Suicide and Homicide Rates in Canada and the United States

Suicide and homicide rates by age were analyzed for Canada and the United States, indicating that suicide is higher in Canada and that homicide is higher in the United States. Results indicated a positive association between homicide and suicide rates in the United States but these two rates of death were not significantly associated in Canada. Holinger (1987) had associated the relative size of the cohort to the rates of suicide and homicide in young people in the United States. The more current data in both countries did not support Holinger's results. Using the measure devised by Easterlin (1980) and Ahlburg and Schapiro (1984) –that is, the proportion of youths aged 15–24 relative to adults aged 25–64–the correlation between the size of the youth cohort and the suicide rate of youths aged 15–24 was negative. It is concluded that the two patterns in these two countries may be explained from a historical perspective.     

Adaptation to displacing prisms in human infants.

This research reports a first attempt to study adaptation to laterally displacing prisms in human infants of ages six to ten months. Twenty infants were tested over four days under conditions similar to those used in adult adaptation studies. Evidence was found of vigorous adaptation when infants were exposed to base-right prisms under conditions of active exposure. Detailed consideration is given to the conditions and methods of studying adaptation in infants and implications for adult studies.