Methods
We Use Various Methods for Our Different Studies!
Exposure
In this procedure we place children in a room with toys and let them play while they hear a stream of speech or tones. We ask the parents not to speak to their children while in this room to allow the children to learn the words or tones that they hear. This procedure is always followed by one of the other testing methods below.
Listening Preference Task
In this method, infants are seated on their parent’s lab and look at a TV screen. We present the same simple object on the screen for each trial with different sounds. The sounds can be either non-sense words or tones. We then evaluate the amount of time the participant listens to the given label in each trial based on how long they look at the screen. Usually these studies test whether the child recognizes the sound they heard or pattern they learned from the previous exposure. We predict that they will listen to the unfamiliar labels or tones longer because infants have increased interest for new things and get bored with things that they have heard before. If they show a preference for either the new sounds or the old sounds, we can see that they recognize what they have previously been exposed to, which gives us an idea of how infants learn language.
Looking-While Listening Task
In this method, infants are seated on their parent’s lap and look at a TV screen. We present various objects projected on the screen accompanied with a tone or word label. The label and object pairing is repeated numerous times to teach the child to associate them together. In the testing trials we present two of the objects on the screen and play one of the labels from the previous pairings and see which object the participant looks at. It is predicted that the participant will look longer at the object that corresponds with the given label.
Eye Tracking System
This method uses similar procedures to both the looking-while-listening and listening preference tasks. The difference is that instead of manually recording the eye movements of the participants, their gaze and eye position is tracked by a computer.
Parent Report of Vocabulary Size
We use vocabulary forms to get information about the size of our participant’s vocabulary. We ask parents to identify words that their child understands and words that they can say. We have no expected amount of words that our participants should know. This information is used to see if vocabulary size correlates to the development of learning or performance of tasks in the different age groups.
Infant Development Scale
We will administer the Bayley Scales of Infant and Toddler Development (Bayley) to collect additional information about cognitive development. The cognitive section includes measures of skills such as attention, number knowledge, sorting, puzzles, and spatial memory.
Location Search Task
To collect additional information about cognitive development, we will administer an object location search task. In the task, a small toy is placed in one of two locations on the left and right sides of the infant. Both locations are then covered with cloths or other barriers and hidden out of reach. After a brief delay, the infant is encouraged to retrieve the toy. The trials are repeated on alternating sides.