Naming and categorization in young children: vocal tact training

In three experiments, 2- to 4-year-old children, following pretraining with everyday objects, were presented with arbitrary stimuli of differing shapes. In Experiment 1A, 9 subjects were trained one common tact response, "zag," to three of these and a second tact, "vek," to another three. In category match-to-sample Test 1, 4 subjects sorted accurately when required only to look at the sample before selecting from five comparisons. The remaining 5 subjects succeeded in Test 2, in which they were required to tact the sample before selecting comparisons. Experiment 1B showed, for 2 of these subjects, that tact training with 12 arbitrary stimuli established two six-member classes that were still intact 6 weeks later. In Experiment 2, 3 new subjects participated in a common tact training procedure that ensured that none of the exemplars from the same class were presented together prior to the test for three-member classes. Two subjects passed category Test 1 and the third passed Test 2. Tests showed subjects' listener behavior in response to hearing /zog/ and /vek/ to be in place. These experiments indicate that common naming is effective in establishing arbitrary stimulus classes and that category match-to-sample testing provides a robust measure of categorization.     

Neurocognitive Functioning in Posttraumatic Stress Disorder

This paper reviews the literature on performance on standard neuropsychological tests among individuals with posttraumatic stress disorder (PTSD). Of 19 studies, 16 reported impairment of attention or immediate memory (or both); however, most of these studies included PTSD patients with significant psychiatric comorbidity, so that the extent to which the observed deficits are specifically attributable to PTSD remains unclear. Other potential confounds, including medical illness, substance abuse, and motivational factors, further preclude definitive conclusions at present. Results of structural and functional neuroimaging studies of PTSD are also summarized. Two studies have reported correlations between hippocampal volume and cognitive findings in PTSD patients; functional studies have indicated specific findings in limbic regions, although the relationship of these results to neuropsychological performance remains to be explored.     

Police Officer Performance Under Stress: A Pilot Study on the Effects of Visuo-Motor Behavior Rehearsal

This study examined the effectiveness ofvisuo-motor behavior rehearsal(VMBR) as a method of reducing acute stress and improving police officer performance. Fifty-four recruits were randomly assigned to a treatment and a nontreatment condition prior to undergoing a highly stressful, critical event training scenario involving live fire. A manipulation check showed that participants who received VMBR displayed significantly lower scores on the cognitive state anxiety subscale of the Competitive State Anxiety Inventory-2; somatic state anxiety and self-confidence were unaffected by the VMBR treatment. Most importantly, participants in the VMBR training condition displayed better performance on the critical event scenario, including significantly more assailant hits. The findings are discussed with respect to the four-stage model of stress and human performance of Salas and colleagues.     

Pace of Life and Enjoyment of Life

The paper addresses the paradox that people in modern societies believe themselves to be very happy and satisfied with their lives while simultaneously are subjected to increasing time pressure and pace of life. It starts with presenting evidence for time pressure covering objective and subjective indicators. Evidence for Germany is given by comparing time-budgets in 1991/92 and in 1999. Time use among full time employed in Germany and other EU-societies in the 1990s is compared to the US and Japan by means of diary-data. As regards work life, overwork and the gap between actual and preferred working hours are examined. Survey-results on the relationship between work load, time pressure, stress and health are reported.Most of these data support the conclusion that time pressure has emerged as a major social problem. Hence citizens are beginning to consider time prosperity as a dimension of their well-being beyond their consumer wealth.However, this growing pace of life does not reduce life satisfaction and happiness. Here a paradox evolves as increasing time pressure goes hand in hand with increased subjective well-being (SWB) at country level in cross-cultural comparison as well as at individual level.In the third section some answers to this paradox are explored: A first answer is offered through the modernization theory: life satisfaction and QOL are proliferating along with economic growth and living standards. This process at the same time accelerates social life. Hence, the negative effects of time pressure are counterbalanced by various yields of the modernization process resulting in a pattern of "heavy-going" satisfaction.A second explanation is the psychological approach: time pressure fulfils positive functions for mobilizing individual resources. A variation of this argument is that the multiple-choice-society offers a wide variety of attractive options resulting in people engaging in too many activities. Here, the enjoyment of life is equated with taking advantage of every opportunity.However, this paper prefers a third approach based on Simmel's explanation of the ambivalent consequences of modernity. Even where the majority of citizens report high levels of happiness and life satisfaction – which can be explained through "arousal" or "eu-stress" – the need to ease the time-burden of disadvantaged groups and to down-speed work and social life in general is essential.     

Parenting and Family Stress Treatment Outcomes in Attention Deficit Hyperactivity Disorder (ADHD): An Empirical Analysis in the MTA Study

Parenting and family stress treatment outcomes in the MTA study were examined. Male and female (579), 7–9-year-old children with combined type Attention Deficit Hyperactivity Disorder (ADHD), were recruited at six sites around the United States and Canada, and randomly assigned to one of four groups: intensive, multi-faceted behavior therapy program alone (Beh); carefully titrated and monitored medication management strategy alone (MedMgt); a well-integrated combination of the two (Comb); or a community comparison group (CC). Treatment occurred over 14 months, and assessments were taken at baseline, 3, 9, and 14 months. Parenting behavior and family stress were assessed using parent-report and child-report inventories. Results showed that Beh alone, MedMgt alone, and Comb produced significantly greater decreases in a parent-rated measure of negative parenting, Negative/Ineffective Discipline, than did standard community treatment. The three MTA treatments did not differ significantly from each other on this domain. No differences were noted among the four groups on positive parenting or on family stress variables. Results are discussed in terms of the theoretical and empirically documented importance of negative parenting in the symptoms, comorbidities and long-term outcomes of ADHD.     

Effects of methylphenidate on sensitivity to reinforcement in children diagnosed with attention deficit hyperactivity disorder: an application of the matching law

The behavior of children diagnosed with attention deficit hyperactivity disorder (ADHD) has been hypothesized to be the result of decreased sensitivity to consequences compared to typical children. The present study examined sensitivity to reinforcement in 2 boys diagnosed with ADHD using the matching law to provide more precise and quantitative measurement of this construct. This experiment also evaluated the effects of methylphenidate (MPH) on sensitivity to reinforcement of children with ADHD. Subjects completed math problems to earn tokens under four different variable-interval (VI) schedules of reinforcement presented in random order under both medicated and nonmedicated conditions. Results showed that, in the medicated condition, the matching functions for both subjects resulted in higher asymptotic values, indicating an overall elevation of behavior rate under these conditions. The variance accounted for by the matching law was also higher under the medicated conditions, suggesting that their behavior more closely tracked the changing rates of reinforcement while taking MPH compared to placebo. Under medicated conditions, the reinforcing efficacy of response-contingent tokens decreased. Results are discussed with respect to quantifying behavioral changes and the extent to which the drug interacts with prevailing contingencies (i.e., schedule values) to influence behavioral variability.     

Preference and resistance to change with constant-duration schedule components

Previous research on preference between variable-interval terminal links in concurrent chains has most often used variable-duration terminal links ending with a single reinforcer. By contrast, most research on resistance to change in multiple schedules has used constant-duration components that include variable numbers of reinforcers in each presentation. Grace and Nevin (1997) examined both preference and resistance in variable-duration components; here, preference and resistance were examined in constant-duration components. Reinforcer rates were varied across eight conditions, and a generalized-matching-law analysis showed that initial-link preference strongly over-matched terminal-link reinforcer ratios. In multiple schedules, baseline response rates were unaffected by reinforcer rates, but resistance to intercomponent food, to extinction, and to intercomponent food plus extinction was greater in the richer component. The between-component difference in resistance to change exhibited additive effects for the three resistance tests, and was systematically related to reinforcer ratios. However, resistance was less sensitive to reinforcer ratios than was preference. Resistance to intercomponent food and to intercomponent food plus extinction was more sensitive to reinforcer ratios in the present study than in Grace and Nevin (1997). Thus, relative to variable-duration components, constant-duration components increased the sensitivity of both preference and relative resistance, supporting the proposition that these are independent and convergent measures of the effects of a history of reinforcement.     

Equivalence relations and the reinforcement contingency

Where do equivalence relations come from? One possible answer is that they arise directly from the reinforcement contingency. That is to say, a reinforcement contingency produces two types of outcome: (a) 2‐, 3‐, 4‐, 5‐, or n‐term units of analysis that are known, respectively, as operant reinforcement, simple discrimination, conditional discrimination, second‐order conditional discrimination, and so on; and (b) equivalence relations that consist of ordered pairs of all positive elements that participate in the contingency. This conception of the origin of equivalence relations leads to a number of new and verifiable ways of conceptualizing equivalence relations and, more generally, the stimulus control of operant behavior. The theory is also capable of experimental disproof.     

Money Doesn't Talk, It Swears: How Economic Stress and Resistance Resources Impact Inner-City Women's Depressive Mood

We examined the differential impact of chronic versus acute economic stress on depressive mood among a sample of 1241 low-income, single, European and African American women. Based on Hobfoll's (1988, 1989) conservation of resources (COR) theory, we predicted that acute resource loss would be more distressing than chronic economic lack. That is, although chronically impoverished conditions are stressful, the attendant resource losses created will be more distressing. We further predicted that mastery and social support would be more beneficial in offsetting the negative consequences of acute resource loss than the negative consequences of chronic economic lack, because acute loss creates identifiable demands that resources may address. Hence, we hypothesized that mastery and social support would show stress buffering effects only for material loss, not chronic lack. The findings generally supported the hypotheses, but mastery buffered only European American women's resource loss and social support buffered only African American women's resource loss. The findings are discussed in light of implications for prevention within theoretical and cultural contexts.