. 2017 Oct 18;119(2):700–722. doi: 10.1152/jn.00630.2017

Table 3.

Correlogram features detected among all 33,422 neuron pairs grouped according to brain stem location and response to carotid chemoreceptor stimulation

			Target Cell Location and Response to Carotid Chemoreceptor Stimulation
			p-NTS-MM								FTL-pF								Raphe-mRF								VRC
			↑		↓		↕		→		↑		↓		↕		→		↑		↓		↕		→		↑		↓		↕		→
Trigger Cell Location and Response		Feature Location	P	T	P	T	P	T	P	T	P	T	P	T	P	T	P	T	P	T	P	T	P	T	P	T	P	T	P	T	P	T	P	T
p-NTS-MM	↑	Offset	^*			^†				1	2^*			2^†	1	1			1^*	1	1	^†			2		1^*	3		^†				1
		Central		1			1		1		5	1								1					2		12	3	1		1		2	1
		Total	148		57		60		259		276		69		22		291		183		37		16		355		*718*		214		70		332
	↓	Offset	1	^‡	1^§	1						^‡	^§				1			^‡	1^§						2	^‡	2^§	2				1
		Central			2							1					1								2			1	1				1
		Total			21		18		95		57		32		4		70		52		12		5		142		280		65		36		126
	↕	Offset		1									1
		Central								1								1									1	1			1
		Total					6		76		42		9		4		59		45		8		7		79		127		28		12		39
	→	Offset		2						1	1										1				1	1	1	3	1	1
		Central							1		3						2		5			1			4		3	1		1			3	2
		Total							255		185		56		36		477		172		44		44		643		614		207		92		610
FTL-pF	↑	Offset	2^*		3	^†			1		3^*	3	3	3^†			1	1	2^*		2	^†			2	1	17^*	9	4	3^†		2	2	2
		Central									6	1	9	10			5		2	1	2	1			4	1	20	14	13	6	7	3	3	1
		Total									142		81		27		269		165		35		9		362		618		215		64		387
	↓	Offset	2	^‡	^§						2	2^‡	1^§	1						^‡	^§						17	7^‡	14^§	4	4	1		2
		Central											3	2			1				1						18	3	4	1	4	2	2
		Total											17		3		55		38		9		5		84		249		93		41		111
	↕	Offset							1
		Central																									1						1
		Total													2		52		6		3		5		65		45		22		7		70
	→	Offset	5	1	3				3	2	2	2		1			6	4	8	1	3	2			12	1	4	2	2	1	1		12	7
		Central															7	1			1				5	3	7		1	2			6
		Total															267		185		64		42		681		615		244		96		818
Raphe-mRF	↑	Offset	1^*			^†			1		^*	1^†						1	1^*	1	1	2^†			4	3	1^*		3	2^†			3	2
		Central																	6		3				18	1	5		1	2	1		6	1
		Total																	143		82		21		629		815		192		77		703
	↓	Offset		^‡	^§	1						^‡	^§				1		1	^‡	^§				2			^‡	^§			1
		Central																							4	1	4	1	2				2
		Total																			6		7		216		225		64		24		235
	↕	Offset
		Central																							1								1	1
		Total																					1		82		60		24		12		86
	→	Offset		1					4			1						1	4	1		1			15	10	8	1	5	2			7	3
		Central																							22	8	14	11	5				19	5
		Total																							1,472		2,015		599		252		2,975
VRC	↑	Offset	14^*	6	2	4^†	2		4	1	6^*	3	4	9^†			7	1	3^*	4	2	3^†			6	5	74^*	74	12	19^†	6	1	19	9
		Central																									121	26	44	26	17	7	35	11
		Total																									1,524		933		349		2,159
	↓	Offset	3	1^‡	^§				1		5	1^‡	4^§	9					6	4^‡	^§	1			2	2	12	17^‡	4^§	6	1	2	1	3
		Central																											9	1	9	3	6	6
		Total																											142		114		719
	↕	Offset	1		1						1	3		6				1		2	1						4	5	1	1		2	3	4
		Central																													1		4	2
		Total																												18		319
	→	Offset	3	3	1	1			2		5	1	2	1			16	4	3	2	1	3			7	3	9	14	5	8	5	1	21	21
		Central																															30	8
		Total																															1,662

Offset (n = 913) and central (n = 768) correlogram features detected among 33,422 neuron pairs grouped according to brain stem location and response to injection of CO₂-saturated saline into the carotid artery (arrows; neurons with no response and those not tested for response are grouped together). Trigger (left) and target (top) neurons are organized so that offset features have positive time lags. Numbers of offset and central peaks (P) and troughs (T) are reported; numbers in italics are the total number of pairs composed of neurons with the locations and stimulus responses indicated by the row and column labels. Central features are reported only in the top right portion of the table because the designation of trigger and target neuron is irrelevant for central feature correlations: the central feature will still be present after switching the 2 spike trains. Similarly, total numbers of specific pairings are found only in the top right portion of the table. For example, a total of 718 cell pairs composed of a p-NTS-MM↑ and a VRC↑ neuron were analyzed (see the 2 boldface cell groups). Correlograms calculated for 24 of these pairs contained an offset feature: 4 were suggestive of a p-NTS-MM↑ → VRC↑ influence (1 peak, 3 troughs) and 20 of a VRC↑ → p-NTS-MM↑ effect (14 peaks, 6 troughs). In addition, 15 central features were detected (12 peaks, 3 troughs) for pairs of this type. Symbols indicate the pair types (and numbers of such pairs) whose offset correlogram feature and neuronal responses are simply interpreted as functional actions that promote changes in target cell activity during response to peripheral chemoreceptor stimulation:

excitation (feature, response of trigger and target cell: peak, ↑↑);

^†

inhibition (trough, ↑↓);

^‡

disinhibition (trough, ↓↑);

^§

disfacilitation (peak, ↓↓).