Timing precision in circle drawing does not depend on spatial precision of the timing target

The authors manipulated the width of a timing target in continuous circle drawing to determine whether a more stringent spatial-timing criterion would produce an increase in participants' (N = 30) temporal variability. They also examined the effect of the computational method of determining cycle duration. There was no effect of spatial precision on temporal variability in circle drawing, and tapping and circle drawing were found to use the same criterion. Those findings lend strong support to the earlier view of R. B. Ivry, R. M. Spencer, H. N. Zelaznik, and J. Diedrichsen (2002), who argued that continuous tasks such as circle drawing are timed differently from discrete-like tasks such as tapping. Therefore, the results of the present study provide support for the event and emergent timing frameworks.     

How forgetting aids heuristic inference

Some theorists, ranging from W. James (1890) to contemporary psychologists, have argued that forgetting is the key to proper functioning of memory. The authors elaborate on the notion of beneficial forgetting by proposing that loss of information aids inference heuristics that exploit mnemonic information. To this end, the authors bring together 2 research programs that take an ecological approach to studying cognition. Specifically, they implement fast and frugal heuristics within the ACT-R cognitive architecture. Simulations of the recognition heuristic, which relies on systematic failures of recognition to infer which of 2 objects scores higher on a criterion value, demonstrate that forgetting can boost accuracy by increasing the chances that only 1 object is recognized. Simulations of the fluency heuristic, which arrives at the same inference on the basis of the speed with which objects are recognized, indicate that forgetting aids the discrimination between the objects' recognition speeds.     

Trial order and retention interval in human predictive judgment

The influences of order of trial type and retention interval on human predictive judgments were assessed for a cue that was reinforced on half of its training presentations. Subjects observed 10 cue-outcome presentations (i.e., reinforced trials) and 10 cue-alone presentations (i.e., nonreinforced trials) in one of three different orders: all nonreinforced trials followed by all reinforced trials(latent inhibition), reinforced and nonreinforced trials interspersed (partial reinforcement), or al lreinforced trials followed by all nonreinforced trials (extinction). Ratings were based mainly on the most recent event type (i.e., a recency effect) when the test occurred immediately after training but were based mainly on initial event types (i.e., a primacy effect) when the test occurred after a 48-h delay. The subjects tested both immediately and with a long retention interval did not exhibit this shift to primacy (i.e., the recency effect persisted). These results demonstrate noncatastrophic forgetting and the flexible use of trial order information in predictive judgments.     

What underlies the neuropsychological pattern of irregular > regular past-tense verb production?

The disadvantage in producing the past tense of regular relative to irregular verbs shown by some patients with non-fluent aphasia has been alternatively attributed (a) to the failure of a specific rule-based morphological mechanism, or (b) to a more generalised phonological impairment that penalises regular verbs more than irregular owing to the on-average greater phonological complexity of regular past-tense forms. Guided by the second of these two accounts, the current study was designed to identify more specific aspects of phonological deficit that might be associated with the pattern of irregular > regular past-tense production. Non-fluent aphasic patients (N = 8) were tested on past-tense verb production tasks and assessed with regard to the impact of three main manipulations in other word-production tasks: (i) insertion of a delay between stimulus and response in repetition; (ii) presence/number of consonant clusters in a target word in repetition; (iii) position of stress within a bi-syllabic word in repetition and picture naming. The performance of all patients deteriorated in delayed repetition; but the patients with the largest discrepancy between regular and irregular past-tense production showed greater sensitivity to the other two manipulations. The phonological nature of the factors that correlated with verb-inflection performance emphasises the role of a phonological deficit in the observed pattern of irregular > regular.     

Witnessing interparental psychological aggression in childhood: implications for daily conflict in adult intimate relationships

We examined the consequences of witnessing interparental psychological aggression in childhood for daily conflict processes in adult intimate relationships. Both partners in 73 heterosexual couples provided daily diary reports of relationship conflict over a 28-day period. Partners' reports of witnessing mother-to-father and father-to-mother psychological aggression were used to predict exposure to daily relationship conflicts and reactivity to those conflicts (as reflected in end-of-day anger). Results showed no evidence of exposure effects: Witnessing interparental psychological aggression was unrelated to the number of conflict days reported by either partner. Reactivity effects emerged for males only, with father's aggression predicting increased reactivity and mother's aggression predicting the opposite. However, we found evidence of direct or unmediated effects of interparental conflict on daily anger for both males and females. Mirroring the reactivity pattern, the same-sex parent's psychological aggression predicted greater daily anger, whereas the opposite-sex parent's aggression predicted less daily anger. These effects emerged independently of Big Five measures of personality; moreover, Big Five measures did not predict outcomes independently of interparental aggression.     

Reactive aggression in boys with disruptive behavior disorders: behavior,physiology, and affect

This study examined responses to peer provocation in boys ages 9–13 years who met symptomatic criteria for ADHD-only, ODD/CD-only, comorbid ADHD/ODD/CD, or no diagnosis. Boys participated in a reaction-time game that included standardized verbal and behavioral provocation. Their behavioral, physiological, and affective responses to this task were measured. Results showed that groups did not differ following high levels of provocation because all boys behaved aggressively. However, following low provocation boys with comorbid ADHD/ODD/CD had higher levels of behavioral aggression, had greater heart rate acceleration, and were rated as angrier than all other boys. In addition, boys with comorbid ADHD/ODD/CD held a grudge longer than other children. Results suggest that boys with comorbid ADHD/ODD/CD are especially reactive to provocation from their peers.     

When objects lose their meaning: what happens to their use?

The 8 patients involved in this study were impaired on tests assessing knowledge of objects and on the demonstration of their use. The patients' success in object use was significantly correlated with their knowledge about the objects, providing further evidence that conceptual knowledge plays a key role in object use. Having a recipient present improved performance in the moderately impaired patients, suggesting that a certain level of conceptual knowledge must remain for the additional information to be beneficial. Although overall accuracy in using the target objects was not related to our measures of affordance, the specific aspects of use afforded by the objects' structures were relatively impervious to semantic impairment, suggesting a role for affordance information when object-specific knowledge is disrupted. The patients' familiarity with the objects was an important predictor of performance. Finally, despite good performance on tests of mechanical problem solving, the patients showed very little evidence of employing these skills in their interactions with real objects.     

A magnetic resonance imaging study of regional cortical volumes following stereotactic anterior cingulotomy

The purpose of this study was to test the hypothesis that orbitofrontal cortical volume would be reduced following anterior cingulotomy for obsessive-compulsive disorder (OCD). Whole brain cortical parcellation was performed on magnetic resonance imaging (MRI) data from nine patients, before and 9 (+/-6) months following anterior cingulotomy. No significant volumetric reductions were found in the orbitofrontal cortex. Exploratory findings of reduced volume in ventral temporo-fusiform and posterior cingulate regions were consistent with chance differences, in the face of multiple comparisons. Therefore, though the circumscribed lesions of anterior cingulotomy have recently been associated with corresponding volumetric reductions in the caudate nucleus, no comparable volumetric reductions are evident in cortical territories. Taken together, these results are most consistent with a model of cingulo-striatal perturbation as a putative mechanism for the efficacy of this procedure. While limitations in sensitivity may have also contributed to these negative findings, the methods employed have previously proven sufficient to detect cortical volumetric abnormalities in OCD. The current results may reflect a relatively diffuse pattern of cortico-cortical connections involving the neurons at the site of cingulotomy lesions. Future functional neuroimaging studies are warranted to assess possible cortical or subcortical metabolic changes associated with anterior cingulotomy, as well as predictors of treatment response.