The effects of a brief time perspective intervention for increasing physical activity among young adults

Past research has demonstrated that health behavior is correlated with time perspective: long-term thinkers are more likely than short-term thinkers to engage in health protective behaviors and less likely to engage in health damaging behaviors. To date, however, no research has experimentally demonstrated that time perspective is causally related to health behavior. We designed a brief (three 1/2-h weekly sessions) time perspective intervention to enhance long-term thinking about physical activity and examined its efficacy among two samples of young adults who signed up for fitness classes at a university recreational facility. Participants were assigned to one of three conditions: time perspective intervention, goal-setting control intervention, and no-treatment control. In Study 1, physical activity levels were assessed at preintervention, at postintervention (3 weeks later), and at 10-week follow-up (7 weeks after completion of the intervention). Controlling for preintervention physical activity levels, time perspective participants reported increased levels of physical activity relative to both other groups at postintervention, and relative to the no-treatment group at 10-week follow-up. This study provides the first experimental evidence that the effects of health behavior interventions may be enhanced by increasing participants’ long-term time perspective, and that time perspective is causally associated with health behavior. Study 2 replicated some of the effects of Study 1 using a larger sample, a six-month follow-up interval, and improved measurement of outcome. Together Studies 1 and 2 suggest that time perspective is an important ingredient in interventions designed to promote physical activity.     

A closer look at self-reported suicide attempts: false positives and false negatives

The validity of self-reported suicide attempt information is undermined by false positives (e.g., incidences without intent to die), or by unreported suicide attempts, referred to as false negatives. In a sample of 1,385 Austrian adults, we explored the occurrence of false positives and false negatives with detailed, probing questions. Removing false positives decreased the rate of suicide attempters from 4.3% to 2.7%. Probing questions also revealed 0.8% false negatives. We recommend using probing questions with both those who report a suicide attempt and those who do not report a suicide attempt to increase the validity of self-reported suicide-related information.     

Adult age differences in the perceptual span during reading

Following up on research suggesting an age-related reduction in the rightward extent of the perceptual span during reading (Rayner, Castelhano, & Yang, 2009), we compared old and young adults in an N + 2-boundary paradigm in which a nonword preview of word N + 2 or word N + 2 itself is replaced by the target word once the eyes cross an invisible boundary located after word N. The intermediate word N + 1 was always three letters long. Gaze durations on word N + 2 were significantly shorter for identical than nonword N + 2 preview both for young and for old adults, with no significant difference in this preview benefit. Young adults, however, did modulate their gaze duration on word N more strongly than old adults in response to the difficulty of the parafoveal word N + 1. Taken together, the results suggest a dissociation of preview benefit and parafoveal-on-foveal effect. Results are discussed in terms of age-related decline in resilience towards distributed processing while simultaneously preserving the ability to integrate parafoveal information into foveal processing. As such, the present results relate to proposals of regulatory compensation strategies older adults use to secure an overall reading speed very similar to that of young adults.     

Aggregate and individual replication probability within an explicit model of the research process

We study a model of the research process in which the true effect size, the replication jitter due to changes in experimental procedure, and the statistical error of effect size measurement are all normally distributed random variables. Within this model, we analyze the probability of successfully replicating an initial experimental result by obtaining either a statistically significant result in the same direction or any effect in that direction. We analyze both the probability of successfully replicating a particular experimental effect (i.e., the individual replication probability) and the average probability of successful replication across different studies within some research context (i.e., the aggregate replication probability), and we identify the conditions under which the latter can be approximated using the formulas of Killeen (2005a, 2007). We show how both of these probabilities depend on parameters of the research context that would rarely be known in practice. In addition, we show that the statistical uncertainty associated with the size of an initial observed effect would often prevent accurate estimation of the desired individual replication probability even if these research context parameters were known exactly. We conclude that accurate estimates of replication probability are generally unattainable.     

Use does not wear ragged the fabric of friendship: Thinking of objects as alive makes people less willing to replace them

Anthropomorphic beliefs about objects lead people to treat them as if they were alive. Two experiments test how anthropomorphic thought affects consumers' product replacement intentions. Consumers induced to think about their car in anthropomorphic terms (i) were less willing to replace it and (ii) gave less weight to its quality when making replacement decisions. Instead, they (iii) attended to (experimentally induced connotations of) the car's “warmth,” a feature usually considered relevant in the interpersonal domain. While anthropomorphic beliefs about brands are often seen as advantageous by marketers because they increase brand loyalty, similar beliefs about products may be less desirable.     

On the Interpretation of Response Time vs Onset Asynchrony Functions: Application to Dual-Task and Precue-Utilization Paradigms

The central bottleneck model of dual-task performance (H. Pashler and J. C. Johnston, 1998, Quarterly Journal of Experimental Psychology, 46A, 51-82) and the serial processing model of precue utilization (R. Gottsdanker, 1992, Acta Psychologica, 79, 21-43) are based on a common formal structure: They both represent response time as RT(tau)=max(X-tau, Y)+Z, where X, Y, Z denote the duration of certain processing stages specified by the models and tau denotes the onset asynchrony (SOA) between two stimuli. We consider this model within a stochastic framework in which the stage durations are random variables following an arbitrary joint distribution and derive properties of the function relating E[RT(tau)] to SOA. We present a distribution-free result which relates the slope of this function to the distribution of the random durations of the assumed processing stages. Our results allow for a direct, model-based interpretation of data from related experiments; specifically, they show how the slope of the SOA-function depends on experimental factors which selectively influence individual processing stages. We explain the implications of our results for models of dual-task performance and precue utilization and illustrate their application to data obtained by M. C. Smith (1969, Acta Psychologica, 30, 220-231) and R. Gottsdanker (1992, loc. cit.) Copyright 2001 Academic Press.     

Searching for the functional locus of the SNARC effect: Evidence for a response-related origin

Dehaene, Bossini, and Giraux (1993) showed that when participants make parity judgments, responses to numerically small numbers are made faster with the left hand, whereas responses to large numbers are made faster with the right hand (the SNARC [spatial-numerical association of response codes] effect). According to one view, the SNARC effect arises at an early processing stage due to (in)congruencies between the digit's side of presentation and its representation on the mental number line, independently of response effector(s). Alternatively, the SNARC effect might arise at a later response-related stage due to (in)congruencies between the digit's representation on the mental number line and the side of response, independently of the side of presentation. The results of three experiments, using central and lateralized stimuli, and vocal and manual responses, clearly support the view that the SNARC effect arises at a relatively late response-related stage, without substantive contributions from earlier processing stages.     

Suicidality and associated risk factors among lesbian, gay, and bisexual compared to heterosexual Austrian adults

This is the first study in German-speaking countries to compare the suicidality of lesbian, gay, and bisexual adults (n = 358) with matched heterosexual adults (n = 267). The former had significantly elevated incidences of current suicide ideation (28% vs. 13%) and lifetime suicide attempts defined in three ways (14% vs. 1% to 10% vs. 2%), including higher incidences for most suicidality-related risk factors. Increased psychosocial stress and vulnerability is indicated, especially with respect to a lack of family support. Controlling for risk factors in multivariate analysis diminished the association of sexual orientation with current suicide ideation.