Recency effects as a window to generalization: separating decisional and perceptual sequential effects in category learning

Accounts of learning and generalization typically focus on factors related to lasting changes in representation (i.e., long-term memory). The authors present evidence that shorter term effects also play a critical role in determining performance and that these recency effects can be subdivided into perceptual and decisional components. Experimental results based on a probabilistic category structure show that the previous stimulus exerts a contrastive effect on the current percept (perceptual recency) and that responses are biased toward or away from the previous feedback, depending on the similarity between successive stimuli (decisional recency). A method for assessing these recency effects is presented that clarifies open questions regarding stimulus generalization and perceptual contrast effects in categorization and in other domains.     

Parameterization of movement execution in children with developmental coordination disorder

The Rhythmic Movement Test (RMT) evaluates temporal and amplitude parameterization and fluency of movement execution in a series of rhythmic arm movements under different sensory conditions. The RMT was used in combination with a jumping and a drawing task, to evaluate 36 children with Developmental Coordination Disorder (DCD) and a matched control group. RMT errors in space and in time were significantly larger for children with DCD. Omission of sensory information decreased the accuracy of movement parameterization in children with DCD more than in the control group, suggesting that children with DCD have more problems in building up an internal representation of the movement. Errors in time correlated significantly with the jumping and drawing task, while errors in space did not. Deficits of temporal movement parameterization might be one of the underlying causes of poor motor performance in some children with DCD.     

The importance of an evidence-based approach in the current Spanish policy for crime prevention

This introductory paper has two objectives. On the one hand, to present the guidelines of the evidence-based perspective on crime prevention as an alternative to the usual criminal policy, which often disregards conclusions based on scientific evidence. On the other hand, to discuss the contemporary situation in Spain regarding crime prevention and particularly the role psychology develops in terms of the utility/effectiveness dichotomy. The evidence-based perspective on crime prevention is guided by the main criteria of collecting the best scientific evidence in relation to 'what works best' in the different areas of crime prevention. In that purpose systematic reviews and meta-analyses are strongly recommended. The Campbell Collaboration in Crime and Justice is a scientific endeavour oriented to prepare rigorous and systematic reviews of high-quality evidence about 'what works'. Regarding crime prevention in Spain it is argued that psychology and other disciplines must make society and its rulers see that intervention based on evidence-based policy is essential for crime prevention.     

Is retrieval success a necessary condition for retrieval-induced forgetting?

When information is retrieved from memory, it becomes more recallable than it would have been otherwise. Other information associated with the same cue or configuration of cues, however, becomes less recallable. Such retrieval-induced forgetting (Anderson, Bjork, &; Bjork, 1994) appears to reflect the suppression of competing nontarget information, with this suppression facilitating the selection of target information. But is success at such selection a necessary condition for retrieval-induced forgetting? Using a procedure in which some cues posed an impossible retrieval task for participants, we report evidence that the attempt to retrieve, even if unsuccessful, can produce retrieval-induced forgetting. This finding, we believe, supports and refines a suppression/inhibitory account of retrieval-induced forgetting.     

The effects of spatial stimulus-response compatibility on choice time production accuracy and variability

Five experiments examined the relations between timing and attention using a choice time production task in which the latency of a spatial choice response is matched to a target interval (3 or 5 s). Experiments 1 and 2 indicated that spatial stimulus-response incompatibility increased nonscalar timing variability without affecting timing accuracy and that choice reaction time practice reduced choice time production variability. These data support a "temporal discounting" model in which response choice and timing occur in series, but the interval timed is shortened to account for nontemporal processing. In Experiment 3, feedback and anticipation task demands improved choice time production accuracy. In Experiments 4 and 5, the delay between the start-timing and choice-decision signals interacted with choice difficulty to affect choice time production accuracy and variability when timing a 3- but not a 5-s interval, suggesting that attention mediates timing before and after an interruption in timing.     

The effects of aging on time reproduction in delayed free-recall

The experiments presented here demonstrate that normal aging amplifies differences in time production occurring in delayed free-recall testing. Experiment 1 compared the time production ability of two healthy aged groups as well as college-aged participants. During the test session, which followed a 24-h delay and omitted all feedback and examples of the two target intervals, the two groups of aged participants' over-produced a 6s interval. This effect is similar in form to errors shown by young participants, but twice the magnitude. Productions of a 17 s interval were generally accurate overall. However, further analysis indicated that the majority of aged participants over-produced the 17 s interval while a minority greatly under-produced the 17 s interval. Furthermore, aged participants showed violations of the scalar property of timing variability in the training session, while in the test session, only those who under-produced the 17 s interval showed this tendency. In contrast, training session performance was good for all participants. Experiments 2 and 3 investigated the ability of the participants in Experiment 1 to reproduce the length of a line from memory, under conditions analogous to those of the time production experiments. These experiments provided tests of the specificity of the errors observed in Experiment 1. Performance in the older participants was accurate, if more variable, compared to the young participants, in contrast to the time production results, indicating that production inaccuracy in free-recall is specific to interval timing in the current context.     

The influence of referential discourse context on modifier attachment in Dutch

In an eye-tracking experiment we investigated the influence of referential context on the attachment of a relative clause to two possible hosts (as in "Someone shot the servant of the actress who was on the balcony"). The attachment of the relative clause was disambiguated grammatically at the first word after the onset of the ambiguity in order to investigate immediate effects of discourse. The contexts had been verified in a sentence completion study to make sure that they induced a strong bias toward early or late closure. The results of the reading experiment, however, revealed no significant interaction of referential context with the attachment preference of the relative clause. The only robust and consistent effect we found was a preference for early closure, independent of the preceding context. These data favor accounts positing that referential context does not influence the initial attachment decision, but does play a role in later phases of sentence processing.     

Mother-child separations among homeless and housed families receiving public assistance in New York City

We examined the incidence, characteristics, and predictors of separations of children from mothers in 543 poor families receiving public assistance, 251 of whom had experienced homelessness during the previous 5 years. Forty-four percent of the homeless mothers and 8% of housed mothers were separated from one or more children. A total of 249 children were separated from 110 homeless families and 34 children from 23 housed families. Children were placed with relatives and in foster care but were rarely returned to their mothers. Maternal drug dependence, domestic violence, and institutionalization predicted separations, but homelessness was the most important predictor, equivalent in size to 1.9 other risk factors. We infer that policies regarding child welfare and substance abuse treatment should be changed to reduce unnecessary placements. Studies of homeless children who remain with families may be biased if separated children are excluded.     

Phonological, semantic, and repetition priming with homophones

The current study investigated semantic, repetition, and phonological priming using heterographic homonyms (homophones) as stimuli in a lexical decision task. As in previous research, reliable semantic priming and repetition effects were found. In addition, the statistical additivity of these two effects was replicated using homophones as stimuli. Using homophones, a reliable phonological priming effect was found when 10-16 intervening trials were used. This effect was also statistically independent of semantic priming indicating the independence of the mechanisms responsible for semantic and phonological priming. The magnitude of the phonological priming effect was also significantly less than the magnitude of the repetition effect. This difference in effect magnitude was taken to indicate that the repetition of phonological information is not a primary contributor to the repetition effect.