Respiratory rate in response to the odor of areolar secretion, sebum and milk.

<p>Mean (± sem) respiratory rate (RR) change of newborns during (2-sec stimulus blocks 1–5) and after (2-sec post-stimulus blocks 6–10) of the presentation of areolar secretions, sebum and human milk (key to abbreviations in legend of <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0007579#pone-0007579-g001" target="_blank">Figure 1</a>; n = 16).</p

Interactions between odor stimulus and test period for infant behavior.

<p>Matrix of p values of Fischer's LSD tests.</p><p>(Abbreviations: AG: secretion of areolar glands; S: sebum; HM: human milk; cow M: cow milk; FM: formula milk; van: vanillin; M: milk; f: familiar, nf: non familiar).</p

Inspiratory responses to areolar odor and to seven reference stimuli.

<p>Mean (± sem) of maximum change of inspiratory amplitude (IA_max) in newborns during (2-sec stimulus blocks 1–5) and after (2-sec post-stimulus blocks 6–10) binarinal presentation of the following stimuli: A) areolar secretion; B) blank (water); C) sebum; D) human milk; E) cow milk; F) formula milk; G) vanillin; and H) habitual milk (mother's milk in breast-fed and formula milk in bottle-fed infants). Key to abbreviations in legend of <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0007579#pone-0007579-g001" target="_blank">Figure 1</a>; values of IA_max in response to AG odor that differ significantly from the baseline are indicated by different letters; comparisons between the different stimuli (bold curves) and AG odor (red curves) are indicated by *, ** and ***: p<.05, .01 and .005, respectively; n = 16).</p

Areolar glands and infant behavior.

<p>A) Areola of a lactating woman (day 3 postpartum) with Montgomery's glands giving off their secretion (arrow). B and C) Newborns' oro-cephalic responses to the secretion of Montgomery's areolar gland (B: lip pursing; C: tongue protrusion). D) Mean (± sem) relative durations of newborns' oro-cephalic responses during (10-sec stimulus period) and after (10-sec post-stimulus period) presentation of various olfactory stimuli (Abbreviations: AG: secretions of areolar glands; S: sebum; HM: human milk; cow M: cow milk; FM: formula milk; van: vanillin; M: milk; f: familiar; nf: non-familiar; n = 19).</p

Cardiac response to the areolar odor and the reference stimuli.

<p>A) Mean (± sem) heart rate (HR) change of bottle- and breast-fed newborns in response to areolar secretions (n = 8 and 8; values of HR change of bottle-fed newborns in response to AG odor that differ significantly from the baseline are indicated by different letters); B to H) Mean (± sem) HR change of bottle-fed newborns during (blocks 1–5) and after (blocks 6–10) exposure to water (B), sebum (C), human milk (D), cow milk (E), formula milk (F), vanillin (G); and the infant's familiar milk (H) (Key to abbreviations, cf. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0007579#pone-0007579-g001" target="_blank">Figure 1</a>). Comparisons between the different stimuli (bold curves) and AG odor (red curves) are indicated by *, ** and ***: p<.05, .01 and .005, respectively; n = 8).</p

Intersubject neural synchronizations during interactional synchrony.

<p>Representation of statistically significant (P<0.05, nonparametric permutation test, corrected for multiple comparisons) coupling (PLV) for all subjects between electrodes of the model and the imitator: comparison for spontaneous imitation trials between behavioral synchrony episodes and those with no behavioral synchrony (Sync vs. NSync). On the left of the figures the participants are models, on the right the participants are imitators. A. Alpha-Mu band cluster between right centro-parietal regions. B. Beta band cluster between central and right parieto-occipital regions. C. Gamma band cluster between centroparietal and parieto-occipital regions.</p

Mean (and SD) percent time spent synchronizing and/or imitating hand movement during spontaneous imitation condition.

<p>Mean (and SD) percent time spent synchronizing and/or imitating hand movement during spontaneous imitation condition.</p

Experimental design and coding software.

<p>A. Apparatus and experimental setting of the double video system and dual-EEG recording. B. ELAN software window during an indexing session.</p

Experimental schedule.

<p>Experimental schedule.</p

Summary of relevant intersubject synchronizations for all dyads according to interactional synchrony.

<p>cPLV values indicate the averaged PLVs on all pairs of electrodes members of clusters shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0012166#pone-0012166-g002" target="_blank">Figure 2</a>. Averages cPLV across dyads are shown in black dashed lines.</p