I Can But I Shall Not Always Be Empathic.

Empathy, a core process for social interactions, is the capacity to understand and share others' mental states and emotions. Each individual is thought to have a maximum level of empathy (empathic ability) and a spontaneous tendency to express it (empathic propensity), which can be affected by multiple factors. Two within-subject studies were conducted to assess the malleability of empathy by modulating contextual factors and measuring their interaction with psychological characteristics. In Study 1, 59 healthy adults evaluated their empathy for people showing facial expressions of pain following different instructions: Passive Observation and Instruction to Actively Empathize. In Study 2, 56 healthy adults performed a similar task under two conditions: Passive Observation and Observation under a Cognitive Load. The results revealed that empathy was significantly increased in the actively empathizing condition (Study 1) and under a cognitive load, but more importantly for men (Study 2). The level of change between the two conditions was associated with self-reported empathy, autistic, alexithymia and psychopathic traits (Study 1), as well as with working memory capacities and the level of empathy reported in the passive observation condition (Study 2). These findings suggest that an instruction to actively empathize and, surprisingly, a cognitive load can both increase empathy, but not for the same individuals. An instruction to actively empathize seems to increase empathy for individuals with good empathic dispositions, while a cognitive load enhances empathy in people for which empathic propensity is sub-optimal.

The effect of tDCS over the right temporo-parietal junction on pain empathy.

Empathy is a complex psychological phenomenon crucial for social perception and interactions. Several lines of evidence suggest that the right temporo-parietal junction is involved in self-other control mechanisms that play an important role in empathic responses. However, limited direct evidence of the involvement of this region in empathic responses is currently available. In this study, inhibitory transcranial direct current stimulation over this region influenced empathic responses to others' pain. It was found that compared to participants that received anodal or sham transcranial direct current stimulation, participants who received cathodal transcranial direct current stimulation over the right temporo-parietal junction perceived the pain of others as less intense compared to sham stimulation and showed decreased late event related potentials to facial expressions of pain. Furthermore, it was found the stimulation had no significant effect on measures of sensorimotor resonance and physiological responses to pain in others. Our results demonstrate that the right temporo-parietal junction plays a role in empathic responses and that its inhibition can decrease behavioural and cerebral measures related to the cognitive-evaluative component of empathy. It is proposed that the right temporo-parietal junction is a valid stimulation target to study the influence of self-other control in empathic processes and could be useful to study the involvement of this region observed in clinical conditions characterized by altered empathic responses.

Flow around a rotating, semi-infinite cylinder in an axial stream.

This paper concerns steady, high-Reynolds-number flow around a semi-infinite, rotating cylinder placed in an axial stream and uses boundary-layer type of equations which apply even when the boundary-layer thickness is comparable to the cylinder radius, as indeed it is at large enough downstream distances. At large rotation rates, it is found that a wall jet appears over a certain range of downstream locations. This jet strengthens with increasing rotation, but first strengthens then weakens as downstream distance increases, eventually disappearing, so the flow recovers a profile qualitatively similar to a classical boundary layer. The asymptotic solution at large streamwise distances is obtained as an expansion in inverse powers of the logarithm of the distance. It is found that the asymptotic radial and axial velocity components are the same as for a non-rotating cylinder, to all orders in this expansion.