TABLE 3.

Differences of fractional amplitude of low-frequency fluctuation (fALFF) values in three frequency bands among the groups.

Contrast	Brain regions	BA	Volume (mm3)	MNI coordinates			t-value
				X	Y	Z
1. Conventional frequency band
PD-A vs. HCs	PD-A < HCs
	left Cerebelum_6	37	1755	−30	−60	−27	−4.4
	right inferior frontal gyrus, orbital part	47	2133	51	36	−6	−4.9
	right superior frontal gyrus, medial	8	2457	3	36	42	−5.0
	left supplementary motor area	32	2457	−3	15	45	−5.7
	PD-A > HCs
	left middle occipital gyrus	18	3483	−33	−84	12	4.7
PD-A vs. PD-NA	PD-A < PD-NA
	right middle frontal gyrus	46	1296	45	48	3	−4.8
PD-NA vs. HCs	NA
2. Slow-4 band
	PD-A < HCs
	right middle frontal gyrus	46	1512	45	54	6	−4.1
	PD-A > HCs
	left cuneus	18	1458	0	−81	30	4.2
PD-A vs. PD-NA	NA
PD-NA vs. HCs	NA
3. Slow-5 band
PD-A vs. HCs	PD-A < HCs
	right insula		2754	51	12	−6	−4.7
	left insula	48	2349	−45	12	−3	−5.1
	left anterior cingulate gyri	10	1647	0	42	−3	−3.4
	left superior frontal gyrus, medial	32	2106	0	45	30	−4.1
	left supplementary motor area	32	2052	−3	12	48	−5.0
	PD-A > HCs
	left superior temporal gyrus	22	1701	−60	−45	15	4.5
	left middle occipital gyrus	19	3618	−33	−81	27	5.7
PD-A vs. PD-NA	NA
PD-NA vs. HCs	PD-NA < HCs
	right Cerebelum_9		1350	3	−51	−45	−4.9

BA, Brodmann’s area; MNI, Montreal Neurological Institute; PD-A, Parkinson’s disease with apathy; PD-NA, Parkinson’s disease without apathy; HCs, healthy controls; NA, Not applicable; - no significant clusters detected.