False memories and lexical decision: even twelve primes do not cause long-term semantic priming

Semantic priming effects are usually obtained only if the prime is presented shortly before the target stimulus. Recent evidence obtained with the so-called false memory paradigm suggests, however, that in both explicit and implicit memory tasks semantic relations between words can result in long-lasting effects when multiple 'primes' are presented. The aim of the present study was to investigate whether these effects would generalize to lexical decision. In four experiments we showed that even as many as 12 primes do not cause long-term semantic priming. In all experiments, however, a repetition priming effect was obtained. The present results are consistent with a number of other results showing that semantic information plays a minimal role in long-term priming in visual word recognition.     

Context and the interpretation of likelihood information: the role of intergroup comparisons on perceived vulnerability

Four experiments investigated how people's perceptions about a group's (e.g., women's) vulnerability to a disease are influenced by information about the prevalence of the disease in a comparable group (e.g., men). Participants read symptom and prevalence infomation about fictitious diseases before answering questions regarding target group vulnerability. Participants used the prevalence rate for a nontarget group as an immediate comparison standard for intuitively interpreting the degree of vulnerability of a target group, resulting in robust contrast effects. Experiments 3 and 4 illustrated that these contrast effects can cause a person's intuitive perceptions about a group's vulnerability to selected diseases to conflict with his or her knowledge of the prevalence rates for the diseases. The results support a distinction between 2 components of psychological uncertainty-beliefs in objective probability and more intuitive perceptions of certainty.     

Ability evaluation by proxy: role of maximal performance and related attributes in social comparison

Four experiments tested the effects of information about a proxy's related attributes and maximal effort in social comparisons of ability. In Study 1, a proxy's prior performance at maximal effort exerted systematic effects on participants' personal performance predictions for a novel task. When information about the proxy's effort was ambiguous (Study 2). information about related attribute similarity was used in the formulation of performance predictions. In Studies 3 and 4, 2-way interaction terms revealed that participants used related attribute information in generating performance predictions when the proxy's maximum effort was unknown. However, related attribute information was disregarded when proxy's maximum effort was unambiguous. Results were consistent with the proxy comparison model of ability self-evaluation (L. Wheeler, R. Martin, & J. Suls, 1997).     

Encoding specificity manipulations do affect retrieval from memory

In a recent article, P.A. Higham (2002) [Strong cues are not necessarily weak: Thomson and Tulving (1970) and the encoding specificity principle revisited. Memory &Cognition, 30, 67-80] proposed a new way to analyze cued recall performance in terms of three separable aspects of memory (retrieval, monitoring, and report bias) by comparing performance under both free-report and forced-report instructions. He used this method to derive estimates of these aspects of memory in an encoding specificity experiment similar to that reported by D.M. Thomson and E. Tulving (1970) [Associative encoding and retrieval: weak and strong cues. Journal of Experimental Psychology, 86, 255-262]. Under forced-report instructions, the encoding specificity manipulation did not affect performance. Higham concluded that the manipulation affected monitoring and report bias, but not retrieval. I argue that this interpretation of the results is problematic because the Thomson and Tulving paradigm is confounded, and show in three experiments using a more appropriate design that encoding specificity manipulations do affect performance in forced-report cued recall. Because in Higham's framework forced-report performance provides a measure of retrieval that is uncontaminated by monitoring and report bias it is concluded that encoding specificity manipulations do affect retrieval from memory.     

Visual short-term memory load suppresses temporo-parietal junction activity and induces inattentional blindness

The right temporo-parietal junction (TPJ) is critical for stimulus-driven attention and visual awareness. Here we show that as the visual short-term memory (VSTM) load of a task increases, activity in this region is increasingly suppressed. Correspondingly, increasing VSTM load impairs the ability of subjects to consciously detect the presence of a novel, unexpected object in the visual field. These results not only demonstrate that VSTM load suppresses TPJ activity and induces inattentional blindness, but also offer a plausible neural mechanism for this perceptual deficit: suppression of the stimulus-driven attentional network.     

Enemies and friends in the neighborhood: orthographic similarity effects in semantic categorization

Studies investigating orthographic similarity effects in semantic tasks have produced inconsistent results. The authors investigated orthographic similarity effects in animacy decision and in contrast with previous studies, they took semantic congruency into account. In Experiments 1 and 2, performance to a target (cat) was better if a previously studied neighbor (rat) was congruent (i.e., belonged to the same animate-inanimate category) than it was if it was incongruent (e.g., mat). In Experiments 3 and 4, performance was better for targets with more preexisting congruent neighbors than for targets with more preexisting incongruent neighbors. These results demonstrate that orthographic similarity effects in semantic categorization are conditional on semantic congruency. This strongly suggests that semantic information becomes available before orthographic processing has been completed.     

Epidemiological Measurement of Children's and Adolescents' Exposure to Community Violence: Working with the Current State of the Science

A number of measures have been used in epidemiological studies of children's exposure to community violence, yet the quality of these instruments is not uniformly good. This paper undertakes a systematic review of the most commonly used (or most promising) self-report or interview-administered instruments, with regard to their conceptual bases and psychometric properties. Based on the review, recommendations are made for working with the current state of the science in order to move the field forward. A key recommendation is for sounder conceptualization of work in the field and greater transparency in the reporting of research, in order to facilitate the comparability of studies.     

Postextinction infusion of a mitogen-activated protein kinase inhibitor into the medial prefrontal cortex impairs memory of the extinction of conditioned fear

We investigated whether postextinction training infusion of PD098059, a selective inhibitor of mitogen-activated protein kinase (MAPK) activation, into the medial prefrontal cortex, would impair retention of extinction learning in rats. We found that immediate, but not late (2 or 4 h), postextinction infusion of PD098059 provoked a full return of conditioned freezing. These results suggest that activation of prefrontal MAPK in early stages of postextinction training participates in processes that protect against spontaneous recovery of aversive responses.     

Sensorimotor simulations underlie conceptual representations: Modality-specific effects of prior activation

According to the perceptual symbols theory (Barsalou, 1999), sensorimotor simulations underlie the representation of concepts. Simulations are componential in the sense that they vary with the context in which the concept is presented. In the present study, we investigated whether representations are affected by recent experiences with a concept. Concept names (e.g., APPLE) were presented twice in a property verification task with a different property on each occasion. The two properties were either from the same perceptual modality (e.g.,green, shiny) or from different modalities (e.g.,tart, shiny). All stimuli were words. There was a lag of several intervening trials between the first and second presentation. Verification times and error rates for the second presentation of the concept were higher if the properties were from different modalities than if they were from the same modality.     

Allophonic mode of speech perception in dyslexia

Perceptual discrimination between speech sounds belonging to different phoneme categories is better than that between sounds falling within the same category. This property, known as "categorical perception," is weaker in children affected by dyslexia. Categorical perception develops from the predispositions of newborns for discriminating all potential phoneme categories in the world's languages. Predispositions that are not relevant for phoneme perception in the ambient language are usually deactivated during early childhood. However, the current study shows that dyslexic children maintain a higher sensitivity to phonemic distinctions irrelevant in their linguistic environment. This suggests that dyslexic children use an allophonic mode of speech perception that, although without straightforward consequences for oral communication, has obvious implications for the acquisition of alphabetic writing. Allophonic perception specifically affects the mapping between graphemes and phonemes, contrary to other manifestations of dyslexia, and may be a core deficit.