Clinical Trial Details
— Status: Active, not recruiting
Administrative data
| NCT number |
NCT04826978 |
| Other study ID # |
T352/2017 |
| Secondary ID |
|
| Status |
Active, not recruiting |
| Phase |
|
| First received |
|
| Last updated |
|
| Start date |
January 1, 2017 |
| Est. completion date |
March 30, 2023 |
Study information
| Verified date |
April 2021 |
| Source |
Turku University Hospital |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Observational [Patient Registry]
|
Clinical Trial Summary
Data on parent-infant physical closeness and infants' auditory environment will be collected
among preterm infants when they are at gestational age of 32 to 34 weeks. The follow-up
includes eye-tracker test at 7 months of corrected age for face preferences of the infants
and simultaneously parents' eye movements and pupil diameter responses. During the second
year, the follow up includes MacArthur Communicative Development Inventories (lexical
development) at 12 and 24 months of age; language development test (Reynell Developmental
Language Scales III) and developmental test (Bayley Scales for Infant development Edition
III) at 24 months of corrected age.
Description:
Study population: 63 infants from Turku University Hospital and 53 infants from Tallinn
Children's Hospital were recruited in 1/2017-12/2020. Inclusion criteria: Born before 32+0
week of gestation without life-threatening diseases or congenital anomalies or syndromes.
Infant auditory environment was recorded for 16 hours at 32+0 to 33+6 weeks of postmenstrual
age. In addition, Parental Closeness Diary was recorded for 14 days to measure the parents'
presence and parent-infant closeness to get an estimate of language environment of the child
during a 14-day period at around 32-34 weeks of gestation. Edinburgh Postnatal Depression
Scale was collected during the recording day from both parents to identify parents' risk for
perinatal depression. During the day of recording, the research nurse reported the time when
a nurse was in the patient room. The auditory environment will be analyzed quantitatively and
qualitatively.
Outcomes: Infant face preference for familiar and unfamiliar faces. At the corrected age of 7
months (± 7 days), an eye-tracking based test battery will be used to assess infants'
attention to familiar and unfamiliar faces. During the eye-tracking testing, the infants will
sit on their parents' lap at ~60 cm distance from a stimulus monitor. Infants' eye movements
will be measured by using a screen-based eye-tracker and a video camera.
The test will consist of a task assessing infants' attention to faces expressing neutral,
happy and fearful emotion, posed by the infant's own parents and an unfamiliar (female)
adult. In this task, the first stimulus (a non-face pattern or a face) is presented at the
participant's point of fixation in the center of the computer display, and the second
stimulus (a high-contrast distractor) 1 second later ~13-15° to the left or right of the
center. Gaze disengagement times from the central to the lateral stimulus will be extracted
from the eye tracking data (or from video data, if valid eye tracking data are missing).
Disengagement times from trials conforming to the following a priori inclusion criteria will
be used in the analyses: i) a sufficient length of fixation on the central stimulus (i.e.,70
% of the time) during the analysis period, which start at the onset of the trial and ends at
the onset of gaze disengagement or at maximum time out value (1000 ms post-target), ii)
sufficient number of valid samples in the gaze data (i.e., no gaps longer than 200 ms), and,
iii) valid information about the eye movement from the central to the lateral stimulus (i.e.,
the eye movement did not occur during a period of missing gaze data) will be retained for
analysis. The duration of attention dwell time on the first stimulus (face or non-face
pattern) will be determined for the period starting 150 ms from the onset of the lateral
stimulus and ending 1000 ms after the lateral stimulus onset. The duration will then be
converted to a normalized dwell time index score by using the formula described in Leppänen
et al. (2015). The shortest acceptable saccadic eye movement latency (150 ms) results in a
dwell time score of 0, and the longest possible latency (or a lack of saccade, which is equal
to the last measured time point of the first stimulus at 1000 ms) in a dwell time index score
of 1. The dwell time indices will be calculated separately for each trial and averaged for
non-face patterns (i.e., low-salience stimulus), for faces by familiarity (across emotion
categories), and for faces by emotion category (across familiarity and separately by
familiarity). The primary outcome of the analysis will be the mean dwell times for familiar
and unfamiliar faces, adjusted for the mean dwell time for respective non-face patterns. All
infants with >2 valid trials per condition will be retained in the final statistical
analyses.
Parents' attention and physiological responses to infant faces. Parents attentional and
physiological (i.e., pupil dilation) to non-face patterns and faces of their own infant(s)
and unknown infants will be assessed at infant age 7 months. Parents will be asked to provide
pictures of their own infant(s) prior to each laboratory visit. Pictures displaying
positive/content and distressed emotions will be asked.
Picture from an existing dataset will be used as unknown infant pictures. Non-faced patterns
will be created by phase-scrambling the pictures so that they retain the low-level
characteristics of the original faces, but are not identifiable as faces.
To assess attention, the adults will be asked to follow (by looking) a geometric shape (a
checkerboard pattern, measuring 2x2 degrees) as it shifts location from the center of the
screen (500-msec) to the left or right side of the screen (~13 degrees from the center).
After the participant has shifted gaze from the center to the side (as determined by the eye
tracker), the pattern will be replaced by a picture of a non-face pattern or a face for
300-msec. The side of the non-face pattern and face (A= non-face left, face right or B= face
left, non-face right) will be alternated between blocks of 20 trials following an ABBA-BAAB
design. Using this approach, estimates of saccadic reaction times (SRTs) to the location of
own infant face(s) vs. non-faces and two unknown infant faces vs non-face patterns. Because
saccadic reaction times will always be initiated by the shifting location of the shape (a
checkerboard pattern), any difference in mean SRT must reflect an endogenous or high-level
bias towards one of the stimuli (e.g. own infant face), instead of exogenous stimulus
properties. To extract attention indicators from the adult data, the latency of gaze shifts
between the center of the screen and lateral stimulus positions (following shifts in stimulus
position) will be analyzed by using the same procedures as those used for analyzing infant
attentional data. To assess parents' sympathetic activation to infant cues, we will follow
the procedures of our previous study (Yrttiaho et al., 2017). The adult will see a series of
trials consisting of a short 1000-ms pre-stimulus interval with the non-face pattern and a
4000-ms face stimulus (own or unknown infant). Pupil size will be measured from both eyes
during the pre-stimulus interval (with random visual pattern that has the same low-level
stimulus characteristics as paired face stimulus) and the presentation of the face stimuli.
By matching the low-level characteristics of the two consecutive stimuli, the present
approach minimizes the possibility that the recorded pupil dilation responses are driven by
changes in stimulus luminance. Latencies for each stimulus category will be extracted and
used as a primary dependent variable in subsequent statistical analyses. Physiological data
from adults (pupil diameter) will be preprocessed using the steps described in our previous
study (Yrttiaho et al., 2017), and pupil diameter in two time windows (based on prior
studies, these windows will be 300-1200 and 3000-4000 ms after face onset, respectively) will
be averaged to extract of pupil constriction and dilation, respectively. The dilation phase
will be used as the primary index of sympathetic arousal to infant distress cues.
Information about the child's developing abilities of early language (receptive and
expressive language development) will be assessed by MacArthur-Bates Communicative
Development Inventory (MCDI) at 12 and 24 months of corrected age.
At two years of corrected age the language skills of the children were measured using the
Reynell Development Language Scales III and MacArthur Communicative Development Inventories
(the Words and Sentences form). In addition, children's cognitive development was measured
using the Bayley Scales of Infant Development III.
