Laboratory behavioral measures of impulsivity

Previous research and theory have conceptualized impulsivity as a multifaceted construct that requires multiple modes of measurement for accurate assessment. This article describes a software package that includes four paradigms for measuring multiple and unique aspects of impulsivity. Specifically, four tasks are described: (1) the two choice impulsivity paradigm, (2) the single key impulsivity paradigm, (3) the GoStop impulsivity paradigm, and (4) the time paradigm. These tasks measure processes related to the capacity to tolerate delay for reward, to inhibit an already initiated response, and to estimate the passage of time. These processes have been found to be important to the understanding of impulsive behaviors. The programs are flexible and allow the experimenter to manipulate a number of parameters related to delay-reward contingencies, timing, performance feedback/payment, and data output variables. Manipulation of these parameters makes the paradigms scalable to a wide range of ability levels and appropriate for samples ranging from children to adults. The four paradigms in this software package are available at no cost and can be obtained by contacting the corresponding author.     

Who's in Charge?: Coparenting in South and Southeast Asian Families

In light of the evolving roles of parents and the involvement of extended family within Asian cultures, the traditionally Western dyadic coparenting construct must be reconceptualized to include not only the coparenting relationship, but also other caregivers within the coparenting network. Theoretical and empirical evidence on coparental systems are discussed and two studies from South and Southeast Asian cultures are presented to highlight subcultural variations in cocaregiving networks. Results indicated that mothers were the primary caregivers across both cultural contexts. Extended family members assumed important coparental responsibilities in both cultural contexts. These findings highlight the need to reconceptualize and expand the dyadic coparental unit to include extended family members. We also discuss the relevance of the broader coparental network in examining the Asian childs education as well as cognitive and socioemotional development.     

Laboratory measured behavioral impulsivity relates to suicide attempt history

The purpose of this study was to examine the relationship between laboratory behavioral measured impulsivity (using the Immediate and Delayed Memory Tasks) and suicidal attempt histories. Three groups of adults were recruited, those with either: no previous suicide attempts (Control, n = 20), only a single suicide attempt (Single, n = 20), or multiple suicidal attempts (Multiple, n = 10). As hypothesized, impulsive responses increased with the number of suicide attempts (Control < Single < Multiple). This study helps to demonstrate how laboratory behavioral measures of impulsivity can be used to discriminate groups based on suicidal histories among samples not currently exhibiting significant suicidal behaviors.     

Contraction bias in memorial quantifying judgment: does it come from a stable compressed memory representation or a dynamic adaptation process?

A common response bias in psychophysical judgments is regression toward the mean (overestimation of small and underestimation of large values, or the response contraction bias). The same bias is observed in magnitude estimation from memorized quantities. Participants estimated alphabetic interval distances between 2 letters for different levels of interletter distances. The underestimated and overestimated values and the point of least error changed, depending on the level of alphabetic distances judged; furthermore, their estimation showed a progressively increasing tendency toward the mean, rendering the estimation progressively less accurate as the estimation task was repeated. We conclude that the regression toward the mean in memorial quantifying judgment derives from a cognitive adaptation process rather than from a permanent, compressed memory representation of the stimuli. Two opposing views on the adaptive meaning of this judgment bias are discussed.     

VIZ: The visualization assessment and training Web site

The VIZ Website(http:/viz.bd.psu.ech]/viz/) was developed as a free and open portal for assessment and training of spatial skills. Using Macromedia Authorware, it allows the collection of response times and accuracies from four spatial tasks: mental rotation, paper folding, water level judgments, and spatial working memory. Additional tasks are under development. The site has been used for a variety of teaching and research purposes. For example, incoming engineering students have completed the tasks to assess their spatial skills before beginning their graphics courses. Those with poorer skills can then receive the appropriate remedial instruction. The VIZ site has also been used to teach about spatial cognition and to do research outside the laboratory setting. Finally, we are using the site to conduct basic research on spatial cognition, including an examination of the factors that may reduce gender differences in performance.     

Conceptual processing effects on automatic memory

In the present study, influences of conceptual processing on automatic forms of memory were investigated, using a category production task. The experiment employed Jacoby's (1991) process dissociation procedure and fits of multinomial models to estimate conscious and automatic memory for semantic and graphemic study tasks. Memory estimates from a generate-source model indicated more automatic memory for semantic than for graphemic items on the category production task. These results provide support for conceptual processing influences on automatic forms of memory.     

Viewpoint alignment and response conflict during spatial judgment

Spatial judgment (e.g., identifying the relative location, such as left or right, of a target) from a reference point becomes more difficult with increasing disparity between the relevant allocentric viewpoint and the observer-centered viewpoint. The viewpoint alignment hypothesis suggests that this misalignment effect is due to a realignment process that reconciles two viewpoints, implying that providing an advance cue for a viewpoint should facilitate the subsequent judgment. We examined whether advance viewpoint information can reduce the misalignment effect and whether the misalignment effect reflects response conflict, as well as realignment of viewpoints. In Experiment 1, the misalignment effect decreased with advance viewpoint information, suggesting that the misalignment effect indeed reflects viewpoint realignment. In Experiment 2, the misalignment effect was greater with spatial response codes that might conflict with the spatially arranged response keys than with arbitrary responses with no such conflict. These results suggest that the misalignment effect may arise from both viewpoint realignment and response conflicts.     

Commission error rates on a continuous performance test are related to deficits measured by the Benton Visual Retention Test

This study is one in a series investigating the relationship between impulsive behavior on a Continuous Performance Test (i.e., the Immediate and Delayed Memory Task) and other cognitive deficits measured by clinical instruments. Forty-two adolescents were selected for two groups, controls and hospitalized patients with disruptive behavior disorders. Each adolescent completed the Immediate and Delayed Memory Task and the Benton Visual Retention Test. Our main findings were that, even when controlling for IQ, the Immediate and Delayed Memory Task commission errors were associated with adverse Benton performance, but only in the patient group. These results may be explained by a shared association between processes of impulsivity and other deficits of executive control that may interfere with successful performance of the Benton.     

The category test perseveration, loss of set, and memory scales: three new scales and their relationship to executive functioning measures

The Category Test (CT) is a neuropsychological measure that taps into multiple domains of complex reasoning but yields a single error score, limiting the use of the test. In this study, three new CT scales were developed to assess specific aspects of executive dysfunction: Perseveration, Failure to Maintain Cognitive Set, and Inability to Recall and Re-Initiate Past Behavior. The relationship of these scales to well-established neuropsychological measures was examined in head-injured individuals and schizophrenia patients. The CT Perseveration score was correlated with the Wisconsin Card Sorting Test (WCST) Perseverative Responses score, but also with measures from the Wechsler Memory Scale-Revised and the California Verbal Learning Test. The CT Memory score correlated with other memory measures, but also with the WCST Perseveration measure. Although future studies designed to test discriminant and convergent validity are warranted, these scales may be useful in determining specific aspects of impaired CT performance.     

Contemporary longitudinal methods for the study of trauma and posttraumatic stress disorder

Traditional methods for analyzing trends in longitudinal data have typically emphasized average group change over time. In this article, we propose multilevel, regression-based methods for examining inter-individual differences in intra-individual change and apply these methods to research in trauma and posttraumatic stress disorder (PTSD). The outcome or dependent variable of interest is reconceptualized as an index of dynamic change reflecting the trend or trajectory of an individual's PTSD symptom severity scores across time. A basic statistical model is presented, and analyses and findings are demonstrated with an existing database used in previously published studies. The methods offer promise for future study of the natural course of PTSD chronicity or recovery, risk and resilience factors that influence individual growth or decline, and critical timepoints for intervention.