Do I need to buy a replacement penny? The Battelle Developmental Inventory 2nd Edition reviewed
February 17, 2012
In his new blog Mental Matrix, Joseph Claeys reviews the Battelle Developmental Inventory 2nd Edition.
Can’t Decide Which IQ Is Best? Make a Composite IQ Score
January 13, 2012
A short tutorial on creating composite scores. It is easier to read if viewed in full screen mode.
Here is a spreadsheet tool that can calculate composite scores.
Table 1 from this article has a nice summary of phenotypical deficits in people with dysgraphia, dyslexia, and oral and written language disorders:
Dysgraphia
Automatic legible letter writing
Orthographic coding
Finger succession
Dyslexia
Pseudoword reading
Spelling
Phonological coding
Orthographic coding
Rapid automatic naming
Inhibition
Rapid automatic switching
Oral and Written Language Learning Disability
Morphological coding
Syntax coding
Conspiracy Theories and Crystallized IQ
July 25, 2011
Agents of the Clandestine World Government posing as researchers have just published this bit of misinformation: People who know what’s really going on know very little! That’s right. This so-called “study” claims that people who believe in “conspiracy theories” (i.e., the truth) have lower crystallized intelligence. Very clever, Clandestine World Government, but we will not be mocked!
Living in a moldy house is bad for your baby’s brain.
July 25, 2011
Check out this prospective cohort study from Poland on the effects of living in a mold-contaminated house on children’s IQ.
This meta-analysis of adolescents and young adults given IQ tests multiple times, the risk of schizophrenia increases about 55% for each standard deviation in IQ lost. This finding should be framed appropriately, however. The risk of schizophrenia is low and remains low, even when IQ drops. Most people in whom IQ drops do not go on to develop schizophrenia. However, the risk of developing schizophrenia is higher among people whose IQ drops significantly.
Good News for Soccer Players? A little bit of heading perhaps not so bad for your head.
July 25, 2011
This experiment assigned participants to one of three treatment conditions: 1) Heading training 2)Soccer training without heading 3) No treatment control. Neuropsychological tests of attention and working memory failed to show any short-term negative effects of heading training (other than more headaches in female participants). Interpretation of this study should be interpreted cautiously: There may be long-term effects of heading that the study was not designed to measure.
The Correlation between Simple and Complex Memory Span Tests Increases with Age in Children and Adolescents
July 23, 2011
This meta-analysis found that simple memory span measures (e.g., Digits Forward) and complex span measures correlate more strongly in adolescents than in children. Eyeballing Figure 1 in the paper, it appears that the correlation increases from about 0.35 at age 5 to about 0.45 at age 20. It does not appear that the finding is an artifact of reliability. The interpretation of the finding is that both types of tests require storage ability and executive ability but in differing proportions. The author of the paper proposes that the executive control of attention in children develops considerably throughout childhood and adolescence whereas the storage capacity of primary memory stays comparatively more stable over time. Thus, performance on simple memory span increases over time mostly as a function of the maturation of executive ability. Thus, simple span measures correlate more strongly with complex span measures (which measure executive control of attention more directly) in older samples than in younger samples.
This longitudinal study of older adults suggests that cognitive declines in late adulthood were steeper for earlier-born cohorts (born 1886-1913) than for later-born cohorts (born 1914-1946).
Here is a new video tutorial that explores the issue of when large differences in subtest scores within a composite tell us to ignore the composite score (Short answer: Not very often).
Here are two images from the video:
