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Rationale: Peak velocities of saccadic eye movements are reduced after benzodiazepine administration. Even though this is an established effect, past research has only examined it in horizontal prosaccade tasks., Objectives: The spectrum of saccadic eye movements, however, is much larger. Therefore, we aimed to make a first attempt at filling this research gap by testing benzodiazepine effects on saccades under different experimental task conditions., Methods: 1 mg lorazepam or placebo was administered (within-subjects, double-blind, in randomised order) to n = 30 healthy adults. Participants performed an extended version of the prosaccade task, including vertical saccade directions and different stimulus eccentricities, as well as a free viewing task., Results: Results from the prosaccade task confirmed established effects of benzodiazepines as well as saccade direction on saccadic parameters but additionally showed that the drug effect on peak velocity was independent of saccade direction. Remarkably, in the free viewing task peak velocities as well as other saccade parameters were unaffected by lorazepam. Furthermore, exploration patterns during free viewing did not change under lorazepam., Conclusions: Overall, our findings further consolidate the peak velocity of prosaccades as a biomarker of sedation. Additionally, we suggest that sedative effects of low doses of benzodiazepines may be compensated in tasks that more closely resemble natural eye movement behaviour, possibly due to the lack of time constraints or via neurophysiological processes related to volition., (© 2024. The Author(s).)

When free-viewing scenes, participants tend to preferentially fixate social elements (e.g., people). In the present study, we tested whether this bias would be disrupted by increasing the demands of a secondary dual-task: holding a set of (one or six) spatial locations in memory, presented either simultaneously or sequentially. Following a retention interval, participants judged whether a test location was present in the to-be-remembered stimuli. During the retention interval participants free-viewed scenes containing a social element (a person) and a non-social element (an object) that served as regions of interest. In order to assess the impact of physical salience, the non-social element was presented in both an unaltered baseline version, and in a version where its salience was artificially increased. The results showed that the preference to look at social elements decreased when the demands of the spatial memory task were increased from one to six locations, regardless of presentation mode (simultaneous or sequential). The high-load condition also resulted in more central fixations and reduced exploration of the scene. The results indicate that the social prioritisation effect, and scene viewing more generally, can be affected by a concurrent memory load., (© 2023. The Author(s).)

Linguistic syntax has often been claimed as uniquely complex due to features like anaphoric relations and distance dependencies. However, visual narratives of sequential images, like those in comics, have been argued to use sequencing mechanisms analogous to those in language. These narrative structures include "refiner" panels that "zoom in" on the contents of another panel. Similar to anaphora in language, refiners indexically connect inexplicit referential information in one unit (refiner, pronoun) to a more informative "antecedent" elsewhere in the discourse. Also like in language, refiners can follow their antecedents (anaphoric) or precede them (cataphoric), along with having either proximal or distant connections. We here explore the constraints on visual narrative refiners created by modulating these features of order and distance. Experiment 1 examined participants' preferences for where refiners are placed in a sequence using a force-choice test, which revealed that refiners are preferred to follow their antecedents and have proximal distances from them. Experiment 2 then showed that distance dependencies lead to slower self-paced viewing times. Finally, measurements of event-related brain potentials (ERPs) in Experiment 3 revealed that these patterns evoke similar brain responses as referential dependencies in language (i.e., N400, LAN, Nref). Across all three studies, the constraints and (neuro)cognitive responses to refiners parallel those shown to anaphora in language, suggesting domain-general constraints on the sequencing of referential dependencies., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)