Inactivation of the ventral tegmental area abolished the general excitatory influence of Pavlovian cues on instrumental performance

Pavlovian stimuli can markedly elevate instrumental responding, an effect known as Pavlovian-instrumental transfer (PIT). As the role of the ventral tegmental area (VTA) in PIT is yet unknown, we examined the effects of transient VTA inactivation by direct microinjections of a mixture of the GABA(A) and GABA(B) receptor agonists, muscimol and baclofen. Results reveal that PIT, i.e., the increase in instrumental responding during presentation of a Pavlovian stimulus, was abolished by intra-VTA microinjections of muscimol/baclofen. These data provide the first evidence that the VTA mediates Pavlovian influences on instrumental behavior.     

Wissenschaftstheorie der grazer schule: Meinong und Frankl

Ohne Zusammenfassung     

Preparing the Ground for Kant’s Highest Good in the World

Philosophia - In his new book, Rossi (2019) emphasizes the prominent role of enlightened religion in the political project of establishing perpetual peace. My paper discusses Rossi’s stance...     

Peace and Islam: In theory and practice

The article centres on the humanistic and peace‐oriented elements in the foundational sources of Islam, the Qur'an and the Prophet's life, especially on Muhammad's attitude towards war and peace. As the Qur'an clearly attests, Muhammad continued to search for reconciliation and mutual understanding,. with Jews and Christians as well as with opponents and enemies. As to jihad, Q. 2:90 and Q. 22:39 unambiguously prohibit offensive war, in fact, any kind of aggression, cruelty and wanton destruction. The Qur'an prescribes a humane conduct of war. Wherever politically possible, peace has the priority. Finally, the author exemplifies contemporary Muslim attitudes towards war and peace and describes Muslim peace initiatives.     

Anticipatory nausea in cancer patients receiving chemotherapy: Classical conditioning etiology and therapeutical implications

The delivery of cytotoxic drugs in cancer treatment is often accompanied by posttreatment side effects (e.g., nausea). Moreover, there is evidence that cancer patients are at risk to develop these side effects in anticipation of chemotherapy (i.e., anticipatory nausea [AN]). AN can be explained as the result of a classical conditioning process with the cytotoxic drug as the unconditioned stimulus (US). Stimuli paired with the US (e.g., smells, tastes) can become conditioned stimuli (CSs) eliciting AN as the conditioned response (CR). The present study was conducted to test whether AN shows characteristics of a CR. Fifty-five ambulatory cancer patients were asked to record nine kinds of physical symptoms (e.g., nausea, vomiting, sweating) on time-scheduled symptom lists: after an infusion (indicating posttreatment symptoms) and prior to their next infusion (indicating anticipatory symptoms). Each measurement period covered a maximum of 48 hours. AN was reported by ten patients (18.08%). Data revealed (a) a statistically significant association between posttreatment nausea and vomiting, respectively, and AN; (b) the occurrence of AN increased with drug emetogenity (i.e., US-intensity); and (c) the duration of AN increased with temporal proximity to the infusion. The results support the conditioning model. Thus, it is proposed to prevent AN by classical conditioning techniques (e.g., overshadowing).     

When does self-reported prosocial motivation predict helping? The moderating role of implicit prosocial motivation

In three studies, we tested a motivational model to predict different types of helping from an interactionist, dual-system perspective. We argued that helping behavior is determined by the interplay of two distinct motivational systems: the explicit (i.e., conscious) and the implicit (i.e., unconscious). In line with previous research we expected that explicit prosocial motivation relates to helping, and additionally proposed that depending on the type of helping this relationship is moderated by implicit prosocial motivation: For planned helping, explicit prosocial motivation is a sufficient predictor, regardless of implicit prosocial motivation. For spontaneous helping, on the other hand, the effect of explicit prosocial motivation is moderated by implicit prosocial motivation, and only predictive when also implicit prosocial motivation is high. Study 1 (207 Dutch participants, M _age  = 51.7 years; 51.7 % female) with self-reported willingness to help as dependent variable confirmed that planned helping was determined by explicit prosocial motivation, whereas its effect on spontaneous helping was moderated by implicit prosocial motivation. Study 2 (193 U.S. participants, M _age  = 35.2 years; 64.2 % female) with real-life measures of planned help confirmed the hypothesized main effect of explicit prosocial motivation. Study 3 (73 Dutch participants, M _age  = 20.8 years; 68.5 % female) with a real-life measure of spontaneous helping confirmed the moderating role of implicit prosocial motivation, as the effect of explicit prosocial motivation on helping was only significant for individuals with high implicit prosocial motivation. We argue that considering implicit prosocial motivation provides an overlooked avenue for a more systematic investigation of helping.     

Perception and production of object-related grasping in 6-month-olds

In this study, 6-month-olds’ perception of an object-related human grasping action was compared with their level of grasping performance using a within-participants design. In the action perception task, infants were presented with the video of an actor’s grasping movement toward an occluded target object. Subsequently, an expected and an unexpected final state of this grasping movement were presented simultaneously, and infants’ looking times were measured. In the action production task, infants were presented with three graspable objects. Infants’ grasping behavior was coded to be either palmar or thumb-opposite grasping. Results indicate that infants who were already able to perform a thumb-opposite grasp differentiated between the two final states in the action perception task by looking longer toward the unexpected final state. In contrast, infants who showed only palmar grasps looked equally long toward both final states. This finding supports the assumption that action perception and action control are already closely related in infants as young as 6 months.     

The strategic regulation of children's memory performance and suggestibility

We report two empirical studies that investigated previously reported benefits of a high accuracy motivation, and thus a high threshold, for children's and adults' event recall and for their ability to resist false suggestions. In the studies, 6-, 7-, and 8-year-olds, as well as adults, were shown a brief video about an event and were later asked unbiased and misleading questions about it. In Study 1, participants were either (a) given the typical accuracy instructions (including the option to answer with "I don't know"), (b) reminded of the accuracy instructions during the interview, or (c) immediately given feedback and a token for every correct answer. The results showed that the reminders were ineffective in stimulating strategic control behavior in children, independent of age. In Study 2, the confounding effects of feedback and incentives were disentangled by contrasting (a) free report, (b) feedback only, (c) incentives only, and (d) feedback plus incentives. Analyses on recall performance and suggestibility revealed that both feedback and incentives are necessary to increase children's accurate memory reports.