We argue that learning about the nature and utility of scientific models and engaging in the process of creating and testing models should be a central focus of science education. To realize this vision, we created and evaluated the Model-Enhanced ThinkerTools (METT) Curriculum, which is an inquiry-oriented physics curriculum for middle school…

To investigate teachers' everyday on-the-job learning, I used a comparative case study design and examined the work of mathematics teachers in 2 high schools. Analysis of interviews, classroom observations, and teachers' conversations highlighted 3 key resources for learning: (a) reform artifacts oriented the teachers' attention to key concepts of…

Based on close observations of two 4-year-old children responding to their parents' requests for quantitative comparisons, we offer a "participationist" account of the origins and development of numerical thinking, one that portrays numbers as a product rather than a pregiven object of human communication. In parallel, we propose a…

The purpose of this study was to examine executive functioning in patients with Huntington's disease using an arithmetic word-problem-solving task including eight solvable problems of increasing complexity and four aberrant problems. Ten patients with Huntington's disease and 12 normal control subjects matched by age and education were tested.…

A particularly important aspect of executive functioning involves the ability to form and carry out complex plans, that is to say planning. This study aimed to investigate planning in 18 older and 16 younger normal participants using an ecological planning subtask derived from the Behavioural Assessment of the Dysexecutive Syndrome test battery,…

Recent clinical observations, in the absence of experimental data, appear to suggest that written expression in conduction aphasics parallels their speech (Goodglass, 1992). The current study undertakes an analysis of word level writing in two conduction aphasics, and attempts to explore the posited 'parallel' relationship between speech…

An experiment was designed to test whether or not Parkinson's disease (PD) patients were able to maintain endpoint kinematic patterns in a prehension task involving movement of the torso. Nine PD patients and nine healthy controls were asked to reach for and grasp a full cup of water that was either covered or uncovered and placed beyond the reach…

In the last decade, the Iowa Gambling Task (IGT) has become a widely employed neuropsychological research instrument for the investigation of executive function. The task has been employed in a wide range of formats, from 'manual' procedures to more recently introduced computerised versions. Computer-based formats often require that responses on…

We report evidence for dissociation between explicit and implicit access to word representations in a deep dyslexic patient (JO). JO read aloud a series of ambiguous (e.g., bank) and unambiguous (e.g., food) words and performed a lexical decision task using these same items. When required to explicitly access the items (i.e., naming), JO showed…

Object naming studies have generally observed that both normal and brain damaged individuals are faster and more accurate at identifying non-living objects than living objects (Humphreys, Riddoch, & Quinlan, 1988; Warrington & Shallice, 1984). However, a potential confounding variable, manipulability, has been present in past studies that may…

It has been claimed that the typical RVF/LH advantage for word recognition is reduced or eliminated for imageable, as compared to nonimageable, nouns. To determine whether such word-class effects vary depending on the stimulus list context in which the words are presented, we varied the proportion of high- and low-image words presented in a…

Previous studies have found that the gaze direction of a centrally presented face facilitates response time (RT) to a lone peripheral target. The widely accepted interpretation of this finding is that gaze direction triggers a cortically mediated reflexive shift of spatial attention. In the present study we tested an alternative explanation, that…

This study investigated gender differences on memory processing using event-related potentials (ERPs). Behavioral data and ERPs were recorded in 16 males and 10 females during a recognition memory task for faces. The behavioral data results showed that females performed better than males. Gender differences on ERPs were evidenced over anterior…

This study was designed to investigate whether the neuropsychological correlates of the symptom dimensions of schizophrenia vary with the clinical state in patients followed from the acute to stable the phase of the illness. Fifteen patients were assessed for symptoms (SAPS-SANS) and undergone a complete neuropsychological assessment at two…

Neuroimaging and lesion studies have provided insights into the neural mechanisms underlying numerical processing, yet the roles of the right and left hemispheres have not been systematically investigated within a single study. To address this issue, we investigated subitizing and magnitude comparison abilities in a split-brain patient. The first…