Stimulus-response compatibility with pure and mixed mappings in a flight task environment

Effectiveness of Lateral Auditory Collision Warnings: Should Warnings Be Toward Danger or Toward Safety?

OBJECTIVE

The present study investigated the design of spatially oriented auditory collision-warning signals to facilitate drivers' responses to potential collisions.

BACKGROUND

Prior studies on collision warnings have mostly focused on manual driving. It is necessary to examine the design of collision warnings for safe takeover actions in semi-autonomous driving.

METHOD

In a video-based semi-autonomous driving scenario, participants responded to pedestrians walking across the road, with a warning tone presented in either the avoidance direction or the collision direction. The time interval between the warning tone and the potential collision was also manipulated. In Experiment 1, pedestrians always started walking from one side of the road to the other side. In Experiment 2, pedestrians appeared in the middle of the road and walked toward either side of the road.

RESULTS

In Experiment 1, drivers reacted to the pedestrian faster with collision-direction warnings than with avoidance-direction warnings. In Experiment 2, the difference between the two warning directions became nonsignificant. In both experiments, shorter time intervals to potential collisions resulted in faster reactions but did not influence the effect of warning direction.

CONCLUSION

The collision-direction warnings were advantageous over the avoidance-direction warnings only when they occurred at the same lateral location as the pedestrian, indicating that this advantage was due to the capture of attention by the auditory warning signals.

APPLICATION

The present results indicate that drivers would benefit most when warnings occur at the side of potential collision objects rather than the direction of a desirable action during semi-autonomous driving.

Seeing through the cat's eyes: evidence of a spontaneous perspective taking process using a non-human avatar

In many daily face-to-face interactions, people are able to take the perspective of others, for example, coding right and left based on point-of-view of others. In the present study, we investigated whether observers are able to take the perspective of a non-human figure such as a cat, observing the same effects obtained with human or robot avatars. In both experiments, we used a centrally presented stimulus (i.e. a cat), with its tail lateralized to the left or to the right. Participants had to respond to the side of the tail with a lateralized keypress. In Experiment 1 (spatial perspective taking task), participants were required to explicitly adopt the cat's perspective to respond, whereas in Experiment 2 (SR compatibility task), this was not explicitly required. In both experiments, faster RTs are obtained when the cat is presented back, with a greater difference between front and back views when the tail is on the right; furthermore, there is no temporal modulation of the back-front effect. These common results between the two experiments are interpreted on the basis of the spatial perspective taking processes, elicited voluntarily (Experiment 1) or spontaneously (Experiment 2).

Examination of a Response–Effect Compatibility Task With Continuous Mouse Movements: Free- Versus Forced-Choice Tasks and Sequential Modulations

According to ideomotor theory, we select actions by recalling and anticipating their sensory consequences, that is, their action effects. Compelling evidence for this theory comes from response–effect compatibility (REC) experiments, in which a response produces an effect with which it is either compatible or incompatible. For example, pressing a left/right response key is faster if it is predictably followed by an action effect on the same, compatible side compared with the other, incompatible side, even though the effect itself appears only after response time is measured. Recent studies investigated this effect with continuous responses (i.e., computer mouse movements) and reported an REC effect in a forced-choice but not in a free-choice task. From the keypressing literature, the opposite result pattern or no differences would have been expected. To clarify this issue, we report 3 experiments with mouse movement responses. Experiment 1 used a simpler scenario than in prior studies and found a similar result: The REC effect was evident in a forced- but not in a free-choice task. Also, sequential modulations of the REC effect were exploratorily analyzed and replicated with higher power in Experiment 2. However, Experiment 3 demonstrated that at least part of the REC effect with mouse movements can be attributed to stimulus–response compatibility (SRC), with a much smaller compatibility effect evident with a procedure for which SRC was reduced. We conclude that a sequentially modulated compatibility effect can be observed with mouse movements, but previous studies may have underestimated the contribution from SRC. The results are also discussed in terms of why the compatibility effect was observed in forced- but not free-choice tasks with mouse movement responses.

Visual working memory load does not eliminate visuomotor repetition effects

When we respond to a stimulus, our ability to quickly execute this response depends on how combinations of stimulus and response features match to previous combinations of stimulus and response features. Some kind of memory representations must be underlying these visuomotor repetition effects. In this paper, we tested the hypothesis that visual working memory stores the stimulus information that gives rise to these effects. Participants discriminated the colors of successive stimuli while holding either three locations or colors in visual working memory. If visual working memory maintains the information about a previous event that leads to visuomotor repetition effects, then occupying working memory with colors or locations should selectively disrupt color-response and location-response repetition effects. The results of two experiments showed that neither color nor spatial memory load eliminated visuomotor repetition effects. Since working memory load did not disrupt repetition effects, it is unlikely that visual working memory resources are used to store the information that underlies visuomotor repetitions effects. Instead, these results are consistent with the view that visuomotor repetition effects stem from automatic long-term memory retrieval, but can also be accommodated by supposing separate buffers for visual working memory and response selection.

Flowers and spiders in spatial stimulus-response compatibility: does affective valence influence selection of task-sets or selection of responses?

The present study examined the effect of stimulus valence on two levels of selection in the cognitive system, selection of a task-set and selection of a response. In the first experiment, participants performed a spatial compatibility task (pressing left and right keys according to the locations of stimuli) in which stimulus-response mappings were determined by stimulus valence. There was a standard spatial stimulus-response compatibility (SRC) effect for positive stimuli (flowers) and a reversed SRC effect for negative stimuli (spiders), but the same data could be interpreted as showing faster responses when positive and negative stimuli were assigned to compatible and incompatible mappings, respectively, than when the assignment was opposite. Experiment 2 disentangled these interpretations, showing that valence did not influence a spatial SRC effect (Simon effect) when task-set retrieval was unnecessary. Experiments 3 and 4 replaced keypress responses with joystick deflections that afforded approach/avoidance action coding. Stimulus valence modulated the Simon effect (but did not reverse it) when the valence was task-relevant (Experiment 3) as well as when it was task-irrelevant (Experiment 4). Therefore, stimulus valence influences task-set selection and response selection, but the influence on the latter is limited to conditions where responses afford approach/avoidance action coding.

Tracking and discrete dual task performance with different spatial stimulus-response mappings

The effect of spatial compatibility on dual-task performance for various display-control configurations was studied using a tracking task and a discrete four-choice response task. A total of 36 participants took part in this study, and they were asked to perform the primary tracking task while at the same time to respond to an occasional signal. Different levels of compatibility between the stimuli and responses of the discrete response task were found to lead to different degrees of influence on the tracking task. However, degradation of performance was observed for both tasks, which was probably due to resource competition for the visual and spatial resources required for simultaneous task operation and required for bimanual responses. No right-left prevalence effect for the spatial compatibility task was observed in this study, implying that the use of unimanual two-finger responses may not provide the right conditions for a significant effect in the horizontal right-left dimension.

PRACTITIONER SUMMARY

The effect of spatial compatibility in multiple display-control configurations was examined in a dual-task paradigm. The analyses of keen competition for visual and spatial resources in processing the dual tasks under different degrees of stimulus-response compatibility provide useful ergonomics design implications and recommendations for visual interfaces requiring frequent visual scanning.

Response-effect compatibility defines the natural scrolling direction

OBJECTIVE

We evaluated alternative scrolling methods on non-touch screen computer operating systems by comparing human performance in different scrolling conditions.

BACKGROUND

The scrolling directions on current operating systems are discrepant. Few researchers have investigated how scrolling method influences users performance. The response-effect (R-E) compatibility principle can be used as a theoretical guide.

METHOD

Experiments 1 and 2 involved two successive tasks (scrolling and target content judgment) to simulate how people scroll to acquire and use off-screen information. Performance in R-E compatible and incompatible conditions was compared. Experiment 3 involved a location judgment task to test the influence of target location. Experiments 4 and 5 included a scrolling effect following the location judgment task to test the sufficient role of the scrolling effect.

RESULTS

Overall, responses were facilitated when the response direction was compatible with the forthcoming display-content movement direction (an R-E compatibility effect), when the scrolling effect was task relevant or task irrelevant. A spatial stimulus-response (S-R) compatibility effect attributable to target location was also found. When the scrolling effect was present, there were both R-E and S-R components; the R-E effect was the larger of the two.

CONCLUSION

Scrolling in the direction of content movement yielded the best performance, and the scrolling effect was the main source of the R-E compatibility effect.

APPLICATION

These findings suggest that (a) the R-E compatibility principle may be used as a general design guideline for scrolling and (b) a consistent scrolling method should be available on various operating systems.

Effect of prior practice on the stimulus-response compatibility effect in a mixed mapping environment

A stimulus-response compatibility (SRC) effect is obtained when performance is better with compatible mappings than with incompatible mappings. When mappings are mixed within a task, the SRC effect is often eliminated or reversed.The present study examines how 1,600 trials with different practice tasks can affect the response selection process in these mixed mapping environments. Participants were assigned to one of three practice groups: mixed mapping, pure compatible mapping, and pure incompatible mapping. Subsequently, all participants performed an experimental session in which compatible and incompatible trials were mixed.The SRC effect was eliminated in the experimental mixed mapping session, regardless of practice condition. The results suggest that practice does not change the need to suppress the direct response selection route in a mixed mapping task. However, reaction time distributions and sequential analyses were modulated by practice condition, which indicates that the new associations acquired during practice may activate new routes that interact with preexisting ones.

On the Persistence of Tool-Based Compatibility Effects

Using tools, such as simple levers, makes specific demands on the motor system. Two related performance decrements have been reported: The costs that arise when required tool movements and movements of the operating hand are spatially incompatible (hand-tool compatibility), and the costs that arise when relevant stimuli and tool movements are spatially incompatible (stimulus-tool compatibility). We performed two experiments to test the boundary conditions of both effects. Experiment 1 revealed a strong hand-tool compatibility effect despite visual occlusion of the hand and instructions to ignore hand movements. Experiment 2 revealed influences of stimulus-tool compatibility despite instructions to ignore the tool and to pay attention to the operating hand alone. These results suggest that lever movements of the type studied here become automatically represented and constrain motor performance.

Influence of bias on visuospatial and verbal compatibility effects in mixed-mapping environments

The advantage for the compatible mapping of physical locations or arrows to keypresses is reduced when trials with compatible and incompatible mappings are mixed, whereas the advantage is increased for location words. We evaluated explanations of these mixing effects by varying the proportions of compatible and incompatible trials for groups performing with each stimulus mode. The mappings were compatible on 75%, 50%, and 25% of the trials, respectively, for compatibly biased, unbiased, and incompatibly biased conditions. For locations and arrows, compatible bias increased the SRC effect, and incompatible bias reduced the effect; for location words, the incompatible bias was stronger than the compatible one. Reaction time distributions showed that, with locations and arrows, initial activation toward either the compatible (unbiased condition) or the predominant (biased conditions) response was transient. With words, activation of the corresponding response increased across the distribution, regardless of bias condition. The influence of bias on the SRC effects was relatively independent of the mixing and sequential effects, and was different for words than for nonwords. These results are consistent with the view that visuospatial stimuli produce transient activation of the corresponding or predominant response, whereas location words produce phonological activation, required for word identification, that persists.

Action control while seeing mirror images of one's own movements: Effects of perspective on spatial compatibility

It is examined whether and how the perspective of seeing one's own movements exerted an influence on action control. Such change in the perspective challenges an information processor, as she or he has to handle successfully the discrepancies between the tactile/proprioceptive feedback and the visual feedback on a projection screen. In the experiments participants responded to visual stimuli, but saw their responses either from the top or with an x-axis reflection, a y-axis reflection, or a reflection about both axes. The results showed that a change in perspective did not impair performance as long as the left–right relations corresponded with the body space (e.g., with visual feedback reflected about the x-axis). By contrast, performance was drastically reduced when visual feedback was reflected about the y-axis or about both axes, so that performed left-side (right-side) movements were seen as right-side (left-side) movements. It is concluded that an actor preferably relies on the information of the visual system, but refers to the tactile/proprioceptive information when it facilitates the task demands.

Instance-based Learning Models of Training

The IBL theory (IBLT) was developed to demonstrate the cognitive processes and mechanisms involved in dynamic decision making. IBLT has been implemented in several ACT-R cognitive models that showcase a variety of training effects and generate predictions resulting from several training manipulations. Particular implementations of IBLT-based models of training may depend on the task representation, the cues that are important for that task, and the particular decision actions involved, but the cognitive processes followed are generic. Here, we summarize different cognitive models for a diverse set of tasks relying on the IBLT. We also present an initial implementation of an IBL modeling tool that will help researchers develop their own IBL models without a need to program in ACT-R.

Stimulus–response compatibility for mixed mappings and tasks with unique responses

For two stimulus locations mapped to two keypresses, reaction time is shorter when the mapping is compatible than when it is not (the stimulus–response compatibility, SRC, effect). A similar result, called the Simon effect, occurs when stimulus location is irrelevant, and colour is relevant. When compatibly mapped trials are intermixed with incompatibly mapped trials or Simon task trials, the compatibility effect is eliminated, and the Simon effect is influenced by the location mapping. In five experiments, we examined whether similar mixing effects occur when the two spatial mappings or location-relevant and location-irrelevant tasks use distinct keypresses on the left and right hands. Mixing had considerably less influence on the SRC and Simon effects than it does when the intermixed trial types or tasks share the same responses, even though response time was lengthened to a similar extent. Mixing two tasks for which stimulus location was irrelevant yielded no within-task Simon effect, but the effect was also absent when four stimuli were assigned to two responses on a single hand. The relative lack of influence of mixing on the SRC and Simon effects when the tasks have unique responses implies that suppression of direct activation of the corresponding response occurs primarily when the tasks share responses.

Task-defined associations are mode specific for selection of relevant dimension but mode independent for selection of location mapping

When compatible and incompatible mappings of a location-relevant task are mixed, or a location-relevant task is mixed with a task for which stimulus location is irrelevant, the benefit of the compatible mapping is eliminated for physical locations and enhanced for location words. Two experiments examined the influence of presenting the location information for the mixed conditions in different stimulus modes (physical location or word). Experiment 1 showed that the effects of mixing location-relevant and location-irrelevant tasks on the spatial compatibility and Simon effects are reduced when the location information is presented in different modes for the two tasks. Experiment 2 showed, in contrast, that the mode distinction had little influence on the effects of mixed compatible and incompatible mappings for location-relevant tasks: The compatibility effect was eliminated for physical locations and enhanced for words, as when there is no mode distinction. Thus, when location is relevant for one task and colour for the other, the task-defined associations of locations to responses are mode specific, but when location is relevant for both tasks, the associations are mode independent.