*3.3. Correlation between Audiovisual Task and Communicative Skills*

Using the CSBS-DP we correlated concurrent communicative skills with infants' performance in the audiovisual task. For the current study we focused on skills that are relevant for infants' performance in audiovisual communication. Therefore, we analyzed data (raw scores) from the following scales: emotion and eye gaze, communication, and gesture. Nineteen TD infants (mean age 6 months, range 6–6 months), and six DS infants (mean age 6.8, age range 6–8 months) provided CSBS data. Note that for those infants that were younger than 6 months (i.e., the minimum assessment age for the CSBS questionnaire) at the moment of the AV task, the CSBS data were collected later (i.e., within the time span of 2–3 months for 2 of the infants). We observed that in the TD group there was a significant positive correlation between the proportion of looking to the eyes in the audiovisual task and the score on the gesture scale (r(18) = 0.47, *p* = 0.01), as well the communication score (r(18) = 0.36, *p* = 0.05). These results are depicted in Figure 4. In addition, we observed a marginal correlation between looking to the arm and the gesture score (r(18) = 0.34, *p* = 0.06). Other areas of interest did not provide a significant correlation with the CSBS scales (all *p*s > 0.1). Finally, for the DS group we observed no significant correlations (all *p*s > 0.2). *Brain Sci.* **2021**, *11*, x FOR PEER REVIEW 8 of 12 tion with the CSBS scales (all *p*s > 0.1). Finally, for the DS group we observed no significant correlations (all *p*s > 0.2).

**Figure 4.** Scatter plot representing the relation between attention to the eyes in the audiovisual task, and gesture and communication score from the CSBS-DP for the TD group. Dots represent individual scores. **Figure 4.** Scatter plot representing the relation between attention to the eyes in the audiovisual task, and gesture and communication score from the CSBS-DP for the TD group. Dots represent individual scores.

impaired in orienting their visual attention to salient stimuli.

velopment in DS and TD 5–7-months old infants. In particular, we assessed infants' early visual attention, audiovisual speech processing, and communication skills. We will discuss each of the assessed measures and their implications for language development, particularly for DS infants. First, we observed that DS infants are slower in orienting their visual attention to stimuli in comparison to TD peers. This means that DS infants need more time to start attending to salient visual cues in their environment, here a flashing red light. This result is in line with previous studies on impaired visual attention in DS toddlers and children, especially in disengaging their visual attention [34–36]. However, our results differ from Landry and Bryson's study [35] where DS preschool children were similar in the visual orientation task to TD children matched in mental age with the DS group. There are at least two explanations for these between-studies differences. First, we tested a much younger population than in Landry and Bryson [35] and it is possible that by the preschool age DS children do improve their visual orientation attention. Second, there are important methodological differences between studies. Note that we compared DS and TD infants that were matched in their chronological, rather than in their mental age. Considering that we were interests in assessing DS infants between 5–7 months of age it would be difficult, if not impossible, to match groups in their mental age. Moreover, our task required infants to turn and orient their head to lateral/central position to flashing lights, whereas Landry and Bryson [35] used a set up with a central monitor and two lateral monitors placed in front of the child. It is therefore possible that our task was particularly challenging for the Down syndrome group. Nevertheless, our study is one of the first studies demonstrating that in first half of the first year of life, DS infants are

The second component we assessed was infants' attentional pattern during audiovisual speech processing. We presented an animated character that waived and talked at the infant. We were particularly interested in examining what visual speech/communicative cues infants attend to at this age early age. We observed that the two groups demonstrated certain similarities in their looking pattern: both groups do attend less to the waving arm at this age than the face and the background, suggesting that at this age the waiving gesture is not a particular salient communicative cue. Further, when attending to the face, both groups look more at the eyes than the mouth, in line

**4. Discussion** 
