Are incorrect judgments on false belief tasks better explained within the framework of a conceptual change theory or a bias theory? Conceptual change theory posits a change in the form of reasoning from 3 to 4 years old while bias theory posits that processing factors are responsible for errors among younger children. The results from three experiments showed that children who failed a test of false belief took as long to respond as those who passed, and both groups of children (...) took longer to respond to belief questions than to questions about prior states of reality. These results seem to support the bias theory. (shrink)
Organogenesis and metamorphosis require the intricate orchestration of multiple types of cellular interactions and signaling pathways. Glutamate (Glu) is an excitatory extracellular signaling molecule in the nervous system, while Ca2+ is a major intracellular signaling molecule. The first Glu receptors to be cloned are Ca2+‐permeable receptors in mammalian brains. Although recent studies have focused on Glu signaling in synaptic mechanisms of the mammalian central nervous system, it is unclear how this signaling functions in development. Our recent article demonstrated that Ca2+‐permeable (...) AMPA‐type Glu receptors (GluAs) are essential for formation of a photosensitive organ, development of some neurons, and metamorphosis, including tail absorption and body axis rotation, in ascidian embryos. Based on findings in these embryos and mammalian brains, we formed several hypotheses regarding the evolution of GluAs, the non‐synaptic function of Glu, the origin of GluA‐positive neurons, and the neuronal network that controls metamorphosis in ascidians. (shrink)