Covariation detection in treated and untreated spider phobics.

Twenty treated and 18 untreated spider phobics were exposed to a series of 72 slides. Three different categories of slides were used: phobia-relevant slides (spiders), alternative fear-relevant slides (weapons), and neutral slides (flowers). Slides were randomly paired with either a shock, a tone, or nothing at all. Despite the absence of a systematic correlation between slides and outcomes, untreated phobics strongly overestimated the covariation between spider slides and shock. Treated phobics did not show a covariation bias, suggesting that such bias can be modulated by behavioral treatment. In addition, untreated subjects were more confident about their contingency estimates than were treated subjects. The present results fit with earlier studies.     

Is the match/mismatch model based on a statistical artefact?

In the match/mismatch model, recently formulated by Rachman and coworkers, it is stated that incorrectly predicted aversive experiences are generally followed by an immediate adjustment of the predictions concerning aversiveness of the next experience. This model can be considered to reflect a psychological process of the formation of expectations. In the present article it is argued that a simple H0 model, assuming that predictions are completely randomly generated by the subject, may account for the same effects. This H0 model is used in a stringent test of empirical data to determine if there are any effects of the discrepancy between prediction and experience on next prediction that exceed the effects explained by the H0 model. Although the H0 model produces effects very similar to the empirically observed effects, there is clear support for the hypothesized influence of the discrepancy between prediction and experience. Therefore, the model appears to reflect 'real' psychological processes and not chance findings.     

The relationship between underpredicted pain and escape

Escape and avoidance that are disproportional to the danger of the pertinent stimulus are important clinical problems that are often related to inaccurate (catastrophic) expectations. One possible source of such expectations is a prior, underestimated aversive experience. In the present experiment the hypotheses that underestimated pain leads to escape and that it leads to avoidance were tested. In order to control for the effect of the intensity of the pain stimulus, a control group that received 20 pain stimuli of high intensity was formed. Subjects in the experimental condition received 17 pain stimuli of low intensity and 3 of (unexpectedly) high intensity (experimentally induced underprediction). Underprediction of the high intensity stimulus was significantly related to escape, but not to avoidance. The results suggest that the way in which avoidance was operationalized accounts for this. The strong support of the hypothesized relationship between underpredicted pain and escape is an important finding, however.     

A longitudinal study of "intrusion-based reasoning" and posttraumatic stress disorder after exposure to a train disaster

Previously, we found that chronic PTSD relates to “intrusion-based reasoning” (IR), i.e. the tendency to interpret distressing intrusions themselves as evidence that danger is impending, regardless of objective danger information (Engelhard et al., Behav. Res. Ther. 39 (2001) 1139). This study was intended to elucidate the causal status of this relation. Twenty-nine residents of a Belgian town witnessed a train crash and were assessed for IR and PTSD symptoms within 1 month and were re-assessed for PTSD at 3.5 months. Fourteen control residents did not witness the crash and were also tested for IR. The IR paradigm involved rating the danger of brief scenarios in which objective danger and presence of intrusions about the crash were systematically varied. The directly exposed residents showed greater danger ratings to scenarios in which intrusions were included than did the controls. IR was strongly related to both acute and chronic PTSD symptoms. It did not significantly predict chronic PTSD symptoms after controlling for acute symptoms, although the partial correlation (r=0.26, p=0.09) was in the expected direction. The data suggest that IR is involved in the onset and maintenance of PTSD symptoms, but more clarity about causality awaits future larger and experimental studies.     

No evidence for overgeneral memories in borderline personality disorder

The hypothesis that borderline personality disorder (BPD) is related to overgeneral memories was tested in a mixed sample of 39 patients. A memory test with emotional cue words and the instruction to produce specific autobiographical memories was used. Specificity was judged by an independent rater. Regression analyses indicated that age and major depressive disorder were related to the production of less specific memories, whereas educational level and presence of personality disorder were positivily related to number of specific memories. Borderline personality disorder, anxiety disorders and childhood traumas were not related to number of specific memories.     

Beliefs in personality disorders: a test with the personality disorder belief questionnaire

The hypothesis that each personality disorder (PD) is characterized by a specific set of beliefs was tested in a sample of 643 subjects, including non-patient controls, axis-I and axis-II patients, diagnosed with SCID-I and -II interviews. Beliefs of six PDs (avoidant, dependent, obsessive-compulsive, paranoid, histrionic, borderline) were assessed with the Personality Disorder Belief Questionnaire (PDBQ). Factor analyses supported the existence of six hypothesized sets of beliefs. Structural equation modeling (SEM) supported the hypothesis that each PD is characterized by a specific set of beliefs. Path coefficients were however in the medium range, suggesting that PDs are not solely determined by beliefs. Nevertheless, empirically derived cutoff scores of the six belief subscales were reasonably successful in classifying subjects, percentages ranging form 51% to 83%. It appeared that there was a monotonical increase in scores on each belief subscale from non-patient controls, to patients without any PD, to patients with PDs (other than the pertinent PD), to patients with the pertinent PD. This suggests that PD-related beliefs are at least partly associated with (personality) psychopathology in general. Another explanation is that many patients' position on the underlying dimensions is not high enough to lead to a DSM PD diagnosis, but high enough to lead to an elevated belief score.     

Changes in natural language use as an indicator of psychotherapeutic change in personality disorders

Word use has been shown to reflect various psychological processes and psychological change. This study examines the self-view in personality disorders (PDs) and its change over the course of therapy using the Linguistic Inquiry and Word Count analysis procedure. A sample of 299 participants with PDs and 108 community control participants wrote short essays about their lives. Patients repeated the assignment three times over two years and completed assessments of PD-pathology, general psychopathology, PD-beliefs, and quality of life. Results show that as hypothesized the use of words in the 1st Person Singular Pronouns, Negative Emotion, Causation, Past and Future Tense Verbs categories significantly declines over the course of treatment, while the use of Present Tense Verbs and Positive Emotion increases. These categories tend to distinguish patients from non-patients prior to treatment. We also found 12 additional word categories changing over time, including Word Count and Negations. Change in word use statistically predicts better treatment outcome on all outcome measures (p < .001). Reductions in the use of Negative Emotion Words and Negations are the strongest predictors of outcome. The non-hypothesized role of Negations was explored and seemed to reflect that PD-patients miss a lot in their lives. Reduction of what they miss seems central to recovery. This issue seems relatively neglected in theoretical and treatment models of PDs. An increased focus on what patients miss in their lives might improve our understanding and treatment of PDs. In sum, Negative Emotion and Negation word categories appear to reflect key treatment targets.     

Automated verbal credibility assessment of intentions: The model statement technique and predictive modeling

Recently, verbal credibility assessment has been extended to the detection of deceptive intentions, the use of a model statement, and predictive modeling. The current investigation combines these 3 elements to detect deceptive intentions on a large scale. Participants read a model statement and wrote a truthful or deceptive statement about their planned weekend activities (Experiment 1). With the use of linguistic features for machine learning, more than 80% of the participants were classified correctly. Exploratory analyses suggested that liars included more person and location references than truth‐tellers. Experiment 2 examined whether these findings replicated on independent‐sample data. The classification accuracies remained well above chance level but dropped to 63%. Experiment 2 corroborated the finding that liars' statements are richer in location and person references than truth‐tellers' statements. Together, these findings suggest that liars may over‐prepare their statements. Predictive modeling shows promise as an automated veracity assessment approach but needs validation on independent data.