Differences in cortical activity related to motor planning between experienced guitarists and non-musicians during guitar playing

The influence of motor skill learning on movement-related brain activity was investigated using electroencephalography. Previous research has indicated that experienced performers display movement-related cortical potentials (MRCPs) of smaller amplitude and later onset compared to novices. Unfortunately, previous studies have lacked ecological validity with experimenters recording the MRCP prior to simple motor tasks and applying the results to more complex motor skills. This study replicated previous research using an ecologically valid motor skill; recording the MRCP from a group of experienced guitarists and a control group of non-musicians while they played a simple scale on the guitar. Results indicated no difference between groups in early motor planning. In contrast, the later, negative slope and motor potential components were of smaller amplitude and the negative slope began later in the experienced guitarists. The data may indicate that, for experienced guitarists, a reduced level of effort is required during the motor preparation phase of the task. These findings have implications for musical instrument learning as well as motor skill acquisition in general.     

Strong reciprocity is real, but there is no evidence that uncoordinated costly punishment sustains cooperation in the wild

I argue in my target article that field evidence does not support the costly punishment hypothesis. Some commentators object to my reading of the evidence, while others agree that evidence in favour of costly punishment is scant. Most importantly, no rigorous measurement of cost-benefit ratios in the field has been attempted so far. This lack of evidence does not rule out costly punishment as a cause of human cooperation, but it does pre-empt some overconfident claims made in the past. Other commentators have interpreted my article as an anti-experimental pamphlet or as a flat denial of the existence of pro-social motives--which it was not intended to be. While we have enough data to establish the existence (and theoretical relevance) of strong reciprocity motives, I argue in this response that their efficacy (and policy relevance) has not been demonstrated.     

Picture‐IAT versus Word‐IAT: level of stimulus representation influences on the IAT

The Implicit Association Test is a paradigm designed to assess individual differences in implicit cognition. The goal of this report was to examine the reasons for discrepant effect magnitudes obtained with two presumably interchangeable versions: Picture‐IAT (P‐IAT) and Word‐IAT (W‐IAT). We show that this discrepancy is due to the relation between stimuli and referent category: the level of representation (LR) at which a stimulus represents an intended category. Experiment 1 replicates the discrepancies found in previous research. Experiments 2–4 show that increasing the LR of stimuli increases the IAT effect. LR affects the magnitude of the IAT effect even when modality and other features of the stimuli are kept constant. The utility of LR for future investigations examining the IAT paradigm is discussed. Copyright © 2009 John Wiley & Sons, Ltd.     

Buying a passport to heaven: Usury,restitution, and the merchants of medieval Genoa

Historians have argued that the ecclesiastic ban on loans at interest delayed the development of capital markets in the middle ages, and have supported this by pointing to well-documented cases of restitutions of usurious gains by famous moneylenders. Strictly, however, such evidence does not prove that usury laws affected lending, because donations by rich bankers may reflect other motivations. If usury laws had an impact, we have to exclude the Medicis or the Fuggers from the sample, and look for it among the small moneylenders of medieval Europe. Data from late medieval Genoa show that donations by merchants were no greater than those of the population at large once personal wealth is accounted for. However, among merchants the value of pious bequests correlates more closely with mercantile activity than personal wealth, a finding that supports the view that usury laws created an effective constraint on medieval capital markets.     

The influence of responsibility and guilt on naive hypothesis-testing

Three experiments were used to investigate individuals' hypothesis-testing process as a function of moral perceived utilities, which in turn depend on perceived responsibility and fear of guilt. Moral perceived utilities are related to individuals' moral standards and specifically to people's attempt to face up to their own responsibilities, and to avoid feeling guilty of irresponsibility. The results showed that responsibility and fear of guilt in testing hypotheses involved a process defined as prudential mode, which entails focusing on and confirming the worst hypothesis, and then reiterating the testing process. In particular, the results showed that responsible and guilt-fearing individuals: (1) tended to search prudentially for examples confirming the worst hypothesis and to search for counter-examples falsifying the positive hypothesis; (2) focused on the worst alternative, and tended to confirm it; (3) prudentially kept up the testing process, even if faced with initial positive evidence. Our discussion of the results emphasises how people are largely pragmatic in their hypothesis testing, using efficient cognitive strategies that focus on error minimisation rather than on truth detection. In a context of responsibility and guilt, the errors are linked to people's failure to face up to their own responsibilities, and are thus moral errors.     

Psychiatric Symptoms and Quality of Life in Patients Affected by Epidermolysis Bullosa

The aim of our study was to provide a psychosocial and psychiatric evaluation of patients with epidermolysis bullosa (EB; a rare genetic disorder characterized by skin fragility), to assess psychological status, ascertain the presence of any psychiatric disorders and understand the impact of EB on quality of life. Twenty-five patients were assessed using a case record form and several standardized instruments. In 82% of patients, EB had a negative impact on quality of life and 80% of patients experienced psychiatric symptoms. Our findings revealed a high prevalence of psychosocial problems and psychiatric symptoms in patients with EB and suggested that a combined bio-psychosocial approach is the most appropriate therapeutic intervention.     

Identity concept learning in matching-to-sample tasks by tufted capuchin monkeys (Cebus apella)

The abstract concept of equivalence is considered one of the bases of higher-order cognition, and it has been the subject of considerable research in comparative cognition. This study examined the conditions under which tufted capuchin monkeys (Cebus apella) are able to acquire an identity concept. Six capuchin monkeys were trained to solve a visual matching-to-sample (MTS) task on the basis of perceptual identity. The acquisition of the identity rule was inferred from the subject’s ability to solve transfer tests with novel stimuli. We evaluated the ability of the capuchin monkeys to match the shape of novel stimuli after training with both several small stimulus sets (Experiment 1) and a large stimulus set (Experiment 2). Moreover, we examined the ability of capuchins to transfer the concept to novel visual dimensions, such as colour and size and to transfer to novel spatial arrangements of the stimuli (Experiment 2). We demonstrated that the ability of capuchins to match novel stimuli was improved by increasing the number of stimuli used during training (Experiments 1 and 2) and that after a widely applicable identity concept based on the stimulus shape was acquired, the capuchins were able to match stimuli according to an identity rule based on both the colour and size of the stimuli and when the spatial arrangement of the stimuli was varied (Experiment 2). This study is the first to demonstrate that the size of the training set affects the acquisition of an abstract identity concept in an MTS task in non-human primates.