Dustin P. Calvillo

Animacy, perceptual load, and inattentional blindness

Inattentional blindness is the failure to notice unexpected objects in a visual scene while engaging in an attention-demanding task. We examined the effects of animacy and perceptual load on inattentional blindness. Participants searched for a category exemplar under low or high perceptual load. On the last trial, the participants were exposed to an unexpected object that was either animate or inanimate. Unexpected objects were detected more frequently when they were animate rather than inanimate, and more frequently with low than with high perceptual loads. We also measured working memory capacity and found that it predicted the detection of unexpected objects, but only with high perceptual loads. The results are consistent with the animate-monitoring hypothesis, which suggests that animate objects capture attention because of the importance of the detection of animate objects in ancestral hunter–gatherer environments.

The misinformation effect is unrelated to the DRM effect with and without a DRM warning

The misinformation and Deese–Roediger–McDermott (DRM) paradigms are used to study forms of false memories. Despite the abundance of research using these two paradigms, few studies have examined the relationship between the errors that arise from them. In the present study, 160 participants completed a misinformation task and two DRM tasks, receiving a warning about the effect before the second DRM task. Participants demonstrated misinformation and DRM effects (with and without the warning), but susceptibility to these forms of false memory were not significantly related across individuals. The DRM warning reduced the DRM effect, and signal detection analysis revealed that the DRM warning reduced a liberal response bias in this task. Sensitivity and response bias in both DRM tasks were not significantly related to these measures in the misinformation task. These findings suggest that these two forms of false memories are not interchangeable and they appear to be the result of different cognitive processes.

Animate Objects are Detected More Frequently than Inanimate Objects in Inattentional Blindness Tasks Independently of Threat

ABSTRACT Inattentional blindness occurs when individuals are engaged in an attention-demanding task and fail to detect unexpected objects in their visual field. Two experiments examined whether certain unexpected objects are more easily detected than others. The unexpected objects were animate and threatening (e.g., snake), animate and nonthreatening (e.g., bird), inanimate and threatening (e.g., gun), or inanimate and nonthreatening (e.g., bed). Three hypotheses were tested: the snake detection hypothesis (snakes will be detected more frequently than all other objects), the animate monitoring hypothesis (animate objects will be detected more frequently than inanimate objects), and the threat superiority hypothesis (threatening objects will be detected more frequently than nonthreatening objects). Only the animate monitoring hypothesis was supported in both experiments. These results suggest that animate objects capture attention in the absence of task-relevant goals and that snakes do not show an advantage over other animate objects in inattentional blindness tasks.

Surprise Influences Hindsight-Foresight Differences in Temporal Judgments of Animated Automobile Accidents

The hindsight bias occurs when people view an outcome as more foreseeable than it actually was. The role of an outcome’s initial surprise in the hindsight bias was examined using animations of automobile accidents. Twenty-six participants rated the initial surprise of accidents’ occurring in eight animations. An additional 84 participants viewed these animations in one of two conditions: Half stopped the animations when they were certain an accident would occur (i.e., in foresight), and the other half watched the entire animations first and then stopped the animations when they thought that a naïve viewer would be certain that an accident would occur (i.e., in hindsight). When the accidents were low in initial surprise, there were no foresight–hindsight differences; when initial surprise was medium, there was a hindsight bias; and when initial surprise was high, there was a reversed hindsight bias. The results are consistent with a sense-making model of hindsight bias.

Evolutionary Relevance Facilitates Visual Information Processing

Visual search of the environment is a fundamental human behavior that perceptual load affects powerfully. Previously investigated means for overcoming the inhibitions of high perceptual load, however, generalize poorly to real-world human behavior. We hypothesized that humans would process evolutionarily relevant stimuli more efficiently than evolutionarily novel stimuli, and evolutionary relevance would mitigate the repercussions of high perceptual load during visual search. Animacy is a significant component to evolutionary relevance of visual stimuli because perceiving animate entities is time-sensitive in ways that pose significant evolutionary consequences. Participants completing a visual search task located evolutionarily relevant and animate objects fastest and with the least impact of high perceptual load. Evolutionarily novel and inanimate objects were located slowest and with the highest impact of perceptual load. Evolutionary relevance may importantly affect everyday visual information processing.

The role of similarity in deductive categorical inference

The category inclusion rule specifies that categories inherit the properties of their superordinates. For example, given thatall metals are pentavalent, it can be concluded thatall iron is pentavalent. Sloman (1998) showed that people do not fully endorse conclusions that follow from the category inclusion rule. He claims that people rely on the similarity between the premise and the conclusion categories (metals andiron), rather than applying the category inclusion rule. By allowing reasoners to rate their certainty for category relations (e.g.,iron is metal), as well as for conclusions, the present study shows that similarity has only an indirect effect on the certainty of conclusions: Reasoners are more certain that similar categories have a category inclusion relation, and this in turn affects the certainty of conclusions based on this relation.

Incubation Provides Relief from Artificial Fixation in Problem Solving

An incubation effect occurs when taking a break from a problem helps solvers arrive at the correct solution more often than working on it continuously. The forgetting-fixation account, a popular explanation of how incubation works, posits that a break from a problem allows the solver to forget the incorrect path to the solution and finally access the correct path. This study tested the forgetting-fixation account using a trial-by-trial method on a sample of 152 native English speakers who were asked to solve 12 remote associate tests (RATs). During the first attempt, participants in the fixation condition were presented with misleading clues, and those in the no-fixation condition were not. At the completion of the first attempt for each RAT, half of the fixation and half of the no-fixation participants read an article for 2 min before attempting to solve the RAT for the second time, but the other halves worked on each RAT continuously. As predicted by the forgetting-fixation account, only in the fixation condition did participants who read an article perform better than those who worked on them continuously. Moreover, fixated participants performed better than nonfixated participants, and this differential effect was only evident in the incubation condition.

Individual Differences in Susceptibility to Misinformation Effects and Hindsight Bias

ABSTRACT. The present study examined individual differences in susceptibility to two similar forms of memory distortion: the misinformation effect and hindsight bias. The misinformation effect occurs when individuals witness an event, are provided with misinformation, and recall the original event as containing elements of the misinformation. Hindsight bias occurs when individuals make judgments, are provided with feedback, and recall their original judgments as being more similar to the feedback than they actually were. Seventy-five participants completed a misinformation task, a hindsight bias task, and several individual difference measures related to memory distortions. Working memory capacity was negatively correlated with the misinformation effect and hindsight bias, and the misinformation effect and hindsight bias were negatively correlated with one another. Although the misinformation effect and hindsight bias are measured with similar designs, and both are predicted by working memory capacity, the negative correlation between them suggests these phenomena result from somewhat different processes.

A brief mindfulness induction after encoding decreases false recognition in the Deese-Roediger-McDermott paradigm.

Mindfulness is the mental state of awareness of what one is experiencing at the present moment by acknowledging one’s thoughts without judgment. Studies have shown that mindfulness training is beneficial to various cognitive processes, including attention and memory, but that it may increase susceptibility to false memories in the Deese–Roediger–McDermott (DRM) paradigm. These studies induced mindfulness before the encoding of DRM word lists. The present study extended previous research by manipulating the placement of a mindfulness induction. Participants (N = 228) received either a mindfulness induction before encoding DRM words, after encoding, or they received no induction. Participants who received the induction after encoding falsely recognized fewer critical lures and were less liberally biased in their responses than participants in the other two groups. There were no significant differences in true recognition between the groups. These findings suggest that a brief mindfulness induction after encoding, but before retrieval, reduces false memories in the DRM paradigm by making one’s response decision criterion more conservative. Limitations and recommendations for future research on the effects of mindfulness training on false memories are discussed.

Imagining Experiencing an Event in the Future Inflates Certainty That It Occurred in the Past

Imagination inflation occurs when participants increase their certainty that they have experienced an event after they imagine the event occurring. Two experiments (with a total of 291 participants) examined the effects of imagining events in the future on participants’ certainty they had experienced those events in the past. Participants rated their certainty in having experienced events and then imagined experiencing some of those events either in the future or in the past. One or two weeks later, participants completed certainty ratings a second time and completed some individual difference measures. In both imagination conditions (future and past), certainty ratings increased more for imagined events than for control events. Autobiographical memory specificity and self-concept clarity did not significantly predict this effect. These findings suggest that imagining events in the future makes people more certain that they have happened in the past.