Time series changes of the salivary secretory immunoglobulin A (s-IgA) response to acute laboratory stress tasks were investigated. Participants (N=29) performed three tasks at weekly intervals; mental arithmetic (active stress coping), cold pressor (passive stress coping), and watching a neutral video (control). Five saliva samples were obtained during the baseline,the task, and the recovery period in each condition. Results indicated that during the first half of the mental arithmetic task s-IgA secretion rate decreased significantly and increased significantly immediately after the task in comparison to the control condition. Conversely, in cold pressor condition, the s-IgA secretion rate decreased significantly immediately after the task, in comparison to the control condition. These results suggest that the timing of saliva sampling influences the observed s-IgA values during active and passive coping stress tasks.

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Temporal respiratory change responses were investigated in 113 concealed information tests (CITs) conducted in the field. The guilty knowledge of all CIT examinees was confirmed in subsequent investigations. Respiratory amplitude (RA), respiratory rate (RR), and respiratory speed per cycle (RS^cyc) were measured each second for 25 seconds following stimulus onset. The results indicated that RA, RR, and RS^cyc decreased significantly for the critical item, in comparison to the non-critical item in the period between 1 and 18 s, 9 and 25 s, and 2 and 25 s after stimulus onset. Result of the detection rate indicated even more remarkable differences in temporal characteristics between RA and RR. Moreover, detection rate in RS^cyc was superior to those of RA and RR.

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Stiffening of the small artery may be the earliest sign of arteriosclerosis. The photoplethysmographic-derived index of finger arterial stiffness (FSI) had been developed as a blood pressure independent measure, based on an exponential model of pressure-arterial volume relationship in the finger artery. In this study, a novel measure of FSI for high transmural pressure range (FSIH) is evolved which is more relevant to the arteriole component and examined in diabetes patients. Participants were 31 ophthalmic middle-aged patients who were assigned to three groups: diabetes (DM, 7 patients), diabetes complicate hypertension (DH, 12), and controls (CT, 12). FSI and FSIH had been previously standardized as 50 ± 10 for a healthy young population. FSI in DH (73.8 ± 11.3) was significantly higher than CT (54.7 ± 11.8), while intermediate in DM (65.0 ± 14.6). FSIH was significantly higher in DM (91.2 ± 22.9) and DH (83.8 ± 31.1) patients than CT (61.0 ± 12.1). These findings suggest that FSI and FSIH are associated with the stiffness of the small artery and arteriole in the finger, respectively.

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To investigate the relationship between the long-term language-specific speech sound memory traces revealed by mismatch negativity (MMN) and language representations used in phonological loop, we evaluated the effects of subvocal rehearsal and irrelevant speech on MMN. In Experiment 1, MMN to sinusoidal tones or Japanese vowels were recorded from eight adult participants while they repeatedly rehearsed a nonword subvocally, or only watched the videos. Nonword rehearsal, thus load to an articulatory control process, did not affect any MMN. In Experiment 2, two kinds of background noise (piano sound and male voice) were presented to twelve participants when recording MMN. Irrelevant speech, namely, the disturbance to a phonological store, decreased the amplitude of MMN to vowels compared with the MMN recorded with no background noise, but had no effect on MMN to pure tones. These results suggest that the neural basis for MMN to speech sound is also involved in a phonological store which closely relates to the speech perception process.

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