From sensory processes to conscious perception

In recent years, cognitive neuroscientists have began to explore the process of how sensory information gains access to awareness. To further probe this process, event-related functional magnetic resonance imaging (fMRI) was used while testing subjects with a paradigm known as the "attentional blink." In this paradigm, visually presented information sporadically fails to reach awareness. It was found that the magnitude and time course of activation within the anterior cingulate (BA 32), medial prefrontal cortex (BA 9), and frontopolar cortex (BA 10) predicted whether or not information was consciously perceived during the critical period for the attentional blink. These results are discussed in light of a neural framework for conscious processing.     

Drug treatment of epilepsy: when does it fail and how to optimize its use?

Although modern community-based studies have shown that a majority of people with newly diagnosed epilepsy will enter long-term remission, seizures remain refractory to treatment in a substantial proportion of this population--perhaps as much as 40%. A consensus is being reached that, for operational purposes, pharmacoresistance can be suspected when two appropriately chosen, well-tolerated, first-line antiepileptic drugs (AEDs) or one monotherapy and one combination regimen have failed due to lack of efficacy. Poor prognostic factors include lack of response to the first AED, specific syndromes, symptomatic etiology, family history of epilepsy, psychiatric comorbidity, and high frequency of seizures. These observations suggest that prognosis can often be determined early in the course of the disorder. We propose a management paradigm that aims to maximize the chance of successful AED therapy, including the early use of "rational polytherapy" for patients not responding to monotherapy, and to identify efficiently patients suitable for "curative" resective surgery, in particular those with mesial temporal lobe epilepsy. An orderly approach to each epilepsy syndrome will optimize the chance of perfect seizure control and help more patients achieve a fulfilling life.     

Early manifestations of personality and adult emotional functioning

Developmental antecedents to adult emotional functioning were investigated in an epidemiologic study using theories of personality and emotion. The authors tested whether different types of adult emotional distress can be linked to childhood personality attributes. Using data from 3,138 children at age 7, measures of 4 childhood personality attributes were developed and validated: Behavioral Inhibition, Distress Proneness, Attention, and Inappropriate Interpersonal Self-Regulation. Sound psychometric properties of these scales are demonstrated by considering the measures across multiple samples and in comparison with established child behavior measures. Emotional distress measures were obtained for 694 of these individuals at age 35. Of the personality attributes, 3 of 4 (except behavioral inhibition) predicted general levels of distress as well as specific aspects of adult emotional functioning.     

Adjustment to chronic low back pain--the relative influence of fear-avoidance beliefs, catastrophizing, and appraisals of control

The present study investigated the relative extent to which patients' adjustment to chronic low back pain (CLBP) was influenced by their fear-avoidance beliefs, their tendency to catastrophize, and their appraisals of control. Eighty-three CLBP patients completed a series of self-report measures before participating in a physical therapist-led intervention. Hierarchical multiple regression analyses revealed that patients' perceptions of their ability to decrease pain explained a small, but statistically significant, proportion of the variance in pain intensity. In addition, patients' levels of catastrophizing, as well as their fear-avoidance beliefs about both work and physical activity, were independently associated with levels of disability. Interestingly, however, when exploring the relative predictive utility of these three psychological factors, it became evident that fear-avoidance beliefs about physical activity (FABs-PA) were the only significant predictor of patients' disability. Specifically, those patients who exhibited higher levels of FABs-PA tended to report greater levels of disability, even after adjusting for age, sex and pain intensity.     

Implicit leadership theories in applied settings: factor structure, generalizability, and stability over time

The present empirical investigation had a 3-fold purpose: (a) to cross-validate L. R. Offermann, J. K. Kennedy, and P. W. Wirtz's (1994) scale of Implicit Leadership Theories (ILTs) in several organizational settings and to further provide a shorter scale of ILTs in organizations; (b) to assess the generalizability of ILTs across different employee groups, and (c) to evaluate ILTs' change over time. Two independent samples were used for the scale validation (N1 = 500 and N2 = 439). A 6-factor structure (Sensitivity, Intelligence, Dedication, Dynamism, Tyranny, and Masculinity) was found to most accurately represent ELTs in organizational settings. Regarding the generalizability of ILTs, although the 6-factor structure was consistent across different employee groups, there was only partial support for total factorial invariance. Finally, evaluation of gamma, beta, and alpha change provided support for ILTs' stability over time.     

An application of item response theory analysis to alcohol, cannabis, and cocaine criteria in DSM-IV

Item response theory (IRT) is supplanting classical test theory as the basis for measures development. This study demonstrated the utility of IRT for evaluating DSM-IV diagnostic criteria. Data on alcohol, cannabis, and cocaine symptoms from 372 adult clinical participants interviewed with the Composite International Diagnostic Interview--Expanded Substance Abuse Module (CIDI-SAM) were analyzed with Mplus (B. Muthen & L. Muthen, 1998) and MULTILOG (D. Thissen, 1991) software. Tolerance and legal problems criteria were dropped because of poor fit with a unidimensional model. Item response curves, test information curves, and testing of variously constrained models suggested that DSM-IV criteria in the CIDI-SAM discriminate between only impaired and less impaired cases and may not be useful to scale case severity. IRT can be used to study the construct validity of DSM-IV diagnoses and to identify diagnostic criteria with poor performance.     

The redux of cognitive consistency theories: evidence judgments by constraint satisfaction

The authors suggest that decisions made from multiple pieces of evidence are performed hy mechanisms of parallel constraint satisfaction, which are related to cognitive consistency theories. Such reasoning processes are bidirectional--decisions follow from evidence, and evaluations of the evidence shift toward coherence with the emerging decision. Using a factually complex legal case, the authors observed patterns of coherence shifts that persisted even when the distribution of decisions was manipulated (Study 1) and influenced by the participants' attitudes (Study 2). The evaluations of the evidence cohered with the preferred decision even when participants changed their preference (Study 3). Supporting the bidirectionality of reasoning. Study 4 showed that assigning participants to a verdict affected their evaluation of the evidence. Coherence shifts were observed also in related background knowledge. This research suggests that cognitive consistency theories should play a greater role in the understanding of human reasoning and decision making.     

Actor-observer differences in realism in confidence and frequency judgments

Taking a social psychological approach to metacognitive judgments, this study analyzed the difference in realism (validity) in confidence and frequency judgments (i.e., estimates of overall accuracy) between one's own and another person's answers to general knowledge questions. Experiment 1 showed that when judging their own answers, compared with another's answers, the participants exhibited higher overconfidence, better ability to discriminate correct from incorrect answers, lower accuracy, and lower confidence. However, the overconfidence effect could be attributable to the lowest level of confidence. Furthermore, when heeding additional information about another's answers the participants showed higher confidence and better discrimination ability. The overconfidence effect of Experiment 1 was not found in Experiment 2. However, the results of Experiment 2 were consistent with Experiment 1 in terms of discrimination ability, confidence, and accuracy. Finally, in both experiments the participants gave lower frequency judgments of their own overall accuracy compared with their frequency judgments of another person's overall accuracy.     

Space- and object-based attention depend on motor intention

The authors investigated the impact of different motor demands on space- and object-based attention allocation. Responses to targets were either lifting a finger, or pointing to the target, or grasping a clay object placed on the target location. Reaction times and movement times were recorded to assess covert and overt attention, respectively. Both reaction times and movement times showed more space-based attention for pointing than for finger lifting and more object-based attention for grasping than for pointing. That result supports the view that visual selectivity is tuned to specific motor intentions (H. Bekkering & F. W. Neggers, 2002) and illustrates the tight coupling of perception and action.     

Measurements of auditory-verbal STM span in aphasia: effects of item, task, and lexical impairment

In the first part of this study, we investigated effects of item and task type on span performance in a group of aphasic individuals with word processing and STM deficits. Group analyses revealed significant effects of item on span performance with span being greater for digits than for words. We also investigated associations between subjects' lexical-semantic and phonological processing abilities and performance on four measures of verbal span (digit and word span, each varied for type of response, verbal vs. pointing) as well as one measure of nonverbal span. We predicted and found that the patterns of association between verbal span tasks and lexical abilities reflected the integrity of language processes and representations deployed in each paradigm used to assess span. Performance on the pointing span task, which engages both lexical-semantic and phonological processes, correlated with measures of both lexical-semantic and phonological abilities. Performance on repetition span, which engages primarily input and output phonological processes, correlated with measures of phonological abilities but not measures of lexical-semantic abilities. However, when partial correlations were performed for two subject groups based on their relative preservation of lexical-semantic ability (less or more than phonological ability), repetition span correlated with lexical-semantic measures only in the subgroup with relatively impaired lexical-semantics. Additionally, performance on the nonverbal span task correlated with measures of phonological abilities, suggesting either a general cognitive deficit affecting verbal and nonverbal STM or possibly, the use of a verbal strategy to perform this task. Our discussion focuses on the interpretation of span measurements in clinical practice and research, as well as the implications of these data for theories of short-term memory and word processing.