The road not taken: creative solutions require avoidance of high-frequency responses

To investigate individual differences in creativity as measured with a complex problem-solving task, we developed a computational model of the remote associates test (RAT). For 50 years, the RAT has been used to measure creativity. Each RAT question presents three cue words that are linked by a fourth word, which is the correct answer. We hypothesized that individuals perform poorly on the RAT when they are biased to consider high-frequency candidate answers. To assess this hypothesis, we tested individuals with 48 RAT questions and required speeded responding to encourage guessing. Results supported our hypothesis. We generated a norm-based model of the RAT using a high-dimensional semantic space, and this model accurately identified correct answers. A frequency-biased model that included different levels of bias for high-frequency candidate answers explained variance for both correct and incorrect responses. Providing new insight into the nature of creativity, the model explains why some RAT questions are more difficult than others, and why some people perform better than others on the RAT.     

Childhood-onset multiple sclerosis and mood disorders: a case study.

Multiple Sclerosis (MS) is rare in children. Little research exists regarding emotional and behavioral disorders in childhood-onset MS, despite the occurrence of such problems in adults with MS. This paper describes the cognitive and behavioral characteristics of a boy diagnosed with MS at age 9 and mood disorder at age 10. He displayed no cognitive or behavioral problems prior to the onset of physical symptoms of MS. Three years after diagnosis, this child showed persistent problems with speed of processing, visual-motor skills, and parent and teacher-reported executive functioning. In addition, he had difficulties with emotional lability, behavioral disinhibition, depression, and social interaction. As with adults, children with MS may be at increased risk for mood disorder compared to their peers. Mood disorders in children with MS are likely to be multiply determined, although the specific causal mechanisms are unknown.     

Childhood-Onset Multiple Sclerosis and Mood Disorders: A Case Study

Multiple Sclerosis (MS) is rare in children. Little research exists regarding emotional and behavioral disorders in childhood-onset MS, despite the occurrence of such problems in adults with MS. This paper describes the cognitive and behavioral characteristics of a boy diagnosed with MS at age 9 and mood disorder at age 10. He displayed no cognitive or behavioral problems prior to the onset of physical symptoms of MS. Three years after diagnosis, this child showed persistent problems with speed of processing, visual-motor skills, and parent and teacher-reported executive functioning. In addition, he had difficulties with emotional lability, behavioral disinhibition, depression, and social interaction. As with adults, children with MS may be at increased risk for mood disorder compared to their peers. Mood disorders in children with MS are likely to be multiply determined, although the specific causal mechanisms are unknown.     

Mapping gray matter development: Implications for typical development and vulnerability to psychopathology

Recent studies with brain magnetic resonance imaging (MRI) have scanned large numbers of children and adolescents repeatedly over time, as their brains develop, tracking volumetric changes in gray and white matter in remarkable detail. Focusing on gray matter changes specifically, here we explain how earlier studies using lobar volumes of specific anatomical regions showed how different lobes of the brain matured at different rates. With the advent of more sophisticated brain mapping methods, it became possible to chart the dynamic trajectory of cortical maturation using detailed 3D and 4D (dynamic) models, showing spreading waves of changes evolving through the cortex. This led to a variety of time-lapse films revealing characteristic deviations from normal development in schizophrenia, bipolar illness, and even in siblings at genetic risk for these disorders. We describe how these methods have helped clarify how cortical development relates to cognitive performance, functional recovery or decline in illness, and ongoing myelination processes. These time-lapse maps have also been used to study effects of genotype and medication on cortical maturation, presenting a powerful framework to study factors that influence the developing brain.