Tomat, Miriam

Public attitude toward Unmanned Aerial Vehicles (UAVs) has been extensively researched, frequently using surveys or experimental settings involving sound/noise. In this study, we present an experiment using visual stimuli, exploring not only the acceptance of UAVs as such but also of their interactions with different environments. The stimuli were pictures of quadcopters, either white or orange, with medical or commercial markings. For comparison, pictures of helicopters with the same four variations and a goose were also used. These pictures were superimposed over three types of backgrounds: urban, industrial, and rural. Twenty-four student participants took part in this study, each responding to 81 stimuli with Likert scale ratings for the acceptance and beauty of the stimuli after responding to objects that were used as a manipulation check. Reaction times for all responses were recorded. Afterward, participants completed a survey designed to identify the reasons for their judgments regarding acceptance. Our results deliver a complex view of the acceptance of UAVs. For example, the usage of the UAV had the largest impact on acceptance, with medical usage having the highest acceptance rating. Commercial usage was more accepted in industrial areas, and UAVs were more accepted than helicopters. The survey showed a heterogeneous variety and relevance of reasons for the acceptance ratings. On average, usefulness, traffic relief, reduction of privacy, and acceptance by society were indicated as the most relevant factors affecting the acceptance ratings. In general, our study suggests that the less considered visual factors of drones (salience in our study) can be expected to influence the acceptance of UAVs in addition to the noise factor. Most importantly, the physical characteristics of UAVs alone are insufficient to predict their acceptance. The purposes for which UAVs are used (that might be visually recognizable) and the environment in which they are operated play an important role in shaping public attitudes towards this new technology.

Performance in task switching experiments is worse when the current stimulus is associated with different responses in the two tasks (i.e., incongruent condition) than when it is associated with the same response (i.e., congruent condition). This congruency effect reflects some sort of application of the irrelevant task's stimulus-response translation rules. Manipulating the recency and the proportion of congruent and incongruent trials results in a modulation of the congruency effect (i.e., Congruency Sequence Effect, CSE, and Proportion Congruency Effect, PCE, respectively), suggesting attentional adjustment of processing weights. Here, we investigated the impact of task switching practice on the congruency effect and the modulation thereof by (a) re-analyzing the data of a task switching experiment involving six consecutive sessions and (b) conducting a novel four-session experiment in which the proportions of congruent and incongruent trials were manipulated. Although practice appeared to reduce the reaction times overall and the task switch costs (i.e., slower reaction times after task switches than after task repetitions) to an asymptotic level, the congruency effect as well as its modulations remained remarkably constant. These findings thus do not provide evidence that conflict effects between tasks and attentional adjustment are affected by task switching practice.

Interference evoked by a distractor presented prior to a target stimulus is reduced when the distractor-target SOA is increased, suggesting inhibition of distractor-related activation. Distractor processing is also assumed to be (strategically) adjusted to the proportions of congruent and incongruent target-distractor combinations, yielding a larger distractor interference effect when the proportion of congruent trials is higher (i.e., Proportion Congruent Effect, PCE). To explore the interplay of proportion congruent-based processing adjustment and the time course of distractor-related activation we varied the proportions of congruent and incongruent trials as well as the distractor-target SOA. To control for item-specific priming we kept distractor-related contingencies (i.e., frequency of individual distractor-target conjunctions) constant for a subset of the stimuli (and used a different subset to manipulate the proportions of congruent and incongruent trials). A PCE occurred, even for the subset of stimuli associated with constant distractor-related contingencies, thus ruling out item-specific contingency learning. Distractor interference was reduced when the SOA was increased, but this reduction did not differ between the proportion congruent conditions, as confirmed by a Bayesian analysis. Our results are consistent with independent processes pertaining to usage of distractor information for biasing response selection and distractor inhibition during the SOA. Alternative interpretations of the independent effects of the PC manipulation and the distractor-target SOA are discussed.

The Congruency Sequence Effect (CSE) denotes the common finding that distractor–target Congruency Effects are reduced after incongruent compared to after congruent trials. Although the CSE is widely attributed to attentional adjustment (i.e., increasing or decreasing the bias in attentional weights regarding processing the target or distractor), unequivocal evidence for this assumption is missing. To investigate the CSE and attentional adjustment we used a temporal flanker task and intermixed a “temporal search task”, in which a target stimulus occurred randomly at one of two temporal positions, corresponding to the temporal positions of the target and the distractor occurrence in the temporal flanker task. We observed a CSE that could not be explained in terms of feature sequences, distractor-related contingencies, or a strategy of reversed distractor–response priming after incongruent trials. Furthermore, following a temporal search task trial, the Congruency Effect was larger when the search target occurred on the first than on the second temporal position, demonstrating that a reduced attentional bias towards the second temporal position increased interference from a distractor presented on the first temporal position. This supports a crucial assumption of the attentional adjustment account of the CSE. Performance in the temporal search task, however, provided no evidence for attentional adjustment. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.