Do rufous hummingbirds (<Emphasis Type="Italic">Selasphorus rufus</Emphasis>) use visual beacons?

Animals are often assumed to use highly conspicuous features of a goal to head directly to that goal (‘beaconing’). In the field it is generally assumed that flowers serve as beacons to guide pollinators. Artificial hummingbird feeders are coloured red to serve a similar function. However, anecdotal reports suggest that hummingbirds return to feeder locations in the absence of the feeder (and thus the beacon). Here we test these reports for the first time in the field, using the natural territories of hummingbirds and manipulating flowers on a scale that is ecologically relevant to the birds. We compared the predictions from two distinct hypotheses as to how hummingbirds might use the visual features of rewards: the distant beacon hypothesis and the local cue hypothesis. In two field experiments, we found no evidence that rufous hummingbirds used a distant visual beacon to guide them to a rewarded location. In no case did birds abandon their approach to the goal location from a distance; rather they demonstrated remarkable accuracy of navigation by approaching to within about 70 cm of a rewarded flower’s original location. Proximity varied depending on the size of the training flower: birds flew closer to a previously rewarded location if it had been previously signalled with a small beacon. Additionally, when provided with a beacon at a new location, birds did not fly directly to the new beacon. Taken together, we believe these data demonstrate that these hummingbirds depend little on visual characteristics to beacon to rewarded locations, but rather that they encode surrounding landmarks in order to reach the goal and then use the visual features of the goal as confirmation that they have arrived at the correct location.     

The time course of configural change detection for novel 3-D objects

The present study investigated the time course of visual information processing that is responsible for successful object change detection involving the configuration and shape of 3-D novel object parts. Using a one-shot change detection task, we manipulated stimulus and interstimulus mask durations (40&#x2014;500 msec). Experiments 1A and 1B showed no change detection advantage for configuration at very short (40-msec) stimulus durations, but the configural advantage did emerge with durations between 80 and 160 msec. In Experiment 2, we showed that, at shorter stimulus durations, the number of parts changing was the best predictor of change detection performance. Finally, in Experiment 3, with a stimulus duration of 160 msec, configuration change detection was found to be highly accurate for each of the mask durations tested, suggesting a fast processing speed for this kind of change information. However, switch and shape change detection reached peak levels of accuracy only when mask durations were increased to 160 and 320 msec, respectively. We conclude that, with very short stimulus exposures, successful object change detection depends primarily on quantitative measures of change. However, with longer stimulus exposures, the qualitative nature of the change becomes progressively more important, resulting in the well-known configural advantage for change detection.     

Disgust as embodied moral judgment

How, and for whom, does disgust influence moral judgment? In four experiments participants made moral judgments while experiencing extraneous feelings of disgust. Disgust was induced in Experiment 1 by exposure to a bad smell, in Experiment 2 by working in a disgusting room, in Experiment 3 by recalling a physically disgusting experience, and in Experiment 4 through a video induction. In each case, the results showed that disgust can increase the severity of moral judgments relative to controls. Experiment 4 found that disgust had a different effect on moral judgment than did sadness. In addition, Experiments 2-4 showed that the role of disgust in severity of moral judgments depends on participants' sensitivity to their own bodily sensations. Taken together, these data indicate the importance-and specificity-of gut feelings in moral judgments.     

Social learning modulates the lateralization of emotional valence

Although neuropsychological studies of lateralization of emotion have emphasized valence (positive vs. negative) or type (basic vs. complex) dimensions, the interaction between the two dimensions has yet to be elucidated. The purpose of the current study was to test the hypothesis that recognition of basic emotions is processed preferentially by the right prefrontal cortex (PFC), whereas recognition of complex social emotions is processed preferentially by the left PFC. Experiment 1 assessed the ability of healthy controls and patients with right and left PFC lesions to recognize basic and complex emotions. Experiment 2 modeled the patient’s data of Experiment 1 on healthy participants under lateralized displays of the emotional stimuli. Both experiments support the Type as well as the Valence Hypotheses. However, our findings indicate that the Valence Hypothesis holds for basic but less so for complex emotions. It is suggested that, since social learning overrules the basic preference of valence in the hemispheres, the processing of complex emotions in the hemispheres is less affected by valence.     

Involuntary autobiographical memories in and outside the laboratory: How different are they from voluntary autobiographical memories?

In two studies, we compared the characteristics and retrieval times of involuntary and voluntary autobiographical memory under controlled laboratory conditions. A new laboratory task of involuntary autobiographical memories involved detecting vertical lines in a stream of stimuli with horizontal lines (an undemanding vigilance task) and recording any involuntary memories during the session. The majority of these memories were reported as being triggered by irrelevant cue phrases presented on the screen. Voluntary autobiographical memories were sampled via a standard word-cue method in Session 2. The results showed that involuntary memories were more specific and were retrieved significantly faster than voluntary memories. They were also more likely to be triggered by negative cues, whereas cue valence did not have any effect on the number of voluntary memories. Furthermore, laboratory involuntary memories did not differ from naturalistic involuntary memories recorded in a diary by the same participants (Study 2). Taken together, these results have important implications for current theories of autobiographical memory, and they open up interesting avenues for future research.     

Explaining False Uniqueness: Why We are Both Better and Worse Than Others

People see themselves as unique from others – as having better personalities and abilities, more desirable opinions, and brighter futures than almost everyone else. In the past, researchers attributed these ‘false uniqueness perceptions’ primarily to a need or desire to see oneself in the most charitable light possible (i.e., self‐enhancement). More recent findings – that oftentimes people claim to be worse off than others – call this view into question and raise the need to find explanations that can account for both positive and negative forms of uniqueness perceptions. This review describes several of the leading non‐motivated (cognitive) explanations for false uniqueness perceptions and discusses recent empirical findings that establish their role in these phenomena. The rationality of false uniqueness perceptions and the status of motivated reasoning are also briefly considered.     

Regularity of symmetry verticality guides perceptual judgments of objects

Previous research indicated that most salient, real-world objects possess natural regularities that observers commonly assume in perceptual judgments of figural orientation and interpretation. Regularities include 3-dimensionality, bilateral symmetry, and the tendency for object tops to possess more salient information than bottoms. Thus, when observers interpret randomly shaped figures, they reliably impose volume, bilateral symmetry, and top and front orientation directions, even when figures are 2-dimensional and asymmetric. We confirmed generalizability for observers to assume these regularities with stimuli that vary in complexity, and we found evidence supporting another regularity, that of symmetry verticality (symmetry about a vertical axis). Findings support use of a family of perceptual heuristics corresponding to natural regularities that constrain stimulus indeterminacy and help guide judgment of object orientation and interpretation.     

Interpersonal subtypes within generalized anxiety disorder

In this study, we addressed the heterogeneity in interpersonal problems across patients with generalized anxiety disorder (GAD). We assessed interpersonal problems by the Inventory of Interpersonal Problems (IIP-C; Horowitz, Alden, Wiggins, & Pincus, 2000) in a sample of 78 GAD patients. We used IIP-C profiles describing interpersonal characteristics of the total GAD sample as well as clustered GAD interpersonal subtypes. Although the overall sample was located in the friendly submissive quadrant of the circumplex model, this was true only for the Exploitable cluster, which includes more than 50% of the patients. Importantly, clusters of GAD patients with other locations reporting predominantly Cold, Nonassertive, or Intrusive interpersonal problems were also identified. The 4 clusters did not differ in terms of gender, comorbid disorders, or the severity of depression or anxiety. Thus, the assessment of interpersonal problems provides additional diagnostic information covering the heterogeneity of GAD patients. This information could be used for differential indication and individual case formulation in GAD.     

Missed opportunity for creating value in negotiations: reluctance to making Integrative Gambit Offers

In the present study we address a multi‐issue negotiation agenda, where several issues are under consideration and parties have different priorities among these issues. We suggest that in such agendas loss aversion and within issue anchoring may constrain the configuration of offers that parties propose to each other during the course of negotiation. We specifically focus on offers in which negotiators self‐propose to give the other party more than was demanded on one of the issues, while still maintaining or improving their overall value. We term such offers Integrative Gambit Offers (“IGO”s) and show that although making such offers improves integrative negotiation outcome, the frequency of making them is relatively low, and does not increase as negotiators gain experience with the task. Copyright © 2006 John Wiley & Sons, Ltd.     

Effects of scenery, lighting, glideslope, and experience on timing the landing flare

This study examined three visual strategies for timing the initiation of the landing flare based on perceptions of either: (a) a critical height above ground level; (b) a critical runway width angle (Psi); or (c) a critical time-to-contact (TTC) with the runway. Visual displays simulated landing approaches with trial-to-trial variations in glideslope, lighting, and scene detail. Twenty-four participants (8 private pilots, 8 student pilots, and 8 nonpilots) were instructed to initiate the flare when they perceived that their TTC with the runway (30 m wide by 840 m long) had reached a critical value of 2 seconds. Our results demonstrated a significant effect of flight experience on flare timing accuracy and dominance of the height-based strategy over the runway-width-angle and TTC-based strategies. (PsycINFO Database Record (c) 2008 APA, all rights reserved).