The studies we have completed so far

"Meaning of Pointing": How to interpret finger pointing

Pointing as a communicative gesture emerges early in development. Infants do not simply produce it to draw others' attention to something important; they can also understand when others point. However, pointing can indicate an important object that we want to show to others. At the same time, it can also provide information about the location or direction of a relevant place.

For instance, in a context where we point at an object and name it (“Look, it’s a ball”), pointing serves as a cue to highlight the object. In other cases, for example, when someone points toward an object inside a box, we can understand that they are not referring to the box itself but to the object inside it. Thus, pointing has two different meanings.

Historically, it was assumed that infants’ default interpretation of pointing is that it refers to an object rather than a direction. However, this question was never directly tested. Therefore, we designed a study to test whether infants, indeed, interpret pointing as referring to an object.

To test this prediction, 14-month-old infants were presented with two objects. Subsequently, one of the objects was pointed at and then swapped with the other (non-indicated) object. We hypothesized that if infants understand pointing as referring to an object, they should choose the one that was pointed at, irrespective of the fact that it is now in a new location. However, if infants interpret pointing as referring to a direction or location where an important or interesting object can be found, they should choose the non-indicated object now located in the indicated direction.

We found evidence showing that infants interpret pointing as indicating a direction rather than an object. These results align with our previous findings, which show that other species exhibit a similar tendency. This suggests that how humans interpret pointing may have an evolutionary ancient origin and that the canonical interpretation of pointing (as referring to objects rather than places) may follow an independent developmental trajectory. Importantly, since it is rare for an object to be replaced by another just after pointing, infants likely rely on pointing to learn about objects. However, it may take time for them to understand that pointing can serve different purposes.

Do you recognize the song? "Kinderlieder" study with 7 month old babies

Babies hear songs all over the world. The extent and the lyrics of the songs may differ, but all nursery rhymes have one thing in common: linguistic and melodic elements are combined. As part of our study, which is a cooperation between the Institute of Musicology and the Institute of Linguistics, we want to investigate which elements are particularly interesting for babies and whether they use these elements to recognize songs.

A total of 100 seven-month-old babies took part in our nursery rhyme study. At home, the families listened to a song composed especially for the study. In the Babelfisch laboratory, the babies where presented the same song again and also another, unknown song. Both songs were composed in such a way that the linguistic and melodic elements were of different lengths. Using the brain activity measured by EEG during the laboratory visit, we are studying whether these different lengths are also reflected in the brain activity. An initial, preliminary analysis has now shown us that the length of the bars, i.e. a melodic element, is more likely to be represented than the length of the notes, another melodic element. This result alone is very exciting, as it indicates that babies can already recognize bars without knowing what a bar is! We are very much looking forward to the results of further upcoming analyses and will report as soon as these have been completed.

Many Babies 3 study: Do 7-12 month old babies discover rules in syllable sequences?

Before babies even speak their first word, they have already learned a lot about their mother tongue(s): they can identify individual, recurring words and even recognize structural dependencies between words. As part of “Many Babies 3”, a large-scale study is investigating how exactly babies discover certain rules in simple syllable sequences. Over 40 development laboratories worldwide are taking part in this study. With such a large number of participants, it is hoped that the results will be particularly meaningful.

In the Babelfisch laboratory, we tested 40 babies aged between 7 and 12 months by measuring their eye movements. In a kind of “learning phase”, the babies first heard fantasy words that followed a certain rule: babies in group A heard fantasy words in the sequence ABB (e.g. lisoso, metata), babies in group B heard fantasy words in the sequence ABA (e.g. lisoli, metame). The children then heard new examples that either corresponded to the previously heard rule or deviated from it. Eye-tracking was used to measure which of these examples the babies paid attention to for longer. Did they look longer if they thought what they heard was familiar/new? This would be an indication that they had noticed and learned the previously presented rule. Or did they show no preference and looked for about the same length of time? A preliminary analysis of our data revealed no preference for either the familiar or the new rule. However, as our group only makes up a small proportion of the total number of babies tested worldwide, it may well be that such a preference only emerges across all participants.

We are looking forward to the results of the entire “Many Babies 3” project and will report again as soon as they are available! If you are interested, you can find more information on this and other large-scale developmental psychology studies at https://manybabies.org/.

"MOUTH" study: Do 7-9 month old babies imagine speech sounds?

Within the first few months of life, babies already gain a lot of experience with the audiovisual perception of speech whenever they not only hear people around them speak, but also watch them speak. In addition, babies begin to babble themselves from around the age of 7 months and thus gain their first experience with the production of speech sounds - and with how they sound and exactly what movements they produce. One unanswered question that concerns the Babelfisch team is whether babies can not only perceive and produce speech sounds in detail, but whether they can also imagine them in their “mind's ear”.

In our “MOUTH” study, we used eye-tracking to examine the babies' attention during the following task: first, they were presented with a silent video showing the face of a person uttering a speech sound (an “a”) or a non-speech sound (vibrating lips). Then only one sound was heard, without the video. The decisive factor was that the audible sound matched the previously shown video in half of the trials and not in the other half. Would the babies look for different lengths of time depending on whether the sound matched the video or not? If this were the case, it would be an indication that they had already imagined the linguistic or non-speech sound in their “mind's ear” when they only saw the mouth movement of the sound.

However, the results of our study with 7-9 month old babies could not prove such differences. Therefore, we cannot yet draw any conclusions as to whether babies imagine speech sounds. However, our results show that babies look attentively at the screen for longer when listening to speech sounds than when listening to non-speech sounds. Speech therefore always seems to be more interesting than other sounds, regardless of whether its occurrence was announced by visual information or not.

We will continue to work on this exciting question in the future to find out whether and, above all, from when babies can imagine speech sounds!