Table 1.

Freezing responses of observers and target mice 24-h post-conditioning as a function of housing condition and sex.

Housing-type	Conditioning-type	Sex	% freezing
isolate	direct	M	67.9±2.23
social	direct	M	63.9±3.40
isolate	direct	F	53.0±2.88
social	direct	F	70.0±2.49***
isolate	vicarious	M	7.8±1.74
social	vicarious	M	11.5±1.33
isolate	vicarious	F	6.2±1.16
social	vicarious	F	18.8±2.26***

Freezing responses of directly and vicariously conditioned B6 mice are displayed relative to their housing context and sex. Data are presented as the mean ± std. error. Asterisks represent significant orthogonal contrasts comparing isolate versus social housing contexts-by-sex for each type of conditioning.

^***P<0.001.