The Mental Representation of Human Action

Various theories of moral cognition posit that moral intuitions can be understood as the output of a computational process performed over structured mental representations of human action. We propose that action plan diagrams—“act trees”—can be a useful tool for theorists to succinctly and clearly present their hypotheses about the information contained in these representations. We then develop a methodology for using a series of linguistic probes to test the theories embodied in the act trees. In Study 1, we validate the method by testing a specific hypothesis (diagrammed by act trees) about how subjects are representing two classic moral dilemmas and finding that the data support the hypothesis. In Studies 2–4, we explore possible explanations for discrete and surprising findings that our hypothesis did not predict. In Study 5, we apply the method to a less well‐studied case and show how new experiments generated by our method can be used to settle debates about how actions are mentally represented. In Study 6, we argue that our method captures the mental representation of human action better than an alternative approach. A brief conclusion suggests that act trees can be profitably used in various fields interested in complex representations of human action, including law, philosophy, psychology, linguistics, neuroscience, computer science, robotics, and artificial intelligence.     

Credible suggestions affect false autobiographical beliefs

False memory implantation studies are characterised by suggestions indicating that specific unremembered events occurred, attributing suggested events to a knowledgeable source (e.g., parents), and including true events that provide evidence that this source was consulted. These characteristics create a particular retrieval context that influences how individuals come to believe that false events occurred. Two studies used a variant of implantation methods to vary the proportion of events attributed to parents and the presence of true events within the suggestion. In Study 1 participants received six false events, and were told that all or some events came from parents. Participants told that all of the events came from parents formed more and stronger false beliefs. In Study 2 participants also received two true events, and a third group was told that half of the events came from their parents. Participants given the specific ratio ("half") endorsed more false beliefs, and beliefs between the other groups no longer differed. Across both studies participants told that some events came from parents reported stronger memory phenomenology. The effect of suggestions on false beliefs in implantation studies depends partly on the credibility of suggestions derived from providing information about the source of suggested events.     

Reverse causation in activity-cognitive ability associations: the Lothian Birth Cohort 1936

Active lifestyles might protect cognitive abilities; however, studies rarely consider the reverse causal direction. Activity-cognition associations might reflect stable intelligence differences rather than a protective effect of activity. The Lothian Birth Cohort 1936 (n = 1091) completed cognitive tests aged 70, having taken an intelligence test aged 11. Activity (assessed by participation in 15 activities that produced a socio-intellectual activity factor, and by physical activity) was positively associated with cognition (r = .08 to .32, p ≤ .05). When age-11 IQ and adult social class were controlled, only physical activity remained significantly associated with general cognitive ability and processing speed.     

A Randomized, Double-Blind, Crossover Comparison of MK-0929 and Placebo in the Treatment of Adults With ADHD

Objective: Preclinical models, receptor localization, and genetic linkage data support the role of D4 receptors in the etiology of ADHD. This proof-of-concept study was designed to evaluate MK-0929, a selective D4 receptor antagonist as treatment for adult ADHD. Method: A randomized, double-blind, placebo-controlled, crossover study was conducted in adults with primary ADHD. The primary end point was changed from baseline in total score on the Adult ADHD Investigator Symptom Rating Scale following a 4-week treatment regimen. Additional measures included Clinical Global Impression-Severity Scale, Hospital Anxiety and Depression Scale, and Brown Attention Deficit Disorder Scale and D4 genotype analysis. Results: No statistically significant treatment differences were found between MK-0929 and placebo in any of the primary or secondary assessments. Conclusion: Results from this study suggest that blockade of the D4 receptor alone is not efficacious in the treatment of adult ADHD.     

An empirical examination of distributional assumptions underlying the relationship between personality disorder symptoms and personality traits

This article examines the relationship between personality disorder (PD) symptoms and personality traits using a variety of distributional assumptions. Prior work in this area relies almost exclusively on linear models that treat PD symptoms as normally distributed and continuous. However, these assumptions rarely hold, and thus the results of prior studies are potentially biased. Here we explore the effect of varying the distributions underlying regression models relating PD symptomatology to personality traits using the initial wave of the Longitudinal Study of Personality Disorders (N = 250; Lenzenweger, 1999), a university-based sample selected to include PD rates resembling epidemiological samples. PD symptoms were regressed on personality traits. The distributions underlying the dependent variable (i.e., PD symptoms) were variously modeled as normally distributed, as counts (Poisson, Negative-Binomial), and with two-part mixture distributions (zero-inflated, hurdle). We found that treating symptoms as normally distributed resulted in violations of model assumptions, that the negative-binomial and hurdle models were empirically equivalent, but that the coefficients achieving significance often differ depending on which part of the mixture distributions are being predicted (i.e., presence vs. severity of PD). Results have implications for how the relationship between normal and abnormal personality is understood. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

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.     

Student ethics in an era of personal entitlement

397 students arriving to take an exam in a junior level Principles of Management course were clearly warned on several occasions to keep cell phones outside the testing area or receive a failing test grade if the policy was violated. Just before the examination was administered, with all students sitting in their assigned seats, the professor made a final announcement that anyone still in possession of a cell phone would have one last opportunity to come forward and place it in a box at the front of the testing room. After eight students accepted this final "opportunity," the professor produced a hand-held metal detector, demonstrated how it could detect cell phones placed inside clothing, and informed the class that random screening of students would be conducted as they handed in their examinations. He then added that, as a special favor, he would allow a two-minute amnesty period during which any student could bring a cell phone to the front of the room for storage during the test. 38 students responded by turning in cell phones they had retained in direct violation of course policy. Implications of this cell phone dishonesty for creating viable business ethics and the role of perceived entitlement in shaping the behavior of these future business leaders were discussed.     

Scepticism, perceptual knowledge, and doxastic responsibility

Arguments for scepticism about perceptual knowledge are often said to have intuitively plausible premises. In this discussion I question this view in relation to an argument from ignorance and argue that the supposed persuasiveness of the argument depends on debatable background assumptions about knowledge or justification. A reasonable response to scepticism has to show there is a plausible epistemological perspective that can make sense of our having perceptual knowledge. I present such a perspective. In order give a more satisfying response to scepticism, we need also to consider the standing of background beliefs. This is required since the recognitional abilities that enable us to have perceptual knowledge are informed by, or presuppose, a picture or conception of the world the correctness of which we have not ascertained. The question is how, in the face of this, to make sense of responsible belief-formation. In addressing this problem I make a suggestion about the standing of certain crucial beliefs linking appearances with membership of kinds.     

Rationality and indeterminate probabilities

We argue that indeterminate probabilities are not only rationally permissible for a Bayesian agent, but they may even be rationally required. Our first argument begins by assuming a version of interpretivism: your mental state is the set of probability and utility functions that rationalize your behavioral dispositions as well as possible. This set may consist of multiple probability functions. Then according to interpretivism, this makes it the case that your credal state is indeterminate. Our second argument begins with our describing a world that plausibly has indeterminate chances. Rationality requires a certain alignment of your credences with corresponding hypotheses about the chances. Thus, if you hypothesize the chances to be indeterminate, your will inherit their indeterminacy in your corresponding credences. Our third argument is motivated by a dilemma. Epistemic rationality requires you to stay open-minded about contingent matters about which your evidence has not definitively legislated. Practical rationality requires you to be able to act decisively at least sometimes. These requirements can conflict with each other-for thanks to your open-mindedness, some of your options may have undefined expected utility, and if you are choosing among them, decision theory has no advice to give you. Such an option is playing Nover and Hájek??s Pasadena Game, and indeed any option for which there is a positive probability of playing the Pasadena Game. You can serve both masters, epistemic rationality and practical rationality, with an indeterminate credence to the prospect of playing the Pasadena game. You serve epistemic rationality by making your upper probability positive-it ensures that you are open-minded. You serve practical rationality by making your lower probability 0-it provides guidance to your decision-making. No sharp credence could do both.     

Distinguishing different strategies of across-dimension attentional selection

Selective attention in multidimensional displays has usually been examined using search tasks requiring the detection of a single target. We examined the ability to perceive a spatial structure in multi-item subsets of a display that were defined either conjunctively or disjunctively. Observers saw two adjacent displays and indicated whether the to-be-selected items within the two displays matched in terms of their spatial structure (the identity of the corresponding items within these subsets was not relevant to the task). The observers in our study could readily perceive conjunctively defined subsets, but had great difficulty with disjunctively defined subsets. The results pose a challenge to the popular idea that attention is guided by a "priority map" that sums bottom-up and top-down factors, whereas they are directly predicted by Boolean map theory of visual attention.