Benjamin L Brett

  • Citations Per Year
Learn More
Isofemale lines of Pseudococcus affinis (Maskell ) differ in their ability to maintain B chromosomes (Bs) due to the presence of genotypes that affect the rate of transmission (k) of the Bs. The nature of these genotypes was analyzed by comparing ks of males carrying the same B and the same paternal genome (which is heterochromatic), but differing in their(More)
The rate of transmission (k) of a supernumerary B chromosome in male mealybugs is shown to depend strongly on the chromosome set of maternal origin. When both parents came from an isofemale line in which the frequency of the B chromosome increased rapidly and stabilized at a mean of more than 4.0 B chromosomes per individual, k was 0.92 and 0.95 in two(More)
Objective This study examined the test-retest reliability of the four- and two-factor structures (i.e., Memory and Speed) of ImPACT over a 2-year interval across multiple groups with premorbid conditions, including those with a history of special education or learning disorders (LD; n = 114), treatment history for headache/migraine (n = 81), and a control(More)
OBJECTIVE Research findings to date on the stability of Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) Composite scores have been inconsistent, requiring further investigation. The use of test validity criteria across these studies also has been inconsistent. Using multiple measures of stability, we examined test-retest reliability of(More)
Investigating short-term effects of subconcussive impacts on neurocognitive functioning, we employed a repeated measures multivariate model and regression-based measure to examine neurocognitive changes in 771 contact and noncontact high school athletes over a two-year period. Results reveal significant changes in Visual Motor Speed for both groups over a(More)
  • 1