Maritza S. GomezUndergraduate Student Researcher (Class of 2014)

Brain & Cognitive Sciences

Majors: Psychology, Linguistics

University of Rochester

The role of parental labeling in early language development

2013 Sigma Xi Undergraduate Research Showcase

March 18-23, 2013

Introduction

Background

Significance

Research questions

External linguistic input required

＊ Infants require external linguistic input to

acquire their first languages

＊ Experienced language users provide infants

with particular sounds, words, and

grammatical rules for their target language

＊ Example: Word an infant will learn for “milk”

depends upon the language environment

(e.g., leche in Spanish,laitin French)

Parents as primary input providers

＊ Parental labeling behavior plays a very important role in children’s early language learning

＊ More parental language input thought to yield faster word learning(e.g., Hurtado et al. 2008, Fernald et al. 2006)

Previous studies of word learning

＊ Previous work focused on how infants solve

mapping problem using distributional

statistics

＊ Infants employ cross-situational statistics to

rapidly learn word-object pairings(e.g., Smith & Yu, 2008; Yu & Smith, 2011)

＊ Input is typically thought of as a running

stream of word- and object co-occurances

that unfolds over time—independently of

what the infant thinks or does

Proposed alternative possibility

＊ Parents could adjust what they say to

their infants as a function of their

infants’ changing knowledge states

＊ Could potentially give infants a boost

in process of learning first language

＊ Parents could be providing learning

material that is “just right” for efficient

learning

Research questions

＊ Is parental language

input dynamically

related to the infant’s

knowledge state?

＊ Are parents more

likely to label objects

for which their infants

already have some

existing knowledge?

Methods

Data collection

Analyses

Data collection

＊ Worked with

research team to

collect video data of

infants and parents

engaged in

naturalistic play

＊ Head-mounted

camera sets on

infant and parent

captured video

Volunteer subjects

＊ Parents with infants recruited

from the Rochester, NY area

＊ Ages 12- to 15-

months-old (M =

13.4, N =12)

Data collection

＊ In each 3-minute trial, parent and infant

provided with 4 to 8 toys

＊ Each toy set contained a mixture of both

familiar objects (e.g., ball) and unfamiliar

objects (e.g., lobster)

Labels and vocab surveys

＊ In each trial, parents naturally provided

labels for toys in the scene

＊ Each label was recorded

＊ Vocabulary surveys also collected from

parents after play sessions

＊ Surveys asked which words infants understood

＊ Two analyses conducted to test whether parents were more likely to use labels their infants understood

Study 1: Difference of

means

Difference-of-means test methods

t-test results

Study 1: Analysis

＊ Computed the mean number of labels a

parents for two different object

categories:

Known—objects for which infant knew the label

Unknown—objects for which infant did not know the label

＊ Significance of difference tested with

Welch’s t-test (independent samples)

Study 1: Results

Known Unknown

Child's Knowledge of Labels

Nu

mb

er

of

La

bels

Pro

du

ce

d b

y P

are

nt

02

46

81

0

* p< .05

Study 1: Results and conclusions

＊ Plot shows parents use significantly more labels for objects that are known (familiar) to their infants than for those that are unknown (unfamiliar)

＊ But is this difference due to some factor other than infants’ knowledge (e.g., maybe the fact that older infants knew more labels drove the effect)?

＊ Second analysis controls for a number of relevant factors

Study 2: Generalized

linear mixed model

GLMM analysis methods

GLMM results

Study 2: Analysis

General linear mixed model to test whether child’s knowledge of the label predicts number of parental labels, controlling for:

＊ Age

＊ Total number of objects present in trial

＊ Total number of labels parent produced in

trial

＊ Factor for random subject effects

Study 2: Results

Study 2: Results and conclusions

＊ Infants’ knowledge of the label was a significant predictor of the number of times a parent used that label

＊ Effect was significant, even controlling for other factors (e.g., infants’ age, number of objects present)

＊ Number of labeling events (control variable) was also significant; parents who produced lots of labels were more likely to produce a particular object label

Summary and future

directions

Summary

Discussion

Future directions

Summary and discussion

＊ Results evidence a dynamic relationship between parental labeling behavior and infant’s vocabulary knowledge

＊ Could either be the case that parents are more likely to use labels that infants understand, or it could be the case that infants are quicker to learn labels that parents use more often

＊ Future work in progress will disentangle two possible explanations for correlation reported here

Future directions

＊ Follow-up research will collect measures of parental productions and children’s vocabulary in the home

＊ This work will allow us to collect greater quantity of data at multiple time points

＊ Aim is to determine to what degree parents’ labeling behavior drives children’s lexical development

Potential impact of research

＊ Research aims to better understand what type of learning environments are most conducive to language learning

＊ Work will yield normative baselines for language development

＊ Baselines can be used to develop more effective language therapies for children with delayed language development

Acknowledgements

Thank you to:

＊ My research project advisors, Dr. Richard N. Aslin and Celeste Kidd

＊ Rochester Baby Lab research staff, especially lab manager Holly Palmeri and postdocs Dr. Steven T. Piantadosi and Dr. Lauren Emberson

＊ LocalLocal.tvfor video of infants in lab

＊ Volunteer parents and infants for participating in this research

Thank you.