I have spent two months (January-March 2017) in the group of Joan López-Moliner in Institut de Neruociències and Departament de Cognició i Desenvolupament, Universitat de Barcelona. The main purpose of my stay was to conduct an experiment, bringing together time perception and confidence research from the Paris lab and sensory-motor approach adopted in Barcelona.
The study conducted during my secondment aimed at investigating how humans trade off different sources of uncertainty for the timing of an action. Furthermore, we asked how participants estimated confidence about their performance. We recorded participants’ movement on a graphic tablet, while they were synchronizing the arm movement with predictable temporal sequence. After each trial, we asked them to estimate confidence in their performance.
Photo of the experimental setup. A. Participants were moving their arm on a graphic tablet to reach the target in front of them. We recorded their hand position during the trial and confidence estimations. B. Schematic representation of stimulus sequence and hand position in one trial.
We found a preference for delaying onset of a movement and minimizing movement duration. Also, we observed that the greater the deviation from the mean onset time, the less confident the participants were about their performance, while movement duration contributed less to confidence judgments. Altogether, our results suggest that people have only limited insight into movement time and variability.
Average reaction time and movement duration distribution. (A) Frequency of reaction time and movement duration. (B) Absolute temporal error as a function of centered reaction time and movement duration. Large deviations from reaction time or movement duration lead to large temporal errors. (C) Average confidence estimation as a function of reaction time and movement duration. Confidence was related to deviations in reaction time, but not movement duration.
Importantly, human time perception and confidence about performance have rarely been investigated in complex sensory-motor tasks. Therefore, integrating expertise from the two labs enabled us to ask and pursue important questions from a novel perspective. Finally, the opportunity to spend two months in another lab helped me broaden my perspective of different scientific and individual approaches to the field.