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Kamienkowski, J. E.

Publications and source records attributed to Kamienkowski, J. E..

3 recordsLinked to original sources

Investigating the effects of contextual information, visual working memory, and inhibitory control in hybrid visual search

In real-life scenarios, individuals frequently engage in tasks that involve searching for one of various items stored in memory. This combined process of visual search and memory search is known as hybrid search. To date, most hybrid search studies have been restricted to average observers looking for previously well-memorized targets in blank backgrounds. Here we investigated the effects of context and the role of memory in hybrid search by modifying the tasks memorization phase to occur in all-new single trials. Additionally, we aimed to assess how individual differences in visual working memory capacity and inhibitory control influence performance during hybrid search. In an online experiment, 110 participants searched for potential targets in images with and without context. A change detection and go/no-go task were also performed to measure working memory capacity and inhibitory control, respectively. We show that, in target present trials, the main hallmarks of hybrid search remain present, with a linear relationship between reaction time and visual set size, and a logarithmic relationship between reaction time and memory set size. Context affected search efficiency in different ways. In target-absent trials we found large differences between context-present and absent conditions, suggesting participants adoption of adaptive strategies. Finally, working memory capacity did not predict most search performance measures. Inhibitory control, when relationships were significant, could account for only a small portion of the variability in the data. This study provides insights into the effects of context and individual differences on search efficiency and termination.

animal behavior and cognition↗

Web-based eye-tracking for remote cognitive assessments: The anti-saccade task as a case study

Over the last years, several developments of remote webcam-based eye tracking (ET) prototypes have emerged, testing their feasibility and potential for web-based experiments. This growing interest is mainly explained by the possibility to perform tasks remotely, which allows the study of larger and hard-to-reach populations and potential applications in telemedicine. Nevertheless, a decrease in the quality of the camera and a noisier environment bring new implementation challenges. In this study, we present a new prototype of remote webcam-based ET. First, we introduced improvements to the state-of-the-art remote ET prototypes for cognitive and clinical tasks, e.g. without the necessity of constant mouse interactions. Second, we assessed its spatiotemporal resolution and its reliability within an experiment. Third, we ran a classical experiment, the anti-saccade task, to assess its functionality and limitations. This cognitive test compares horizontal eye movements toward (pro-saccades) or away from (anti-saccades) a target, as a measure of inhibitory control. Our results replicated previous findings obtained with high-quality laboratory ETs. Briefly, higher error rates in anti-saccades compared to pro-saccades were observed, and incorrect responses presented faster reaction times. Our web-ET prototype showed a stable calibration over time and performed well in a classic cognitive experiment. Finally, we discussed the potential of this prototype for clinical applications and its limitations for experimental use.

neuroscience↗

Active search signatures in a free-viewing task exploiting concurrent EEG and eye movements recordings

Tasks we often perform in our everyday lives, such as reading or looking for a friend in the crowd, are seemingly straightforward but they actually require the orchestrated activity of several cognitive processes. Free-viewing visual search requires a plan to move our gaze on the different items, identifying them, and deciding on whether to continue with the search. Little is known about the electrophysiological signatures of these processes in free-viewing since there are technical challenges associated with eye movement artifacts. Here we aimed to study how category information, as well as ecologically-relevant variables such as the task performed, influence brain activity in a free-viewing paradigm. Participants were asked to observe/search from an array of faces and objects embedded in random noise. We concurrently recorded EEG and eye movements and applied a deconvolution analysis approach to estimate the contribution of the different elements embedded in the task. Consistent with classical fixed-gaze experiments and a handful of free-viewing studies, we found a robust categorical effect around 150 ms in occipital and occipitotemporal electrodes. We also report a task effect, more negative in posterior central electrodes in visual search compared to exploration, starting at around 80 ms. We also found significant effects of trial progression, and an interaction with the task effect. Overall, these results generalise the characterisation of early visual face processing to a wider range of experiments and show how a suitable analysis approach allows to discern among multiple neural contributions to the signal, preserving key attributes of real-world tasks.

neuroscience↗