Table 3.

Effect of Maturation on Pharyngeal and Respiratory Responses during Multiple-Pharyngeal Swallowing Sequences

Characteristic	Time-1 (n=80 stimuli)	Time-2 (n=80 stimuli)	P-value
Respiratory Response*
Deglutition apnea prevalence, %	99	97	0.4
Deglutition apnea duration, s	4.7 ± 0.5	3.2 ± 0.5	<0.01
Respiratory rhythm change, %	59	69	0.2
Respiratory rhythm change latency, sec	4.1 ± 0.3	4.0 ± 0.3	0.9
Respiratory response duration, sec	27.4 ± 3.0	22.1 ± 3.2	0.2
Composite Pharyngeal Response
Pharyngeal peaks, #	7.5 ± 0.4	5.1 ± 0.4	<0.01
Response duration, sec	16.8 ± 1.6	10.8 ± 1.6	<0.01
Frequency, Hz	0.7 ± 0.03	0.7 ± 0.03	0.9
Peak variability, sec	1.9 ± 0.2	1.4 ± 0.2	0.09
Peak stability	0.6 ± 0.05	0.4 ± 0.05	0.03
Initial Pharyngeal Response
Prevalence, %	96	84	0.08
Pharyngeal peaks, #	5.0 ± 0.4	3.0 ± 0.4	<0.01
Response duration, sec	6.1 ± 0.6	4.3 ± 0.6	<0.01
Frequency, Hz	1.1 ± 0.05	1.0 ± 0.05	0.2
Peak variability, sec	0.3 ± 0.04	0.3 ± 0.04	0.9
Peak stability, #	0.2 ± 0.02	0.2 ± 0.02	0.8
Subsequent Pharyngeal Response
Prevalence, %	64	61	0.9
Pharyngeal peaks, #	2.4 ± 0.4	2.2 ± 0.4	0.6
Response duration, sec	17.6 ± 2.4	12.1 ± 2.4	0.05
Frequency, Hz	0.2 ± 0.03	0.3 ± 0.03	0.06
Peak variability, sec	3.8 ± 0.5	2.3 ± 0.4	<0.01
Peak stability, #	0.8 ± 0.07	0.6 ± 0.07	<0.01

Data presented as mean ± SEM, All volumes were included however P-values were calculated controlling for volume. Note: Composite pharyngeal response is comprised of initial and subsequent pharyngeal responses. Results for deglutition apnea prevalence and duration apply to only to those responses where pharyngeal swallowing response was observed, whereas other respiratory characteristics apply to the total stimuli administered.