The adaptive user: an investigation into the cognitive and task constraints on the generation of new methods

When people use a computer application, they have the opportunity to adapt the methods or strategies that they deploy to better fit the demands of the task. In Experiment 1, we demonstrated that the generation of methods is limited by, but not entirely prevented by, the reduced opportunity that is associated with the iterative nature of typical computer-based tasks. In Experiment 2, we demonstrated that the cognitive demands associated with task-related problem solving delay, but do not prevent, the generation of more efficient device strategies. We argue that people are rather good at adapting device strategies to task demands and that previously reported arguments to the contrary are premature.     

Functional neuroanatomy of emotions: A meta-analysis

The application of functional neuroimaging to the study of human emotion has yielded valuable data; however, the conclusions that may be drawn from any one study are limited. We applied novel statistical techniques to the meta-analysis of 106 PET and fMRI studies of human emotion and tested predictions made by key neuroscientific models. The results demonstrated partial support for asymmetry accounts. Greater left-sided activity was observed for approach emotions, whereas neural activity associated with negative/withdrawal emotions was symmetrical. Support was also found for affect program emotion accounts. The activation distributions associated with fear, disgust, and anger differed significantly. These emotions were most consistently associated in activity in regions associated with selective processing deficits when damaged: the amygdala, the insula and globus pallidus, and the lateral orbitofrontal cortex, respectively. In contrast, the distributions for happiness and sadness did not differ. These findings are considered in the context of conceptualizations of the neural correlates of human emotion.     

Category variability, exemplar similarity, and perceptual classification

Experiments were conducted in which observers learned to classify simple perceptual stimuli into low-variability and high-variability categories. Similarities between objects were measured in independent psychological-scaling tasks. The results showed that observers classified transfer stimuli into the high-variability categories with greater probability than was predicted by a baseline version of an exemplar-similarity model. Qualitative evidence for the role of category variability on perceptual classification, which could not be explained in terms of the baseline exemplar-similarity model, was obtained as well. Possible accounts of the effects of category variability are considered in the General Discussion section.     

Perception of coherent motion in random dot displays by pigeons and humans

Pigeons and humans were required to discriminate coherent from random motion in dynamic random dot displays. Coherence and velocity thresholds were determined for both species, and both thresholds were found to be substantially higher for pigeons than for humans. The results are discussed with reference to differences in motion processing in mammals and birds. It is suggested that the inferior motion sensitivity of pigeons can be attributed to poorer spatiotemporal motion integration.     

What is historicism?

“Historicism” has become a ubiquitous and equivocal term. A classification is given here of five separate uses of the term currently in vogue, each provided with a unique qualifying adjective to help keep them distinct. I then offer a few objections to some of the more radical conclusions which have been drawn by proponents of a specific version of historicism, one associated with “postmodernism “. The positions of Rorty and Putnam are contrasted as examples of strong and weak degrees of historicism, respectively.     

Reducing indices of unhappiness among individuals with profound multiple disabilities during therapeutic exercise routines.

A program was developed to reduce indices of unhappiness that accompanied therapeutic exercise routines among people with profound multiple disabilities. Indices of unhappiness were recorded, using an observation system that had been validated through previous research involving happiness-related variables, while support personnel conducted exercises with 3 participants. A multicomponent program was then implemented that involved presenting highly preferred stimuli before, during, and after each exercise session. Results indicated that the program was accompanied by reduced indices of unhappiness for each participant relative to the traditional method of conducting the exercises, although changes in the preferred stimuli used with 1 participant were required before consistent reductions occurred. Results are discussed regarding the importance of reducing unhappiness indices as a means of enhancing aspects of the daily quality of life for people with profound multiple disabilities. Areas for future research are also discussed, focusing on expanding the unhappiness-reduction procedures to other routine events that may occasion indices of unhappiness.     

EFFECTS OF PREFERENCE AND REINFORCER VARIATION ON WITHIN-SESSION PATTERNS OF RESPONDING

We examined correspondence between preference assessment outcome and within‐session patterns of responding in one subject with autism. Responding maintained by a single highly preferred item resulted in a greater total number of responses, a slower decline in within‐session response rates, and a greater proportion of short interresponse times compared to responding maintained by varied moderately preferred (MP) stimuli. Presenting varied MP stimuli within the same session produced greater levels and more sustained responding than presenting those same stimuli individually.     

Specialization of the motor system in infancy: from broad tuning to selectively specialized purposeful actions

In executing purposeful actions, adults select sufficient and necessary limbs. But infants often move goal‐irrelevant limbs, suggesting a developmental process of motor specialization. Two experiments with 9‐ and 12‐month‐olds revealed gradual decreases in extraneous movements in non‐acting limbs during unimanual actions. In Experiment 1, 9‐month‐olds produced more extraneous movements in the non‐acting hand/arm and feet/legs than 12‐month‐olds. In Experiment 2, analysis of the spatiotemporal dynamics of infants’ movements revealed developmental declines in the spatiotemporal coupling of movements between acting and non‐acting arms. We also showed that the degree of specialization in infants’ unimanual actions is associated with individual differences in motor experience and visual attention, indicating the experience‐dependent and broad functional nature of these developmental changes. Our study provides important new insights into motor development: as in cognitive domains, motor behaviours are initially broadly tuned to their goal, becoming progressively specialized during the first year of life.     

“We have no quarrel with you”: Effects of group status on characterizations of “conflict” with an outgroup

In three studies, we examined the effect of intergroup status on group members' tendencies to characterize the ingroup's relationship with an outgroup as conflictual following outgroup action. Findings from all three studies supported the prediction that the intergroup relationship would be characterized as less conflictual when the ingroup had relatively high rather than low status. Consistent with the hypothesis that the effect of status reflects strategic concerns, it was moderated by the perceived relevance of the outgroup's action to intergroup status relations (study 1), it was sensitive to audience (study 2), and it was partially mediated by status management concerns (study 3). The role of strategic, status‐related factors in intergroup relations is discussed. Copyright © 2014 John Wiley & Sons, Ltd.     

QMPE: Estimating Lognormal, Wald, and Weibull RT distributions with a parameter-dependent lower bound

We describe and test quantile maximum probability estimator (QMPE), an open-source ANSI Fortran 90 program for response time distribution estimation.¹ QMPE enables users to estimate parameters for the ex-Gaussian and Gumbel (1958) distributions, along with three “shifted” distributions (i.e., distributions with a parameter-dependent lower bound): the Lognormal, Wald, and Weibull distributions. Estimation can be performed using either the standard continuous maximum likelihood (CML) method or quantile maximum probability (QMP; Heathcote & Brown, in press). We review the properties of each distribution and the theoretical evidence showing that CML estimates fail for some cases with shifted distributions, whereas QMP estimates do not. In cases in which CML does not fail, a Monte Carlo investigation showed that QMP estimates were usually as good, and in some cases better, than CML estimates. However, the Monte Carlo study also uncovered problems that can occur with both CML and QMP estimates, particularly when samples are small and skew is low, highlighting the difficulties of estimating distributions with parameter-dependent lower bounds.