Effect of vehicle use and maintenance patterns of a self-described group of sensitive individuals and nonsensitive individuals to methyl tertiary-butyl ether in gasoline.

The objective of this study was to compare the driving habits and vehicle maintenance patterns of individuals who report symptoms when exposed to methyl tertiary-butyl ether (MTBE) and those who are asymptomatic when exposed to the oxygenate. Participants were healthy volunteers (CON) and self-reported MTBE-sensitive individuals (SRS) who participated in a controlled exposure study of MTBE in gasoline. A questionnaire was developed to gather information about each participant's automobile usage, engine maintenance habits and fueling and driving patterns. Results showed that the individuals who had self-reported heightened sensitivity to the oxygenate drove their vehicles more often and fueled their vehicles more frequently than asymptomatic individuals. In addition, the self-reported symptomatic individuals in this study were shown to be more likely to drive vehicles with some form of body damage and carbureted engines.

The effects of stimulant drugs on curiosity behaviors of hyperactive boys.

The curiosity behaviors of 20 hyperactive boys, both on and off stimulant drugs, and in relation to 20 nonhyperactive boys, were assessed. Comparisons on object, manipulative, conceptual, perceptual, and reactive curiosity tasks indicated that stimulants reduced only the object curiosity task performance of hyperactive boys, although the level tended to remain above that of nonhyperactive boys. Also, hyperactive boys both on and off drugs tended to have lower conceptual curiosity scores than controls. Implications are discussed.