Reversal of motor learning in the vestibulo-ocular reflex in the absence of visual input

Motor learning in the vestibulo-ocular reflex (VOR) and eyeblink conditioning use similar neural circuitry, and they may use similar cellular plasticity mechanisms. Classically conditioned eyeblink responses undergo extinction after prolonged exposure to the conditioned stimulus in the absence of the unconditioned stimulus. We investigated the possibility that a process similar to extinction may reverse learned changes in the VOR. We induced a learned alteration of the VOR response in rhesus monkeys using magnifying or miniaturizing goggles, which caused head movements to be accompanied by visual image motion. After learning, head movements in the absence of visual stimulation caused a loss of the learned eye movement response. When the learned gain was low, this reversal of learning occurred only when head movements were delivered, and not when the head was held stationary in the absence of visual input, suggesting that this reversal is mediated by an active, extinction-like process.     

Psychological research online: report of Board of Scientific Affairs' Advisory Group on the Conduct of Research on the Internet

As the Internet has changed communication, commerce, and the distribution of information, so too it is changing psychological research. Psychologists can observe new or rare phenomena online and can do research on traditional psychological topics more efficiently, enabling them to expand the scale and scope of their research. Yet these opportunities entail risk both to research quality and to human subjects. Internet research is inherently no more risky than traditional observational, survey, or experimental methods. Yet the risks and safeguards against them will differ from those characterizing traditional research and will themselves change over time. This article describes some benefits and challenges of conducting psychological research via the Internet and offers recommendations to both researchers and institutional review boards for dealing with them. ((c) 2004 APA, all rights reserved)     

Effects of the periodic administration of odor or vibration on a 3-hr. vigilance task

The present study examined performance during 3 hr. of simulated sentry duty with and without the intermittent administration of low-level sensory stimuli (odor or vibration). For odor and control conditions, target-detection latency increased steadily over the course of the 3-hr. session. Administration of a tactile stimulus reduced the increase in detection latency compared to that found in odor and control conditions. For all conditions, there were no significant differences in target-detection frequency, shot accuracy, or friend-foe discrimination. Across all conditions, restlessness (motor activity) increased significantly the first hour and remained elevated for the rest of the session. Subjective measures of workload (NASA-TLX) indicated that the 3-hr. task rated high on physical demand, mental demand, frustration, and overall workload. These findings suggest that the intermittent delivery of a clearly detectable tactile stimulus can reduce reaction-time decrements that occur as time on task increases.     

Responsivity to two odorants, androstenone and amyl acetate, and the affective impact of odors on interpersonal relationships

Substantial variation exists in the importance of olfaction in influencing individuals' preferences, yet the sources of this variation remain elusive. The authors explored responsivity to 2 odorants as 1 potential source. Participants (N = 258) completed the Affective Impact of Odor Scale and were assessed for responsivity to the putative human pheromone androstenone and amyl acetate. Results showed a significant relationship between odorant responsivity and self-reports of the influence of odors. People able to smell androstenone more commonly reported odors as having a negative effect on interpersonal relationships than did people anosmic to androstenone, whereas responsivity to amyl acetate was associated with positive effects of odors on relationships. Responsivity to certain odorants may be an important factor affecting human social interactions.     

Predictive validity of the Psychopathy Checklist: Youth Version for general and violent recidivism

Several authors have expressed concern regarding the use of youth psychopathy assessments in determinations of risk for general and violent offending. The Psychopathy Checklist: Youth Version (PCL:YV) was completed with 182 male adolescent offenders in this prospective study (average 14.5 month follow-up) of general and violent recidivism. Both a two-factor and three-factor model of the PCL:YV significantly predicted general and violent recidivism at a predictive accuracy ranging from 68 to 63%. However, regression analyses indicated these associations were explained primarily by behavioral psychopathic symptoms, rather than interpersonal or affective traits. Implications for the use of psychopathy assessments for risk during adolescence are discussed.     

Associations in the course of personality disorders and Axis I disorders over time

In this study, the authors examined time-varying associations between schizotypal (STPD), borderline (BPD), avoidant (AVPD), or obsessive-compulsive (OCPD) personality disorders and co-occurring Axis I disorders in 544 adult participants from the Collaborative Longitudinal Personality Disorders Study. The authors tested predictions of specific longitudinal associations derived from a model of crosscutting psychobiological dimensions (L. J. Siever & K. L. Davis, 1991) with participants with the relevant Axis I disorders. The authors assessed participants at baseline and at 6-, 12-, and 24-month follow-up evaluations. BPD showed significant longitudinal associations with major depressive disorder and posttraumatic stress disorder. AVPD was significantly associated with anxiety disorders (specifically social phobia and obsessive-compulsive disorder). Two of the four personality disorders under examination (STPD and OCPD) showed little or no association with Axis I disorders.     

Psychosocial factors associated with adolescent boys' reports of dating violence

The prevalence of dating violence, as well as its association with psychosocial factors, was examined among a nationally representative sample of 9th- through 12th-grade U.S. boys (N = 7,434) who completed the 1999 Youth Risk Behavior Survey. The dependent variable was physical dating violence; the independent variables were violence, suicide, substance use, and sexual risk behavior. Unadjusted odds ratios (OR) and 95% confidence intervals (CI) were examined. Multivariate logistic regression was used to examine all significant independent variables from the univariate models. Adjusted OR and 95% CI were examined to assess the significance of these relationships. In terms of prevalence, 9.13% of the boys reported physical dating violence. Boys who reported sad/hopeless feelings (OR = 1.68), had attempted suicide (OR = 2.22), reported fighting (OR = 1.81), had multiple sex partners (OR = 3.53), and reported nonuse of condoms (OR = 1.66) were more likely to report physical dating violence. These findings indicate that physical dating violence among adolescent boys may be a more serious problem than has previously been recognized. It was concluded that intervention programs should include a focus on boys as not only perpetrators but also recipients of dating violence.     

Increasing false recognition rates with confirmatory feedback: a phenomenological analysis

During a simulated witness interrogation, participants were encouraged to confabulate an account consistent with false information concerning a videotaped event. The interviewer verbally affirmed some false responses. Previous research has shown that, a week later, participants often recognize confabulated events that were affirmed by the experimenter as being from the video. What is unclear is whether confirmatory feedback encouraged a change in the mental representation of the confabulated events to fit the original event or confirmation might have merely encouraged a change in beliefs about the event. To further understand the mechanisms that underlie the confirmatory feedback effect, participants were asked to judge the phenomenological experience associated with false recognition.     

Risk profiles of adolescent girls who were victims of dating violence

The prevalence of dating violence, as well as its relationship to potential risk factors, was examined among a nationally representative sample of 9th-through 12th-grade U.S. females (N = 7,824) who completed the 1999 Youth Risk Behavior Survey. The dependent variable was physical dating violence; the independent variables were violence, suicide, substance use, and sexual risk behavior. Unadjusted odds ratios (OR) and 95% confidence intervals were examined, and multivariate logistic regression analysis was conducted to identify the most significant risk factors. It was found that nearly one in ten of the adolescent girls reported dating violence. Twelfth-grade girls had the highest prevalence of dating violence. Girls who were victims of dating violence were more likely to be involved in other violent behaviors, to report extreme sadness and suicidal actions, to use illicit substances, and to engage in risky sexual behavior. Multivariate analysis revealed that dating violence was associated with sad/hopeless feelings (OR = 2.13), binge drinking (OR = 1.96), cocaine or inhalant use (OR = 2.90), multiple sex partners (OR = 2.38), nonuse of condoms (OR = 1.53), and ethnicity, specifically being Black (OR = 2.32) or Hispanic (OR = 1.82). These findings provide further evidence that there is a clustering of risk factors among certain adolescents, specifically girls who experience dating violence.     

Anxiety and selective attention in obsessive-compulsive disorder

Recently, there has been increasing evidence for information-processing deficits in individuals with obsessive-compulsive disorder (OCD). While impairments in selective attention have been identified to be central to the symptomatology of OCD, the role that situational anxiety plays in attentional processes has not been fully explored. Previous research findings were limited to tasks containing anxiety-relevant materials, only permitting for the evaluation of the impact of anxiety on simultaneous cognitive processing. Furthermore, it has not yet been determined whether the impact of anxiety is limited to selective attention or is indicative of a more general cognitive impairment. This study was designed to examine the role that situational anxiety plays in selective attention impairments. OCD participants and controls were presented with an anxiety producing statement and a neutral statement, followed by the Stroop Task. Results indicated that situational anxiety plays a significant role in the performance of tasks that require selective attention in OCD. A significant deterioration was detected in performance on selective attention tasks for the OCD participants after confronting anxiety-provoking scenarios, as compared to neutral scenarios. Anxiety did not impair performance on simple reading tasks. Possible explanations are discussed.