Table 1. Hierarchical structure identification according to fuzzy clustering of metal distribution. CB = cerebellum; CP = caudoputamen; cpd = cerebral peduncle; CTX = cerebral cortex; HIP = hippocampal formation; HY = hypothalamus; IPN = interpeduncular nucleus; MOB = main olfactory bulb; MTN = midline groups of the dorsal thalamus; MY = medulla; P = pons; PAL = pallidum; RAmb = midbrain raphe nuclei SNc = substantia nigra pars compacta; SNr = substantia nigra pars reticulata; VENT = ventral part of the dorsal thalamus. n/a = not applicable, background single only. * For the section at bregma +4.27 mm only 4 clusters were discernable.

Bregma ± (mm)	1		2		3		4		5		6
	ARA classification	% image	ARA classification	% image	ARA classification	% image	ARA classification	% image	ARA classification	% image	ARA classification	% image
(A) +4.27 (olfactory bulbs)*	n/a	14	Fiber tracts, MOB	25	MOB	29	MOB	31	—	0	—	0
(B) –1.16 (thalamus)	n/a	6	MTN; PAL	10	VENT	17	CP	19	CTX; HY	22	CTX; HY	26
(C) –3.58 (midbrain)	n/a	0	—	0	RAmb; SNr	3	HIP; fiber tracts; SNc	11	HIP	40	CTX; P	46
(D) –6.36 (cerebellum)	n/a	2	CB	12	CB	15	CB	20	CB	25	Fiber tracts; MY	27