Propose but verify: Fast mapping meets cross-situational word learning

We report three eyetracking experiments that examine the learning procedure used by adults as they pair novel words and visually presented referents over a sequence of referentially ambiguous trials. Successful learning under such conditions has been argued to be the product of a learning procedure in which participants provisionally pair each novel word with several possible referents and use a statistical-associative learning mechanism to gradually converge on a single mapping across learning instances [e.g., Yu, C., & Smith, L. B. (2007). Rapid word learning under uncertainty via cross-situational statistics. Psychological Science, 18(5), 414–420]. We argue here that successful learning in this setting is instead the product of a one-trial procedure in which a single hypothesized word-referent pairing is retained across learning instances, abandoned only if the subsequent instance fails to confirm the pairing – more a ‘fast mapping’ procedure than a gradual statistical one. We provide experimental evidence for this propose-but-verify learning procedure via three experiments in which adult participants attempted to learn the meanings of nonce words cross-situationally under varying degrees of referential uncertainty. The findings, using both explicit (referent selection) and implicit (eye movement) measures, show that even in these artificial learning contexts, which are far simpler than those encountered by a language learner in a natural environment, participants do not retain multiple meaning hypotheses across learning instances. As we discuss, these findings challenge ‘gradualist’ accounts of word learning and are consistent with the known rapid course of vocabulary learning in a first language.     

Factorial Validity of the Cooperative Preschool Inventory for English- and Spanish-Speaking Hispanic Children

The Cooperative Preschool Inventory (CPI) in both English and Spanish was administered to preschool Hispanic children who were monolingual in either English or Spanish. Subscales were factor-analyzed separately. When the factors were compared using coefficients of congruence, we concluded that both measures appeared to assess the same underlying construct.     

Wittgenstein and Nonsense: Psychologism,Kantianism, and the Habitus

This paper is a critical examination of Wittgenstein's view of the limits of intelligibility. In it I criticize standard analytic readings of Wittgenstein as an advocate of transcendental or behaviourist theses in epistemology; and I propose an alternative interpretation of Wittgenstein's view as a social contextualism that transcends the false dichotomy between Kantianism and psychologism. I argue that this social contextualism is strikingly similar to the social account of epistemic practices developed by Pierre Bourdieu. Through a comparison between Wittgenstein's and Bourdieu's view and an analysis of the notion of habitus , I try to show how social contextualism can account for the distinction between sense and nonsense without falling into transcendental constructivism or social behaviourism.     

A qualitative inquiry of Latino immigrants' work experiences in the Midwest

Latino immigrants are the largest source of immigrant workers in the United States. In this study, 11 first-generation Latino immigrants (8 men, 3 women) living in the Midwest were interviewed about their work experiences. Interview data were analyzed using consensual qualitative research methods (Hill, Thompson, & Williams, 1997). Five domains associated with the data included work for survival and power, work for social connections, work as self-determination, work barriers in the Midwest, and access to work in the Midwest. We identify ways in which vocational psychologists can intervene to work effectively with Latino newcomers seeking employment in the United States and to support their transition into new settlement communities. Suggestions for future research with immigrant workers are discussed.     

Neuroticism and Responsiveness to Error Feedback: Adaptive Self‐Regulation Versus Affective Reactivity

ABSTRACT Responsiveness to negative feedback has been seen as functional by those who emphasize the value of reflecting on such feedback in self‐regulating problematic behaviors. On the other hand, the very same responsiveness has been viewed as dysfunctional by its link to punishment sensitivity and reactivity. The present 4 studies, involving 203 undergraduate participants, sought to reconcile such discrepant views in the context of the trait of neuroticism. In cognitive tasks, individuals were given error feedback when they made mistakes. It was found that greater tendencies to slow down following error feedback were associated with higher levels of accuracy at low levels of neuroticism but lower levels of accuracy at high levels of neuroticism. Individual differences in neuroticism thus appear crucial in understanding whether behavioral alterations following negative feedback reflect proactive versus reactive mechanisms and processes. Implications for understanding the processing basis of neuroticism and adaptive self‐regulation are discussed.     

Aversive experiences are associated with a rapid and transient activation of ERKs in the rat hippocampus.

The extracellular signal-regulated kinases (ERKs) family of mitogen-activated protein kinases (MAPKs) has been shown to participate in memory formation. We recently found that a hippocampal ERK/MAPK cascade is required for memory formation of an inhibitory avoidance training in rats. Here we reported that this learning task is accompanied by a rapid increase in the phosphorylation of hippocampal p44 MAPK. A single mild foot shock produced a similar effect and three consecutive foot shocks provoked the activation of both p44 and p42 MAPKs. In contrast, a brief exposure to the training box or the habituation to an open field did not alter hippocampal ERK/MAPK levels. Together, these findings indicate that aversive behavioral experiences induced a rapid and transient activation of ERK/MAPKs in the hippocampus.     

A neural implementation of multi-adjoint logic programming

A neural net based implementation of propositional [0,1]-valued multi-adjoint logic programming is presented, which is an extension of earlier work on representing logic programs in neural networks carried out in [A.S. d'Avila Garcez et al., Neural-Symbolic Learning Systems: Foundations and Applications, Springer, 2002; S. Hölldobler et al., Appl. Intelligence 11 (1) (1999) 45–58]. Proofs of preservation of semantics are given, this makes the extension to be well-founded.The implementation needs some preprocessing of the initial program to transform it into a homogeneous program; then, transformation rules carry programs into neural networks, where truth-values of rules relate to output of neurons, truth-values of facts represent input, and network functions are determined by a set of general operators; the net outputs the values of propositional variables under its minimal model.     

ERK1/2 activation is necessary for BDNF to increase dendritic spine density in hippocampal CA1 pyramidal neurons

Brain-derived neurotrophic factor (BDNF) is a potent modulator of synaptic transmission and plasticity in the CNS, acting both pre- and postsynaptically. We demonstrated recently that BDNF/TrkB signaling increases dendritic spine density in hippocampal CA1 pyramidal neurons. Here, we tested whether activation of the prominent ERK (MAPK) signaling pathway was responsible for BDNF's effects on spine growth. Slice cultures were transfected with enhanced yellow fluorescent protein (eYFP) by particle-mediated gene transfer, and CA1 pyramidal neurons were imaged by laser-scanning confocal microscopy. We confirmed that BDNF (24 h) increases spine density in apical dendrites of CA1 neurons. The MEK (ERK kinase) inhibitors PD98059 and U0126 completely prevented the increase in spine density induced by BDNF, without having an effect on spine density by themselves. In contrast to its actions on cortical pyramidal neurons, BDNF had minor and rather localized effects on dendritic complexity in hippocampal pyramidal neurons, increasing the total length, but not the branching of apical dendrites within CA1 stratum radiatum, without affecting basal dendrites in stratum oriens. Our results support the hypothesis that the ERK-signaling pathway not only mediates long-term synaptic plasticity and hippocampal-dependent learning, but it is also involved in the structural remodeling of excitatory spine synapses triggered by neurotrophins.