Group housing decreased horizontal and vertical activity and center time, with effects occurring sooner in females. Nicotine s effects depended on housing and sex. For males, nicotine altered indices of arousal and exploration, increasing these variables for group-housed males but decreasing them for individually housed males. For females, nicotine altered possible indices of anxiety, reducing anxiety for group-housed females. In cessation, housing effects continued in females and appeared more robustly in males.
Results indicate that nicotine s chronic effects depend on subjects sex and living environment.