Gray’s (1970, 1987) reinforcement sensitivity theory is a biologically based personality theory that postulates the existence of three basic behavioural and motivational systems. Differences in sensitivity of these systems translate into individual differences in behaviour. Behavioural inhibition system (BIS) and Behavioural activation system (BAS) are of special importance as individual differences in their sensitivities result in differences in extraversion and neuroticism. This paper presents the results of an empirical validation of the Croatian translation of the BIS/BAS scale (Carver & White, 1994). Exploratory factor analysis preformed on a sample of 286 university students resulted in a solution with four interpretable factors, similar to ones reported by original authors. Sensitivity of the inhibitory system is defined as a single construct, while the sensitivity of the activation system is defined as three independent but correlated constructs. Confirmatory factor analytic approach was used to test four nested models corresponding to four plausible hypotheses about the structure of the instrument. The solution with four correlated factors with one item error covariance introduced showed the best fit. Internal consistency coefficients speak of acceptable reliabilities of Croatian versions of the scales, comparable in size to those obtained on the original sample. Sensitivity of the two behavioural systems explained 26% of variation in extraversion and 78% of variation in neuroticism measures.

reinforcement sensitivity, behavioural activation/inhibition