A versatile electronic switch with memory

This noise-conditioned switch provides a convenient interface between S response switches and logic circuitry and is adaptable to many experimental situations.     

Network Connectivity Dynamics,Cognitive Biases,and the Evolution of Cultural Diversity in Round-Robin Interactive Micro-Societies

The distribution of cultural variants in a population is shaped by both neutral evolutionary dynamics and by selection pressures. The temporal dynamics of social network connectivity, that is, the order in which individuals in a population interact with each other, has been largely unexplored. In this paper, we investigate how, in a fully connected social network, connectivity dynamics, alone and in interaction with different cognitive biases, affect the evolution of cultural variants. Using agent-based computer simulations, we manipulate population connectivity dynamics (early, mid, and late full-population connectivity); content bias, or a preference for high-quality variants; coordination bias, or whether agents tend to use self-produced variants (egocentric bias), or to switch to variants observed in others (allocentric bias); and memory size, or the number of items that agents can store in their memory. We show that connectivity dynamics affect the time-course of variant spread, with lower connectivity slowing down convergence of the population onto a single cultural variant. We also show that, compared to a neutral evolutionary model, content bias accelerates convergence and amplifies the effects of connectivity dynamics, while larger memory size and coordination bias, especially egocentric bias, slow down convergence. Furthermore, connectivity dynamics affect the frequency of high-quality variants (adaptiveness), with late connectivity populations showing bursts of rapid change in adaptiveness followed by periods of relatively slower change, and early connectivity populations following a single-peak evolutionary dynamic. We evaluate our simulations against existing data collected from previous experiments and show how our model reproduces the empirical patterns of convergence.     

Perceived Racism and Suicide Ideation: Mediating Role of Depression but Moderating Role of Religiosity among African American Adults

Suicide is a public health problem for African Americans who are young and of working age. The purpose of this study was to examine mediated and moderated effects of perceived racism on suicide ideation in a community sample of 236 African American men and women. Measures of suicide ideation, depression symptoms, intrinsic/extrinsic religiosity, and perceived racism were administered. Perceived racial discrimination was directly and indirectly associated with suicide ideation. For participants who reported low levels of extrinsic religiosity, the mediated effect of perceived racism (via depression symptoms) was significant. These findings provide some insight into suicide vulnerability for specific subgroups of African Americans.     

The Opportunity Cost of Compulsory Research Participation: Why Psychology Departments Should Abolish Involuntary Participant Pools

Science and Engineering Ethics - Psychology departments often require undergraduates to participate in faculty and graduate research as part of their course or face a penalty. Involuntary...