Supporting Mechanical Reasoning with a Representationally‐Rich Learning Environment

A learning environment to support mechanical reasoning and understanding of simple machines for middle school and high school students is presented, along with results of an evaluation of its effectiveness in student learning. Based on recommendations from literature on instructional frameworks and cognitive aspects of mechanical reasoning, SIMALE (the Simple Machines Learning Environment) was designed to support reflection, collaboration, and presentation of concepts from multiple perspectives. SIMALE was implemented with a diverse population of middle and high school students with three treatment variations: (1) environment with focus on Lego exercises to engage in hands‐on physical activities, (2) environment with focus on a Web‐based computer module, and (3) environment with both the computer module and Lego exercises. Analyses of results show significant increases in post‐test performance for all treatment variations within SIMALE. The results also revealed unexpected dramatic results in equalizing post‐test scores along ethnic and gender dimensions, in spite of large population differences in pre‐test scores.     

Sourdough in gluten-free bread-making: An ancient technology to solve a novel issue?

The increasing demand for high quality gluten-free (GF) bread, clean labels and natural products is raising the need for new approaches in GF bread-making. Sourdough is the foremost fermentation used for baking purposes and it has been proven to be ideal for improving the texture, palatability, aroma, shelf life and nutritional value of wheat and rye breads. These characteristic features derive from the complex metabolic activities of the sourdough-resident lactic acid bacteria and yeasts, e.g. acidification, production of exopolysaccharides, proteolytic- amylolytic- and phytase activity, and production of antimicrobial substances. These effects have been extensively studied and well described for traditional baking, whereas little is known about the role of sourdough in GF baking. Yet, the microbiological and qualitative characterisation of local GF fermented products indicate an overlap with the microbiota of wheat/rye fermentation and suggest that the positive metabolic activities of the sourdough microbiota are still retained during fermentation of GF crops. Thus, the use of sourdough in GF baking may be the new frontier for improving the quality, safety and acceptability of GF bread.     

Effects of Word Frequency and Contextual Richness on Children's Word Identification Abilities.

To examine the interaction effects of word frequency and contextual richness on word identification, 36 first-grade and 36 third-grade subjects were asked to guess a word that fit into a blank space in sentences which varied in terms of contextual richness. The target word was one member of a pair of high-versus low-frequency synonyms. Beginning with the first letter in a word, each incorrect guess prompted an additional letter cue. The results of a balanced repeated measures design indicated significant main effects for grade level, word frequency, and context and a Frequency × Context interaction, which suggests that contextual richness is more pronounced for high-frequency words and that redundancy models of reading ought to incorporate the notion of response availability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Causal inferences about communicators and their effect on opinion change.

An attribution analysis of opinion change viewed message persuasiveness as a function of inferred communicator biases. Recipients infer a knowledge bias (KB) by believing that a communicator's knowledge about external reality is nonveridical and a reporting bias (RB) by believing that a communicator's willingness to convey an accurate version of external reality is compromised. In an experiment with 355 undergraduates, KB expectancies were established by portraying a communicator as having a strong commitment to values represented by the probusiness or proenvironment side of a controversial issue and RB expectancies by portraying his audience as having a strong commitment to one or the other side. In all conditions, the communicator advocated the proenvironment position. Therefore, recipients' expectancies were confirmed in the context of a proenvironment communicator and/or audience and disconfirmed in the context of a probusiness communicator and/or audience. Regardless of the type of bias that Ss expected, they were more persuaded and rated the communicator as more unbiased when their expectancies were disconfirmed. Confirmation of expectancies based on RB, but not KB, was associated with inferences of communicator insincerity and manipulativeness. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Elaborative verbal rehearsals and college students' cognitive performance.

Two experiments were conducted to determine the potential of elaborative verbal rehearsal (EVR) as a learning strategy for high-risk college students. In Exp 1, a correlational inquiry was used to explore the relation between Ss' EVRs and their overall test performance. Sixty-four Ss studied an extended text, prepared an EVR, and then took the test. There were significant correlations between the quality of Ss' EVRs and their overall test performance. In Exp 2, 50 Ss were trained to produce either EVRs or verbatim rehearsals and then took the same test in immediate and delayed conditions. The EVR Ss performed significantly better on almost every variable. EVRs appear to be a powerful learning strategy for high-risk students. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Asymmetry of happiness and sadness in effects on memory in normal college students: Comment on Hasher, Rose, Zacks, Sanft, and Doren.

Research suggests that, whereas induced happiness tends to facilitate the recall of positive material, induced mild sadness often does not facilitate the recall of negative material symmetrically. These results are compatible with those reported by L. Hasher et al (see record 1986-03061-001) but also suggest that their failure to observe effects of mild depression on recall should not be overgeneralized to conclude that affective states other than mild sadness have negligible effects on cognitive processes. Possible mediators of these phenomena are discussed, and their potential relevance to the understanding of clinical depression and of the cognitive representation of various affective states is considered. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cognitive profiles of difficult-to-remediate and readily remediated poor readers: Early intervention as a vehicle for distinguishing between cognitive and experiential deficits as basic causes of specific reading disability.

Reading impaired first graders were given daily tutoring as a "first cut" diagnostic to aid in distinguishing between reading difficulties caused by basic cognitive deficits and those caused by experiential deficits. Reading achievement in most of these children was found to be within or above the average range after one semester of remediation. Children who were difficult to remediate performed below both children who were readily remediated and normal readers on kindergarten and first-grade tests evaluating phonological skills, but not on tests evaluating visual, semantic and syntactic skills. The results are consistent with convergent findings from previous research suggesting that reading problems in some poor readers may be caused primarily by phonological deficits. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cognitive operations and the generation effect.

The present experiments were designed to test a cognitive operations hypothesis of the generation effect, or memorial advantage for stimuli that are generated rather than simply read. In two experiments two aspects of generation were manipulated independently: (a) whether the to-be-remembered stimulus was absent (and therefore produced by the subject) or present (and therefore not produced) and (b) whether the relevant cognitive operations were performed by the subject or were instead performed by another agent. Specifically, subjects were given simple multiplication problems with the answers either absent or present in the original problems and with the calculations performed either by themselves or by another agent (either the experimenter or a calculator). The first experiment tested immediate recall of the answers, and the second experiment tested both recall and recognition of the answers after retention intervals up to a week. In all cases, a highly significant retention advantage was found for the tasks requiring multiplication operations by the subjects themselves as opposed to another agent, but there was no main effect for whether the answer was absent or present in the original problem. We discuss the theoretical implications of these results with respect to the generation effect as well as the practical implications with respect to using a calculator in learning the multiplication facts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)