Individual, Category, and No-label Conditions
Conditions
Brief summary
This work is guided by two specific aims and is expected to result in a better understanding of the effectiveness of shared book reading as a tool for supporting parent-infant interactions and infant learning across the first year of life. This work determined the extent to which books with individually-named characters (e.g., Boris, Fiona) increases parent-infant joint attention and infant selective attention relative to books with generic labels (e.g., Bear, Bear) or no labels and whether attention differs by age. During infant-parent shared book reading joint attention was measured using dual eye-tracking. Infants and parents then returned to the lab the next day and infant selective attention and infant-parent neural synchrony was measured using EEG.
Detailed description
Shared book reading has been found to have broad developmental benefits for language, socio-emotional and cognitive development. However, the effects of shared book reading on infant development are not well understood. Although healthcare professionals and educators ask parents to read books to their infants early and often, the book reading experience itself has never been systematically investigated in infancy. This work is guided by two specific aims and is expected to result in a better understanding of the effectiveness of shared book reading as a tool for supporting parent-infant interactions and infant learning across the first year of life. The primary aim of the proposed work is to determine the extent to which books with individually-named characters (e.g., Boris, Fiona) increases parent-infant joint attention and infant selective attention relative to books with generic labels (e.g., Bear, Bear) or no labels and whether attention differs by age. To address the aim of this project, a cross-sectional sample of 6-, 9-, and 12-month old infants and their parents came to the laboratory and read a book that includes three distinct character labeling conditions (individual names, generic category labels, no label). During infant-parent shared book reading joint attention was measured using dual eye-tracking. Infants and parents then returned to the lab the next day and infant selective attention and infant-parent neural synchrony was measured using EEG frequency tagging while infants and their parent viewed familiar characters across labeling conditions as well as unfamiliar characters. This project determined the extent to which parent-infant shared book reading impacted infant attention, parent-infant joint attention, EEG power, and parent-infant EEG synchrony.
Interventions
BEHAVIORALEffects of shared book reading: Labels
Book reading included objects labeled with 1) Individual labels, 2) Category labels, and 3) No Labels. Condition and infant age differences were examined.
Sponsors
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
University of Florida
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
NONE
Intervention model description
There were three age groups tested, but all infant-parent dyads were tested on the same conditions and measures.
Eligibility
Sex/Gender
ALL
Age
5 Months to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* Infants will be included if they are typically developing and between 5.5 and 12.5 months of age, as well as their caregiver. * Parents 18-65 years old
Exclusion criteria
1. Infants who were born more that 14 days premature. 2. Infants who with a history of neurological or visual deficits. 3. Infants with a history of seizures or a disorder that includes risk of seizures. 4. Infants with a parent that has a history of seizures of a disorder that includes risk of seizures. 5. Parents with a history of seizures or a disorder that includes risk of seizures.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Infant Visual Attention | Day 1 | Infant visual attention was measured for all 3 conditions using head mounted eye-tracking. Duration of visual attention (total duration of infant visual fixations greater than 100 ms each, to the book during shared book reading) was measured within a spatial window of the scene. Proportations of visual attention to the book were calculated by dividing attention duration to the book by the total task duration |
| Infant EEG Steady-state Evoked Potential Frequency Tagging Power | On Day 2 | To examine the extent to which infant EEG power, as measured by the signal-to-noise ratio (SNR) was modulated by label condition and age, data were extracted from a mid-occipital cluster of Oz and its 6 nearest neighbors (channels 70, 71, 74, 75, 76, 82, 83) for each of the conditions by age group. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Infant and Parent EEG Synchrony | On Day 2 | Infant and parent EEG synchrony (as a dyad) was quantified and compared across conditions. We used a phase-locking index to quantify EEG dyadic synchrony across conditions. The phase-locking index measures the extent to which the parent and infant oscillatory response is in the same phase across time. This index is bounded between 0 and 1, with 1 being perfect synchrony. |
| Parent-Infant Visual Joint Attention | On Day 1 | Parent and infant visual attention (as a dyad) was measured across conditions using dual parent and infant head mounted eye-tracking. Duration of joint attention (periods of overlap of parent and infant visual fixations to the book during shared book reading) was measured within a spatial window of the scene. Proportions of joint attention were calculated by dividing joint attention duration by the total task duration. |
Countries
United States
Participant flow
Recruitment details
Recruitment and study participation occurred between January 2022 and December 2023 in a research laboratory. Infant participants and their parents came in for two visits within one week, and were not followed up with beyond that.
Participants by arm
| Arm | Count |
|---|---|
| Infants Infants included three groups, 6-month-olds, 9-month-olds, and 12-month-olds. | 73 |
| Parents One parent of each infant was included in the dyadic data analysis. | 73 |
| Total | 146 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 | FG002 | FG003 |
|---|---|---|---|---|---|
| Day 1: Eye-tracking Measures | Equipment Failure | 0 | 0 | 2 | 2 |
| Day 1: Eye-tracking Measures | Protocol Violation | 1 | 3 | 7 | 11 |
| Day 2: EEG Measures | Lost to Follow-up | 0 | 3 | 2 | 5 |
| Day 2: EEG Measures | Protocol Violation | 6 | 6 | 5 | 17 |
Baseline characteristics
| Characteristic | Infants | Parents | Total |
|---|---|---|---|
| Age, Categorical Infants <=18 years | 73 Participants | 0 Participants | 73 Participants |
| Age, Categorical Infants >=65 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical Infants Between 18 and 65 years | 0 Participants | 73 Participants | 73 Participants |
| Ethnicity (NIH/OMB) Hispanic or Latino | 13 Participants | 10 Participants | 23 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 59 Participants | 63 Participants | 122 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 1 Participants | 0 Participants | 1 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 5 Participants | 5 Participants | 10 Participants |
| Race (NIH/OMB) Black or African American | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) More than one race | 8 Participants | 3 Participants | 11 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 1 Participants | 1 Participants | 2 Participants |
| Race (NIH/OMB) White | 59 Participants | 64 Participants | 123 Participants |
| Sex: Female, Male Female | 34 Participants | 14 Participants | 48 Participants |
| Sex: Female, Male Male | 39 Participants | 59 Participants | 98 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | 0 / 146 |
| other Total, other adverse events | 0 / 146 |
| serious Total, serious adverse events | 0 / 146 |
Outcome results
Primary
Infant EEG Steady-state Evoked Potential Frequency Tagging Power
To examine the extent to which infant EEG power, as measured by the signal-to-noise ratio (SNR) was modulated by label condition and age, data were extracted from a mid-occipital cluster of Oz and its 6 nearest neighbors (channels 70, 71, 74, 75, 76, 82, 83) for each of the conditions by age group.
Time frame: On Day 2
Population: Two dyads were excluded for technical issues during EEG recording, and 5 dyads who completed visit one but did not have EEG data collected.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Effects of Shared Book Reading: Effect of Labels 6 Month Olds | Infant EEG Steady-state Evoked Potential Frequency Tagging Power | Category | 7.298 Signal to Noise Ratio | Standard Deviation 0.606 |
| Effects of Shared Book Reading: Effect of Labels 6 Month Olds | Infant EEG Steady-state Evoked Potential Frequency Tagging Power | Individual | 7.270 Signal to Noise Ratio | Standard Deviation 0.856 |
| Effects of Shared Book Reading: Effect of Labels 6 Month Olds | Infant EEG Steady-state Evoked Potential Frequency Tagging Power | No Label | 7.256 Signal to Noise Ratio | Standard Deviation 0.879 |
| Effects of Shared Book Reading: Labels 9 Month Olds | Infant EEG Steady-state Evoked Potential Frequency Tagging Power | Category | 7.583 Signal to Noise Ratio | Standard Deviation 0.67 |
| Effects of Shared Book Reading: Labels 9 Month Olds | Infant EEG Steady-state Evoked Potential Frequency Tagging Power | Individual | 7.506 Signal to Noise Ratio | Standard Deviation 0.642 |
| Effects of Shared Book Reading: Labels 9 Month Olds | Infant EEG Steady-state Evoked Potential Frequency Tagging Power | No Label | 7.449 Signal to Noise Ratio | Standard Deviation 0.728 |
| Effects of Shared Book Reading: Labeling 12 Month Olds | Infant EEG Steady-state Evoked Potential Frequency Tagging Power | Individual | 7.392 Signal to Noise Ratio | Standard Deviation 0.639 |
| Effects of Shared Book Reading: Labeling 12 Month Olds | Infant EEG Steady-state Evoked Potential Frequency Tagging Power | No Label | 7.612 Signal to Noise Ratio | Standard Deviation 0.57 |
| Effects of Shared Book Reading: Labeling 12 Month Olds | Infant EEG Steady-state Evoked Potential Frequency Tagging Power | Category | 7.108 Signal to Noise Ratio | Standard Deviation 0.603 |
Comparison: EEG power, as measured by the signal-to-noise ratio (SNR) was modulated by label condition across age, data were extracted from a mid-occipital cluster of Oz and its 6 nearest neighbors (channels 70, 71, 74, 75, 76, 82, 83) for each of the conditions. SNR data were then submitted to a two-factor MANOVA with Label (Individual, Category, Control/No Label) as a within-subjects factor and Age (6 months, 9 months, 12 months) as a between-subjects factor. The main effect of age is reported here.p-value: =0.557MANOVA
Comparison: EEG power, as measured by the signal-to-noise ratio (SNR) was modulated by label condition across age, data were extracted from a mid-occipital cluster of Oz and its 6 nearest neighbors (channels 70, 71, 74, 75, 76, 82, 83) for each of the conditions. SNR data were then submitted to a two-factor MANOVA with Label (Individual, Category, Control/No Label) as a within-subjects factor and Age (6 months, 9 months, 12 months) as a between-subjects factor. The main effect of condition is reported here.p-value: =0.47MANOVA
Comparison: EEG power, as measured by signal-to-noise ratio (SNR) was modulated by label condition across age, data were extracted from a mid-occipital cluster of Oz and its 6 nearest neighbors (channels 70, 71, 74, 75, 76, 82, 83) for each condition. SNR data were then submitted to a two-factor MANOVA with Label (Individual, Category, Control/No Label) as a within-subjects factor and Age (6 months, 9 months, 12 months) as a between-subjects factor. The interaction of age and condition is reported here.p-value: =0.046MANOVA
Primary
Infant Visual Attention
Infant visual attention was measured for all 3 conditions using head mounted eye-tracking. Duration of visual attention (total duration of infant visual fixations greater than 100 ms each, to the book during shared book reading) was measured within a spatial window of the scene. Proportations of visual attention to the book were calculated by dividing attention duration to the book by the total task duration
Time frame: Day 1
Population: One infant was excluded due to equipment failure, 9 infants excluded due to unwillingness to wear the eye-tracking equipment, and 2 excluded for test dates falling outside the 28 day age group exclusion window.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Effects of Shared Book Reading: Effect of Labels 6 Month Olds | Infant Visual Attention | Category | .544 Proportion of Visual Attention Duration | Standard Deviation 0.236 |
| Effects of Shared Book Reading: Effect of Labels 6 Month Olds | Infant Visual Attention | Individual | .533 Proportion of Visual Attention Duration | Standard Deviation 0.206 |
| Effects of Shared Book Reading: Effect of Labels 6 Month Olds | Infant Visual Attention | No Label | .472 Proportion of Visual Attention Duration | Standard Deviation 0.222 |
| Effects of Shared Book Reading: Labels 9 Month Olds | Infant Visual Attention | Category | .300 Proportion of Visual Attention Duration | Standard Deviation 0.168 |
| Effects of Shared Book Reading: Labels 9 Month Olds | Infant Visual Attention | Individual | .358 Proportion of Visual Attention Duration | Standard Deviation 0.157 |
| Effects of Shared Book Reading: Labels 9 Month Olds | Infant Visual Attention | No Label | .257 Proportion of Visual Attention Duration | Standard Deviation 0.174 |
| Effects of Shared Book Reading: Labeling 12 Month Olds | Infant Visual Attention | Individual | .377 Proportion of Visual Attention Duration | Standard Deviation 0.252 |
| Effects of Shared Book Reading: Labeling 12 Month Olds | Infant Visual Attention | No Label | .404 Proportion of Visual Attention Duration | Standard Deviation 0.207 |
| Effects of Shared Book Reading: Labeling 12 Month Olds | Infant Visual Attention | Category | .351 Proportion of Visual Attention Duration | Standard Deviation 0.226 |
Comparison: To examine the impact of infant age and label condition on the proportion of infant's attention to the book, a 3 (infant age: 6, 9, or 12 months) x 3 (label condition: individual, categorical, or no label) MANOVA was run. Age was measured between subjects, label condition was within subjects, and infant's proportion of attention to the book was the dependent variable. The main effect of age is reported here.p-value: =0.002MANOVA
Comparison: To examine the impact of infant age and label condition on the proportion of infant's attention to the book, a 3 (infant age: 6, 9, or 12 months) x 3 (label condition: individual, categorical, or no label) MANOVA was run. Age was measured between subjects, label condition was within subjects, and infant's proportion of attention to the book was the dependent variable. The main effect of condition is reported here.p-value: =0.09MANOVA
Comparison: To examine the impact of infant age and label condition on the proportion of infant's attention to the book, a 3 (infant age: 6, 9, or 12 months) x 3 (label condition: individual, categorical, or no label) MANOVA was run. Age was measured between subjects, label condition was within subjects, and infant's proportion of attention to the book was the dependent variable. The interaction between age and condition is reported here.p-value: <0.05MANOVA
Secondary
Infant and Parent EEG Synchrony
Infant and parent EEG synchrony (as a dyad) was quantified and compared across conditions. We used a phase-locking index to quantify EEG dyadic synchrony across conditions. The phase-locking index measures the extent to which the parent and infant oscillatory response is in the same phase across time. This index is bounded between 0 and 1, with 1 being perfect synchrony.
Time frame: On Day 2
Population: The data represent the number of dyads (infant plus 1 parent) analyzed. Dyads were excluded for technical issues during EEG recording and 5 dyads were excluded because they completed visit 1 but did not have EEG data collected for Visit 2.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Effects of Shared Book Reading: Effect of Labels 6 Month Olds | Infant and Parent EEG Synchrony | Categorical Label | .471 Phase Locking Index | Standard Deviation 0.048 |
| Effects of Shared Book Reading: Effect of Labels 6 Month Olds | Infant and Parent EEG Synchrony | Individual Label | .478 Phase Locking Index | Standard Deviation 0.053 |
| Effects of Shared Book Reading: Effect of Labels 6 Month Olds | Infant and Parent EEG Synchrony | No Label | .471 Phase Locking Index | Standard Deviation 0.063 |
| Effects of Shared Book Reading: Labels 9 Month Olds | Infant and Parent EEG Synchrony | Categorical Label | .488 Phase Locking Index | Standard Deviation 0.043 |
| Effects of Shared Book Reading: Labels 9 Month Olds | Infant and Parent EEG Synchrony | Individual Label | .484 Phase Locking Index | Standard Deviation 0.048 |
| Effects of Shared Book Reading: Labels 9 Month Olds | Infant and Parent EEG Synchrony | No Label | .480 Phase Locking Index | Standard Deviation 0.043 |
| Effects of Shared Book Reading: Labeling 12 Month Olds | Infant and Parent EEG Synchrony | Individual Label | .461 Phase Locking Index | Standard Deviation 0.037 |
| Effects of Shared Book Reading: Labeling 12 Month Olds | Infant and Parent EEG Synchrony | No Label | .480 Phase Locking Index | Standard Deviation 0.034 |
| Effects of Shared Book Reading: Labeling 12 Month Olds | Infant and Parent EEG Synchrony | Categorical Label | .474 Phase Locking Index | Standard Deviation 0.034 |
Comparison: EEG Data were extracted from a mid-occipital cluster for each conditions for parents \& infants. Data were entered into a 2-factor MANOVA with Label (Individual, Category, No Label) as a within-subjects factor and Age (6 mo, 9 mo, 12 mo) as a between-subjects factor. The phase-locking index measures the extent to which the parent \& infant oscillatory response is in the same phase across time (bounded between 0 and 1, 1 being perfect synchrony. The main effect of age is reported here.p-value: =0.664MANOVA
Comparison: EEG Data were extracted from a mid-occipital cluster for each conditions for parents \& infants. Data were entered into a 2-factor MANOVA with Label (Individual, Category, No Label) as a within-subjects factor and Age (6 mo, 9 mo, 12 mo) as a between-subjects factor. The phase-locking index measures the extent to which the parent \& infant oscillatory response is in the same phase across time (bounded between 0 and 1, 1 being perfect synchrony. The main effect of condition is reported here.p-value: =0.768MANOVA
Comparison: EEG Data were extracted from a mid-occipital cluster for each conditions for parents \& infants. Data were entered into a 2-factor MANOVA with Label (Individual, Category, No Label) as a within-subjects factor and Age (6 mo, 9 mo, 12 mo) as a between-subjects factor. The phase-locking index measures the extent to which the parent \& infant oscillatory response is in the same phase across time (bounded between 0 and 1, 1 being perfect synchrony. The interaction of age and condition is reported.p-value: =0.2MANOVA
Secondary
Parent-Infant Visual Joint Attention
Parent and infant visual attention (as a dyad) was measured across conditions using dual parent and infant head mounted eye-tracking. Duration of joint attention (periods of overlap of parent and infant visual fixations to the book during shared book reading) was measured within a spatial window of the scene. Proportions of joint attention were calculated by dividing joint attention duration by the total task duration.
Time frame: On Day 1
Population: The data represent the number of dyads analyzed. 60 dyads (27 Female Infants, 33 Male Infants; 47 Female caregivers; 13 Male Caregivers) were included in the final sample. The final sample included dyads with 20 6-month infants, 23 9-month infants, and 17 12-month infants.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Effects of Shared Book Reading: Effect of Labels 6 Month Olds | Parent-Infant Visual Joint Attention | Category | .409 Joint Attention Proportion Mean | Standard Deviation 0.21 |
| Effects of Shared Book Reading: Effect of Labels 6 Month Olds | Parent-Infant Visual Joint Attention | Individual | .356 Joint Attention Proportion Mean | Standard Deviation 0.17 |
| Effects of Shared Book Reading: Effect of Labels 6 Month Olds | Parent-Infant Visual Joint Attention | No Label | .323 Joint Attention Proportion Mean | Standard Deviation 0.176 |
| Effects of Shared Book Reading: Labels 9 Month Olds | Parent-Infant Visual Joint Attention | Category | .222 Joint Attention Proportion Mean | Standard Deviation 0.15 |
| Effects of Shared Book Reading: Labels 9 Month Olds | Parent-Infant Visual Joint Attention | Individual | .262 Joint Attention Proportion Mean | Standard Deviation 0.145 |
| Effects of Shared Book Reading: Labels 9 Month Olds | Parent-Infant Visual Joint Attention | No Label | .180 Joint Attention Proportion Mean | Standard Deviation 0.167 |
| Effects of Shared Book Reading: Labeling 12 Month Olds | Parent-Infant Visual Joint Attention | Individual | .286 Joint Attention Proportion Mean | Standard Deviation 0.219 |
| Effects of Shared Book Reading: Labeling 12 Month Olds | Parent-Infant Visual Joint Attention | No Label | .254 Joint Attention Proportion Mean | Standard Deviation 0.179 |
| Effects of Shared Book Reading: Labeling 12 Month Olds | Parent-Infant Visual Joint Attention | Category | .276 Joint Attention Proportion Mean | Standard Deviation 0.198 |
Comparison: To examine the impact of infant age and label condition on the proportion of joint attention to the book, a 3 (infant age: 6, 9, or 12 months) x 3 (label condition: individual, categorical, or no label) MANOVA was run. Age was measured between subjects, label condition was within subjects, and the proportion of joint attention to the book was the dependent variable. The main effect of age is reported here.p-value: =0.022MANOVA
Comparison: To examine the impact of infant age and label condition on the proportion of joint attention to the book, a 3 (infant age: 6, 9, or 12 months) x 3 (label condition: individual, categorical, or no label) MANOVA was run. Age was measured between subjects, label condition was within subjects, and the proportion of joint attention to the book was the dependent variable. The main effect of condition is reported here.p-value: =0.004MANOVA
Comparison: To examine the impact of infant age and label condition on the proportion of joint attention to the book, a 3 (infant age: 6, 9, or 12 months) x 3 (label condition: individual, categorical, or no label) MANOVA was run. Age was measured between subjects, label condition was within subjects, and the proportion of joint attention to the book was the dependent variable. The interaction of age and condition is reported here.p-value: =0.168MANOVA