The psychological neuroscience of depression: implications for understanding effects of deep brain stimulation

In this article it is suggested that current psychological theories of depression presuppose that this condition will develop as a result of a vicious circle involving negatively biased communication between systems of emotional stress-/alarm-signaling, executive functions and mood regulation. These systems may from a neuroanatomical point of view be located in the limbic system, the orbitofrontal and lateral prefrontal cortex and the hypothalamus-pituitary-adrenal (HPA-) axis respectively. The theoretical and practical implications of this model for the understanding of pharmacological treatments of depression are briefly discussed and this theory is related to the catecholamine hypothesis of depression. The model is furthermore discussed in relation to deep brain stimulation (DBS) of treatment resistant major depression. Similarities and differences between this perspective and the one advocated by the "homeostatic theory" of depression are discussed. It is concluded that a topographical psychological theory may offer a useful heuristic in thinking about depression and that it offers several testable predictions about treatments of the disorder.     

Data and phenomena in conceptual modelling

The distinction between data and phenomena introduced by Bogen and Woodward (Philosophical Review 97(3):303–352, 1988) was meant to help accounting for scientific practice, especially in relation with scientific theory testing. Their article and the subsequent discussion is primarily viewed as internal to philosophy of science. We shall argue that the data/phenomena distinction can be used much more broadly in modelling processes in philosophy.     

Desensitization to media violence: links with habitual media violence exposure, aggressive cognitions, and aggressive behavior

This study examined the links between desensitization to violent media stimuli and habitual media violence exposure as a predictor and aggressive cognitions and behavior as outcome variables. Two weeks after completing measures of habitual media violence exposure, trait aggression, trait arousability, and normative beliefs about aggression, undergraduates (N = 303) saw a violent film clip and a sad or a funny comparison clip. Skin conductance level (SCL) was measured continuously, and ratings of anxious and pleasant arousal were obtained after each clip. Following the clips, participants completed a lexical decision task to measure accessibility of aggressive cognitions and a competitive reaction time task to measure aggressive behavior. Habitual media violence exposure correlated negatively with SCL during violent clips and positively with pleasant arousal, response times for aggressive words, and trait aggression, but it was unrelated to anxious arousal and aggressive responding during the reaction time task. In path analyses controlling for trait aggression, normative beliefs, and trait arousability, habitual media violence exposure predicted faster accessibility of aggressive cognitions, partly mediated by higher pleasant arousal. Unprovoked aggression during the reaction time task was predicted by lower anxious arousal. Neither habitual media violence usage nor anxious or pleasant arousal predicted provoked aggression during the laboratory task, and SCL was unrelated to aggressive cognitions and behavior. No relations were found between habitual media violence viewing and arousal in response to the sad and funny film clips, and arousal in response to the sad and funny clips did not predict aggressive cognitions or aggressive behavior on the laboratory task. This suggests that the observed desensitization effects are specific to violent content.     

Violent, nonviolent, and substance-related offending over the life course in a cohort of males and females treated for substance misuse as youths

Most studies on adolescent offending heterogeneity are based on general population samples, and few include individuals with substance misuse or look specifically at substance-related offending. It is also unclear how offender subtypes develop after young adulthood or how offending heterogeneity varies between genders. This study aimed to identify subgroups of offending among adolescents with misuse problems and to examine associations with offending in adulthood. The study included 1,992 females and males that consulted a clinic for adolescents with misuse problems between 1968 and 1971. Latent Class Analyses were conducted to identify subgroups based on violent and nonviolent offending before age 20. Participants were then followed until age 50 and reexamined regarding violent, nonviolent, and substance-related crimes. Associations between subgroups before age 20 and subgroups age 21-50 were examined. Before age 20, three subgroups were identified among the females and six among the males. Males were more specialized in their offending and demonstrated higher levels of offending. Results pointed to both stability and decrease of violent and nonviolent offending, and to the emergence of substance-related offending in adulthood in both genders. The connection between substance-related crimes and general delinquency in adulthood among individuals treated for substance misuse suggests that interventions should also address substance misuse for reducing the overall volume of crime. This study also highlights the importance of including females in research on offending heterogeneity.     

A randomized controlled trial of mother–infant psychoanalytic treatment: I. Outcomes on self‐report questionnaires and external ratings

Mother–infant relationship disturbances occur in three domains: maternal distress, infant functional problems, and relationship difficulties. They constitute common clinical problems. In Sweden, they are usually handled by nurses as part of public Child Health Centre care. Severe cases are referred to child psychiatry services. This randomized controlled trial compared two groups of mother–infant dyads in a Stockholm sample. One received only Child Health Centre care (the “CHCC” group) while the other received mother–infant psychoanalytic treatment plus CHCC (the “MIP” group). Eighty dyads of mothers and infants under 1½ years of age where the mothers had serious concerns about themselves in their role as mothers, their infants' well‐being, or the mother–baby relationship were randomly selected for either the MIP or the CHCC group. The primary outcomes were mother‐reported depression, mother‐reported infant functional problems, and interviewer‐based relationship assessments, all at 6 months after joining the project. Secondary outcomes were mother‐reported stress and general psychic distress, externally rated video‐recorded interactions, and the consumption of healthcare at the CHC, again all after 6 months. Intent‐to‐treat analyses of Treatment × Time effects significantly favored MIP treatment for maternal depression, mother–infant relationships, and maternal sensitivity. Effects were nearly significant on maternal stress, but nonsignificant on mother‐reported infant functional problems, general psychic distress, maternal interactive structuring and nonintrusiveness, infant responsiveness and involvement, and healthcare consumption. MIP treatment improved mother–infant relationships and maternal sensitivity and depression, all of which are known to influence child development. If effects persist and are reproduced, MIP treatment holds promise for more widespread use.     

Diagnosing fatigue in gait patterns by support vector machines and self-organizing maps

The aim of the study was to train and test support vector machines (SVM) and self-organizing maps (SOM) to correctly classify gait patterns before, during and after complete leg exhaustion by isokinetic leg exercises. Ground reaction forces were derived for 18 gait cycles on 9 adult participants. Immediately before the trials 7–12, participants were required to completely exhaust their calves with the aid of additional weights (44.4 ± 8.8 kg). Data were analyzed using: (a) the time courses directly and (b) only the deviations from each individual’s calculated average gait pattern. On an inter-individual level the person recognition of the gait patterns was 100% realizable. Fatigue recognition was also highly probable at 98.1%. Additionally, applied SOMs allowed an alternative visualization of the development of fatigue in the gait patterns over the progressive fatiguing exercise regimen.     

Building a Committed Hospice Volunteer Workforce—Do Variables at the Experience Stage Matter?

Volunteers are crucial to the survival of non‐profit organisations, who therefore have a fundamental interest in sustaining voluntary engagement over time. A central variable regarding sustained voluntary engagement is volunteers' organisational commitment, which has so far been a neglected research issue. The study at hand therefore explicitly focuses on hospice volunteers' commitment. Starting from the assumption that variables at the experience stage of volunteerism may be relevant in predicting volunteer commitment, questionnaire data on volunteers' motives, motive fulfilment and role identity were collected in a sample of hospice volunteers (N = 276). Results of multiple regression analyses show positive relationships between altruistic motive fulfilment and a volunteer role identity on the one hand and volunteer commitment on the other. Observed interaction effects imply that altruistic motive fulfilment is of importance both at the initial phase of volunteering and for long‐term volunteers. Moreover, interaction effects provide evidence that the fulfilment of egoistic motives is of particular importance amongst volunteers to whom egoistic motives are central. Thus, the fulfilment of altruistic motives and facilitating the development of a volunteer role identity should be permanent concerns in building a committed workforce. Egoistic motive fulfilment in contrast is of special relevance, when egoistic motives for volunteering are strong. Copyright © 2014 John Wiley & Sons, Ltd.     

Fathers' versus mothers' social referencing signals in relation to infant anxiety and avoidance: a visual cliff experiment

Infants use signals from others to guide their behavior when confronted with novel situations, a process called ‘social referencing’ (SR). Via SR, signs of parental anxiety can lead to infant anxiety. Little is known about differences in the effect of paternal and maternal SR signals on child anxiety. Using a visual cliff paradigm, we studied whether SR processes between fathers and their infants differed from mothers and their infants. Eighty‐one infants aged 10–15 months were randomly assigned to conduct the visual cliff task with their father (n = 41) or mother (n = 40). The infant was placed on the shallow side of the cliff and the parent, standing at the deep side, was instructed to encourage the infant to cross. Results showed that although mothers showed more intense facial expressions of encouragement than fathers, no differences occurred in how fast, and with how much anxiety, infants crossed the cliff with fathers and mothers. However, path analyses showed that paternal, but not maternal, expressed anxiety was positively associated with infant expressed anxiety and avoidance. For infants who participated with their mother, infants' anxious temperament was negatively associated with infant avoidance of the cliff. Infant anxious temperament moderated the link between paternal expressed anxiety and infant avoidance: the higher the level of infant anxious temperament the stronger the positive association between paternal expressed anxiety and infant's avoidance of the cliff. Lastly, parental encouragement was unrelated to infant expressed anxiety and avoidance. Our results suggest that SR processes between fathers and their infants differ from those between mothers and their infants.