Intentions determine the effect of invisible metacontrast-masked primes: evidence for top-down contingencies in a peripheral cuing task

In 5 experiments, the authors tested whether the processing of nonconscious spatial stimulus information depends on a prior intention. This test was conducted with the metacontrast dissociation paradigm. Experiment 1 demonstrated that masked primes that could not be discriminated above chance level affected responses to the visible stimuli that masked them. Experiments 2 and 3 showed that this effect was abolished when the task instruction was changed in such a way that the primes ceased to be task relevant. Experiments 4 and 5 demonstrated that a prime's effect depended on whether it was associated with the same response as the target or with an opposite response.     

Negative priming effects in children engaged in nonspatial tasks: evidence for early development of an intact inhibitory mechanism

Three experiments are reported that examined conceptual negative priming effects in children 5 to 12 years of age. Experiment 1 used a negative priming variant of a flanker task requiring the naming of a central color blob flanked by irrelevant distractors. Experiment 2 used a negative priming variant of the Stroop color-word task. Experiment 3 used a same-different matching task with novel 3-D shapes. Results revealed significant and equivalent magnitudes of negative priming across the tested age groups for all 3 tasks. It is concluded that the inhibitory mechanism underlying conceptual (i.e., identity or semantic) negative priming in visual selective attention tasks is intact in young children. Because the findings and conclusions diverge from the developmental literature on negative priming, the authors attempt to reconcile the contradictions by pinning down the reasons for the discrepancies.     

Psychopathy and comorbidity in a young offender sample: taking a closer look at psychopathy's potential importance over disruptive behavior disorders

The authors examined the construct of psychopathy as applied to 130 adolescent offenders using 3 psychopathy measures and a broad range of DSM-TV Axis I diagnoses and psychosocial problems. Measures used in the study included the following: (a) Psychopathy Checklist-Youth Version, (b) Antisocial Process Screening Device, (c) a modified version of the Self-Report Psychopathy-II scale, and (d) the Adolescent Psychopathology Scale. Results from this study offer incremental support for the construct validity of psychopathy in youth. Psychopathy evidenced better convergent and discriminant validity results than did the disruptive behavior disorders (DBDs) such as oppositional-defiant disorder (ODD) and conduct disorder (CD). Despite this finding, psychopathy scales nonetheless correlated with other forms of psychopathology at a higher rate than was expected, suggesting that comorbidity is high even when psychopathy is used as a classification scheme. Also, hierarchical multiple regression was used to determine whether psychopathy offered an improvement in the prediction of previous violent and nonviolent offenses. The results for the current study were mixed, with only the PCL-YV significantly predicting previous violent and nonviolent offenses beyond the DBDs. The findings indicate that psychopathy may offer incremental improvement over DBDs with regard to level of comorbidity and perhaps even prediction. However, simply extending the adult construct of psychopathy to youth without considering the array of psychopathology that may accompany adolescent psychopathy could be misleading.     

Predicting risk sensitivity in humans and lower animals: risk as variance or coefficient of variation

This article examines the statistical determinants of risk preference. In a meta-analysis of animal risk preference (foraging birds and insects), the coefficient of variation (CV), a measure of risk per unit of return, predicts choices far better than outcome variance, the risk measure of normative models. In a meta-analysis of human risk preference, the superiority of the CV over variance in predicting risk taking is not as strong. Two experiments show that people's risk sensitivity becomes strongly proportional to the CV when they learn about choice alternatives like other animals, by experiential sampling over time. Experience-based choices differ from choices when outcomes and probabilities are numerically described. Zipf's law as an ecological regularity and Weber's law as a psychological regularity may give rise to the CV as a measure of risk.     

Decision-making impairments in patients with Parkinson's disease

A high percentage of Parkinson's disease (PD) patients show cognitive impairments in addition to the cardinal motor symptoms. These deficits primarily concern executive functions most probably linked to dysfunctions in prefrontal regions due to decreased dopaminergic transmission in fronto-striatal loops. To investigate possible associations between decision-making and executive functions in PD, we examined 20 non-demented PD patients and 20 healthy control subjects with a neuropsychological test battery and the Game of Dice Task. In this computerised decision-making task, the rules for gains and losses and the winning probabilities are obvious and stable. Thus, strategic components besides feedback processing might influence decision-making in this task. We found that PD patients were impaired in the Game of Dice task performance and that the frequency of disadvantageous choices correlated with both executive functions and feedback processing. We suggest that decision-making deficits of PD patients in explicit gambling situations might be associated with dysfunctions in two different fronto-striatal loops: the limbic-orbitofrontal-striatal loop, involved in feedback processing, and the dorsolateral prefrontal-striatal loop, involved in executive functions.     

The Koala Fear Questionnaire: a standardized self-report scale for assessing fears and fearfulness in pre-school and primary school children

The Koala Fear Questionnaire (KFQ) is a standardized self-report scale for assessing fears and fearfulness in children aged between 4 and 12 years. The current article presents six studies which examined the reliability and validity of the KFQ. Study 1 (N=108) demonstrated that the visual fear scales of Koala bears as employed in the KFQ are highly comparable to the standard 3-point scales that are used in other childhood fear measures. Study 2 (N=163) provided support for the convergent validity of the KFQ in a sample of 8- to 14-year-old children. That is, the scale correlated substantially with alternative measures of childhood fear and anxiety. Study 3 (N=189) showed that the KFQ possesses good internal consistency and test-retest stability in a group of 8- to 11-year-old children. The results of Studies 4 (N=129) and 5 (N=176) indicated that the KFQ is suitable for children aged 4 to 6 years and demonstrated that the psychometric properties of the scale in younger children are highly similar to those obtained in older children. Study 6 (N=926) showed that the factor structure of the KFQ was theoretically meaningful: although the data clearly pointed in the direction of one factor of general fearfulness, spurs of the commonly found five-factor solution of childhood fear were found in the KFQ. Altogether, the KFQ seems to be a valuable addition to the instrumentarium of clinicians and researchers who are working with fearful and anxious children.     

The nature and treatment of stuttering as revealed by fMRI A within- and between-group comparison

This article reviews some of our recent functional magnetic resonance imaging (fMRI) studies of stuttering. Using event-related fMRI experiments, we investigated brain activation during speech production. Results of three studies comparing persons who stutter (PWS) and persons who do not stutter (PWNS) are outlined. Their findings point to a region in the right frontal operculum (RFO) that was consistently implicated in stuttering. During overt reading and before fluency shaping therapy, PWS showed higher and more distributed neuronal activation than PWNS. Immediately after therapy differential activations were even more distributed and left sided. They extended to frontal, temporal, and parietal regions, anterior cingulate, insula, and putamen. These over-activations were slightly reduced and again more right sided two years after therapy. Left frontal deactivations remained stable over two years of observation, and therefore possibly indicate a dysfunction. After therapy, we noted higher activations in persons who stutter moderately than in those who stutter severely. These activations might reflect patterns of compensation. We discuss why these findings suggest that fluency-inducing techniques might synchronize a disturbed signal transmission between auditory, speech motor planning, and motor areas.

Educational objectives: The reader will learn about and be able to: (1) identify regions of brain activations and deactivations specific for PWS; (2) describe brain activation changes induced by fluency shaping therapy; and (3) discuss the correlation between stuttering severity and brain activation.     

Cross-language positive priming disappears, negative priming does not: Evidence for two sources of selective inhibition

The authors used a unilingual and bilingual primed lexical decision task to investigate priming effects produced by attended and ignored words. In the unilingual experiment, accelerated lexical decisions to probe target words resulted when the word matched the preceding target word, whereas slowed lexical decisions to probe target words resulted when the word matched the preceding ignored nontarget word. In the bilingual (English-Spanish) experiment, between-language, rather than within-language, priming manipulations were used. Although the ignored repetition negative priming effect replicated across languages, cross-language attended repetition positive priming did not. This dissociation of priming effects in the inter- versus intralanguage priming conditions contradicts episodic retrieval accounts of negative priming that deny the existence of selective inhibitory processes. On the other hand, these results support an extension of inhibition-based accounts of negative priming, because they indicate that inhibition can operate at two levels of abstraction--local word and global language--simultaneously.