Interview with Joëlle Provasi: part 2

Joëlle Provasi, your research also focuses on rhythmic synchronisation in very young children interacting with their environment: how are young children able to perceive rhythms, produce them and modify them to synchronise with those of their environment?

Sensory-motor synchronisation (SMS) is the ability to modify one’s own rhythmic motor behaviour to synchronise with an external rhythmic behaviour. The most remarkable examples of sensorimotor synchronisation are musicians who are all capable of playing in rhythm, or dancers who synchronise their movements perfectly with those of other dancers. Without choosing such complex examples, sensorimotor synchronisation plays a crucial role in human communication, as it enables a person to show others that he or she perceives their behaviour and reacts accordingly.

The foetus is immersed in a rhythmic environment. Researchers have shown that in the last trimester of gestation, the foetus perceives its mother’s heartbeat and respiratory rate, the rhythm of language, singing and the rhythm of the mother’s walking. The foetus perceives these rhythms but reacts above all to changes in rhythm. The foetus is also capable of producing numerous rhythms: its own heartbeat, respiratory movements, with breathing becoming regular at 32 weeks gestational age, it also produces rhythmic movements of the jaw from 20 weeks gestational age, hiccups become frequent at 24 weeks gestational age and it also produces rhythmic movements of the legs as well as alternating movements of the legs. The crucial question for interaction is therefore whether infants, and even newborns, are capable of modifying their spontaneous rhythmic motor behaviour in response to external rhythmic stimulation This means, for example, being able to move at the same time as the music, or being able to modify their own rhythm to be in sync with their environment. To do this, you need to know when to produce your action so that it is at the same time as the other person’s action. It is therefore necessary to be able to anticipate the arrival of rhythmic stimulation, always with a slight time lag between the arrival of the rhythmic stimulation and the response. In newborns, non-nutritive sucking, crying (vocalisations that are the first signs of language) and leg movements were studied in the presence or absence of rhythmic auditory stimulation. The results suggest that the interaction between movement and sound is present from birth and that sensory-motor synchronisations can be observed under specific conditions and in a very narrow range of tempos, in particular close to the infant’s spontaneous motor tempo. We have been able to observe (Provasi, Anderson & Barbu-Roth, 2014) that under certain conditions newborns manage to synchronise the rhythm of their crying (vocalisations) to an audio-visual tempo. The researchers highlighted the fundamental role of sensory-motor synchronisation in interaction and communication at the beginning of life.

In the light of your research, how important is a rich multisensory environment in the first 1,000 days of life?

Sensory-motor synchronisation is a very good example of the importance of multisensory stimulation. Tempo, intensity and rhythm are stimuli perceived in several sensory modalities (Lickliter, 2018). For example, the rhythm and tempo of speech can be perceived by looking at the person speaking and listening to them. Rhythm and tempo are therefore characterised redundantly. Similarly, when the mother is walking, the sounds of her footsteps are often coordinated with tactile feedback, the foetus experiencing changing pressure corresponding to the temporal rhythm and changing intensity of the mother’s movements, as well as the accompanied and coordinated changes in the vestibular system. Multi-modal stimuli are better perceived by the foetus and the newborn than uni-modal stimuli. These multimodal stimuli have greater neurological effects than the sum of each stimulus (Lickliter & Bahrick, 2001). This inter-sensory redundancy can therefore be defined as the fact that the same information is available simultaneously and synchronised in time between two sensory modalities. This sensory redundancy is very important for promoting attention, learning and memory for properties of amodal stimuli such as tempo, rhythm and intensity (Lickliter, 2018). Imaging studies have also highlighted that motor areas are not only engaged during rhythm production tasks; they are also engaged during rhythm perception tasks (Janata & Grafton, 2003). Auditory and motor areas interact closely even during rhythm perception tasks. It is as if, in terms of brain activity, it is difficult to differentiate rhythm perception tasks from rhythm production tasks.

Lickliter (2018) has noted that social events provide particularly high amounts of sensory redundancy: speech sounds synchronised with coordinated movements of mouth, affect and gesture. Skin-to-skin contact is so important for newborn babies, and even more so for premature babies, because it resynchronises all the sensory signals that have been out of sync since birth (especially in the incubator). During skin-to-skin contact, the infant smells its mother, hears her heartbeat, feels the movements of her breathing, feels the vestibular movements when its mother walks, hears her voice if she speaks and can even see her face if she looks at him. All these stimulations occur at the same time; they are in sync and provide information that is redundant with each other. The mother (or parents) are fantastic multimodal stimuli!

This amount of sensory redundancy is much higher during social interaction than for most non-social events. When a person wants to communicate with a newborn or even a premature baby (see photo), they mobilise all their senses by wrapping their hands around the baby (tactile stimulation), turning the baby 45 degrees (vestibular stimulation), putting themselves very close to the baby’s face (around 25 centimetres, as a baby of that age cannot accommodate visually), talking to the baby (auditory stimulation) and being very close to the baby, the baby can even smell them. All the senses are called upon to set up a successful interaction and be in optimum conditions to be perceived by the infant. From the outset, babies discover the world in a multi-sensory way.

Many parent-child interactions, such as bouncing the child on the knee while singing a nursery rhyme, or the peek-a-boo game, are in fact combinations of multisensory stimuli. Learning is therefore multi-sensory. By simultaneously stimulating different sensory systems, multisensory experiences create neuronal connections that improve our ability to learn and remember. During this critical first 1000 days of life, a period of extraordinary growth and neurological plasticity, environmental influences can shape a child’s development.

It’s up to us, parents and early childhood professionals, to provide the developing child with a rich, dynamic multi-sensory environment that can evolve according to the child’s interests and abilities.

End of Part 2. To access part 1, please click here.