The significance of mother's perfume for infants in the first weeks of their life

Bottle-fed neonates prefer an odor experienced in utero to an odor experienced postnatally in the feeding context

“…This confirms earlier studies using the same (Schaal et al, 1995c;Marlier et al, in press;Schaal et al, in press) or different methods of odor presentation (Schleidt & Genzel, 1990;Sullivan, Taborki-Barka, Mendoza, Itano, Leon, Cotman, Payne, & Lott, 1991;Sullivan, Wilson, & Toubas, 1994). But the orientation response in the choice test was influenced by the side from which the stimulus was presented in interaction with the nature of the stimulus presented.…”

Olfactory alliesthesia in human neonates: Prandial state and stimulus familiarity modulate facial and autonomic responses to milk odors

“…In human infants, the feeding context also provides good conditions for formula milk odor to acquire reinforcing properties through associative learning. Such a process may work in human neonates for whom a novel artificial odorant can become a potent cue inducing preferential responding through either classical conditioning (Sullivan et al, 1991) or a recurrent association during breast feeding (Schleidt & Genzel, 1990). Future studies focusing on artificial odorants associated with suckling during feeding could provide insights to elucidate whether a biologically irrelevant stimulus can acquire postprandial aversive properties, as has been suggested for milk odor in these experiments.…”

Responsiveness to the Odour of Amniotic Fluid in the Human Neonate

“…In our test ing procedure, the infants evinced a response bias to the right for all the behavioural indexes recorded, including the one which was inde pendent of head orientation (oral activity). While the early latéralisation of cephalic mo tor activity has been described in previous studies of neonatal olfaction [24,[32][33][34], the side difference in spontaneous oral activity has not been reported so far. In the present experiment (as in [24]), the side effect and the odour attraction effect appeared to equili brate so that they cancelled each other out when opposed, but they produced optimal performance when confounded.…”

“…constant level. In contrast with the previous studies on early odour responsiveness (wherein neonates were tested while laying supine in their bassinet [21][22][23][24]), the babies were tested here in a semireclined position. They were installed in a seat especially devised for pre mature and term newborns with the back set at a 25° angle with the vertical.…”

“…The duration of head-turn ing to either stimulus was computed in two ways. First, a loose orientation criterion was used following pre vious studies on neonatal olfaction employing the dou ble-choice paradigm [23,24]; according to that criteri on, positive head-turning to a stimulus was defined as any deviation of the nose from the midline in that direction; to obtain this gross, right-left orientation measure, we aggregated the nose orientation durations of the four right and of the four left sectors; for each infant, the durations were summed across the two con secutive trials. Secondly, we defined a more stringent criterion of positive orientation response; with this cri terion, positive head-turning to a stimulus was decided when the nose was positioned within the sectors corre sponding to that stimulus pad; following this criterion, to be positively oriented, the nose had thus to deviate from the sagittal plane at a minimal angle of 20° to a maximal angle of 70° (i.e.…”