Quantifying variability in phase portraits: application to gait ontogeny

We describe new Fourier- and shape-based methods for quantifying variation in phase-portraits, and re-analyze previously-published ontogenetic and adult data [Clark, J. E., & Phillips, S. J. (1993). A longitudinal study of intralimb coordination in the first year of independent walking: A dynamical systems approach. Child Development, 64, 1143–1157]. Results show considerable variation between individuals and through development, but after 6 months of walking some gait patterns stabilize.     

Attractor dynamics and semantic neighborhood density: processing is slowed by near neighbors and speeded by distant neighbors

The authors investigated semantic neighborhood density effects on visual word processing to examine the dynamics of activation and competition among semantic representations. Experiment 1 validated feature-based semantic representations as a basis for computing semantic neighborhood density and suggested that near and distant neighbors have opposite effects on word processing. Experiment 2 confirmed these results: Word processing was slower for dense near neighborhoods and faster for dense distant neighborhoods. Analysis of a computational model showed that attractor dynamics can produce this pattern of neighborhood effects. The authors argue for reconsideration of traditional models of neighborhood effects in terms of attractor dynamics, which allow both inhibitory and facilitative effects to emerge.     

Learning correct responses and errors in the Hebb repetition effect: two faces of the same coin

In a serial recall task, the Hebb repetition effect occurs when recall performance improves for a sequence repeated throughout the experimental session. This phenomenon has been replicated many times. Nevertheless, such cumulative learning seldom leads to perfect recall of the whole sequence, and errors persist. Here the authors report evidence that there is another side to the Hebb repetition effect that involves learning errors produced in a repeated sequence. A learning measure based on past recalls (correct or incorrect) shows that the probability of a given response increases with the number of prior occurrences of that response. The pattern of results reveals another manifestation of the Hebb repetition effect and speaks to the nature of implicit learning.     

The human Müller-Lyer illusion in goalkeeping

We examined whether a goalkeeper can influence a penalty-taker's actions by assuming postures that mimic Müller-Lyer configurations. The results of two studies indicate that (i) goalkeeper posture affects the perception of the goalkeeper's height in a manner consistent with the Müller-Lyer illusion; (ii) this influences penalty-taking accuracy; and (iii) a posture which resembles a wing-out Müller-Lyer configuration results in wider and lower throws.     

That “Ought” Does Not Imply “Right”: Why It Matters for Virtue Ethics

Virtue ethicists sometimes say that a right action is what a virtuous person would do, characteristically, in the circumstances. But some have objected recently that right action cannot be defined as what a virtuous person would do in the circumstances because there are circumstances in which a right action is possible but in which no virtuous person would be found. This objection moves from the premise that a given person ought to do an action that no virtuous person would do, to the conclusion that the action is a right action. I demon‐strate that virtue ethicists distinguish “ought” from “right” and reject the assumption that “ought” implies “right.” I then show how their rejection of that assumption blocks this “right but not virtuous” objection. I conclude by showing how the thesis that “ought” does not imply “right” can clarify a further dispute in virtue ethics regarding whether “ought” implies “can.”     

Conservatives and Racists: Inferential Role Semantics and Pejoratives

According to inferential role semantics (IRS), for any given expression to possess a particular meaning one must be disposed to make or, alternatively, acknowledge as correct certain inferential transitions involving it. As Williamson points out, pejoratives such as ‘Boche’ seem to provide a counter-example to IRS. Many speakers are neither disposed to use such expressions nor consider it proper to do so. But it does not follow, as IRS appears to entail, that such speakers do not understand pejoratives or that they lack meaning. In this paper, I examine recent responses to this problem by Boghossian and Brandom and argue that their proposed construal of the kind of inferential rules governing a pejorative such as ‘Boche’ is to be ruled out on the grounds that it is non-conservative. I defend the appeal to conservatism in this instance against criticism and, in doing so, propose an alternative approach to pejoratives on behalf of IRS that resolves the problem Williamson poses.

Cue-framing effects in source remembering: A memory misattribution model

During source remembering, selectively emphasizing one source in the retrieval query “Is this item from Source A?” can yield different accuracy than emphasizing the alternate source in “Is this item from Source B?” even if those are the only two possible origins. One account of this cue-framing effect holds that it reflects different active monitoring strategies encouraged by the two cue frames. An item memory misattribution (IMM) model instead assumes that this effect reflects the uncontrolled use of item recognition during confirmatory source judgments, and an IMM model simulation predicted a quantitative relationship between recognition levels and the cue-framing effect. Experiments 1 and 3 confirmed these predictions by using study repetitions to manipulate recognition levels, and Experiments 2 and 3 also demonstrated the effect with new source tasks not previously considered. The data suggest that, in addition to qualitative monitoring strategies, subjects also use the availability of item memory in a heuristic fashion during confirmatory source attributions.     

Family Intervention Effects on Co-occurring Early Childhood Behavioral and Emotional Problems: A Latent Transition Analysis Approach

This study used latent transition analysis (LTA) to examine changes in early emotional and behavioral problems in children age 2 to 4 years resulting from participation in a family-centered intervention. A sample of 731 economically disadvantaged families was recruited from among participants in a national food supplement and nutrition program. Families with toddlers between age 2 and 3 were randomized either to the Family Check-Up (FCU) or to a nonintervention control group. The FCU’s linked interventions were tailored to each family’s needs. Assessments occurred at age 2, 3, and 4. The FCU followed age 2 and age 3 assessments. Latent class analyses were conducted on mother reports of behavior and emotional problems from age 2 to 4 to study transitions among the following four groups: (a) externalizing only, (b) internalizing only, (c) comorbid internalizing and externalizing, and (d) normative. LTA results revealed that participation in the FCU increased the likelihood of transitioning from either the comorbid or the internalizing class into the normative class by age 4. These results suggest family interventions in early childhood can potentially disrupt the early emergence of both emotional and behavioral problems.     

The Effects of Incentives on Visual–Spatial Working Memory in Children with Attention-deficit/Hyperactivity Disorder

Working memory is one of several putative core neurocognitive processes in attention-deficit/hyperactivity disorder (ADHD). The present work seeks to determine whether visual–spatial working memory is sensitive to motivational incentives, a laboratory analogue of behavioral treatment. Participants were 21 children (ages 7–10) with a diagnosis of ADHD-combined type. Participants completed a computerized spatial span task designed to assess storage of visual–spatial information (forward span) and manipulation of the stored information (backward span). The spatial span task was completed twice on the same day, once with a performance-based incentive (trial-wise feedback and points redeemable for prizes) and once without incentives. Participants performed significantly better on the backward span when rewarded for correct responses, compared to the no incentive condition. However, incentives had no effect on performance during the forward span. These findings may suggest the use of motivational incentives improved manipulation, but not storage, of visual–spatial information among children with ADHD. Possible explanations for the differential incentive effects are discussed, including the possibility that incentives prevented a vigilance decrement as task difficulty and time on task increased.     

Maternal Predictors of Rejecting Parenting and Early Adolescent Antisocial Behavior

The present study examined relations among maternal psychological resources, rejecting parenting, and early adolescent antisocial behavior in a sample of 231 low-income mothers and their sons with longitudinal assessments from age 18 months to 12 years. The maternal resources examined were age at first birth, aggressive personality, and empathy. Each of the maternal resources predicted rejecting parenting during early childhood in structural equation models that controlled for toddler difficult temperament, and rejecting parenting in early childhood predicted antisocial behavior in early adolescence. Rejecting parenting accounted for the indirect effect of each of the maternal resources on antisocial behavior, but a direct effect was also supported between maternal aggressive personality and youth antisocial behavior. Results highlight the importance of these relatively understudied maternal resources and have implications for prevention and intervention programs that focus on parenting during early childhood.