Limits of the retrieval-inhibition construct: list segregation in directed forgetting

The authors hypothesized that retrieval inhibition in list method directed forgetting could be improved by presenting a task that maximized the segregation step of the retrieval-inhibition process. In Experiment 1, they presented lists of semantically related words in a list method directed-forgetting task to maximize retrieval inhibition. Contrary to predictions, this manipulation eliminated the directed-forgetting effect. The authors further investigated the results of Experiment 1 in Experiments 2 and 3 by manipulating recall instructions and by presenting lists that contained both a categorized and an unrelated list-half. They found directed-forgetting effects for semantically related word lists when participants were asked to recall only the TBR (to-be-remembered) items but not when participants were asked to recall both the TBF (to-be-forgotten) and TBR items. They also found that directed-forgetting effects were not produced when categorized items were presented in the 1st list.     

Social dominance and ethical ideology: the end justifies the means?

Although many social psychological researchers have tried to identify the antecedents of unethical or immoral behavior, investigators have little considered the content of ethical beliefs that associate with important personality variables such as authoritarianism (B. Altemeyer, 1981, 1996) and social dominance orientation (SDO; J. Sidanius, 1993). Previous studies suggest that authoritarianism is associated with the rejection of relativistic standards for moral actions and--to a lesser extent--the idealistic belief that moral actions should not harm others (J. W. McHoskey, 1996). In the present study, 160 New Zealand University students completed measures of SDO (J. Sidanius), Right Wing Authoritarianism (RWA, B. Altemeyer, 1981), and two subscales of ethical ideology: Relativism and Idealism (D. R. Forsyth, 1980). As expected, SDO showed a negative relationship with Idealism, a belief that actions should not harm others. But, contrary to expectations, SDO showed no consistent association with relativism, a belief that the moralities of actions are not comparable. On the basis of those findings, people with high SDO might be described as "ruthless" in their pursuit of desirable goals and are indifferent about whether the morality of different actions can be compared or even matter.     

Location, location, location: the misprediction of satisfaction in housing lotteries

People tend to overestimate the emotional consequences of future life events, exhibiting an impact bias. The authors replicated the impact bias in a real-life context in which undergraduates were randomly assigned to dormitories (or "houses"). Participants appeared to focus on the wrong factors when imagining their future happiness in the houses. They placed far greater weight on highly variable physical features than on less variable social features in predicting their future happiness in each house, despite accurately recognizing that social features were more important than physical features when asked explicitly about the determinants of happiness. In Experiment 2, we found that this discrepancy emerged in part because participants exhibited an isolation effect, focusing too much on factors that distinguished between houses and not enough on factors that varied only slightly, such as social features.     

Procedural learning in children with developmental coordination disorder

Despite the fact that developmental coordination disorder (DCD) is characterised by a deficit in the ability to learn or automate motor skills, few studies have examined motor learning over repeated trials. In this study we examined procedural learning in a group of 10 children with DCD (aged 8-12 years) and age-matched controls without DCD. The learning task was modelled on that of Nissen and Bullemer. Children performed a serial reaction time (SRT) task in which they were required to learn a spatial sequence that repeated itself every 10 trials. Children were not aware of the repetition. Spatial targets were four (horizontal) locations presented on a computer monitor. Children responded using four response keys with the same horizontal mapping as the stimulus. They were tested over five blocks of 100 trials each. The first four blocks presented the same repeating sequence, while the fifth block was randomised. Procedural learning was indexed by the slope of the regression of RT on blocks 1-4. Results showed that most children displayed strong procedural learning of the sequence, despite having no explicit knowledge about it. Overall, there was no group difference in the magnitude of learning over blocks of trials - most children performed within the normal range. Procedural learning for simple sequential movements appears to be intact in children with DCD. This suggests that cortico-striatal circuits that are strongly implicated in the sequencing of simple movements appear to be function normally in DCD.     

British female academics and comparative psychology: attempts to establish a research niche in the early 20th century

Why was there a preponderance of women engaged in laboratory-based studies of animal behavior in Britain in the early years of the 20th century? As a new experimental subject with recently neglected potential, animal psychology then represented an opportunity for women to make further inroads into academic science. Because the study of psychology before World War I offered negligible professional opportunities for the application of the subject, the intake of students was restricted. Perhaps this encouraged academic access to it by aspiring female scientists who felt that career prospects, uncertain and socially unexpected of them in any case, were worth chancing for greater long-term rewards. The academic circumstances and contributions of 3 British female pioneers in experimental comparative psychology are discussed.     

The case for sensorimotor coding in working memory

The highly influential Baddeley and Hitch model of working memory (Baddeley & Hitch, 1974; see also Baddeley, 1986) posited analogical forms of representation that can be broadly characterized as sensorimotor, both for verbal and for visuospatial material. However, difficulties with the model of verbal working memory in particular have led investigators to develop alternative models that avoid appealing either to sensory coding or to motoric coding, or to both. This paper examines the evidence for sensorimotor coding in working memory, including evidence from neuropsychology and from sign language research, as well as from standard working memory paradigms, and concludes that only a sensorimotor model can accommodate the broad range of effects that characterize verbal working memory. In addition, several findings that have been considered to speak against sensorimotor involvement are reexamined and are argued to be in fact compatible with sensorimotor coding. These conclusions have broad implications, in that they support the emerging theoretical viewpoint of embodied cognition.     

Abnormalities of motor and praxis imagery in children with DCD

In an earlier study using the visually guided pointing task (VGPT) the authors showed that the timing of imagined movement sequences in children with developmental coordination disorder (DCD) does not conform to the conventional speed-for-accuracy trade-off (or Fitts' law [P.M. Fitts, Journal of Experimental Psychology 47 (1954) 381-391]) that occurs when the distance and accuracy requirements of movements are varied [P. Maruff, P.H. Wilson, M. Trebilcock, J. Currie, Neuropsychologia 37 (1999b) 1317-1324]. The present study sought to replicate this earlier finding and to examine (using a weight manipulation) whether this deficit was also attributable to inaccurate programming of relative force. The chronometry of real and imagined movements was investigated in a group of 20 children with DCD aged between 8 and 12 years and a group of controls matched on age and verbal IQ (VIQ). Movement duration was tested for real and imagined movements using the preferred hand, with the VGPT performed under two load conditions: with and without the addition of a weight attached to a pen. Group means of each subjects' mean movement duration were calculated and plotted against target width for each of the four conditions [Movement type (2) x Load (2)] and a logarithmic curve was fitted to the data points. In the control group, the speed-for-accuracy trade-off for both real and imagined performance conformed to Fitts' law under each load condition. In the DCD group only real movements conformed to Fitts' law. Moreover, the effect of load differed between groups--for real movements, movement duration did not differ between load and no-load conditions for either group, while for imagined movements, movement duration increased under the load condition for the control group only. These results replicate and extend the results of our earlier study. This pattern of performance suggests that children with DCD have an impairment in the ability to generate internal representations of volitional movements which may reflect an impaired ability to process efference copy signals. The ability to programme both relative force and timing appears to underly this difficulty. Results have implications for the use of (guided) motor imagery training in order to facilitate the development of motor skill in children with DCD.     

Stressful life events and impulsiveness in failed suicide

The relationship of recent stressful life events with impulsiveness in triggering suicide attempts and how impulsiveness changes from one suicide attempt to another is unclear. This study used structured-interview tools and standardized measurements to examine the relationship between life stress and impulsiveness in a sample of patients who required hospitalization for a medically serious suicide attempt. After controlling for potentially confounding variables, the number of disrupted interpersonal relationships in the preceding year was a significant predictor of the impulsiveness of the suicide attempt, with three or more losses (but not other life stresses) associated with less impulsive attempts (T = 2.4, p = .02). Female gender (T = -1.98, p = .05) and lifetime DMS-III-R diagnoses (T = -2.45, p = .02) were significantly associated with more impulsive attempts. In 55 patients with at least two suicide attempts, impulsiveness, lethal intent, and communication of intent were significantly greater for the present compared to the prior attempt (p = 0.000). Certain stressful life events, gender, and total lifetime DSM-III-R diagnoses are associated with impulsiveness of failed suicide attempts; yet, impulsiveness is not necessarily consistent from one suicide attempt to another. This evidence supports and amplifies a stress-diathesis model of suicide behavior. Accordingly, efforts to increase personal resilience in individuals who have "failed suicide" may be more effective at preventing suicide morbidity than simple stress-reduction measures alone.