Cognitive and metacognitive activity in mathematical problem solving: prefrontal and parietal patterns

Students were taught an algorithm for solving a new class of mathematical problems. Occasionally in the sequence of problems, they encountered exception problems that required that they extend the algorithm. Regular and exception problems were associated with different patterns of brain activation. Some regions showed a Cognitive pattern of being active only until the problem was solved and no difference between regular or exception problems. Other regions showed a Metacognitive pattern of greater activity for exception problems and activity that extended into the post-solution period, particularly when an error was made. The Cognitive regions included some of parietal and prefrontal regions associated with the triple-code theory of (Dehaene, S., Piazza, M., Pinel, P., & Cohen, L. (2003). Three parietal circuits for number processing. Cognitive Neuropsychology, 20, 487–506) and associated with algebra equation solving in the ACT-R theory (Anderson, J. R. (2005). Human symbol manipulation within an 911 integrated cognitive architecture. Cognitive science, 29, 313–342. Metacognitive regions included the superior prefrontal gyrus, the angular gyrus of the triple-code theory, and frontopolar regions.     

Expectation and temperament moderate amygdala and dorsal anterior cingulate cortex responses to fear faces

A chronic tendency to avoid novelty is often the result of a temperamental bias called inhibited temperament, and is associated with increased risk for anxiety disorders. Neuroimaging studies have demonstrated that an inhibited temperament is associated with increased amygdalar blood-oxygenation-level-dependent (BOLD) response to unfamiliar faces that were not expected; however, the effects of variations in expectancy remain unknown. Using functional magnetic resonance imaging (fMRI), we studied BOLD response to infrequently encountered fear faces that were either expected or not expected in 42 adults with an inhibited or an uninhibited temperament. Individuals with an inhibited temperament had greater amygdala, but less dorsal anterior cingulate cortex (dACC), BOLD response when the stimuli were expected. In contrast, those with an uninhibited temperament had a smaller amygdala but larger dorsal anterior cingulate cortex BOLD response when expecting to see fear faces. These findings demonstrate temperament differences in expectancy effects and provide preliminary evidence for the dACC as a neural substrate mediating differences in inhibited temperament. Enhanced amygdala sensitivity coupled with weak inhibitory control from the dACC may form a neural circuit mediating behaviors characteristic of inhibited temperament and risk for anxiety disorders.     

Leveraging Motivational Mindsets to Foster Positive Interracial Interactions

As the United States becomes increasingly diverse, interracial contact will become considerably less rare. Much research has suggested that interracial interactions are often stressful and uncomfortable for both Whites and racial minorities. Bringing together several bodies of research, the present article outlines a motivational perspective on the dynamics of intergroup contact. To this end, we consider the roles of three motivational mindsets that have the potential to shape interactions to be less cognitively depleting and more enjoyable for both interactants. In particular, we consider the effects of (i) approach and avoidance motivation (Handbook of Motivation and Cognition: Foundation of Social Behavior, 1990, New York: Guilford Press), (ii) promotion and prevention regulatory focus (American Psychologist, 52 , 1997, 1280), and (iii) learning and performance goals (Psychological Review, 95 , 1988, 256) in shaping the dynamics of interracial contact. We suggest that investigations into these motivational mindsets will offer further insight into how and why interracial interactions go awry and will assist in the development of strategies and interventions that facilitate more smooth and enjoyable contact experiences.     

Brain rCBF and performance in visual imagery tasks: Common and distinct processes

The present study was designed to discover whether variations in normalised regional cerebral blood flow (rCBF) in different brain areas predict variations in performance of different imagery tasks. Positron emission tomography (PET) was used to assess brain activity as 16 participants performed four imagery tasks. These tasks were designed so that performance was particularly sensitive to the participant's ability to form images with high resolution, to generate images from distinct segments, to parse imaged forms into parts while inspecting them, or to transform (rotate) images. Response times and error rates were recorded. Multiple regression analyses revealed that variations in most brain areas predicted variations in performance of only one task, thus demonstrating that the four tasks tap largely independent imagery processes. However, we also found that some underlying processes were recruited by more than one task, particularly those implemented in the occipito‐parietal sulcus, the medial frontal cortex, and Area 18.     

Evaluating the endophenotype model of ADHD neuropsychological deficit: results for parents and siblings of children with ADHD combined and inattentive subtypes

Neurogenetic models predict neuropsychological weaknesses in the relatives of children with attention-deficit/ hyperactivity disorder (ADHD). The authors examined executive and regulatory measures in 386 relatives (307 parents, 79 siblings) of children with ADHD combined type, ADHD inattentive type, and controls. Predicted deficits were seen on trailmaking (relatives of ADHD combined type only), stop-signal reaction times (relatives of girls only), and response variability (mothers only) but not on naming or output speed. Effects generally held, even with relatives' ADHD status controlled. A neuropsychologically impaired subgroup of children with ADHD had relatives with clear neuropsychological weaknesses. The authors conclude that a neurogenetic model of ADHD etiology is supportable only for a subset of executive functions and that neuropsychological heterogeneity warrants more examination in ADHD.     

Cumulative risk disparities in children's neurocognitive functioning: a developmental cascade model

The current longitudinal study examined the role of cumulative social risk on children's theory of mind (ToM) and executive functioning (EF) across early development. Further, we also tested a cascade model of development in which children's social cognition at 18 months was hypothesized to predict ToM and EF at age 4.5 through intermediary language skills at age 3. We then examined whether this developmental mechanism varied as a function of social risk status. Participants were 501 children recruited when they were newborns, at which point eight psychosocial risk factors were assessed and combined into a metric of cumulative social disadvantage. Families were followed up at 18 months, at which point four social‐cognitive skills were assessed using developmentally sensitive tasks: joint attention, empathy, cooperation, and self‐recognition. Language was measured at age 3 using a standardized measure of receptive vocabulary. At age 3 and 4.5, EF and ToM were measured using previously validated tasks. Results showed that there were notable cumulative risk disparities in overall neurocognitive skill development, and these effects became more differentiated over time. Support was also found for a developmental mechanism wherein the effect of social cognition at 18 months on ToM and EF in the preschool period operated specifically through children's receptive language ability at age 3. This pathway functioned similarly for children with both low‐ and high‐risk backgrounds. These results extend previous findings by documenting the role of cumulative social disadvantage on children's neurocognition and the pathways that link key neurocognitive abilities across early development.