Symbolic Representation by Pigeons

The capacity for symbolic representation is a prerequisite for the development of human language because words, the basic units of language, are symbols that represent things. But symbolic representation may also serve a nonlinguistic role of organizing events into categories having the same meaning, and such a capacity could have considerable survival value for many species. In a number of experiments, my co-workers and I have found that pigeons that are trained to treat two different stimuli similarly also learn that those stimuli are commonly represented and, thus, that they have the same meaning. We have demonstrated evidence for such common representations in a number of ways, but perhaps the most convincing is when pigeons learn a new association involving one of the presumed commonly represented stimuli, and without further training demonstrate that they have learned a similar association involving the other stimulus. Furthermore, we have found that when pigeons are trained to treat two stimuli similarly, one of those stimuli is represented in terms of the other. These results have implications not only for the generality of cognitive processes across species, but also for the generality of symbolic representation beyond language use.     

A comparison of self-report and interview diagnoses of DSM-III-R personality disorders

A total of 73 psychiatric inpatients, all of whom (but two) fulfilled criteria for at least one specific personality disorder (PD) on SCID-II PQ, were interviewed with the help of PDE. The self-report PD diagnosis was confirmed in 35 (48 per cent) patients. The diagnostic agreement between the two instruments was poor, yielding an overall weighted kappa of 0.22. Levelling off the PD base rates by increasing or decreasing the diagnostic threshold of SCID-II PQ and PDE respectively increased the overall weighted kappa to 0.38 in both instances. 70 per cent of SCID-II PQ but only 29 per cent of PDE personality disorders were of extensive type. Most frequent important co-occurrences occurred between individual PD types within cluster 2. On the whole, the results confirmed the relatively poor agreement between self-report and interview PD diagnoses. The utilization of self-report questionnaires in a clinical practice remains a controversial issue. © 1998 John Wiley & Sons, Ltd.     

A comparison of noncontingent reinforcement,other competing stimulation,and liquid rescheduling for the treatment of rumination

Modified versions of three popular nonaversive treatments for rumination in a person with profound developmental delay were evaluated using an alternating treatments design (ATD) as a component of an ABAB design. Results showed that the most effective intervention involved noncontingent feeding every 20 s for the 30 min immediately following a meal. Further analysis demonstrated that no significant increase in rumination occurred during the 60 min after the treatment procedure had expired, thus indicating that rumination was not merely postponed. Results are discussed in terms of their relation to currently popular (satiation) interventions for the treatment of rumination in individuals with developmental disability. Future research needs are proposed from an analysis of known behavioral and physiological variables and their possible interactions. ©1997 by John Wiley & Sons, Ltd.     

Patient-Informed Treatment Development of Behavioral Smoking Cessation for People With Schizophrenia

The objective of this study was to use qualitative methodology to tailor and refine an existing smoking cessation intervention for the population of people who use cigarettes and are diagnosed with schizophrenia, schizoaffective, or psychotic disorder. Successive cohort design methodology was used to iteratively modify the treatment in response to qualitative participant, therapist, and consultant feedback on the intervention. Qualitative methodology for participant feedback included analysis of semistructured interviews with participants, visualization of app utilization data, and stakeholder feedback from study therapists and consultants. Using the successive cohort design, a tailored multicomponent mobile health smoking cessation intervention was developed. The intervention included mobile contingency management (i.e., financial compensation for confirmed abstinence from smoking), pharmacotherapy for smoking cessation, cognitive-behavioral counseling sessions, and the Stay Quit app for relapse prevention. Two cohorts (N = 13) were completed in the study; after each cohort, the treatment protocol was revised. The intervention is described, as well as the qualitative findings from each cohort and subsequent changes made to the intervention based upon patient and provider feedback. Metrics of patient engagement included treatment adherence (40% in Cohort 1 and 63% in Cohort 2). Both participants and therapists reported that the intervention was helpful. Over one third of participants self-reported abstinence at posttreatment. Since qualitative methodology is often underutilized in mental health treatment development, this study demonstrates the utility of the successive cohort design for treatment development of behavior change interventions for at-risk, vulnerable populations.     

A secondary task is not always costly: Context‐based guidance of visual search survives interference from a demanding working memory task

Repeatedly encountering a visual search display with the target located at a fixed position relative to the distractors facilitates target detection, relative to novel displays – which is attributed to search guidance by (acquired) long‐term memory (LTM) of the distractor ‘context’ of the target. Previous research has shown that this ‘contextual cueing’ effect is severely impeded during learning when participants have to perform a demanding spatial working memory (WM) task concurrently with the search task, though it does become manifest when the WM task is removed. This has led to the proposal that search guidance by LT context memories critically depends on spatial WM to become ‘expressed’ in behaviour. On this background, this study, of two experiments, asked: (1) Would contextual cueing eventually emerge under dual‐task learning conditions if the practice on the task(s) is extended beyond the short training implemented in previous studies? and given sufficient practice, (2) Would performing the search under dual‐task conditions actually lead to an increased cueing effect compared to performing the visual search task alone? The answer is affirmative to both questions. In particular, Experiment 1 showed that a robust contextual cueing effect emerges within 360–720 dual‐task trials as compared to some 240 single‐task trials. Further, Experiment 2 showed that when dual‐ and single‐task conditions are performed in alternating trials blocks, the cueing effect for the very same set of repeated displays is significantly larger in dual‐task blocks than in single‐task blocks. This pattern of effects suggests that dual‐task practice eventually leads to direct, or ‘automatic’, guidance of visual search by learnt spatial LTM representations, bypassing WM processes. These processes are normally engaged in single‐task performance might actually interfere with direct LTM‐based search guidance.     

Randomization procedures in single‐case intervention research contexts: (Some of) “the rest of the story”

Following up on articles recently published in this journal, the present contribution tells (some of) “the rest of the story” about the value of randomization in single‐case intervention research investigations. Invoking principles of internal, statistical‐conclusion, and external validity, we begin by emphasizing the critical distinction between design randomization and analysis randomization, along with the necessary correspondence between the two. Four different types of single‐case design‐and‐analysis randomization are then discussed. The persistent negative influence of serially dependent single‐case outcome observations is highlighted, accompanied by examples of inappropriate applications of parametric and nonparametric tests that have appeared in the literature. We conclude by presenting valid applications of single‐case randomization procedures in various single‐case intervention contexts, with specific reference to a freely available Excel‐based software package that can be accessed to incorporate the present randomization schemes into a wide variety of single‐case intervention designs and analyses.     

Dispositional resilience in treatment‐seeking patients with obsessive‐compulsive disorder and its association with treatment outcome

There is a lack of research on the relation between obsessive‐compulsive disorder (OCD) and resilience. Dispositional resilience, as described and defined in literature on hardiness, consists of three facets, namely beliefs about having control in everyday living, having a sense of purpose or commitment, and a positive attitude toward challenges. This study explores associations between dispositional resilience (measured with the Dispositional Resilience Scale (DRS‐15‐R)), symptom severity, and treatment outcome in a sample of 89 patients treated with concentrated exposure therapy (cET), and compares the findings with scores from two reference groups (students and soldiers). The patient group had significantly lower resilience scores than the two reference groups. Weak correlations were observed between dispositional resilience and OCD symptoms. Differences in dispositional resilience were weakly related to remission status at follow‐up (odds ratio of 1.11). Furthermore, resilience improved from pre‐ to post‐treatment (Cohen's d of 0.65). Our results imply that patients’ initial resilience score does not hinder nor facilitate treatment effects to a great extent in this format of ERP treatment.