Hippocampal sequences link past, present, and future

Disrupting the reactivation of hippocampal neurons during sleep impairs memory consolidation in rats. However, the functional importance of reactivation during awake states is unknown. An experiment in which awake reactivation was disrupted suggests that this phenomenon could adaptively guide behavior by linking previous learning with the current state of the world.     

Automated assembly of optimally spaced and balanced paired comparisons: Controlling order effects

To control order effects in questionnaires containing paired comparisons, Ross (1934) described an optimal ordering of the pairings. The pairs can also be balanced so that every stimulus appears equal numbers of times as the first and the second member of a pair. First, we describe and illustrate the optimally spaced, balanced ordering of pairings. Then we show how the optimally spaced, balanced order can be used to implement a matrix-sampling design or a fully incomplete design when the number of stimuli n is so large that respondents cannot reasonably be expected to judge all n(n - 1)/2 pairs. The algorithm for balancing and optimally spacing the list of pairs is described.     

Moving through virtual reality without moving?

Virtual reality (VR) technology is increasingly used in spatial cognition research, as it offers high experimental control and interactivity in naturalistic multi-modal environments, something that is difficult to achieve in real-world settings. Even in the most sophisticated and costly VR systems, people do not necessarily perceive and behave as they would in the real world. This might be related to our inability to use embodied (and thus often highly automated and effective) spatial orientation processes in VR. While real-world locomotion affords automatic and obligatory spatial updating of our self-to-surrounding relationships, such that we easily remain oriented during simple perspective changes, the same is not necessarily true in VR. This can lead to striking systematic and qualitative errors such as failures to update rotations ("Nonturner" behavior). Here, we investigated whether rich naturalistic visual stimuli in immersive VR might be sufficient to compensate for the lack of physical motion. To this end, 24 participants performed point-to-origin tasks after visually simulated excursions along streets of varying curvature in a naturalistic virtual city. Most (21/24) participants properly updated simulated self-motions and showed only moderate regression toward mean pointing responses. 3/24 participants, however, exhibited striking "Nonturner" behavior in that they pointed as if they did not update the visually simulated turns and their heading had not changed. This suggests that our immersive naturalistic VR stimuli were an improvement over prior optic flow stimuli, but still insufficient in eliciting obligatory spatial updating that supported correct point-to-origin responses in all participants.     

Secularity and biblical literalism: confronting the case for epistemological diversity

Stephen Carter argues that biblical literalism is predicated on an epistemological position drastically different than that maintained by mainstream scientists inasmuch as it operates on the basis of a “hermeneutic of inerrancy” with respect to the ideas laid out in the Bible. By relying on considerations offered by Charles Taylor and recent sociological studies, I contend that Carter’s thesis is incorrect. The divide between proponents and opponents of biblical literalism is ethical rather than epistemological. Beyond the philosophical implications of my contention, this displays that deliberative engagement between these parties—which depends on shared epistemological norms—is possible in principle.     

An invariant dimensional liability model of gender differences in mental disorder prevalence: evidence from a national sample

Epidemiological studies of categorical mental disorders consistently report that gender differences exist in many disorder prevalence rates and that disorders are often comorbid. Can a dimensional multivariate liability model be developed to clarify how gender impacts diverse, comorbid mental disorders? We pursued this possibility in the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC; N = 43,093). Gender differences in prevalence were systematic such that women showed higher rates of mood and anxiety disorders, and men showed higher rates of antisocial personality and substance use disorders. We next investigated patterns of disorder comorbidity and found that a dimensional internalizing-externalizing liability model fit the data well, where internalizing is characterized by mood and anxiety disorders, and externalizing is characterized by antisocial personality and substance use disorders. This model was gender invariant, indicating that observed gender differences in prevalence rates originate from women and men's different average standings on latent internalizing and externalizing liability dimensions. As hypothesized, women showed a higher mean level of internalizing, while men showed a higher mean level of externalizing. We discuss implications of these findings for understanding gender differences in psychopathology and for classification and intervention.     

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.     

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.