Blocked exchanges revisited

This paper reconsiders the topic of blocked exchanges. It has been argued by some philosophers and social theorists that in order to encourage people to make donations of, e.g., blood, the sale of such items should be banned by law or public policy. In this paper I argue that (a) donations made without the option of selling are morally diminished and (b) selling such items isn't morally wrong or even insignificant in all cases since prudence (which is a moral virtue, pace Kant) may require that one sell them.     

Effects of self-evaluation on the P300 event-related potential

The effects of self evaluation on the P300 event-related potential (ERP) were explored with 56 participants (16 men, 40 women; M age = 23.4 yr., SD = 1.2) across three conditions. The conditions included (1) a standard ERP auditory oddball discrimination between a random target (15% occurrence) and standard stimuli (85% occurrence), (2) the oddball task followed by the additional cognitive task of maintaining a mental count of the target tones, and (3) the oddball task followed by the additional cognitive task of self-evaluating whether they felt surprised by the current occurrence of the target tone. The added cognitive requirements for Conditions 2 and 3 required the subjects to maintain a cognitive readiness for the secondary stimulus-related task during their sensory discrimination response for the standard oddball task. During the self-evaluation condition, the P300 amplitude was significantly larger across all recording locations than the regular oddball condition and the cognitive count condition.