Charting the process of change: A primer on survival analysis

Survival analysis is a powerful and useful technique for understanding qualitative change. This article provides a practical, nontechnical introduction to the use of survival analysis for social scientists. Important issues in using survival analysis are discussed, including research design, data preparation and management, and data analysis. Attendance data from a self-helf organization are used to illustrate common survival analysis tasks such as describing the overall survival and hazard functions, examining covariate effects, and modeling the form of the hazard function over time. An appendix that discusses the strengths and weaknesses of current survival analysis computer programs is included. Editor's note: Edward Seidman served as action editor for this article while serving as Associate Editor for Methodology.I thank William Davidson, Susan Englund, Bruce Rapkin, Kurt Ribisl, and three anonymous reviewers for their helpful comments on earlier drafts. The example data presented here were collected with the support of an NIMH grant (MH37390) awarded to Julian Rappaport and Ed Seidman.     

Naming consistency in Alzheimer''s disease

Although lexical semantic deficits are postulated to play a prominent role in the anomia of Alzheimer's disease, it is unclear whether the primary disturbance is one of lexical access or one of lexical semantic loss. Response consistency on a naming task is one means of evaluating the underlying source of naming impairment. Access dysfunction usually implies variable word-finding difficulty, while a theory of lexical loss predicts that many word names would be consistently unavailable. Nineteen Alzheimer's disease patients were administered a visual confrontation naming task (the Boston Naming Test) on two occasions 6 months apart. Eighty percent of errors occurred consistently at both times; only 20% of errors occurred on only one occasion. Response consistency occurred significantly more often than expected under the assumption of no response consistency. Findings support the hypothesis that anomia in Alzheimer's disease is in part due to a loss of lexical semantic information.     

Role of spatial location in integration of pictorial information across saccades

Identification of a fixated object in a visual display is facilitated by integrating information from a preview of that object in the periphery with information extracted on the subsequent foveal fixation (Pollatsek, Rayner, & Collins, 1984). These experiments investigated the extent to which this integration is dependent on the spatial location of the information remaining constant. Two preview objects were presented in the periphery; Ss fixated that region and named a single target object that appeared in the same spatial location in which one of the two preview objects had been presented. Of primary interest was the facilitative effect when a preview object was identical to the target object as a function of whether they were in the same spatial location. The major finding was that although there was a small effect of switching, there was still a substantial preview benefit even when the location of the identical object switched. In addition, the switching effect did not interact with the level of identity between the preview and target. There was also a preview benefit in conditions in which there were no eye movements and the preview and target objects were at least 5 degrees apart. Thus, the data indicate that the process object identification is relatively insensitive to location information and that object information and location information are coded fairly independently.     

Effects of foveal processing difficulty on the perceptual span in reading: implications for attention and eye movement control

Two experiments were conducted to examine the effects of foveal processing difficulty on the perceptual span in reading. Subjects read sentences while their eye movements were recorded. By changing the text contingent on the reader's current point of fixation, foveal processing difficulty and the availability of parafoveal word information were independently manipulated. In Experiment 1, foveal processing difficulty was manipulated by lexical frequency, and in Experiment 2 foveal difficulty was manipulated by syntactic complexity. In both experiments, less parafoveal information was acquired when processing in the fovea was difficult. We conclude that the perceptual span is variable and attentionally constrained. We also discuss the implications of the results for current models of the relation between covert visual-spatial attention and eye movement control in reading.     

Object identification without foveal vision: Evidence from an artificial scotoma paradigm

The purpose of the present study was to investigate the degree to which foveal information is necessary for object identification. To explore this question, we used an artificial moving scotoma paradigm to eliminate a region of a currently viewed display in real time as a function of eye position. Subjects examined linear arrays of four line drawings of objects while their eye movements were recorded. Immediately following each array, a test probe was presented to test the degree to which the subject had identified those objects. Three conditions were compared, one in which a central foveal scotoma was created, one in which an extrafoveal scotoma was created, and a control condition in which the scotoma was absent. The main result was that identification accuracy was very good, but eye-movement behavior was disrupted when a foveal scotoma was present. These results suggest that foveal information is not necessary but is beneficial for perceptual encoding during object identification; the loss of foveal information can be overcome as long as compensatory extrafoveal processing is possible.     

Accounting for macro-level causation

By a macro-level feature, I understand any feature that supervenes on, and is thus realized in, lower-level features. Recent discussions by Kim have suggested that such features cannot be causally relevant insofar as they are not classically reducible to lower-level features. This seems to render macro-level features causally irrelevant. I defend the causal relevance of some such features. Such features have been thought causally relevant in many examples that have underpinned philosophical work on causality. Additionally, in certain typical biological cases, we conceive of causally relevant features at various compatible levels of analysis. When elaborated, these points make a strong prima facie case for macro-level causal relevance. However, we might abandon both the philosophical guideposts and the corresponding explanatory practice in the special sciences were we convinced that no reflective philosophical account could provide for the causal relevance there supposed. I show that such drastic measures are not necessary, for we can make sense of macro-level causal relevance by drawing on Paul Humphreys' recent work in ways suggested by the concrete examples considered here.Some of the work on this paper was undertaken at the 1991 NEH Summer Seminar on Causality, directed by Paul Humphreys. I wish to thank my fellow participants, and Paul Humphreys, John Tienson, and Terry Horgan for helpful comments on earlier drafts of this paper.     

Cognitive processing therapy for chronic PTSD from childhood sexual abuse: A case study

This paper describes a case of chronic Post-traumatic Stress Disorder (PTSD), as described in the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV, 4th edn; American Psychiatric Association, 1994). The client has a long history of childhood sexual abuse (CSA), as well as repeated sexual victimization as an adult and addiction issues. She presented with significant avoidance symptoms, including a highly restricted range of affect and distinct feelings of detachment from others. These symptoms had been greatly reduced by the end of the 17-week therapy including both individual and group modalities. The paper elaborates on theoretical issues, the Cognitive Processing Therapy model (Resick & Schnicke, 1993) as it was adapted for use with survivors of childhood sexual abuse, the various phases of the therapeutic process, and specific examples of therapeutic change with this particularly complicated case.     

Rational stage-directed therapy: A cognitive experiential system using hypnosis,imagery, cognitive restructuring,and developmental staging

Conclusion Although RSDT is a relatively new form of therapy, we believe there is reason for great optimism regarding the efficacy of the RSDT model. Communications from our colleagues using the model in a variety of settings have been very favorable. We believe the experimental studies that have been conducted on the RSDT model demonstrate that it has generated significantly better outcomes when compared with other therapeutic models and those results obtained from no therapy controls. We think the effectiveness of RSDT has been admirably demonstrated through comprehensive research designs In comparison with outcome studies conducted on other forms of therapy. We look toward the future with optimism as more practitioners begin to use the RSDT model and additional evaluation studies are conducted.     

Lay theories of delinquency

This paper is concerned with the range, structure and determinants of lay people's implicit theories of delinquency. The different explicit psychological and sociological theories were reviewed as were studies on lay beliefs about crime and delinquency. After pilot interviews in which people were asked to list what they believed to be the major causes of delinquency, over 350 people completed a questionnaire in which they rated 30 explanations for their importance in explaining delinquency. The results showed numerous sex, age and voting differences. Conservatives tended to blame a person's poor education for his or her delinquency, while Labour voters tended to explain delinquency in terms of societal factors. A factor analysis revealed six clear explanation types for delinquency some of which were clearly related to explicit theories. Results were discussed in terms of the psychology of explanations and the relationship between explicit and implicit theories. Implications of this research were also noted.