Differential effects of scopolamine and lorazepam on working memory maintenance versus manipulation processes

Between-study comparisons of benzodiazepine and anticholinergic drugs on working memory suggest that anticholinergics may produce greater impairment in maintenance processes, whereas benzodiazepines may produce greater impairment in manipulation processes. This study directly compared acute effects of the benzodiazepine lorazepam (1.0 and 2.0 mg/70 kg, orally administered) and the anticholinergic scopolamine (0.25 and 0.50 mg/ 70 kg, subcutaneously administered) on working memory maintenance (storage and rehearsal) and manipulation processes in a placebo-controlled, double-dummy, double-blind, crossover design in 20 healthy volunteers. Using a modified Sternberg paradigm, storage, rehearsal, and manipulation processes were parametrically manipulated by varying memory load, delay between stimulus presentation and test, and number of operations performed on the letter strings, respectively, while controlling for drug effects on nonmemory processes. As predicted, the results suggested greater impairment in maintenance processes (rehearsal) with scopolamine than with lorazepam and greater impairment in manipulation processes with lorazepam than with scopolamine. In addition, the results suggested greater overall slowing of working memory processes with lorazepam.     

Group membership,group norms,empathy, and young children's intentions to aggress

This study assessed the effect of ingroup norms and empathy on 6 and 9‐year‐old children's (N=161) attitudes and aggressive intentions toward outgroup members. Prior to an intergroup drawing competition against an outgroup, participants' empathy was measured, and they were randomly assigned to a simulated group with a norm of direct or indirect aggression, or no aggression norm. Results indicated participants' attitudes were less positive toward the outgroup vs. the ingroup, and that both direct and indirect aggressive intentions were displayed toward the outgroup. Most importantly, the ingroup was liked less when it had an aggression norm, and the participants' aggressive intentions were not enhanced by the group aggression norm. Empathy was a significant negative predictor of direct but not indirect aggression intentions. Implications for understanding the instigation and inhibition of children's aggression intentions are discussed. Aggr. Behav. 35:244–258, 2009. © 2009 Wiley‐Liss, Inc.     

How to Be Helpful to Multiple People at Once

When someone hosts a party, when governments choose an aid program, or when assistive robots decide what meal to serve to a family, decision-makers must determine how to help even when their recipients have very different preferences. Which combination of people’s desires should a decision-maker serve? To provide a potential answer, we turned to psychology: What do people think is best when multiple people have different utilities over options? We developed a quantitative model of what people consider desirable behavior, characterizing participants’ preferences by inferring which combination of “metrics” (maximax, maxsum, maximin, or inequality aversion [IA]) best explained participants’ decisions in a drink-choosing task. We found that participants’ behavior was best described by the maximin metric, describing the desire to maximize the happiness of the worst-off person, though participant behavior was also consistent with maximizing group utility (the maxsum metric) and the IA metric to a lesser extent. Participant behavior was consistent across variation in the agents involved and  tended to become more maxsum-oriented when participants were told they were players in the task (Experiment 1). In later experiments, participants maintained maximin behavior across multi-step tasks rather than shortsightedly focusing on the individual steps therein (Experiment 2, Experiment 3). By repeatedly asking participants what choices they would hope for in an optimal, just decision-maker, and carefully disambiguating which quantitative metrics describe these nuanced choices, we help constrain the space of what behavior we desire in leaders, artificial intelligence systems helping decision-makers, and the assistive robots and decision-makers of the future.     

Episodic memory: what can animals remember about their past?

The question of whether episodic memory, the ability to recall unique, personal experiences, is restricted to humans is a matter of current controversy. Recent work on food-storing jays suggests that several features of episodic memory may not be as exclusive to humans as previously thought. In this review we outline the critical features of episodic memory in humans, its relationship to declarative memory, and recent results revealing that jays can learn to perform a task that depends on certain features of episodic memory and can thus be considered 'episodic-like'. Finally, we compare this avian performance with a contemporary definition of human episodic memory and consider the implications for studies of hippocampal function and animal cognition.     

Facebook addiction: concerns, criticism, and recommendations--a response to Andreassen and colleagues

This paper provides a brief critique of the Facebook addiction research field in relation to the Bergen Facebook Addiction Scale developed by Andreaessen and colleagues (2012). Just like the term "Internet addiction," the term "Facebook addiction" may already be obsolete because there are many activities that a person can engage in on the Facebook website (e.g., messaging friends, playing games like Farmville, and gambling). What is needed is a new psychometric scale examining potential addiction to a particular online application (i.e., social networking) rather than activity on a particular website (i.e., Facebook).     

Measuring rail passenger crowding: Scale development and psychometric properties

Research on rail passenger crowding often tacitly subscribes to a measurement of crowding based on density (i.e. physical conditions involving space limitations) and rarely considers the possible role psychological factors may play in measuring this construct. This paper describes the development of an instrument that captures the dimensionality of rail passenger crowding and its relationship to the experience of stress and feelings of exhaustion. The proposed instrument is a 20-item self-rating questionnaire consisting of three sub-scales designed to assess subjective crowding experiences among rail users (n = 525). Findings from the factor analyses generally support the hypothesised three-factor structure of the measurement model (evaluation of the psychosocial aspects of the crowded situation, evaluation of the ambient environment of the crowded situation, and affective reactions to the crowded situation). All sub-scales demonstrate excellent internal consistency and construct validity as well as good convergent and discriminant validity values. The instrument was further tested using structural equation modelling to examine the impact of crowding on commuters’ stress and feelings of exhaustion. With the addition of the “passenger density” variable as an indicator of objective measurement of crowding operating in tandem with the crowding sub-scales, the results reveal that: (1) commuters’ evaluations of the psychosocial aspects of the crowded situation and of its ambient environment, alongside their rating of passenger density, significantly predict affective reactions to the crowded situation; (2) these affective reactions, in turn, significantly predict stress and feelings of exhaustion; and (3) evaluations of the psychosocial aspects of the crowded situation and of its ambient environment as well as passenger density do not directly predict stress and feelings of exhaustion. The link between rail passenger crowding and the negative outcomes therefore does not appear as a simple, direct relationship, but is mediated by affective feelings of crowdedness. Overall, these results provide satisfactory psychometric properties for the proposed instrument and support its use as an assessment tool for measuring crowding experience in the rail setting.     

Predictive gaze cues affect face evaluations: The effect of facial emotion

When we see someone change their direction of gaze, we spontaneously follow their eyes because we expect people to look at interesting objects. Bayliss and Tipper (2006) examined the consequences of observing this expectancy being either confirmed or violated by faces producing reliable or unreliable gaze cues. Participants viewed different faces that would consistently look at the target, or consistently look away from the target: The faces that consistently looked towards targets were subsequently chosen as being more trustworthy than the faces that consistently looked away from targets. The current work demonstrates that these gaze contingency effects are only detected when faces create a positive social context by smiling, but not in the negative context when all the faces held angry or neutral expressions. These data suggest that implicit processing of the reward contingencies associated with gaze cues relies on a positive emotional expression to maintain expectations of a favourable outcome of joint attention episodes.     

Active versus passive maintenance of visual nonverbal memory

Forgetting over the short term has challenged researchers for more than a century, largely because of the difficulty of controlling what goes on within the memory retention interval. But the “recent-negative-probe” procedure offers a valuable paradigm, by examining the influences of (presumably) unattended memoranda from prior trials. Here we used a recent-probe task to investigate forgetting for visual nonverbal short-term memory. The target stimuli (two visually presented abstract shapes) on a trial were followed after a retention interval by a probe, and participants indicated whether the probe matched one of the target items. Proactive interference, and hence memory for old trial probes, was observed, whereby participants were slowed in rejecting a nonmatching probe on the current trial that nevertheless matched a target item on the previous trial (a recent-negative probe). The attraction of the paradigm is that, by uncovering proactive influences of past-trial probe stimuli, it can be argued that active maintenance in memory of those probes is unlikely. In two experiments, we recorded such proactive interference of prior-trial items over a range of interstimulus (ISI) and intertrial (ITI) intervals (between 1 and 6 s, respectively). Consistent with a proposed two-process memory conception (the active–passive memory model, or APM), actively maintained memories on current trials decayed, but passively “maintained,” or unattended, visual memories of stimuli on past trials did not.     

Reinflating Logical Consequence

Shapiro (Philos Q 61:320–342, 2011) argues that, if we are deflationists about truth, we should be deflationists about logical consequence. Like the truth predicate, he claims, the logical consequence predicate is merely a device of generalisation and more substantial characterisation, e.g. proof- or model-theoretic, is mistaken. I reject his analogy between truth and logical consequence and argue that, by appreciating how the logical consequence predicate is used as well as the goals of proof theory and model theory, we can be deflationists about truth but not logical consequence.     

Meditation Awareness Training (MAT) for Improved Psychological Well-being: A Qualitative Examination of Participant Experiences

Mindfulness-based interventions are reported as being efficacious treatments for a variety of psychological and somatic conditions. However, concerns have arisen relating to how mindfulness is operationalized in mindfulness-based interventions and whether its ‘spiritual essence’ and full potential treatment efficacy have remained intact. This qualitative study used interpretative phenomenological analysis to examine participant experiences regarding the acceptability and effectiveness of a newly designed secularized intervention called meditation awareness training (MAT) that follows a more traditional Buddhist approach to meditation. Participants (with issues of stress and low mood) reported experiencing improvements in psychological well-being due to receiving MAT. The wider implications are discussed.