Brain activity following esophageal acid infusion using positron emission tomography

Table 1 Incidence of heartburn symptoms and heartburn scores induced by each infusion

	Heartburn incidence	Mean heartburn scores (range)
pH 7 (first infusion)	5/15	1.4 (0-7)
pH 7 (second infusion)	5/15	1.0 (0-6)
pH 2	7/15	1.9 (0-9)b
pH 1 (first infusion)	10/15	3.2 (0-10)c
pH 1 (second infusion)	12/15a	5.0 (0-10)d

^aP = 0.0253 vs pH 7 (first infusion) and pH 7 (second infusion);

^bP = 0.0269 vs pH 7 (second infusion);

^cP = 0.0464 vs pH 7 (first infusion), P = 0.0253 vs pH 7 (second infusion);

^dP = 0.0040 vs pH 1 (first infusion), P = 0.0075 vs pH 2, P = 0.0041 vs pH 7 (first infusion), P = 0.0071 vs pH 7 (second infusion).

Table 2 Details of brain activated regions by acid infusion (comparison with baseline)

Condition	Region	Side	BA	x	y	z	Z-score	Voxels in cluster
Frist pH 7 - base	Precentral gyrus	Right	4	56	-8	22	4.23	252
	Superior temporal gyrus	Left	42	-64	-12	6	3.80	72
	Anterior cingulate cortex	Left	24	-12	6	34	3.78	34
	Anterior cingulate cortex	Right	24	12	4	28	3.59	17
	Anterior insula	Right		30	-4	20	3.43	15
Second pH 7 - base	Middle frontal gyrus	Right	10	36	44	-4	4.51	79
	Cuneus	Center		0	-104	-2	4.02	45
	Posterior cingulate cortex	Right	23	28	-52	10	3.84	58
	Postcentral gyrus	Right	1,2	44	-20	32	3.57	19
	Anterior cingulate cortex	Right	24	12	4	26	3.49	31
	Inferior frontal gyrus	Left	47	-50	34	-2	3.49	21
	Middle temporal gyrus	Left	21	-64	-4	-22	3.45	18
	Thalamus	Left		-20	-36	4	3.44	41
	Thalamus	Right		18	16	16	3.44	26
	Superior frontal gyrus	Right	10	10	66	24	3.21	10
pH 2 - base	Cerebellum	Left		-2	-72	-20	4.01	59
	Inferior frontal gyrus	Right	45	34	10	20	3.94	40
	Superior temporal gyrus	Left	38	-52	20	-24	3.85	18
	Anterior insula	Right		30	-4	22	3.78	68
	Putamen	Left		-22	-12	10	3.60	35
	Posterior cingulate cortex	Left	31	-26	-62	12	3.36	28
	Anterior cingulate cortex	Right	24	6	32	-2	3.35	15
	Pons	Center		0	-26	-30	3.34	12
	Superior frontal gyrus	Left	10	-20	52	-8	3.34	14
First pH 1 - base	Precentral gyrus	Right	6	68	4	20	3.85	36
	Superior temporal gyrus	Right	38	32	10	-38	3.80	39
	Middle temporal gyrus	Left	21	-44	-30	-10	3.74	24
	Parahippocampal gyrus	Left		-26	-50	6	3.74	46
	Anterior cingulate cortex	Left	24	-12	26	-2	3.67	20
	Middle temporal gyrus	Left	21	-64	-2	-22	3.48	22
Second pH 1 - base	Parahippocampal gyrus	Right		28	-48	2	4.47	129
	Superior temporal gyrus	Left	38	-52	18	-26	4.12	24
	Cerebellum	Left		-20	-40	-50	4.09	58
	Posterior cingulate cortex	Left	23	-8	-20	26	3.93	15
	Caudate nucleus	Left		-14	-26	20	3.70	32
	Anterior insula	Right		36	12	-14	3.63	27
	Pons	Right		12	-42	-32	3.43	57
	Caudate nucleus	Left		-24	-38	12	3.24	16

Table 3 Summary of brain activated regions by each infusion (comparison with baseline)

Major brain region	Subregion	BA	First pH 7	Second pH 7	pH 2	First pH 1	Second pH 1
Frontal lobe	Superior frontal gyrus	10		R	L
	Middle frontal gyrus	10		R
	Inferior frontal gyrus	47		L
Temporal lobe	Superior temporal gyrus	38			L	R	L
	Superior temporal gyrus	42	L
	Middle temporal gyrus	21		L		L
	Middle temporal gyrus	42	L		L
	Inferior temporal gyrus	45			R
PMA	Precentral gyrus	4	R
	Precentral gyrus	6				R
PSA	Postcentral gyrus	1,2,3		R
ACC	Anterior part	24			R	L + R
	Mid/posterior part	24’	L + R	R
PCC				R	L		L
Insula	Anterior part		R		R		R
Cerebellum					C + L		L
Thalamus				R + L			R + L
PHG						L	R

PMA: Primary motor area; PSA: Primary somatosensory area; ACC: Anterior cingulate cortex; PCC: Posterior cingulate cortex; PHG: Parahippocampal gyrus; BA: Brodmann area; R: Right; L: Left; C: Center.

Table 4 Results of subtraction analysis of brain images after the first and second infusions at pH 1 and 7

Condition	Region	Side	Brodmann area	x	y	z	Z-score	Voxels in cluster
Second pH 1 - first	Orbitofrontal cortex	Right		38	36	-24	4.44	167
	Cuneus	Right	19	2	-82	36	3.79	51
	Cerebellum	Left		-22	-40	-50	3.74	23
	Superior temporal gyrus	Right	8	26	36	40	3.69	37
	Middle frontal gyrus	Right	32	22	50	8	3.69	23
	Pons	Right		10	-36	-12	3.47	31
	Lingual gyrus	Right	19	4	-60	-2	3.37	12
	Putamen	Left		-24	-8	2	3.32	16
	Caudate nucleus	Right		18	-34	16	3.30	16
Second pH 7 - first	Middle frontal gyrus	Right	10	36	46	0	4.03	47
	Cerebellum	Left		-18	-98	-18	3.98	40
	Midbrain	Right		2	-40	2	3.65	27
	Posterior cingulate cortex	Left	23	-14	-16	30	3.61	11
	Superior frontal gyrus	Right	8	14	22	42	3.57	33