Heather Bortfeld

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How do infants find the words in the tangle of speech that confronts them? The present study shows that by as early as 6 months of age, infants can already exploit highly familiar words-including, but not limited to, their own names-to segment and recognize adjoining, previously unfamiliar words from fluent speech. The head-turn preference procedure was(More)
Measurements of human brain function in children are of increasing interest in cognitive neuroscience. Many techniques for brain mapping used in children, including functional near-infrared spectroscopy (fNIRS), electroencephalography (EEG), magnetoencephalography (MEG) and transcranial magnetic stimulation (TMS), use probes placed on or near the scalp. The(More)
Sensitivity to spoken language is an integral part of infants' formative development, yet relatively little is known about the neural mechanisms that underlie the emerging ability to perceive and process speech. This is in large part because there are a limited number of non-invasive techniques available to measure brain functioning in human infants.(More)
We investigate the utility of near-infrared spectroscopy (NIRS) as an alternative technique for studying infant speech processing. NIRS is an optical imaging technology that uses relative changes in total hemoglobin concentration and oxygenation as an indicator of neural activation. Procedurally, NIRS has the advantage over more common methods (e.g., fMRI)(More)
In a series of studies, we examined how mothers naturally stress words across multiple mentions in speech to their infants and how this marking influences infants' recognition of words in fluent speech. We first collected samples of mothers' infant-directed speech using a technique that induced multiple repetitions of target words. Acoustic analyses(More)
The capacity to represent the world in terms of numerically distinct objects (i.e., object individuation) is a milestone in early cognitive development and forms the foundation for more complex thought and behavior. Over the past 10 to 15 yr, infant researchers have expended a great deal of effort to identify the origins and development of this capacity. In(More)
Cochlear implants (CI) are commonly used to treat deafness in young children. While many factors influence the ability of a deaf child who is hearing through a CI to develop speech and language skills, an important factor is that the CI has to stimulate the auditory cortex. Obtaining behavioral measurements from young children with CIs can often be(More)
Over the last 20 years neuroscientists have learned a great deal about the ventral and dorsal object processing pathways in the adult brain, yet little is known about the functional development of these pathways. The present research assessed the extent to which different patterns of neural activation, as measured by changes in blood volume and oxygenation,(More)
Learners of a second language practice their pronunciation by listening to and imitating utterances from native speakers. Recent research has shown that choosing a well-matched native speaker to imitate can have a positive impact on pronunciation training. Here we propose a voice-transformation technique that can be used to generate the (arguably) ideal(More)
Functional neuroimaging can provide insight into the neurobiological factors that contribute to the variations in individual hearing outcomes following cochlear implantation. To date, measuring neural activity within the auditory cortex of cochlear implant (CI) recipients has been challenging, primarily because the use of traditional neuroimaging techniques(More)