Anxiety-like behaviour is lower in after hours mice.

<p>In the open field test (A-D) <i>Afh</i>/<i>Afh</i> mice entered the central zone more frequently and spent more time there but did not differ in activity measures of speed and distance in the outer zone. In the light-dark box (E–H) <i>Afh</i>/<i>Afh</i> mice entered the light compartment more often and spent more time there and had increased speed in the dark compartment but did not differ in distance travelled in the dark compartment. In the elevated plus maze (I-L), <i>Afh</i>/<i>Afh</i> mice spent more time in the open arms but did not differ in their frequency of entry or closed arm activity measures. (Data shown is mean ± SEM). **<i>P</i><0.01, *<i>P</i><0.05, ^#<i>P</i> = 0.06; effects of genotype in posthoc t-tests (<i>Afh</i>/<i>Afh vs. Afh</i>/+ and +/+<i>)</i>.