The cognitive and neural architecture of sequence representation

The authors theorize that 2 neurocognitive sequence-learning systems can be distinguished in serial reaction time experiments, one dorsal (parietal and supplementary motor cortex) and the other ventral (temporal and lateral prefrontal cortex). Dorsal system learning is implicit and associates noncategorized stimuli within dimensional modules. Ventral system learning can be implicit or explicit It also allows associating events across dimensions and therefore is the basis of cross-task integration or interference, depending on degree of cross-task correlation of signals. Accordingly, lack of correlation rather than limited capacity is responsible for dual-task effects on learning. The theory is relevant to issues of attentional effects on learning; the representational basis of complex, sequential skills; hippocampal-versus basal ganglia-based learning; procedural versus declarative memory; and implicit versus explicit memory.     

Serial expertise of rhesus macaques

Here we describe the development of serial expertise in 4 experimentally naive rhesus monkeys that learned, by trial and error, the correct order in which to respond to 3-, 4-, and 7-item lists of arbitrarily selected photographs. The probabilities of guessing the correct sequence on 3-, 4-, and 7-item lists were, respectively, 1/6, 1/24, and 1/5040. Each monkey became progressively more efficient at determining the correct order in which to respond on new lists. During subsequent testing, the subjects were presented with all possible pairs of the 28 items used to construct the four 7-item lists (excluding pairs of items that occupied the same ordinal position in different lists). Subjects responded to pairs from different lists in the correct order 91% of the time on the first trials on which these pairs were presented. These features of subjects' performance, which cannot be attributed to procedural memory, satisfy two criteria of declarative memory: rapid acquisition of new knowledge and flexible application of existing knowledge to a new problem.     

Family transactions and relapse in bipolar disorder

This study examined whether patient symptoms and relatives' affective behavior, when expressed during directly observed family interactions, are associated with the short-term course of bipolar disorder. Twenty-seven bipolar patients and their relatives participated in two 10-minute family interactions when patients were discharged after a manic episode. Results indicated that patients who showed high levels of odd and grandiose thinking during the interactions were more likely to relapse during a 9-month followup period than patients who did not show these symptoms during the family discussions. Relapse was also associated with high rates of harshly critical and directly supportive statements by relatives. Patients' odd thinking and relatives' harsh criticism were significantly more likely to be correlated when patients relapsed (r = .53) than when they did not relapse (r = .12). Results suggest that bipolar patients who show increased signs of residual symptomatology during family transactions during the post-hospital period are at increased relapse risk. The data also suggest that relatives of relapsing patients cope with these symptoms by increasing both positive and negative affective behaviors. Moreover, a bidirectional, interactional relationship between patients' symptoms and relatives' coping style seems to capture best the role of the family in predicting relapse in bipolar disorder.     

A review and update on the practice of evaluating Miranda comprehension

This article summarizes recent developments in constitutional law relevant to the Miranda warning. We describe the origins of the warning, concerns about the use of the Miranda warning, perspectives on the utility of the warning, and the relevance of the warning. We describe how the warning has changed over time, requirements for administering the warning, and procedures that police use in delivering the warning and obtaining confessions. We review case law relevant to "coerced" Miranda waivers and confessions, changes over time in the court's interpretation of what constitutes "coercion," use of the warning with special populations, and the recent focus in case law on individual factors that might impair Miranda comprehension. We review empirical research on factors associated with deficits in Miranda comprehension. We integrate case law rulings and empirical research into suggested approaches to forensic assessment of Miranda comprehension.     

Social Anxiety Disorder in Childhood and Adolescence: Current Status and Future Directions

This paper reviews the current status of research on the phenomenology, etiology, maintenance, assessment, and treatment of childhood and adolescent social anxiety disorder (SAD). Despite being one of the most prevalent disorders of childhood and adolescence, SAD paradoxically stands as one of the least recognized, researched, and treated pediatric disorders. The small treatment outcome literature provides preliminary support to the effectiveness of various forms of cognitive behavior therapy. The majority of studies to date, however, are limited by inadequate control conditions. Other findings include some support for the utility of parental involvement in treatment, significant advancements in outcome measures (e.g., normative comparisons, indices of naturalistic social functioning), and impressive durability of gains for the majority of treatments. Future directions are suggested, including experimental and naturalistic studies of developmental pathways and maintenance factors, the incorporation of positive psychology constructs (e.g., positive emotions, hope, self-control) in treatment and prevention, and the continued delineation of differences between child, adolescent, and adult manifestations of SAD.     

Consistent responses of human mothers to prelinguistic infants: the effect of prelinguistic repertoire size

The salience of infants' vocal and visual cues was examined to evaluate the efficacy of prelinguistic vocalizations to guide adult behavior. A videotape, constructed of brief behavioral episodes from 3 infants with different-sized vocal repertoires, was played to 40 mothers of prelinguistic infants. Playback mothers' responses to the episodes were consistent, demonstrating that preverbal behavior elicits comparable reactions across unfamiliar receivers. The audio and video components of the infants' episodes were then recombined. As the vocal repertoire of the stimulus infants increased, changes in the audio component more often led playback mothers to change responses. Thus, playback mothers used vocalizations as cues as the infants' vocal repertoires became larger.     

Bayesian estimation and testing of structural equation models

The Gibbs sampler can be used to obtain samples of arbitrary size from the posterior distribution over the parameters of a structural equation model (SEM) given covariance data and a prior distribution over the parameters. Point estimates, standard deviations and interval estimates for the parameters can be computed from these samples. If the prior distribution over the parameters is uninformative, the posterior is proportional to the likelihood, and asymptotically the inferences based on the Gibbs sample are the same as those based on the maximum likelihood solution, for example, output from LISREL or EQS. In small samples, however, the likelihood surface is not Gaussian and in some cases contains local maxima. Nevertheless, the Gibbs sample comes from the correct posterior distribution over the parameters regardless of the sample size and the shape of the likelihood surface. With an informative prior distribution over the parameters, the posterior can be used to make inferences about the parameters underidentified models, as we illustrate on a simple errors-in-variables model.We thank David Spiegelhalter for suggesting applying the Gibbs sampler to structural equation models to the first author at a 1994 workshop in Wiesbaden. We thank Ulf Böckenholt, Chris Meek, Marijtje van Duijn, Clark Glymour, Ivo Molenaar, Steve Klepper, Thomas Richardson, Teddy Seidenfeld, and Tom Snijders for helpful discussions, mathematical advice, and critiques of earlier drafts of this paper.     

Hierarchical switching in a multi-dimensional task space

We explored shift costs for a dimensionally organized set of tasks. Task dimensions were type of judgement (numerical vs. spatial) and judgement-to-response mapping (compatible vs. incompatible). Shift costs were determined as the difference in RTs between switch trials and repetitions in a situation in which the kind of task was unpredictable. Shift costs were greatest when the type of judgement was changed. A change in the mapping increased shift costs when the type of judgement remained unchanged, but reduced shift costs when the type of judgement was changed as well. Also, response alternations produced costs when both the type of judgement and SR mapping were unchanged, but reduced shift costs otherwise. In addition to the relation between successive tasks, shift costs were modulated by the specifics of the elementary tasks. The major characteristics of the pattern of shift costs could be accounted for by the hypothesis of a dimensionally organized task space in which hierarchically organized, relative switching operations are performed that affect the highest-level task dimension at which a change is required, and all lower-level dimensions in a first step. In a second step, lower-level dimensions are switched back when no change is required, and then the selected control structure is implemented. Received: 11 December 1997 / Accepted: 6 July 1998