Sandra Canter & Gordon Claridge 
Personality Differences and Biological Variations 
A Study of Twins

Personality Differences and Biological Variations: A Study of Twins details a study aimed to discover the genetic uniqueness of twins and the biological basis of their individual differences. Coverage of the book includes the details of the project — its aims, method, its theoretical background, sample selection and the description of the sample; personality traits in twins the sociability/impulsivity and the Foulds hostility scale; and the influence of age and separation. The book also covers some aspects of cognitive function in twins — divergent thinking and the analysis of its measures; conceptual thinking; and the relationship of personality and cognitive function. The book also includes twins’ physiological measures; their sedative drug tolerance; and a nervous typological analysis of their personal variaton. The text is recommended for psychologists who wish to learn more and study about how twins think and how they get along with one another.