The vocabulary spurt predicts the emergence of backward semantic inhibition in 18‐month‐old toddlers

The current study examines the relationship between 18‐month‐old toddlers’ vocabulary size and their ability to inhibit attention to no‐longer relevant information using the backward semantic inhibition paradigm. When adults switch attention from one semantic category to another, the former and no‐longer‐relevant semantic category becomes inhibited, and subsequent attention to an item that belongs to the inhibited semantic category is impaired. Here we demonstrate that 18‐month‐olds can inhibit attention to no‐longer relevant semantic categories, but only if they have a relatively large vocabulary. These findings suggest that an increased number of items (word knowledge) in the toddler lexical‐semantic system during the “vocabulary spurt” at 18‐months may be an important driving force behind the emergence of a semantic inhibitory mechanism. Possessing more words in the mental lexicon likely results in the formation of inhibitory links between words, which allow toddlers to select and deselect words and concepts more efficiently. Our findings highlight the role of vocabulary growth in the development of inhibitory processes in the emerging lexical‐semantic system.     

Metacognitive scaffolding boosts cognitive and neural benefits following executive attention training in children

Interventions including social scaffolding and metacognitive strategies have been used in educational settings to promote cognition. In addition, increasing evidence shows that computerized process‐based training enhances cognitive skills. However, no prior studies have examined the effect of combining these two training strategies. The goal of this study was to test the combined effect of metacognitive scaffolding and computer‐based training of executive attention in a sample of typically developing preschoolers at the cognitive and brain levels. Compared to children in the regular training protocol and an untrained active control group, children in the metacognitive group showed larger gains on intelligence and significant increases on an electrophysiological index associated with conflict processing. Moreover, changes in the conflict‐related brain activity predicted gains in intelligence in the metacognitive scaffolding group. These results suggest that metacognitive scaffolding boosts the influence of process‐based training on cognitive efficiency and brain plasticity related to executive attention.     

Knowledge,safety, and Gettierized lottery cases: Why mere statistical evidence is not a (safe) source of knowledge

The lottery problem is the problem of explaining why mere reflection on the long odds that one will lose the lottery does not yield knowledge that one will lose. More generally, it is the problem of explaining why true beliefs merely formed on the basis of statistical evidence do not amount to knowledge. Some have thought that the lottery problem can be solved by appeal to a violation of the safety principle for knowledge, i.e., the principle that if S knows that p, not easily would S have believed that p without p being the case. Against the standard safety‐based solution, I argue that understanding safe belief as belief that directly covaries with the truth of what is believed in a suitably defined set of possible worlds forces safety theorists to make a series of theoretical choices that ultimately prevent a satisfactory solution to the problem. In this way, I analyze several safety principles that result from such choices—the paper thus gives valuable insights into the nature of safety—and explain why none solves the lottery problem, including their inability to explain away Gettierized lottery cases. On a more positive note, I show that there is a viable solution in terms of safety if we get rid of the unquestioned assumption that safe beliefs directly track the truth. The alternative is a conception of safe belief according to which what safe beliefs directly track is the appropriateness of the circumstances and, indirectly, the truth. The resulting safety principle, I argue, explains why mere statistical evidence is not a safe source of knowledge.     

Acquisition of joint attention by olive baboons gesturing toward humans

Animal Cognition - Joint attention is a core ability of human social cognition which broadly refers to the coordination of attention with both the presence and activity of social partners. In both...