Synchronous change and perception of object unity: evidence from adults and infants.

Adults and infants display a robust ability to perceive the unity of a center-occluded object when the visible ends of the object undergo common motion (e.g. Kellman, P.J., Spelke, E.S., 1983. Perception of partly occluded objects in infancy. Cognitive Psychology 15, 483-524). Ecologically oriented accounts of this ability focus on the primary of motion in the perception of segregated objects, but Gestalt theory suggests a broader possibility: observers may perceive object unity by detecting patterns of synchronous change, of which common motion is a special case. We investigated this possibility with observations of adults and 4-month-old infants. Participants viewed a center-occluded object whose visible surfaces were either misaligned or aligned, stationary or moving, and unchanging or synchronously changing in color or brightness in various temporal patterns (e.g. flashing). Both alignment and common motion contributed to adults' perception of object unity, but synchronous color changes did not. For infants, motion was an important determinant of object unity, but other synchronous changes and edge alignment were not. When a stationary object with aligned edges underwent synchronous changes in color or brightness, infants showed high levels of attention to the object, but their perception of its unity appeared to be indeterminate. An inherent preference for fast over slow flash rates, and a novelty preference elicited by a change in rate, both indicated that infants detected the synchronous changes, although they failed to use them as information for object unity. These findings favor ecologically oriented accounts of object perception in which surface motion plays a privileged role.     

Control' of reflexive and voluntary saccades in the gap effect.

In two experiments, we examined whether voluntary and reflexive saccades shared a common fixation disengagement mechanism. Participants were required to perform a variety of tasks, each requiring a different level of information processing of the display prior to execution of the saccade. In Experiment 1, participants executed either a prosaccade or an antisaccade upon detecting a stimulus array. In Experiment 2, participants executed a prosaccade to a stimulus array only if the array contained a target item. The target could be a line (easy search) or a digit (difficult search). The critical manipulation in both experiments was the relative timing between the removal of the fixation stimulus and the onset of the stimulus array. In both experiments, it was found that saccadic latencies were shortest when the fixation stimulus was removed before the onset of the stimulus array--a gap effect. It was concluded that reflexive and voluntary saccades share a common fixation disengagement mechanism that is largely independent of higher level cognitive processes.     

Testimony based on the Millon Clinical Multiaxial Inventory: review, commentary, and guidelines

Test results from the MCMI have been ruled admissible in court for a variety of clinical and forensic issues. This article addresses MCMI issues such as the test's applicability and admissibility of test results in forensic evaluations, test administration, test scoring, malingering and deception, prediction and diagnosis of behavior, reliability, validity, operating characteristics and diagnostic efficiency statistics, and use of computer-assisted interpretation of test results for forensic presentation. Recommendations are suggested for dealing with each of these issues in a forensic context.     

Course of Treatment During a Cohort-Based Inpatient Program for Posttraumatic Stress Disorder

This study examined one group of veterans with post-traumatic stress disorder (PTSD) over the course of a four month inpatient treatment program. The aim of the study was to examine treatment process factors that may contribute to the generally poor outcome reported in previous studies. Group members made weekly ratings in the domains of PTSD symptoms, morale, interpersonal relationships, and physical problems. Results contrasted with clinical assumptions usually made regarding the treatment process in these programs. Despite an appearance of cohesion among group members, variation of scores on functional domains was explained largely by individual differences. Progress through the program showed a strongly linear pattern, with no phase effects. Somatic complaints did not increase during the phase when traumatic material was explored. Degree of improvement or worsening was best predicted by level of PTSD symptoms at admission, indicating that more symptomatic veterans did worse in the program. Additional factors of race, combat exposure, childhood abuse, and application for disability had no effect on the process variables measured.     

Family and Contextual Predictors of Depressive Symptoms in Inner-City African American Youth

Family and contextual predictors of depression in inner-city, African American youth have rarely been examined. In this study we explore the contribution of current and historical life events, family conflict, perceived social support from mother, maternal depression, and maternal explanatory style to the depressive symptoms of inner-city African American school-age (M = 10.7 years) children. Home interviews were conducted with 89 mother and child dyads living in moderate- to high-violent areas of a southeastern city. Regression analyses revealed that the children in this sample with higher levels of depressive symptoms had higher levels of child-reported everyday stress, were more likely to have been abused at some point in their past, came from homes with mothers who were less well educated, and had mothers who reported higher levels of depression, a past history of domestic abuse, as well as a less pessimistic explanatory style. Implications for interventions with inner-city African American families are discussed.     

Familiarity and pronounceability of nouns and names

Ratings of familiarity and pronounceability were obtained from a random sample of 199 surnames (selected from over 80,000 entries in the Purdue University phone book) and 199 nouns (from the Ku?era-Francis, 1967, word database). The distributions of ratings for nouns versus names are substantially different: Nouns were rated as more familiar and easier to pronounce than surnames. Frequency and familiarity were more closely related in the proper name pool than the word pool, although both correlations were modest. Ratings of familiarity and pronounceability were highly related for both groups. A production experiment showed that rated pronounceability was highly related to the time taken to produce a name. These data confirm the common belief that there are differences in the statistical and distributional properties of words as compared to proper names. The value of using frequency and the ratings of familiarity and pronounceability for predicting variations in actual pronunciations of words and names are discussed.     

Control of reflexive and voluntary saccades in the gap effect

In two experiments, we examined whether voluntary and reflexive saccades shared a common fixation disengagement mechanism, Participants were required to perform a variety of tasks, each requiring a different level of information processing of the display prior to execution of the saccade. In Experiment 1, participants executed either a prosaccade or an antisaccade upon detecting a stimulus array. In Experiment 2, participants executed a prosaccade to a stimulus array only if the array contained a target item. The target could be a line (easy search) or a digit (difficult search). The critical manipulation in both experiments was the relative timing between the removal of the fixation stimulus and the onset of the stimulus array. In both experiments, it was found that saccadic latencies were shortest when the fixation stimulus was removed before the onset of the stimulus array—a gap effect. It was concluded that reflexive and voluntary saccades share a common fixation disengagement mechanism that is largely independent of higher level cognitive processes.     

Three perspectives on addiction

Three perspectives on addiction promulgated during the 1990s are reviewed, along with many earlier contributions to the understanding of addictive illness. It is suggested that these distinct yet overlapping formulations of the dynamics of addiction form a hierarchy for each patient suffering from an addiction. Assessment of a patient's ego strength, and of the relative importance of addictive behaviors in overall character structure, allows referral to various types of treatment, including psychoanalytic therapy. Case examples are presented, including material from the psychoanalysis of a woman addicted to heroin, methadone, cocaine, amphetamines, nicotine, alcohol, and shopping.     

Adolescent substance use disorders: findings from a 14-year follow-up of speech/language-impaired and control children.

Intervening on the development of adolescent addiction requires an understanding of the role of precursors. In a community sample of youth with and without early childhood speech/language (S/L) impairments, 12.7% of participants had a substance use disorder (SUD). Among these participants, 42.0% met criteria for more than 1 SUD. Interestingly, rates of SUDs did not differ by S/L status. However, S/L-impaired participants did show greater psychiatric comorbidity and poorer functioning. A total of 80% of S/L participants with SUDs had a concurrent diagnosis of antisocial personality disorder, compared with 43.8% of SUDs controls. In a logistic regression analysis, we found age 5 mother-rated problem behavior scores and an interaction between S/L status and teacher-rated conduct problem scores were predictive of SUDs. High conduct scores were predictive of SUDs development among control participants but not among S/L-impaired participants. First substance use and initial SUDs symptoms suggest that a window of opportunity exists to reach these troubled young people before they spiral into addiction.     

The importance of semantic similarity to the irrelevant speech effect

Irrelevant speech disrupts immediate recall of a short sequence of items. Salamé and Baddeley (1982) found a very small and nonsignificant increase in the irrelevant speech effect when the speech comprised items semantically identical to the to-be-remembered items, leading subsequent researchers to conclude that semantic similarity plays no role in the irrelevant speech effect. Experiment 1 showed that strong free associates of the to-be-remembered items disrupted serial recall to a greater extent than words that were dissimilar to the to-be-remembered items. Experiment 2 showed that this same pattern of disruption in a free recall task. Theoretical implications of these findings are discussed.