerations of our results as well as research limitations in closing.

The case of muddled units in temporal discounting.

While parameters are crucial components of cognitive models, relatively little importance has been given to their units. We show that this has lead to some parameters to be contaminated, introducing an artifactual correlation between them. We also show that this has led to the illegal comparison of parameters with different units of measurement - this may invalidate parameter comparisons across participants, conditions, groups, or studies. We demonstrate that this problem affects two related models: Stevens' power law and Rachlin's delay discounting model. We show that it may even affect models which superficially avoid the incompatible units problem, such as hyperbolic discounting. We present simulation results to demonstrate the extent of the issues caused by the muddled units problem. We offer solutions in order to avoid the problem in the future or to aid in re-interpreting existing datasets.