consists of measures pertaining to locomotor activity in a novel environment. Factor 6 contains measures pertaining to conflict avoidance. Factor 7, like Factor 3, consists of measures with high factor loadings pertaining to morphine activity, but instead of response these measures are related to duration of activity. Factor 8 consists of measures related to cocaine sensitization. Factor 9 consists of measures related to stress and anxiety such as mechanical sensitivity (von Frey threshold) and zero-maze measures and adrenal weights. Factor 10 consists of measures related to vertical activity spanning general behavior and cocaine test batteries. Factor 11 represents measures related to startle response. Factor 12 consists of measures pertaining to drug environment conditioning. Factors 13 and 14 both consist of responsivity measures, with Factor 13 describing response to sensitivity, whereas Factor 14 describes response to novelty. Lastly, Factor 15 represents anxiety related to acute stress. Factor scores from individual strains can be plotted on a set of axes representing each factor, showing a behavioral profile of each strain (Fig. 4).
