Table 2.

Quantification of regions of interest MR images.

	Age	Volume (mm3)	Statistics	Significance	Percentage (%)	Statistics	Significance
Whole	Young	218.73 ± 9.9	t(8) = 1.759	p = 0.117
	Old	240.18 ± 7.14
Learning/Memory regions
CTX	Young	71.03 ± 1.96	t(8) = 0.759	p = 0.470	32.51 ± 0.48	t(8) = 3.277	p = 0.011*
	Old	68.63 ± 2.48			28.66 ± 1.06
OB	Young	9.43 ± 0.56	t(7) = 1.378	p = 0.211	4.11 ± 0.21	t(7) = 0.006	p = 0.995
	Old	10.29 ± 0.44			4.32 ± 0.26
HIP	Young	12.37 ± 0.46	t(8) = 3.800	p = 0.005*	5.67 ± 0.26	t(8) = 4.226	p = 0.003*
	Old	10.09 ± 0.38			4.23 ± 0.22
CP	Young	12.09 ± 0.53	t(8) = 0.513	p = 0.622	5.53 ± 0.20	t(8) = 1.137	p = 0.288
	Old	12.45 ± 0.45			5.20 ± 0.21
CB	Young	31.44 ± 1.02	t(7) = 3.556	p = 0.009*	14.06 ± 0.56	t(7) = 3.787	p = 0.007*
	Old	27.07 ± 0.63			11.32 ± 0.41
BLA	Young	2.33 ± 0.32	t(8) = 1.252	p = 0.246	0.32 ± 0.04	t(8) = 2.060	p = 0.073†
	Old	1.92 ± 0.11			0.24 ± 0.01
Circadian visual regions
opt	Young	2.07 ± 0.04	t(4) = 5.814	p = 0.004*	0.27 ± 0.01	t(4) = 3.484	p = 0.025*
	Old	3.32 ± 0.16			0.40 ± 0.03
dLGN	Young	2.44 ± 0.12	t(8) = 2.525	p = 0.036*	0.33 ± 0.03	t(8) = 2.975	p = 0.025*
	Old	2.03 ± 0.11			0.25 ± 0.01
vLGN	Young	0.79 ± 0.05	t(8) = 0.161	p = 0.876	0.11 ± 0.01	t(8) = 0.878	p = 0.406
	Old	0.8 ± 0.05			0.10 ± 0.004
EPI	Young	1.05 ± 0.08	t(8) = 1.928	p = 0.090†	0.14 ± 0.02	t(8) = 2.557	p = 0.034*
	Old	0.83 ± 0.08			0.10 ± 0.01
SC	Young	4.63 ± 0.11	t(8) = 1.644	p = 0.139	0.63 ± 0.02	t(8) = 3.072	p = 0.015*
	Old	4.12 ± 0.28			0.51 ± 0.03

CTX cortex, OB olfactory bulb, HIP hippocampus, CP caudate nucleus, CB cerebellum, BLA basolateral amygdala, opt optic tract, dLGN dorsal lateral geniculate nucleus, vLGN ventral lateral geniculate nucleus, EPI habenula, SC superior colliculus.

*Bolded and statistical significance at p < 0.05.

^†Trend toward significance p < 0.10.