The precise time course of lexical activation: MEG measurements of the effects of frequency, probability, and density in lexical decision

Visually presented letter strings consistently yield three MEG response components: the M170, associated with letter-string processing (Tarkiainen, Helenius, Hansen, Cornelissen, & Salmelin, 1999); the M250, affected by phonotactic probability, (Pylkk?nen, Stringfellow, & Marantz, 2002); and the M350, responsive to lexical frequency (Embick, Hackl, Schaeffer, Kelepir, & Marantz, 2001). Pylkk?nen et al. found evidence that the M350 reflects lexical activation prior to competition among phonologically similar words. We investigate the effects of lexical and sublexical frequency and neighborhood density on the M250 and M350 through orthogonal manipulation of phonotactic probability, density, and frequency. The results confirm that probability but not density affects the latency of the M250 and M350; however, an interaction between probability and density on M350 latencies suggests an earlier influence of neighborhoods than previously reported.     

Differential effects of manual assisted cognitive behavior therapy in the treatment of recurrent deliberate self-harm and personality disturbance: the POPMACT study

A total of 480 patients were treated in a large, multicenter randomized trial of a brief form of cognitive therapy, manual-assisted cognitive behavior therapy (MACT) versus treatment as usual (TAU) for recurrent deliberate self-harm. Each patient was randomized after a self-harm episode assessed at an accident and emergency center and followed up over 1 year. The main hypothesis tested was that those allocated to MACT would have a lower proportion of self-harm episodes in the succeeding year. A total of 60% of those allocated to MACT had face-to-face treatment and 430 (90%) of all patients had self-harm data recorded after 1 year. Although the results showed no significant difference between those repeating self-harm in the MACT group (39%) compared with the TAU group (46%) (P = 0.20), the treatment was cost effective (10% cheaper than TAU) and the frequency of self-harm episodes was fewer (50%) in the MACT group. A total of nine of 10 patients had some personality disturbance (42% of these with disorder), and for those where information on parasuicide events was collected, the proportion having a repeat episode ranged from 33% to 63% for different personality disorders. Those with BPD were most likely to repeat episodes quickly (mean 89 days for 25% to repeat) with dissocial personality disorder (equivalent mean 384 days) the slowest to repeat. Total costs were significantly greater in those with personality disorder and were reduced in those allocated to MACT; this saving was reversed in those with borderline disorder. On average, MACT appeared to increase the cost of those patients with BPD (BPD) and reduce the cost of those with other personality disorders. It is concluded that MACT has value in preventing self-harm cost effectively but this appears to be confined mainly to those who do not have BPD.     

Childhood maltreatment associated with adult personality disorders: findings from the Collaborative Longitudinal Personality Disorders Study

Adverse childhood experiences such as abuse and neglect are frequently implicated in the development of personality disorders (PDs); however, research on the childhood histories of most PD groups remains limited. In this multisite investigation, we assessed self-reported history of abuse and neglect experiences among 600 patients diagnosed with either a PD (borderline, schizotypal, avoidant, or obsessive-compulsive) or major depressive disorder without PD. Results indicate that rates of childhood maltreatment among individuals with PDs are generally high (73% reporting abuse; 82% reporting neglect). As expected, borderline PD was more consistently associated with childhood abuse and neglect than other PD diagnoses. However, even when controlling for the effect of borderline PD, other PD diagnoses were associated with specific types of maltreatment.     

Gaze-contingent displays: a review.

Gaze-contingent displays (GCDs) attempt to balance the amount of information displayed against the visual information processing capacity of the observer through real-time eye movement sensing. Based on the assumed knowledge of the instantaneous location of the observer's focus of attention, GCD content can be "tuned" through several display processing means. Screen-based displays alter pixel level information generally matching the resolvability of the human retina in an effort to maximize bandwidth. Model-based displays alter geometric-level primitives along similar goals. Attentive user interfaces (AUIs) manage object- level entities (e.g., windows, applications) depending on the assumed attentive state of the observer. Such real-time display manipulation is generally achieved through non-contact, unobtrusive tracking of the observer's eye movements. This paper briefly reviews past and present display techniques as well as emerging graphics and eye tracking technology for GCD development.     

Testing for social learning and imitation in common marmosets, <Emphasis Type="Italic">Callithrix jacchus</Emphasis>, using an artificial fruit

We tested for social learning and imitation in common marmosets using an artificial foraging task and trained conspecific demonstrators. We trained a demonstrator marmoset to open an artificial fruit, providing a full demonstration of the task to be learned. Another marmoset provided a partial demonstration, controlling for stimulus enhancement effects, by eating food from the outside of the apparatus. We thus compared three observer groups, each consisting of four animals: those that received the full demonstration, those that received the partial demonstration, and a control group that saw no demonstration prior to testing. Although none of the observer marmosets succeeded in opening the artificial fruit during the test periods, there were clear effects of demonstration type. Those that saw the full demonstration manipulated the apparatus more overall, whereas those from the control group manipulated it the least of the three groups. Those from the full-demonstration group also contacted the particular parts of the artificial fruit that they had seen touched (localised stimulus enhancement) to a greater extent than the other two groups. There was also an interaction between the number of hand and mouth touches made to the artificial fruit for the full- and partial-demonstration groups. Whether or not these data represent evidence for imitation is discussed. We also propose that the clear differences between the groups suggest that social learning mechanisms provide real benefits to these animals in terms of developing novel food-processing skills analogous to the one presented here.     

Test modality affects source monitoring and event-related potentials

Two experiments investigated the effect of test modality (visual or auditory) on source memory and event-related potentials (ERPs). Test modality influenced source monitoring such that source memory was better when the source and test modalities were congruent. Test modality had less of an influence when alternative information (i.e., cognitive operations) could be used to inform source judgments in Experiment 2. Test modality also affected ERP activity. Variation in parietal ERPs suggested that this activity reflects activation of sensory information, which can be attenuated when the sensory information is misleading. Changes in frontal ERPs support the hypothesis that frontal systems are used to evaluate source-specifying information present in the memory trace.     

Introduction to the special section on structural equation modeling

Structural equation modeling (SEM) is a frequently used data-analytic technique in psychopathology research. This popularity is due to the unique capabilities and broad applicability of SEM and to recent advances in model and software development. Unfortunately, the popularity and accessibility of SEM is matched by its complexities and ambiguities. Thus, users are often faced with difficult decisions regarding a variety of issues. This special section is designed to increase the effective use of SEM by reviewing recently developed modeling capabilities, identifying common problems in application, and recommending appropriate strategies for analysis and evaluation.     

Axis I and axis II disorders as predictors of prospective suicide attempts: findings from the collaborative longitudinal personality disorders study

This study examined diagnostic predictors of prospectively observed suicide attempts in a personality disorder (PD) sample. During 2 years of follow-up, 58 participants (9%) reported at least 1 definitive suicide attempt. Predictors that were examined include 4 PD diagnoses and selected Axis I diagnoses (baseline and course). Multivariate logistic regression analyses indicated that baseline borderline personality disorder (BPD) and drug use disorders significantly predicted prospective suicide attempts. Controlling for baseline BPD diagnosis, proportional hazards analyses showed that worsening in the course of major depressive disorder (MDD) and of substance use disorders in the month preceding the attempt were also significant predictors. Therefore, among individuals diagnosed with PDs. exacerbation of Axis I conditions, particularly MDD and substance use, heightens risk for a suicide attempt.