The functional and structural characteristics of the emotion network in alexithymia

Figures & data

Table 1 The MNI coordinates of the selected ROIs in the emotion network

Name	X	Y	Z	Radius (mm)
Visual area 8/bilateral superior cerebellum (V8/sCB, Bi)	−11	−62	−20	12
Bilateral middle temporal complex (MT+, Bi)	−28	−69	9	12
Right visual area 4 (V4, R)	44	−79	−4	12
Right lateral occipital cortex/temporal lobe (latOCC/Temp, R)	49	−56	−2	12
PCC	1	−54	25	12
Primary visual cortex (V1)	−7	−89	0	12
Dorsal medial prefrontal cortex (dmPFC)	−2	51	29	12
Pregenual anterior cingulate cortex (pgACC)	1	39	2	12
Rostral dorsal anterior cingulate cortex (rdACC)	0	29	25	12
Ventral anterior insula/frontal operculum/right temporal pole, bilateral posterior	38	19	−11	12
Orbitofrontal cortex (vaIns/frOP/TP, RpOFC, Bi)
Anterior insula, posterior orbitofrontal cortex (aIns, pOFC, Bi),	−40	23	−6	12
Bilateral ventral anterior insula/temporal cortex/orbitofrontal cortex (vaIns/TC/OFC, Bi)	−7	12	−23	12
Bilateral middle insula, right dorsal putamen (midIns, Bi dPut, R)	21	0	2	12
Left ventral Striatum, middle insula, hippocampus (vStr, midIns, HCMP, L)	−36	0	−8	12
Left Basolateral Amygdala (Amy_L)	−23	−3	−21	12
Hypothalamus (Hy)	−7	−5	−13	12
Periaqueductal gray/thalamus (PAG/Thal)	−1	−23	2	12
Bilateral amygdala, ventral striatum, ventral globus pallidus, thalamus (Amy vStr vGP Thal, Bi)	11	−6	−10	12
Right frontal operculum (frOP, R)	46	24	6	12
Right inferior frontal gyrus (IFG, R)	49	20	19	12
Left pre-supplementary motor area, inferior frontal gyrus (preSMA, IFG, L)	−23	13	37	12

Abbreviations: MNI, Montreal Neurological Institute; PCC, posterior cingulate cortex; ROI, region of interest.

Table 2 Comparison of the demographic variables and psychological measurements between the Alex and the HC groups

Variables	Alex group, n=21	HC group, n=21	p-value
Demographic data
Males, n (%)	11 (52.4)	11 (52.4)
Age (years)	18.33 (1.06)	18.62 (1.07)	p=0.39
TAS-20 scores*	58.10 (3.2)	41.00 (7.75)	p<0.001

Notes: Data are presented as percentage/ratio or mean ± SD;

* p<0.05.

Abbreviations: Alex, alexithymia; HC, healthy control; TAS-20, Toronto Alexithymia Scale-20.

Figure 1 Brain regions in the emotion network showing significant differences on ALFF between the Alex and the HC groups.

Notes: Red balls indicate Alex group > HC group; blue balls indicate Alex group < HC group; gray balls represent other brain regions in the emotion network.
Abbreviations: Alex, alexithymia; aIns, pOFC, anterior insula, posterior orbitofrontal cortex; ALFF, amplitude of low-frequency fluctuation; Amy vStr vGP Thal, Bi, bilateral amygdala, ventral striatum, ventral globus pallidus, thalamus; Amy_L, left basolateral amygdala; dmPFC, dorsal medial prefrontal cortex; frOP, R, right frontal operculum; HC, healthy control; Hy, hypothalamus; IFG, R, right inferior frontal gyrus; latOCC/Temp, R, right lateral occipital cortex/temporal lobe; midIns, Bi dPut, R, bilateral middle insula, right dorsal putamen; MT+, Bi, bilateral middle temporal complex; PAG/thal, periaqueductal gray/thalamus; pgACC, pregenual anterior cingulate cortex; preSMA, IFG, L, left pre-supplementary motor area, inferior frontal gyrus; rdACC, rostral dorsal anterior cingulate cortex; V4, R, right visual area 4; V8/sCB, Bi, visual area 8/bilateral superior cerebellum; vaIns/frOP/TP, RpOFC, Bi, ventral anterior insula/frontal operculum/right temporal pole, bilateral posterior orbitofrontal cortex; vaIns/TC/OFC, Bi, bilateral ventral anterior insula/temporal cortex/orbitofrontal cortex; vStr, midIns, HCMP, L, left ventral striatum, middle insula, hippocampus.

Table 3 Brain regions in the emotion network showing significant differences on ALFF between the Alex and the HC groups

	ALFF value		t-value	p-value
	Alex group	HC group
V8/sCB, Bi	0.996 ± 0.015	0.991 ± 0.021	0.832	0.410
MT+, Bi	1.001 ± 0.016	1.000 ± 0.040	0.025	0.980
V4, R	0.886 ± 0.014	0.893 ± 0.012	−1.574	0.123
latOCC/Temp, R	0.992 ± 0.017	0.997 ± 0.029	−0.703	0.486
PCC	1.003 ± 0.017	0.993 ± 0.033	1.189	0.242
V1*	1.001 ± 0.019	1.019 ± 0.028	−2.477	0.018
dmPFC	1.004 ± 0.019	0.999 ± 0.022	0.744	0.461
pgACC	0.993 ± 0.027	0.995 ± 0.031	−0.254	0.801
rdACC*	1.002 ± 0.022	0.984 ± 0.022	2.587	0.013
vaIns/frOP/TP, RpOFC, Bi	0.998 ± 0.010	0.989 ± 0.019	1.784	0.082
aIns, pOFC, Bi,	0.998 ± 0.015	0.997 ± 0.022	0.125	0.901
vaIns/TC/OFC, Bi	0.990 ± 0.015	0.994 ± 0.021	−0.769	0.446
midIns, Bi dPut, R	0.993 ± 0.024	0.993 ± 0.023	0.073	0.942
vStr, midIns, HCMP, L	0.995 ± 0.012	1.001 ± 0.021	−1.048	0.301
Amy_L*	0.989 ± 0.019	1.002 ± 0.023	−2.141	0.038
Hy	0.990 ± 0.020	0.999 ± 0.019	−1.498	0.142
PAG/Thal	0.993 ± 0.023	1.001 ± 0.017	−1.321	0.194
Amy vStr vGP Thal, Bi	0.995 ± 0.015	1.000 ± 0.014	−1.065	0.293
frOP, R	1.004 ± 0.014	0.993 ± 0.026	1.702	0.097
IFG, R	1.004 ± 0.011	0.996 ± 0.021	1.451	0.155
preSMA, IFG, L	1.004 ± 0.012	1.004 ± 0.010	0.000	1.000

Notes: Data are presented as percentage/ratio or mean ± SD;

* p<0.05.

Abbreviations: Alex, alexithymia; aIns, pOFC, anterior insula, posterior orbitofrontal cortex; ALFF, amplitude of low-frequency fluctuation; Amy vStr vGP Thal, Bi, Bilateral amygdala, ventral striatum, ventral globus pallidus, thalamus; Amy_L, Left basolateral amygdala; dmPFC, dorsal medial prefrontal cortex; frOP, R, right frontal operculum; HC, healthy control; Hy, hypothalamus; IFG, R, right inferior frontal gyrus; latOCC/Temp, R, right lateral occipital cortex/temporal lobe; midIns, Bi dPut, R, Bilateral middle insula, right dorsal putamen; MT+, Bi, bilateral middle temporal complex; PAG/thal, periaqueductal gray/thalamus; PCC, posterior cingulate cortex; pgACC, pregenual anterior cingulate cortex; preSMA, IFG, L, left pre-supplementary motor area, inferior frontal gyrus; rdACC, rostral dorsal anterior cingulate cortex; V4, R, right visual area 4; V8/ sCB, Bi, visual area 8/bilateral superior cerebellum; vaIns/frOP/TP, RpOFC, Bi, ventral anterior insula/frontal operculum/right temporal pole, bilateral posterior orbitofrontal cortex; vaIns/TC/OFC, Bi, bilateral ventral anterior insula/temporal cortex/orbitofrontal cortex; vStr, midIns, HCMP, L, left ventral striatum, middle insula, hippocampus.

Table 4 Comparison analysis of gray matter on GM density between the Alex and the HC groups

	GM density value		t-value	p-value
	Alex group	HC group
V8/sCB, Bi	0.718 ± 0.045	0.734 ± 0.033	−1.345	0.186
MT+, Bi	0.2298 ± 0.027	0.235 ± 0.029	−0.602	0.551
V4, R	0.378 ± 0.039	0.358 ± 0.047	1.449	0.155
latOCC/Temp, R	0.438 ± 0.076	0.446 ± 0.048	−0.429	0.670
PCC	0.651 ± 0.055	0.668 ± 0.043	−1.107	0.275
V1	0.601 ± 0.044	0.721 ± 0.033	0.991	0.328
dmPFC	0.529 ± 0.048	0.529 ± 0.039	−0.028	0.978
pgACC	0.546 ± 0.077	0.547 ± 0.068	−0.072	0.943
rdACC	0.560 ± 0.095	0.574 ± 0.064	−0.542	0.591
vaIns/frOP/TP, RpOFC, Bi	0.557 ± 0.078	0.571 ± 0.046	−0.735	0.467
aIns, pOFC, Bi,	0.540 ± 0.051	0.528 ± 0.046	0.805	0.426
vaIns/TC/OFC, Bi	0.431 ± 0.025	0.429 ± 0.035	0.238	0.813
midIns, Bi dPut, R	0.426 ± 0.047	0.431 ± 0.032	−0.415	0.681
vStr, midIns, HCMP, L	0.655 ± 0.039	0.654 ± 0.042	0.103	0.919
Amy_L	0.700 ± 0.027	0.706 ± 0.028	−0.663	0.511
Hy	0.408 ± 0.025	0.406 ± 0.028	0.299	0.767
PAG/Thal	0.517 ± 0.048	0.503 ± 0.043	1.015	0.316
Amy vStr vGP Thal, Bi	0.348 ± 0.021	0.345 ± 0.027	0.499	0.621
frOP, R	0.422 ± 0.087	0.439 ± 0.044	−0.809	0.423
IFG, R	0.409 ± 0.075	0.426 ± 0.036	−0.946	0.350
preSMA, IFG, L	0.183 ± 0.035	0.182 ± 0.028	0.143	0.887

Notes: Data are presented as percentage/ratio or mean ± SD; there are some significant differences, p<0.05.

Abbreviations: Alex, alexithymia; aIns, pOFC, anterior insula, posterior orbitofrontal cortex; Amy vStr vGP Thal, Bi, Bilateral amygdala, ventral striatum, ventral globus pallidus, thalamus; Amy_L, left basolateral amygdala; dmPFC, dorsal medial prefrontal cortex; frOP, R, right frontal operculum; GM, gray matter; HC, healthy control; Hy, hypothalamus; IFG, R, right inferior frontal gyrus; latOCC/Temp, R, right lateral occipital cortex/temporal lobe; midIns, Bi dPut, R, Bilateral middle insula, right dorsal putamen; MT+, Bi, bilateral middle temporal complex; PAG/thal, periaqueductal gray/thalamus; pgACC, pregenual anterior cingulate cortex; preSMA, IFG, L, left pre-supplementary motor area, inferior frontal gyrus; rdACC, rostral dorsal anterior cingulate cortex; V4, R, right visual area 4; V8/sCB, Bi, visual area 8/bilateral superior cerebellum; vaIns/ frOP/TP, RpOFC, Bi, ventral anterior insula/frontal operculum/right temporal pole, bilateral posterior orbitofrontal cortex; vaIns/TC/OFC, Bi, bilateral ventral anterior insula/ temporal cortex/orbitofrontal cortex; vStr, midIns, HCMP, L, left ventral striatum, middle insula, hippocampus.

Figure 2 The functional connectivity showing significant differences between the Alex and the HC groups.

Notes: Red balls indicate Alex group > HC group; blue balls indicate Alex group < HC group and the brain regions with weak functional connectivity; gray balls represent other brain regions in the emotion network. Blue lines indicate weak functional connectivity in Alex group, compared with HC group.
Abbreviations: Alex, alexithymia; dmPFC, dorsal medial prefrontal cortex; frOP, aIns, anterior insula, frontal operculum; HC, healthy control; Hy, hypothalamus; IFG, inferior frontal gyrus; latOCC, lateral occipital cortex; MT+, middle temporal complex; PAG, periaqueductal gray; PCC, posterior cingulate cortex; PARA, paracentral lobule; pgACC, pregenual anterior cingulate cortex; pOFC, anterior insula, posterior orbitofrontal cortex; preSMA, L, left pre-supplementary motor area; STG, superior temporal gyrus; V8/sCB, visual area 8/ superior cerebellum; vaIns, ventral anterior insula; vGP, ventral globus pallidus; vStr, ventral striatum.

Table 5 Comparison of the functional and structural connectivity between the Alex and the HC groups

	FC/FA value		t-value	p-value
	HC group	Alex group
Functional connectivity (FC value)
V1 and Temporal_Sup_L (MNI: −57, −12, 15)*	0.12 ± 0.041	0.024 ± 0.011	−4.0639	0.002
V1 and Paracentral_Lobule_L (MNI: −6, −18, 72)*	0.427 ± 0.075	0.337 ± 0.065	−4.140	0.001
Amy_L and Temporal_Sup_L (MNI: −57, −12, 15)*	0.314 ± 0.047	0.283 ± 0.044	−3.9274	0.003
Amy_L and SMA (MNI: 12, −9, 51)*	0.105 ± 0.035	0.038 ± 0.016	−4.771	<0.001
Structural connectivity (FA value)
V1 and Temporal_Sup_L	0.476 ± 0.115	0.411 ± 0.174	1.422	0.163
V1 and Paracentral_Lobule_L	0.328 ± 0.214	0.280 ± 0.226	0.707	0.484
Amy_L and Temporal_Sup_L	0.315 ± 0.255	0.275 ± 0.245	0.507	0.615
Amy_L and SMA	0.390 ± 0.196	0.294 ± 0.237	1.439	0.158

Notes: Data are presented as percentage/ratio or mean ± SD;

* p<0.05.

Abbreviations: Alex, alexithymia; Amy_L, left basolateral amygdala; HC, healthy control; MNI, Montreal Neurological Institute; Paracentral_Lobule_L, left paracentral lobule; SMA, supplementary motor area; Temporal_Sup_L, left superior temporal gyrus.