A laboratory school comparison of mixed amphetamine salts extended release (Adderall XR) and atomoxetine (Strattera) in school-aged children with attention deficit/hyperactivity disorder

Mixed amphetamine salts extended release (MAS XR; Adderall XR) and atomoxetine (Strattera) were compared in children 6 to 12 years old with attention deficit/hyperactivity disorder (ADHD) combined or hyperactive/impulsive type in a randomized, double-blind, multicenter, parallel-group, forced-dose-escalation laboratory school study. Primary efficacy measure was the SKAMP (Swanson, Kotkin, Agler, M-Flynn, and Pelham) behavioral rating scale. Changes in mean SKAMP deportment scores from baseline were significantly greater for MAS XR (n = 102) than for atomoxetine (n = 101) overall (-0.56 and -0.13, respectively; p < .0001) and at each week (p < .001). Adverse events were similar for both treatment groups. The extended time course of action and greater therapeutic efficacy of MAS XR suggests that it is more effective than atomoxetine in children with ADHD.     

Maladaptive conflict monitoring as evidence for executive dysfunction in children with chromosome 22q11.2 deletion syndrome

Using an adaptation of the Attentional Networks Test, we investigated aspects of executive control in children with chromosome 22q11.2 deletion syndrome (DS22q11.2), a common but not well understood disorder that produces non-verbal cognitive deficits and a marked incidence of psychopathology. The data revealed that children with DS22q11.2 demonstrated greater difficulty than controls in locating and processing target items in the presence of distracters. Importantly, children with DS22q11.2 showed a deficit in the ability to monitor and adapt to stimulus conflict. These data provide evidence of inadequate conflict adaptation in children with DS22q11.2, a problem that is also present in schizophrenia. The findings of specific executive dysfunction in this group may provide a linkage between particular genetic abnormalities and the development of psychopathology.     

Information processing limitations as revealed by temporal discrimination

Information processing limit is a fundamental issue in cognitive psychology. One particular way of studying it is to adopt a temporal span perspective. In this experiment, Weber fractions based on thresholds for duration discrimination are used for adopting this perspective. The results showed that, contrary to the constant predicted by Weber's law, the Weber fraction is larger at 2 than at .2 s. This increase is observed in conditions where inter-trial intervals and cognitive load are manipulated, and is argued to be due to the fact that 2 s is beyond a temporal span limit for processing information.     

The redux of cognitive consistency theories: evidence judgments by constraint satisfaction

The authors suggest that decisions made from multiple pieces of evidence are performed hy mechanisms of parallel constraint satisfaction, which are related to cognitive consistency theories. Such reasoning processes are bidirectional--decisions follow from evidence, and evaluations of the evidence shift toward coherence with the emerging decision. Using a factually complex legal case, the authors observed patterns of coherence shifts that persisted even when the distribution of decisions was manipulated (Study 1) and influenced by the participants' attitudes (Study 2). The evaluations of the evidence cohered with the preferred decision even when participants changed their preference (Study 3). Supporting the bidirectionality of reasoning. Study 4 showed that assigning participants to a verdict affected their evaluation of the evidence. Coherence shifts were observed also in related background knowledge. This research suggests that cognitive consistency theories should play a greater role in the understanding of human reasoning and decision making.     

Perceptual completion and object-based representations in short-term visual memory

Object-based representations in visual short-term memory (VSTM) were examined using a change detection memory task. A display comprising two rows of four differently colored elements was followed by a probe display in which only one of the rows reappeared. On same trials, the probed row was identical to the corresponding row in the memory display. On different trials, two of the elements in the probed row had their colors exchanged. In each memory display, a task-irrelevant visual element appeared between the two rows, with the potential to function as an occluder. Performance was enhanced when perceptual completion meant that four, rather than eight, objects were perceived in the memory display and when the probe display revealed that the occluded elements continued behind the occluder. It appears that several forms of representation can co-occur to support VSTM, one of which is object based.     

What you get out of memory depends on the question you ask

Following study, participants received 2 tests. The 1st was a recognition test; the 2nd was designed to tap recollection. The objective was to examine performance on Test 1 conditional on Test 2 performance. In Experiment 1, contrary to process dissociation assumptions, exclusion errors better predicted subsequent recollection than did inclusion errors. In Experiments 2 and 3, with alternate questions posed on Test 2, words having high estimates of recollection with one question had high estimates of familiarity with the other question. Results supported the following: (a) the 2-test procedure has considerable potential for elucidating the relationship between recollection and familiarity; (b) there is substantial evidence for dependency between such processes when estimates are obtained using the process dissociation and remember-know procedures; and (c) order of information access appears to depend on the question posed to the memory system.     

Phonology competes with syntax: experimental evidence for the interaction of word order and accent placement in the realization of Information Structure

In this paper, we investigate the interaction of phonological and syntactic constraints on the realization of Information Structure in Greek, a free word order language. We use magnitude estimation as our experimental paradigm, which allows us to quantify the influence of a given linguistic constraint on the acceptability of a sentence. We present results from two experiments. In the first experiment, we focus on the interaction of word order and context. In the second experiment, we investigate the additional effect of accent placement and clitic doubling. The results show that word order, in contrast to standard assumptions in the theoretical literature, plays only a secondary role in marking the Information Structure of a sentence. Order preferences are relatively weak and can be overridden by constraints on accent placement and clitic doubling. Our experiments also demonstrate that a null context shows the same preference pattern as an all focus context, indicating that 'default' word order and accent placement (in the absence of context) can be explained in terms of Information Structure. In the theoretical part of this paper, we formalize the interaction of syntactic and phonological constraints on Information Structure. We argue that this interaction is best captured using a notion of grammatical competition, such as the one developed by Optimality Theory (Prince & Smolensky, 1993, Optimality theory: constraint interaction in generative grammar (Technical Report No. 2). Center for Cognitive Science, Rutgers University, Piscataway, NJ; Science 275 (1997) 1604). In particular, we exploit the optimality theoretic concept of constraint ranking to account for the fact that some constraint violations are more serious than others. We extend standard Optimality Theory to obtain a grammar model that predicts not only the optimal (i.e. grammatical) realization of a given input, but also makes predictions about the relative grammaticality of suboptimal structures. This allows us to derive a constraint hierarchy that accounts for the interaction of phonological and syntactic constraints on Information Structure and models the acceptability patterns found in the experimental data.     

Remote delivery of cognitive science laboratories: A solution for small disciplines in large countries

Numerically small disciplines can be jeopardized by geographic difficulties, if student populations at universities are small and distances between them large. This problem could be addressed, if teaching resources could be shared among several universities and students in several locations could be taught simultaneously. We present the results of a trial in simultaneous Internet and videoconferencing delivery of an introductory cognitive science laboratory. The trial relied on off-the-shelf software and hardware. Students found the delivery nearly as effective as a locally run laboratory, despite a noticeable difference in the level of interactivity between the remote and other, local laboratory classes. We discuss possible further improvements in teaching efficiency and efficacy.     

Falsifying mental models: Testing the predictions of theories of syllogistic reasoning

Four experiments are reported that tested the claim, drawn from mental models theory, that reasoners attempt to construct alternative representations of problems that might falsify preliminary conclusions they have drawn. In Experiment 1, participants were asked to indicate which alternative conclusion(s) they had considered in a syllogistic reasoning task. In Experiments 2-4, participants were asked to draw diagrams consistent with the premises, on the assumption that these diagrams would provide insights into the mental representation being used. In none of the experiments was there any evidence that people constructed more models for multiple-model than for single-model syllogisms, nor was there any correlation between number of models constructed and overall accuracy. The results are interpreted as showing that falsification of the kind proposed by mental models theory may not routinely occur in reasoning.