Putting the elephant back in the herd: elephant relative quantity judgments match those of other species

The ability to discriminate between quantities has been observed in many species. Typically, when an animal is given a choice between two sets of food, accurate performance (i.e., choosing the larger amount) decreases as the ratio between two quantities increases. A recent study reported that elephants did not exhibit ratio effects, suggesting that elephants may process quantitative information in a qualitatively different way from all other nonhuman species that have been tested (Irie-Sugimoto et al. in Anim Cogn 12:193-199, 2009). However, the results of this study were confounded by several methodological issues. We tested two African elephants (Loxodonta africana) to more thoroughly investigate relative quantity judgment in this species. In contrast to the previous study, we found evidence of ratio effects for visible and nonvisible sequentially presented sets of food. Thus, elephants appear to represent and compare quantities in much the same way as other species, including humans when they are prevented from counting. Performance supports an accumulator model in which quantities are represented as analog magnitudes. Furthermore, we found no effect of absolute magnitude on performance, providing support against an object-file model explanation of quantity judgment.     

Bridging a yawning chasm: EEG investigations into the debate concerning the role of the human mirror neuron system in contagious yawning

Ongoing debate in the literature concerns whether there is a link between contagious yawning and the human mirror neuron system (hMNS). One way of examining this issue is with the use of the electroencephalogram (EEG) to measure changes in mu activation during the observation of yawns. Mu oscillations are seen in the alpha bandwidth of the EEG (8–12 Hz) over sensorimotor areas. Previous work has shown that mu suppression is a useful index of hMNS activation and is sensitive to individual differences in empathy. In two experiments, we presented participants with videos of either people yawning or control stimuli. We found greater mu suppression for yawns than for controls over right motor and premotor areas, particularly for those scoring higher on traits of empathy. In a third experiment, auditory recordings of yawns were compared against electronically scrambled versions of the same yawns. We observed greater mu suppression for yawns than for the controls over right lateral premotor areas. Again, these findings were driven by those scoring highly on empathy. The results from these experiments support the notion that the hMNS is involved in contagious yawning, emphasise the link between contagious yawning and empathy, and stress the importance of good control stimuli.     

The destructive nature of power without status

The current research explores how roles that possess power but lack status influence behavior toward others. Past research has primarily examined the isolated effects of having either power or status, but we propose that power and status interact to affect interpersonal behavior. Based on the notions that a) low-status is threatening and aversive and b) power frees people to act on their internal states and feelings, we hypothesized that power without status fosters demeaning behaviors toward others. To test this idea, we orthogonally manipulated both power and status and gave participants the chance to select activities for their partners to perform. As predicted, individuals in high-power/low-status roles chose more demeaning activities for their partners (e.g., bark like a dog, say “I am filthy”) than did those in any other combination of power and status roles. We discuss how these results clarify, challenge, and advance the existing power and status literatures.     

Social connection enables dehumanization

Being socially connected has considerable benefits for oneself, but may have negative consequences for evaluations of others. In particular, being socially connected to close others satisfies the need for social connection, and creates disconnection from more distant others. We therefore predicted that feeling socially connected would increase the tendency to dehumanize more socially distant others. Four experiments support this prediction. Those led to feel socially connected were less likely to attribute humanlike mental states to members of various social groups (Experiments 1 and 2), particularly distant others compared to close others (Experiment 3), and were also more likely to recommend harsh treatment for dehumanized others (i.e., terrorist detainees, Experiment 4). Discussion addresses the mechanisms by which social connection enables dehumanization, and the varied behavioral implications that result.     

The reciprocal link between multiculturalism and perspective-taking: How ideological and self-regulatory approaches to managing diversity reinforce each other

Five experiments tested the hypothesis that there is a bi-directional link between ideological (multiculturalism and color-blindness) and self-regulatory (perspective-taking and stereotype-suppression) approaches to managing diversity. A first set of experiments found that exposure to multiculturalism facilitated perceptual and conceptual forms of perspective-taking. Specifically, a multicultural ideology prime strengthened motivations to engage in perspective-taking (Experiment 1) and led participants to adopt spontaneously an outgroup target's visual perspective (Experiment 2) and to recognize that an outgroup target did not possess their privileged knowledge (Experiment 3), as compared with a color-blind ideology prime or baseline condition. A second set of experiments documented the reciprocal relationship: Actively considering an outgroup member's perspective strengthened both deliberate (Experiment 4) and automatic (Experiment 5) positivity toward multiculturalism relative to color-blindness. These findings suggest that ideological and self-regulatory approaches to diversity management are intimately connected and can reinforce each other.     

The name-pronunciation effect: Why people like Mr. Smith more than Mr. Colquhoun

Names are rich sources of information. They can signal gender, ethnicity, or class; they may connote personality characteristics ranging from warmth and cheerfulness to morality. But names also differ in a much more fundamental way: some are simply easier to pronounce than others. Five studies provide evidence for the name-pronunciation effect: easy-to-pronounce names (and their bearers) are judged more positively than difficult-to-pronounce names. Studies 1–3 demonstrate that people form more positive impressions of easy-to-pronounce names than of difficult-to-pronounce names. Study 4 finds this effect generalizable to ingroup targets. Study 5 highlights an important real-world implication of the name-pronunciation effect: people with easier-to-pronounce surnames occupy higher status positions in law firms. These effects obtain independent of name length, unusualness, typicality, foreignness, and orthographic regularity. This work demonstrates the potency of processing fluency in the information rich context of impression formation.     

Sexy red: Perceived sexual receptivity mediates the red-attraction relation in men viewing woman

In many non-human primate species, female red displays are a signal of sexual receptivity and this signal attracts male conspecifics. In the present research, we proposed and tested a human analog whereby perceived sexual receptivity mediates the relation between red and sexual attraction in men viewing women. Two experiments were conducted, each of which provided support for the hypothesized mediational model. Experiment 1 documented the mediational role of perceived sexual receptivity using the experimental–causal-chain approach, and Experiment 2 did so using the measurement-of-mediation approach. Alternative mediator variable candidates were ruled out, and participants showed no evidence of awareness of the red effect. These findings document red as a subtle, but surprisingly powerful environmental stimulus that can serve parallel functions in the mating game for human and non-human primates.     

A facial expression for anxiety

Anxiety and fear are often confounded in discussions of human emotions. However, studies of rodent defensive reactions under naturalistic conditions suggest anxiety is functionally distinct from fear. Unambiguous threats, such as predators, elicit flight from rodents (if an escape-route is available), whereas ambiguous threats (e.g., the odor of a predator) elicit risk assessment behavior, which is associated with anxiety as it is preferentially modulated by anti-anxiety drugs. However, without human evidence, it would be premature to assume that rodent-based psychological models are valid for humans. We tested the human validity of the risk assessment explanation for anxiety by presenting 8 volunteers with emotive scenarios and asking them to pose facial expressions. Photographs and videos of these expressions were shown to 40 participants who matched them to the scenarios and labeled each expression. Scenarios describing ambiguous threats were preferentially matched to the facial expression posed in response to the same scenario type. This expression consisted of two plausible environmental-scanning behaviors (eye darts and head swivels) and was labeled as anxiety, not fear. The facial expression elicited by unambiguous threat scenarios was labeled as fear. The emotion labels generated were then presented to another 18 participants who matched them back to photographs of the facial expressions. This back-matching of labels to faces also linked anxiety to the environmental-scanning face rather than fear face. Results therefore suggest that anxiety produces a distinct facial expression and that it has adaptive value in situations that are ambiguously threatening, supporting a functional, risk-assessing explanation for human anxiety.