Stability in young infants' discrimination of optic flow

Although considerable progress has been made in understanding how adults perceive their direction of self-motion, or heading, from optic flow, little is known about how these perceptual processes develop in infants. In 3 experiments, the authors explored how well 3- to 6-month-old infants could discriminate between optic flow patterns that simulated changes in heading direction. The results suggest that (a) prior to the onset of locomotion, the majority of infants discriminate between optic flow displays that simulate only large (> 22 deg.) changes in heading, (b) there is minimal development in sensitivity between 3 and 6 months, and (c) optic flow alone is sufficient for infants to discriminate heading. These data suggest that spatial abilities associated with the dorsal visual stream undergo prolonged postnatal development and may depend on locomotor experience.     

Addiction motivation reformulated: an affective processing model of negative reinforcement

This article offers a reformulation of the negative reinforcement model of drug addiction and proposes that the escape and avoidance of negative affect is the prepotent motive for addictive drug use. The authors posit that negative affect is the motivational core of the withdrawal syndrome and argue that, through repeated cycles of drug use and withdrawal, addicted organisms learn to detect interoceptive cues of negative affect preconsciously. Thus, the motivational basis of much drug use is opaque and tends not to reflect cognitive control. When either stressors or abstinence causes negative affect to grow and enter consciousness, increasing negative affect biases information processing in ways that promote renewed drug administration. After explicating their model, the authors address previous critiques of negative reinforcement models in light of their reformulation and review predictions generated by their model.     

An Empowerment Evaluation Model for Sexual Assault Programs: Empirical Evidence of Effectiveness

Using an empowerment evaluation approach, the Sexual Assault and Rape Prevention (SARP) Evaluation Project brought together university researchers, public health evaluators, state funders, and program staff to provide evaluation training and consultation to all state-funded rape prevention and victim services programs in Michigan. In this paper, the specific activities of the SARP project are described, and process and outcome data are presented that address the effectiveness of this empowerment evaluation approach. Based on subjective reports from program staff and objective data obtained from state funders, results suggest that this evaluation model was successful in helping 90% of the prevention programs and 75% of the victim services programs successfully develop and launch program evaluations. One-year follow-up data indicate that 90% of the programs had sustained their evaluation efforts after the formal work of the SARP project had ended.     

Unifying representations and responses: perseverative biases arise from a single behavioral system

Abstract— A dominant account of perseverative errors in early development contends that such errors reflect a failure to inhibit a prepotent response. This study investigated whether perseveration might also arise from a failure to inhibit a prepotent representation. Children watched as a toy was hidden at an A location, waited during a delay, and then watched the experimenter find the toy. After six observation-only A trials, the toy was hidden at a B location, and children were allowed to search for the toy. Two- and 4-year-olds' responses on the B trials were significantly biased toward A even though they had never overtly responded to this location. Thus, perseverative biases in early development can arise as a result of prepotent representations, demonstrating that the prepotent-response account is incomplete. We discuss three alternative interpretations of these results, including the possibility that representational and response-based biases reflect the operation of a single, integrated behavioral system.     

Emotional correlates of the different dimensions of schizotypal personality disorder

Two studies explored which different dimensions of schizotypal personality disorder (SPD) were associated with negative affect, attention to emotions, clarity of emotions, and emotional intensity/instability. Study 1 included 247 college students, and questionnaires were used to measure SPD. Study 2 included 225 community residents, oversampling for individuals with elevated levels of SPD, and semistructured diagnostic interviews were used to measure SPD. In both studies (a) higher levels of negative affect were associated with higher levels of both cognitive-perceptual and interpersonal symptoms, (b) cognitive-perceptual disturbances were associated with greater attention to emotion, whereas interpersonal disturbances were associated with less attention to emotion, and (c) lower levels of emotional clarity were associated with higher levels of suspiciousness.     

Scaling a motor skill through observation and practice

The authors examined the proposal that a motor skill is scaled through physical practice and not through observation of a model. In 4 groups, participants (N = 32) did or did not imitate a model bowling a ball to a target 8 m away. In an assessment phase, those groups did or did not observe the same model bowling a ball to a target 4 m away. Participants who viewed a model in the assessment phase were more accurate and consistent in terms of bowling accuracy than were those who did not. Their shoulder and wrist velocity profiles were more similar to those of the 4-m model than were those of the no-model group. Participants who had previous practice and viewed a demonstration were more accurate at scaling the wrist of the bowling arm. Observing a demonstration facilitates the acquisition of control-related features of a movement. Furthermore, early acquisition of coordination aids the use of velocity information for scaling the endpoint of the primary effector.     

Family secrecy: a comparative study of juvenile sex offenders and youth with conduct disorders

The reported research was designed to compare adjudicated male juvenile sexual offenders and youth with conduct disorders on five aspects of family secrecy and deception. Twenty-nine male juvenile sex offenders and 32 comparison youth from three child welfare agencies in New York State participated in the study. Research assistants, blind to the hypotheses of the study and status of the youth, coded agency records for five variables identified a priori as a basis of comparison. Analyses revealed that the two groups were different on three of the five and on the total number of items scored. Families of juvenile sex offenders told more lies, had more family myths, and were more likely to be involved in taboo behavior. Logistic regression revealed that this factor of family deception significantly increased the odds of sexual offending over and above other measures of family pathology. These data support the hypotheses of the study and have implications for both clinical practice and future research in this area.     

Smoking withdrawal dynamics: I. Abstinence distress in lapsers and abstainers

Smoking withdrawal reports from a clinical trial (n = 893) were submitted to hierarchical linear modeling as a cross-method replication of a heterogeneity approach to withdrawal measurement and to clarify the influence of postcessation smoking on symptom reports. Five individual difference parameters tapping distinct facets of withdrawal were derived: intercepts (mean severity), linear slope (direction and rate of change), quadratic trend (curvature), volatility (scatter) and, among lapsers, a cigarette coefficent (smoking-related deflections of symptoms). All parameters were highly variable across persons. Lapsers had more aversive symptom patterns than abstainers, and symptoms tended to be higherthan otherwise predicted on lapse days. These results reinforce the conclusion that withdrawal symptoms are highly variable and argue against discarding withdrawal data from participants who lapse.