Hail the impossible: p-values, evidence, and likelihood

Significance testing based on p-values is standard in psychological research and teaching. Typically, research articles and textbooks present and use p as a measure of statistical evidence against the null hypothesis (the Fisherian interpretation), although using concepts and tools based on a completely different usage of p as a tool for controlling long-term decision errors (the Neyman-Pearson interpretation). There are four major problems with using p as a measure of evidence and these problems are often overlooked in the domain of psychology. First, p is uniformly distributed under the null hypothesis and can therefore never indicate evidence for the null. Second, p is conditioned solely on the null hypothesis and is therefore unsuited to quantify evidence, because evidence is always relative in the sense of being evidence for or against a hypothesis relative to another hypothesis. Third, p designates probability of obtaining evidence (given the null), rather than strength of evidence. Fourth, p depends on unobserved data and subjective intentions and therefore implies, given the evidential interpretation, that the evidential strength of observed data depends on things that did not happen and subjective intentions. In sum, using p in the Fisherian sense as a measure of statistical evidence is deeply problematic, both statistically and conceptually, while the Neyman-Pearson interpretation is not about evidence at all. In contrast, the likelihood ratio escapes the above problems and is recommended as a tool for psychologists to represent the statistical evidence conveyed by obtained data relative to two hypotheses.     

Controlling anger in self-reported sober and alcohol intoxicated states: moderating effects of trait anger and alcohol consumption

Controlling anger in self-reported sober and alcohol intoxicated states: Moderating effects of trait anger and alcohol consumption. Scandinavian Journal of Psychology 52, 382-388. Retrospective self-reports about prior sober and alcohol intoxicated states were explored to reveal moderating effects of trait anger and alcohol consumption on anger control. The analyses were based on self-reports of trait anger and alcohol consumption as well as self-reports of the participants' typical levels of anger control in sober and alcohol intoxicated states in a population based sample of Finnish twins and their siblings (N = 4,852). The reported levels of anger control were lower regarding prior alcohol intoxicated states than sober states. A three-way interaction between alcohol consumption, trait anger and anger control was found. Whereas no interaction between alcohol consumption and trait anger was found in the self-reported sober state, there was an interactive effect of trait anger and alcohol consumption on anger control in the intoxicated state, indicating that the difference in anger control between those with high levels of alcohol consumption and those with low levels, was greater at higher levels of trait anger. Women had lower levels of anger control than men, but the relationship between trait anger, alcohol consumption and anger control was similar for both genders. In conclusion, the results showed that those with high levels of trait anger and alcohol consumption showed the lowest levels of anger control in self-reported alcohol intoxicated states, and indicate the importance of separating between anger control when sober and intoxicated since anger control seems to be differently related to at least trait anger and alcohol consumption in these states.     

Oh, it's you again: memory interference from irrelevant emotional and neutral faces

In two experiments, repeated runs of a continuous recognition task were employed to assess healthy participants' ability to handle interference from irrelevant emotional and neutral memories. Presumably, such interference can be due to salience from either emotional or mnemonic processing. In both experiments, participants made more false alarms to emotional faces that were familiar from preceding runs (i.e., emotion-induced temporal-context confusion). Participants performed well for neutral faces in the first experiment including only two runs. However, increasing the number of runs to four in the second experiment induced temporal context confusion also for neutral faces. The findings suggest that memory interference can be induced when the salience of irrelevant information is erroneously considered diagnostic for memory judgements.     

Parfit on fission

Derek Parfit famously defends a number of surprising views about “fission.” One is that, in such a scenario, it is indeterminate whether I have survived or not. Another is that the fission case shows that it does not matter, in itself, whether I survive or not. Most critics of the first view contend that fission makes me cease to exist. Most opponents of the second view contend that fission does not preserve everything that matters in ordinary survival. In this paper I shall provide a critique that does not rely on either of these contentions. There are other, interrelated reasons to reject Parfit’s defense of the two theses. In particular, the availability of the following view creates trouble for Parfit: I determinately survive fission, but it is indeterminate which fission product I am.     

Prolonged institutional rearing is associated with atypically large amygdala volume and difficulties in emotion regulation

Early adversity, for example poor caregiving, can have profound effects on emotional development. Orphanage rearing, even in the best circumstances, lies outside of the bounds of a species-typical caregiving environment. The long-term effects of this early adversity on the neurobiological development associated with socio-emotional behaviors are not well understood. Seventy-eight children, who include those who have experienced orphanage care and a comparison group, were assessed. Magnetic resonance imaging (MRI) was used to measure volumes of whole brain and limbic structures (e.g. amygdala, hippocampus). Emotion regulation was assessed with an emotional go-nogo paradigm, and anxiety and internalizing behaviors were assessed using the Screen for Child Anxiety Related Emotional Disorders, the Child Behavior Checklist, and a structured clinical interview. Late adoption was associated with larger corrected amygdala volumes, poorer emotion regulation, and increased anxiety. Although more than 50% of the children who experienced orphanage rearing met criteria for a psychiatric disorder, with a third having an anxiety disorder, the group differences observed in amygdala volume were not driven by the presence of an anxiety disorder. The findings are consistent with previous reports describing negative effects of prolonged orphanage care on emotional behavior and with animal models that show long-term changes in the amygdala and emotional behavior following early postnatal stress. These changes in limbic circuitry may underlie residual emotional and social problems experienced by children who have been internationally adopted.     

Three modes of psychotherapy and their requisite core skills

The field of psychotherapy suffers from the lack of an integrative meta‐perspective on the large variety of existing psychotherapies and on the therapeutic skills involved. In the present paper, it is suggested that the development of a more comprehensive view of this field may be facilitated if we differentiate between three modes of psychotherapy, which require different therapeutic core skills: (a) an educational mode, which requires teaching skills; (b) a reparative mode, which requires analytic‐conceptualising skills to identify some kind of disordered functioning, in combination with specific relational‐technical skills to repair this dysfunction; and (c) a developmental mode, which involves engaging in a therapeutic relationship with patients to facilitate their personal growth, and which requires non‐directivity skills. In addition, some therapeutic skills (e.g., awareness and communication skills) may be more or less important in all modes of treatment. Concrete manifestations of the three different modes of psychotherapy are discussed in terms of five different theoretical perspectives on psychotherapy: the common factors, the humanistic‐experiential mindfulness cognitive‐behavioural (CBT) and psychodynamic perspective. The common factors model is criticised as being insufficient in several respects. Finally, it is argued that if personal therapeutic skills are essential to the effects of psychotherapy, then empirical research on psychotherapy needs to be re‐oriented towards a person‐oriented study of therapist skills in action, in the context of a study of the interaction between therapist and patient.     

Formalizing common sense: an operator-based approach to the Tibbles–Tib problem

The paper argues, that a direct formalization of the way common sense thinks about the numerical identity of enduring entities, requires that traditional predicate logic is developed. If everyday language mirrors the world, then persons, organisms, organs, cells, and ordinary material things can lose some parts but nonetheless remain numerically exactly the same entity. In order to formalize this view, two new logical operators are introduced; and they bring with them some non-standard syntax. One of the operators is called ‘the instantiation operator’; it is needed because the existential quantifier and its traditional relatives cannot do the job required. The other operator is called ‘the form-on-matter operator’, and it allows an individual (an instance of a form) to stay the same even though some of its parts (its constituting matter) is taken away from it. Also, a certain kind of predicates, called ‘nature terms’, is needed in order to represent what gives a particular its kind of identity. Both the operators and the nature terms introduced can be used in constructions of formal languages and formal systems, but no such constructions are made in the paper. The paper is structured as a comment on the philosophical problem called ‘the problem of the cats Tibbles and Tib’.     

Genetic effects on male sexual coercion

The genetic and environmental influences on sexual coercion, and to what extent its associations with alcohol use and psychopathy depend on shared genetic and environmental effects, were explored in a Finnish population-based sample of 938 men, aged 33-43 years, using the classical twin study design. All three phenotypes were associated positively and affected by genes (sexual coercion 28%, alcohol use 60%, psychopathy 54%), with 46% of the correlation between sexual coercion and psychopathy, 89% of the correlation between alcohol use and psychopathy and 100% of the correlation between sexual coercion and alcohol use being explained by shared genetic effects. Further, the results showed that a proportion of the variance in sexual coercion was derived from a highly genetic source that was common with alcohol use and psychopathy. This latent factor was hypothesized to reflect a general tendency for antisocial behavior that is pervasive across different situations. Relevant theories on sexual coercion were discussed in light of the results.     

Effects of social isolation and environmental enrichment on atherosclerosis in ApoE-/- mice

Social support and a stimulating environment have been suggested to reduce stress reactions and cardiovascular risk. The aim of this study was to assess the role of environmental enrichment and social interaction for development of atherosclerosis in atherosclerosis prone mice. Male ApoE-/- mice were divided into four groups and followed during 20 weeks: (i) enriched environment (E, n=12), (ii) deprived environment (ED, n=12), (iii) enriched environment with exercise (E-Ex, n=12) and (iv) socially deprived by individual housing (SD, n=10). Plasma lipid and cytokine concentrations were measured. Atherosclerosis was quantified in cross-sections of innominate artery and en face in thoracic aorta. Plaque area was significantly increased in SD mice in the innominate artery (P<0.05 vs. all other groups), but not in the thoracic aorta. Plasma lipids were increased in SD mice (P<0.001 vs. all for total cholesterol, P<0.05 vs. E and P<0.01 vs. ED for triglycerides). Plasma concentration of granulocyte-colony stimulating factor (G-CSF) was decreased in SD mice compared to E mice (P<0.05). Thus, social isolation increased atherosclerosis and plasma lipids in ApoE-/- mice. Reduction in plasma G-CSF levels may hamper endothelial regeneration in the atherosclerotic process. While environmental enrichment did not affect atherosclerosis, social isolation accelerated atherosclerosis.     

Turning failures into successes: a methodological shortcoming in empirical research on surrogate accuracy

Decision making for incompetent patients is a much-discussed topic in bioethics. According to one influential decision making standard, the substituted judgment standard, a surrogate decision maker ought to make the decision that the incompetent patient would have made, had he or she been competent. Empirical research has been conducted in order to find out whether surrogate decision makers are sufficiently good at doing their job, as this is defined by the substituted judgment standard. This research investigates to what extent surrogates are able to predict what the patient would have preferred in the relevant circumstances. In this paper we address a methodological shortcoming evident in a significant number of studies. The mistake consists in categorizing responses that only express uncertainty as predictions that the patient would be positive to treatment, on the grounds that the clinical default is to provide treatment unless it is refused. We argue that this practice is based on confusion and that it risks damaging the research on surrogate accuracy.