Five studies testing two new egoistic alternatives to the empathy-altruism hypothesis.

The empathy-altruism hypothesis claims that prosocial motivation associated with feeling empathy for a person in need is directed toward the ultimate goal of benefiting that person, not toward some subtle form of self-benefit. We explored two new egoistic alternatives to this hypothesis. The empathy-specific reward hypothesis proposes that the prosocial motivation associated with empathy is directed toward the goal of obtaining social or self-rewards (i.e., praise, honor, and pride). The empathy-specific punishment hypothesis proposes that this motivation is directed toward the goal of avoiding social or self-punishment (i.e., censure, guilt, and shame). Study 1 provided an initial test of the empathy-specific reward hypothesis. Studies 2 through 4 used three procedures to test the empathy-specific punishment hypothesis. In Study 5, a Stroop procedure was used to assess the role of reward-relevant, punishment-relevant, and victim-relevant cognitions in mediating the empathy-helping relationship. Results of these five studies did not support either the empathy-specific reward or the empathy-specific punishment hypothesis. Instead, results of each supported the empathy-altruism hypothesis. Evidence that empathic emotion evokes altruistic motivation continues to mount. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Diagnostic and confirmation strategies in trait hypothesis testing.

The role of diagnostic and confirmation strategies in trait hypothesis testing is examined. The present studies integrate theoretical and empirical work on qualitative differences among traits with the hypothesis-testing literature. Ss tested trait hypotheses from 2 hierarchically restrictive trait dimensions: introversion–extraversion and honesty–dishonesty. In Study 1, Ss generated questions to test trait hypotheses, and diagnosticity was theoretically defined (e.g., questions associated with nonrestrictive ends of trait dimensions). In Study 2, Ss selected questions from an experimenter-provided list in which diagnosticity was empirically defined. In Study 3, Ss chose between 2 equally diagnostic questions. In each of the studies, Ss showed a primary preference for diagnostic information and a secondary preference for confirmatory information. Ss' preference for diagnostic information suggests that they prefer to ask the most informative questions. The explanation for the confirmation bias is less obvious, and possible reasons for this effect are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adverse neurobiological effects of long-term use of neuroleptics: human and animal studies

Neuroleptics have revolutionized the treatment of schizophrenia and other psychoses since the early 1950s. Several adverse neurobiological effects are, however, associated with the long-term use of these agents. This article will review human and animal studies of these adverse effects, and also present some new data. Tardive dyskinesia (TD) is the most widely studied potentially persistent movement disorder resulting from long-term neuroleptic treatment, and several risk factors for TD development have been identified. Although drug-induced parkinsonism (DIP) usually disappears after the offending agent is withdrawn, a small portion of patients may have persistent parkinsonism. It is however, unclear if this is an aging-related effect. Persistent cognitive impairment associated with long-term use of typical neuroleptics has not been well documented. Atypical antipsychotics may produce improvement in cognitive performance in patients with chronic schizophrenia. MRI changes that are secondary to neuroleptics are possible, but have not yet been studied adequately. There is one unconfirmed report of neurofibrillary tangles associated with long-term neuroleptic use. A number of investigators have reported vacuous chewing movements, and neuropathologic changes following prolonged administration of neuroleptics in animals. We discuss the implications of the various reported adverse effects of long-term use of neuroleptics.     

Confirmation, disconfirmation, and information in hypothesis testing.

A number of philosophers and psychologists stress the importance of disconfirmation in reasoning and suggest that people are instead prone to a general deleterious "confirmation bias." In particular, it is suggested that people tend to test those cases that have the best chance of verifying current beliefs rather than those that have the best chance of falsifying them. We show, however, that many phenomena labeled "confirmation bias" are better understood in terms of a general positive test strategy. With this strategy, there is a tendency to test cases that are expected (or known) to have the property of interest rather than those expected (or known) to lack that property. We show that the positive test strategy can be a very good heuristic for determining the truth or falsity of a hypothesis under realistic conditions. It can, however, lead to systematic errors or inefficiencies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cytogenetic studies in reproductive loss

On the basis of the two years investigations carried on the green pea (var. Delis 11 fold), it was confirmed that blanching and freezing decrease the content of albumen and amino acids. The sterilizing belongs to the most drastic process. It was also confirmed that methionine limits the content of albumen.     

Stratified testing for treatment effects with missing data

Dawson and Lagakos (1993, Biometrics 49,1022-1032) proposed a stratified test for repeated measures data that contain missing observations. They recommended stratification based on missing data patterns and considered sufficient conditions under which the size of the test is properly retained. In this paper, we point out some practical problems with these conditions and illustrate them with their CD4 count example as well as a stimulation study. We give a less stringent condition and delineate its merit. We also discuss what to do when none of the conditions are met.     

Genetic toxicology testing requirements: official and unofficial views from Europe

This work presents genetic toxicity testing requirements in three industry sectors; pharmaceuticals, pesticides, and industrial chemicals.     

The appropriate use of null hypothesis testing.

The many criticisms of null hypothesis testing suggest when it is not useful and what it should not be used for. This article explores when and why its use is appropriate. Null hypothesis testing is insufficient when size of effect is important, but it is ideal for testing ordinal claims relating the order of conditions, which are common in psychology. Null hypothesis testing also is insufficient for determining beliefs, but it is ideal for demonstrating sufficient evidential strength to support an ordinal claim, with sufficient evidence being 1 criterion for a finding entering the corpus of legitimate findings in psychology. The line between sufficient and insufficient evidence is currently set at p     

Application of the in vitro rat hepatocyte micronucleus assay in genetic toxicology testing

The investigation of micronuclei in mitogenic stimulated hepatocytes in vitro is a quite new area of research. Nevertheless, a relatively large database comprising more than 40 tested compounds of various classes has been generated up to now. This paper reviews the available data for the in vitro rat hepatocyte micronucleus assay, showing a sensitivity of this assay in identifying mutagens and genotoxic liver carcinogens of about 85%. Additionally, all of the tested non-carcinogens gave negative results. The use of primary hepatocytes instead of permanently dividing mammalian cell lines for the investigation of micronucleus induction has several advantages. (1) The broad spectrum of metabolizing enzymes expressed in primary hepatocytes ensures an adequate activation of most xenobiotics. (2) No transfer of activated metabolites via the culture medium is necessary in this system, since the metabolizing cells are the target cells themselves. (3) Whilst in experiments with permanently dividing cells the use of S9-mix restricts the treatment period with the test compounds to 2-6 h in the hepatocyte micronucleus assay continuous treatment of up to 48 h is possible. Investigations with the pyrrolizidine alkaloids retrorsine, monocrotaline and isatidine, strong mutagens and liver carcinogens, clearly showed that at least for isatidine a prolonged exposure period is essential to detect its mutagenic potential. This compound gave positive results in rat hepatocytes but not in V79-cells/S9-mix cultures. (4) The results obtained with the hepatocyte micronucleus assay are in good agreement with the genotoxic profiles of most of the compounds tested. Only three polycyclic aromatic hydrocarbons led to 'false-negative' results, since they strongly inhibited hepatocyte proliferation and thereby prevented micronucleus formation. (5) Hepatocytes are target cells of special interest when compounds are investigated which act specifically in the liver. Especially for hepatocarcinogens classified as non-genotoxins in standard genotoxicity tests or for chemicals showing DNA-repair induction in hepatocytes but no mutagenicity in standard tests, the hepatocyte micronucleus assay can contribute to clarify the situation. (6) The rat hepatocyte micronucleus assay can be performed easily and without great efforts in parallel to the in vitro hepatocyte DNA repair test (UDS-test), using the same hepatocyte batches. (7) Similar to the two versions of the UDS-test, the hepatocyte micronucleus assay can be performed following an in vivo-in vitro protocol. In order to further validate the hepatocyte micronucleus assay, as a next step controlled interlaboratory studies should be initiated.     

Mandatory toxicology testing and chemical dependence consultation follow-up in a level-one trauma center

Comparative morphological study of 10 nominal species of pronocephalids forming a clade diagnosed by plump rounded bodies, sinuous ceca, and short esophagi supports the recognition of 7 species, with Pyelosomum longicaecum a junior synonym of P. renicapite, and P. solum and Myosaccus chelonei species incertae sedis. Phylogenetic analysis of the 7 recognized species, based on 18 morphological transformation series, produced a single tree with a consistency index of 86%. That tree suggests that Pyelosomum is paraphyletic unless Astrorchis, Epibathra, and Myosaccus are included in it. Accordingly, all are considered junior synonyms of Pyelosomum. Epibathra stenobursata is designated Pyelosomum stenobursata comb. n.     

Determining false alarm rates in null hypothesis testing research.

Supports J. Cohen's (see record 1995-12080-001) point regarding null hypothesis testing yet provides a less extreme example than the one used by Cohen. The figure offered here gives researchers a way of more accurately gauging the importance of Cohen's point for their own research, and then determining what steps would be needed to obtain acceptable false alarm rates. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cluster analysis by testing the statistical hypothesis of uniformity

This paper presents a cluster algorithm that defines the number of clusters and allows classification of data points. The basic task of the algorithm is to identify accumulations of vectors in the analysis sample of vectors. The accumulations of vectors are determined by testing the statistical hypothesis of uniformity. On the basis of accumulations, clusters are formed.     

In praise of value judgments in null hypothesis testing…and of "accepting" the null hypothesis.

Comments on the article by R. L. Hagen (see record 1997-02239-002) on null hypothesis testing. Hagen's article is constrained to the logic of deduction from an already formulated null hypothesis and the scientific conclusions that are validly drawn from one statistical decision or another. It is argued that subjective value judgment preceding the construction of the null hypothesis is an obscure precursor of the scientific logic of null hypothesis testing and that subsequent actions taken in professional practice as a result of failure to reject the null hypothesis constitutes its acceptance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A developmental study of hypothesis testing and cue selection strategies.

Previous investigators who have evaluated M. Levine's hypothesis testing model of learning have employed blank-trial probes in order to determine which hypothesis was sampled on specific trials. A method of determining which hypothesis was sampled that did not require blank trials was administered to children in Grades 1, 3, and 5, undergraduates, and old adults (mean age = 75 years). A 2-choice, multidimensional discrimination task was presented in which the Ss first chose the stimulus thought to be correct and then pointed to a single cue in a complete set of decomposed cues from the learning task. Results are in accord with other studies of hypothesis testing in that developmental differences were observed. Younger and older children differed in the cue selection strategies used during learning. Undergraduates used very efficient strategies that often led to learning, while the old adults were quite inconsistent and often failed to recognize when they had selected the correct reinforced cue. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Confirmatory bias in hypothesis testing for client-identified and counselor self-generated hypotheses.

Assessed hypothesis testing strategies exhibited by 65 counseling trainees after the trainees viewed and responded to a videotaped client–counselor interaction. Participants' hypothesis testing strategies were assessed both for a client-identified (experimenter-provided) and a counselor self-generated hypothesis about the client's problem. Results for the client-identified hypotheses failed to support either the previous finding of a strong neutral hypothesis testing strategy (e.g., D. C. Hayden, 1987; D. C. Strohmer and A. L. Chiodo, 1984) or the predicted confirmatory bias. Results for the self-generated hypotheses did reveal a strong comfirmatory tendency across 5 analog interviewing behaviors—with mean response percentages of 64% confirmatory, 21% neutral, and 15% disconfirmatory—and contradict prior research indicating that counselors do not exhibit a confirmatory bias in hypothesis testing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparisons of methods for multiple hypothesis testing in neuropsychological research.

Hypothesis testing with multiple outcomes requires adjustments to control Type I error inflation, which reduces power to detect significant differences. Maintaining the prechosen Type I error level is challenging when outcomes are correlated. This problem concerns many research areas, including neuropsychological research in which multiple, interrelated assessment measures are common. Standard p value adjustment methods include Bonferroni-, Sidak-, and resampling-class methods. In this report, the authors aimed to develop a multiple hypothesis testing strategy to maximize power while controlling Type I error. The authors conducted a sensitivity analysis, using a neuropsychological dataset, to offer a relative comparison of the methods and a simulation study to compare the robustness of the methods with respect to varying patterns and magnitudes of correlation between outcomes. The results lead them to recommend the Hochberg and Hommel methods (step-up modifications of the Bonferroni method) for mildly correlated outcomes and the step-down minP method (a resampling-based method) for highly correlated outcomes. The authors note caveats regarding the implementation of these methods using available software. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Personal hypothesis testing: The role of consistency and self-schema.

We report the results of two experiments that examined the way individuals test hypotheses about themselves. Both experiments were based on the work of Snyder (e.g., Snyder, 1981; Snyder & Skrypnek, 1981), which suggests that individuals have a confirmatory bias when testing hypotheses about others and about themselves. In Experiment 1, we examined the extent to which this bias toward confirmation persists when a negative (e.g., depression) or nonconsistent (not consistent with the individual's evaluation of him- or herself) personal hypothesis is tested. Results suggest that the negative or positive nature of a personal hypothesis does not directly influence the way individuals test their hypothesis. However, the way individuals tested personal hypotheses was influenced by hypothesis consistency. In Experiment 2, we examined the relation of a cognitive schematic variable (i.e., vulnerability for depression) and hypothesis testing. Results suggest that vulnerability is related to the way individuals test a personal hypothesis about depression. Vulnerable, low-depression participants were confirmatory when testing a depression hypothesis, whereas nonvulnerable, low-depression participants were disconfirmatory. We discuss implications for counseling and future directions for research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)